Project Data

End-User: 

Installer: 

Location: 

Date of install: 

Size of system in kW: 

Energy produced since installation

Special Challenges Met: 

Project Brief:

Architecture Firm: Gwathmey Siegel Architects

Client: New Jersey Institute of Technology

Date of Construction Completion: Sept. 2005

John Millard's Role: Client Contact, Contractor Contact, Engineering Contact, Overall System Designer, Construction Administrator, Installation Trainer, Logistics of PV System Supply, Construction Finance Provider and Commissioning/ Monitoring Supervisor.

Date of Design Effort Complete: Schematic Design- November 2004, Design Development- May 2005, Construction Documentation- Jul 2005

John Millard started a company in 2003 that was a well financed solar energy integration company called TurtleEnergy, a subsidiary of Turtle & Hughes, Inc, a $300M electrical sales and marketing company that had been a family owned company for 80 years. The TurtleEnergy concept was a belly laugh to most seasoned electrical executives in 2003- the idea that solar energy might somehow find its way into the mainstream of electrical sales was considered a long shot. Despite their viewpoint, the New Jersey Solar Market would grow to a 1GW,  $1B industry in less than ten years and TurtleEnergy would have a 10% market share of commercial solar electric system integration within three years of inception. By 2006, TurtleEnergy would have over 2MW of smaller commercial, grid interactive systems operational and performing as predicted. The NJIT project, a 50kW roof mounted system at the brand new NJIT Campus Center designed by Gwathmey Siegel Architects would set the pace of growth for this small solar startup. 

The Architect, Gwathmey Siegel was one of the first design architects to embrace the green building revolution. The parallel ridicule that was being visited upon the architects by the construction industry as that which was being experienced by participants in the Electrical Industry. The Campus Center's "greenness" was expressed in the design by installing planters on the roof that would enable trees and ground-cover to be grown on the roof around a centerpiece of green electric generation for the building's electrical consumption- a roof mounted solar photovoltaic PV system. This idea was promoted by the campus intellectuals who pointed to the recent attacks on 9/11/2001 as evidence that the USA was in need of "energy independence" and that a trickle of that vaccine might come in the form of a small PV project to set an example for the students that their college was a forward thinker. Gwathmey Siegel embraced the project brief with an elegant response to the project by recycling the existing campus center concrete frame and enshrouding it with a circular apron enclosure that resulted in sweeping curving curtain-wall glass surfaces inside the circular residual spaces outside of the square concrete frame at the core of the design. The roof structure of this legacy concrete structure would not, as it would turn out, sustain the weight of planters deep enough to support the growth of trees on the roof- a major feature of the green roof. The solar PV System however, with its extremely high cost and sensitvity to shadows from trees functioned much more efficiently without the tree-shade crippling the production of electricity from the sun.

The rock-star solar company that was originally consulted to provide a PV System for the project was The Powerlight Corporation from California where the state had an array of incentives to promote the growth of solar at a cost of $9/Watt (a typical PV System today costs $2 - $3/W and is twice as efficient). The Powerlight Corporation was purchasing Sanyo HIT modules and mounting them on specially formed rigid insulation, large, roof tiles that interlocked together so that the solar panels that were adhered to the rigid insulation like rafts produced electricity while the rafts added thermal performance to the roof structure, theoretically reducing the heating bill in the winter and the cooling bill in the summer. NJIT was sold on this product and based the design of the buildings roof mounted PV system on Powerlight's "PowerGuard" System. Today, this product is no longer manufactured, despite the conceptual genius of it. In practice, the rigid insulation rafts that supported the solar panels became mould and algae farms on the roof that re-entrained spores into the roof mounted supply air ducts and infected the entire ventilation system of the building with "sick building syndrome". In some cases, the weep holes in the rafts became clogged and no longer drained rainwater adequately, increasing the weight of the system on the roof beyond safe tolerances and had to be removed. At the time of the project on the NJIT Campus Center, there were legal conflicts between Cornell University and the aforesaid solar rock star company over the "Powerguard" system that had been installed on Cornell University Building in Ithaca, NY.

TurtleEnergy learned of the NJIT project from the electrical contracting community who had contacted the parent company, Turtle & Hughes for pricing on some panel-boards for the solar electric system specified for the project. What began as a pricing inquiry for a $400 order turned into a $213k order for a Schott Solar FS System- a US made solar panel and mounting system that made a great deal more sense to NJIT decision-makers other stakeholders in the project. With a few short months the TE team had conveyed enough factual information about the Schott System to the NJIT project that resulted in the adoption of the Schott System as a superior solar electric system. The selling points: No mould or algae buildup, Cooler operation for the PV module, plenty of roof drainage as well as ventilation under the module. Nevertheless, the design was suffering from the fact that the specification called for 50kW and the Sanyo HIT Module that Powerlight was selling was more efficient than the Schott Solar Module. This turned out to be another bullet that the NJIT project dodged- The Sanyo HIT Module would later in 2005 be recalled due to "arc" flashing of electricity to the aluminum frame of the module. This phenomenon is mitigated by designing a larger space around the solar cells in the perimeter of the solar panel (where the aluminum frame encapsulates the eddges of the cells). Schott had a generous gap to prevent electricity from escaping from the cells onto the frame- but this additional space reduced the "efficiency" of the module which was the Watts per Square Foot of Module factor that manufacturers "pushed the envelope" of by minimizing that space. Sanyo was, at the time the most efficient solar module in the industry and consequently, bragging rights for anyone who was priviledged and fortunate enough to have a supply agreement with Sanyo. Companies that were cozy with Sanyo were the envy of the industry. At solar conferences, heads held high wearing Sanyo Tee shirts to vaunt the relationship were later an industry joke when ground faults were reported at Sanyo projects worldwide. To this day, Sanyo Modules are still some of the most efficient, but the company is now owned by Panasonic after Sanyo hemorrhaged hundreds of millions dollars (among other solar losses) due to the recall.

The NJIT design had to be improved since there was not the area on the NJIT roof to fit 50kW of Schott Solar Modules. Therefore the design evolved into a 44.9kW roof mounted design with 5kW (qty(16) 315W Modules) mounted on 2 axis trackers by Array Technologies of Albuquerque, New Mexico. These trackers would be incorporated into the structural frame of the building and become a distinctly prominent feature of the roofscape. They would also prove to enable wintertime power production that would better the 5 degree roof mounted modules by 10X. This added cost to the project that the NJIT team were happy to pay for because they wanted us to create a more overt feature that would make the solar component of the building more visible to the public. The very idea of mounting four 100 square feet of glass-encapsulated semiconductor material on 8" pipe at the top of a four stories of University Center was a risk profile that departed dramatically from TurtleEnergy's parent company's core business which was placing electrical merchandice safely in a box and placing a postage stamp and a "ship to" address on the outside of the box and sending the box to a customer by Fedex, UPS, or Best Way- for a 30% profit. Saving the earth from carbon dioxide emissions and reducing global warming were not considered high on the list of corporate mission statements. In fact, the 50kW PV System produced less than 10% of the Campus Center's electricity.

Once the contract with NJIT was secured by our customer, LB Electric, an electrical contractor, and a Minority Business Enterprise, the waiting game had begun for the demolition, construction and enclosure of the new building to be completed by the Construction Team. The Construction Manager, Turner Construction was very much engaged in understanding the structural, electrical, mechanical and civil engineering requirements of the Solar Energy System that TurtleEnergy was providing to LB Electric, and hence, to NJIT. The Turner team adopted the changes necessary to accommodate the 2 Axis Trackers by engaging the project Structural Engineer, Harrison Hamlet to design the attachments necessary to keep the trackers from blowing off the roof onto the student population below. To the surprise of all, the structural engineer solved this component with a few calculations on a pad of paper. He wrote the attachment specification into a change order and the solution was very elegant.

Project Data

End-User: 

Installer: 

Location: 

Date of install: 

Size of system in kW: 

Energy produced since installation

Special Challenges Met: 

Project Brief

Architecture Firm: Gwathmey Siegel Architects

Client: New Jersey Institute of Technology

Date of Construction Completion: Sept. 2005

John Millard's Role: Client Contact, Contractor Contact, Engineering Contact, Overall System Designer, Construction Administrator, Installation Trainer, Logistics of PV System Supply, Construction Finance Provider and Commissioning/ Monitoring Supervisor.

Date of Design Effort Complete: Schematic Design- November 2004, Design Development- May 2005, Construction Documentation- Jul 2005

Introduction to Photovoltaics

􀂄 Photovoltaic systems are given strict guidelines by the National Electrical Code like any other type of electricity g enerating system.

􀂄 Photovoltaic system voltage may range from hand held calculator voltage to over 1200 Volts Direct Current with DC current ranging from 1amp to over 800amps.

􀂄 PV power output ranges from a few watts to several megawatts. 􀂄 PV systems can cause personal harm and property damage and must be installed with great duty of care.

Differences between PV systems and conventional electricity from the National Grid:

􀂄 PV systems have DC circuits which require special design & equipment. 􀂄 PV systems have dispersed energy sources which require special disconnects inorder to isolate them.

􀂄 Energy flow in a PV System may be bi-directional.

Common Installation Problems

􀂄 Insecure structral attachment of PV Arrays to Rooftops

􀂄 Inadequate weather sealing for rooftop penetrations.

􀂄 Unsafe wiring methods insufficient conductor ampacity and insulation type.

􀂄 Lack of or improper placement or ratings of overcurrent protection and disconnect devices. Unsafe installation, improper use and maintenance of batteries.

􀂄 Use of unlisted equipment or improper application of listed equipment.

􀂄 Lack of or improper system grounding.

􀂄 Lack of or inadequate labling on major system components and disconnect devices.

􀂄 Lack of or inadequate documentation on system design and operating and maintenance requirements.

A Brief History of Photovoltaics:

1839 Edmund Becquerel, the French experimental physicist, discovered the photovoltaic effect while experimenting with an electrolytic cell.

1904 Albert Einstein, in his first published scientific paper, explains the photovoltaic effect by describing light in terms of “Quanta” he called “photons”. This laid part of the foundation for Quantum Theory.

1921 Albert Einstein wins the Nobel Prize for his theory explaining photovoltaics. 1958 Vanguard I, the first PV-powered satellite, is launched.

1973 The Terrestrial solar industry is born at a conference in Cherry Hill, New Jersey.

2002 Worldwide production capacity for Photovoltaics surpasses 350 Megawatts per year, growing at a 20% per year pace. Grid connected PV grows at a rate of 100% per year.

2012 Worldwide production capacity for Photovoltaics surpasses 100 Gigawatts per year, an increase by 285X in one decade. By the end of 2013, worldwide installed photovoltaic capacity reached 139 gigawatts, close to 1 percent of the total electricity generation on the planet.[6] For 2014, another estimated 35 to 52 GW will be installed, and by 2018 the worldwide photovoltaic capacity is projected to have doubled (low scenario of 320 GW) or even tripled (high scenario of 430 GW) within five years.[1]

Current status

  Europe: 81,488 MW (58.7%)

  APAC: 21,992 MW (15.8%)

  China: 18,600 MW (13.4%)

  Americas: 13,727 MW (9.9%)

  MEA: 953 MW (0.7%)

  RoW: 2,098 MW (1.5%)

Worldwide

In 2013, another 38,400 MW of PV installations have been deployed. This is a new all time record in the history of worldwide PV growth and about 8,400 MW more than was deployed in the year before. The cumulated photovoltaic capacity increased by 38 percent to a running total of 139 GW. This is sufficient to generate at least 160 terawatt hours (TWh) of electricity every year[1] and about 0.85 percent of the electricity demand on the planet.[6]

Regions

Europe added 11 gigawatt of new PV installation in 2013. It is still the most developed region with a cumulated total of 81.5 GW, about 59 percent of the worldwide installed capacity. Solar PV now covers 3 percent of the electricity demand and 6 percent of the peak electricity demand. However, European PV deployment has slowed down by half compared to the record year of 2011, and will most likely continue to decrease. This is mainly due to the strong decline of new installations in Germany and Italy.

Countries

In 2013, photovoltaics grew fastest in China (+11.8 GW), followed by Japan (+6.9 GW) and the United States (+4.75 GW), while Germany remains the world's largest overall producer of photovoltaic power with a total capacity of 35.5 GW, contributing almost 6% to its national electricity demands. By now, Italy meets 7.8% of its electricity demands with photovoltaic power, thus making it the leader in that respect.

For the top ten leading countries in terms of deployed and overall PV-capacity see chart below. Other mentionable PV deployments in 2013, include France (613 MW), Canada (444 MW), Korea (442 MW), Thailand (317 MW), The Netherlands (305 MW), Switzerland (300 MW), Ukraine (290 MW),Austria (250 MW), Denmark (216 MW), Belgium (215 MW) and Spain (115 MW).

Elements of a Code Compliant PV System:

􀂄 Sysem employs a well engineered design and quality components.

􀂄 System and equipment are properly sized to meet expected or required performance.

􀂄 Sysem uses listed, aproved and apropriately rated equipment with ultraviollet light resistant materials for outdoor application.

􀂄 PV Array is mounted in an unshaded, accessible location with proper solar orientation, and if it uses roof penetrations, they shall be sealed with methods consistent with roofing industry practices.

􀂄 All equipment is properly labeled and safety hazards identified.

􀂄 Installation complies with all applicable building and electrical codes and accepted utility interconnection practice.

􀂄 System is inspected and approved by utility and code officials, owners/operators are trained on safety and operation.

Characteristics of a Installer:

􀂄 Possesses knowledge, skills and experience in working with electrical systems and PV Equipment.

􀂄 Properly selects, sizes systems and equipment to meet performance expectations.

􀂄 Applies for permits and utility interconnection approval.

􀂄 Practices safe, clean and orderly work habits.

􀂄 Employs accepted methods for the use and installation of PV Equipment and completes work in a timely, efficient manner. Completes inspections, commissioning, acceptance tests and transfer to owner/ operator.

􀂄 Provides follow-up service as required.

Documents provided to each Installation:

􀂄 Complete system and equipment specifications/ owner’s manual Electrical Schematics and mechanical drawings

􀂄 Parts, materials and source lists.

􀂄 Installation and checkout procedures.

􀂄 Operation, troubleshooting and maintenance proceedures.

Inverters and Utility Interconnection for PV Systems

􀂄 Inverter (690.2)-

􀂄 Equipment that is used to change voltage level or waveform , or both, of electrical energy. Also known as a power processing unit (PCU), or power conversion system (PCS), and inverter is a device that changes dc input to ac output. Inverters may also function as battery chargers that use alternating current from another course and convert it into direct current for charging batteries.

􀂄 Inverters for PV Systems are available in sizes from 100 watts to 1MW or more.

􀂄 DC Operating voltages from 12 volts to 600 volts with AC outputs from 120V single phase to 480 volts 3Phase.

􀂄 DC Operating voltages from 12 volts to 600 volts with AC outputs from 120V single phase to 480 volts 3Phase.

Different configurations for PhotoVoltaic Systems:

Stand alone Inverters- Inverter in any photovoltaic system which converts the wave form of electrical current and is independent of any electrical production and distribution network. Typically, stand alone inverters charge a battery bank.

Inverter Output Circuit Current:

The maximum current shall be the maximum output current rating. {(690.8) (A)(3)}

Stand-Alone Inverter Input Circuit Current: The maximumcurrent shall be the standalone continuous inverter input current rating when the inverter is producing rated power at the lowest input voltage. {(690.8) (A) (4)}

IE: The input current for a 5500 watt, 48-Volt that is 85% efficient at 44 volts can be calculated as follows:

Ampere Input= (5500 Watts) / (44Vdc x 0.85)= 147Adc

Size Inverter to supply expected continuous load demand. Sum all AC loads which may simultaneously operate from the inverter. Surge Ratings must be capable of starting motor loads such as pumps. Higher Power requirements usually dictate higher DC input voltages to reduce the size of wiring and overcurrent devices required for the inverter.

Project Data

End-User:  NJIT

Installer: LB Electric and IBEW

Location: Newark, NJ

Date of install: June 2004 – Aug. 2004

Size of system in kW: 50kW

Energy produced since installation: +500MWh

Special Challenges Met: Dual Axis Trackers mounted on roof-

Project Brief

New Jersey Institute of Technology (NJIT) is a college campus facility located in Newark New Jersey. NJIT approached TurtleEnergy to design and supply a Photovoltaic System for the new student center building designed by the famous Architect Charles Gwathmey.

This publicly bid Solar Energy project was won by the electrical contractor LB Electric, a minority business enterprise. TurtleEnergy submitted a design to the electrical engineer of record for approval as equal or better to the previously specified system. LB Electric bid and won the installation contract after TurtleEnergy’s design was approved by the Electrical Engineer. LB Electric’s bid was successful in displacing a previously specified system. The bid by LB Electric was significantly lower than the proposed bid by the competitor.

TurtleEnergy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

-Shading Analysis

-Optimal System Design and Concept Planning

-Industrial Design of the Components of the System

-Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers

-Implementation of the owner’s goal for a high visible photovoltaic system

-Instrumentation design for energy performance monitoring

LB Electric used electricians from the IBEW (Local 164) and laborers from the ironworkers union. LB Electric and the International Brotherhood of Electrical Workers completed the project in 3 months (June 2004 – August 2004). (Figure 9) The size of the installed PV system for NJIT is 50kw. TurtleEnergy provided oversight to ensure implementation of the project shop drawings. The complete project team consisted of the following:

Turner Construction (General Contractor)

Gwathmey Siegel & Associates llc (Architect)

Harris Hamnett, PC (Structural Engineer)

A&J Consulting (Electrical Engineer)

LB Electric (Electrical Contractor)

For additional information on product specifications see the appropriate cut sheets listed below.

Wattsun Azimuth Tracker (Array Technologies)

Schott Solar Module: ASE-300-DGF/50 (Schott Solar)

Schott SunRoof FS (Schott Solar)

Schott SunTrack Kiosk (Schott Solar)

StarInverter PVP1800 (PV Powered)

StarInverter PVP2800 (PV Powered)

Project Data

End-User: Lawrenceville School

Installer: Lighton Industries

Location: Lawrenceville, New Jersey

Date of install: May 2012

Size of system in kW: 6000kW

Energy produced since installation: ~27GWh

Special Challenges Met: Environmentally Protected Farming Land

Project Brief

THE LAWRENCEVILLE SCHOOL SOLAR PROJECT

Project Developer: TurtleEnergy LLC,  Date Built: 2012

Client: Sold to KDC Solar

Project: 6MW on thirty acres of single axis trackers, 500kW MV inverters

Cost of project: $28M, Date Energized: May 2012

John Millard's Role- principal in charge/ owner/ primary end user contact.

Civil, environmental, structural, mechanical consultant – Innovative Engineering; Wall, NJ

Permits required- NJDEP; Wetlands LOI, Flood Hazard Applicability Determination. NJ Department of Transportation- Permit to create curb cut on State Road 206. Township of Lawrence Zoning Board- Variance from Environmentally Protected Agricultural Zoning to Commercial Zoning Code. PSE&G interconnection permit, NJCEP SREC permit.

Role by John Millard: 1) Found TurtleEnergy 2003, 2) Sell Company Capabilities to Client in Nov. 2009, 3) Compete with two other companies to win $28M project, 4) Build project team to execute project, 5) Engage and Coordinate Engineering Consultants for Permits, 6) Negotiate Power Purchase Agreement, 7) Provide Due Diligence Design for Lender's Engineer to evaluate and validate for $15M non-recourse financing, 7) Estimate Annual Electricity Production for 20 year Production Guaranty, 8) Evaluate Mounting Hardware solutions for review, 9) Negotiate Procurement Contracts and Project Specific Warranties with Manufacturers of Inverters, Solar Modules, Mounting Hardware and Cable Tray. 10) Lead Site Layout and Subsurface Conduit Route for Permits, 11) Primary Liaison with Client, 12) Primary Legal Negotiator for Developer 13) Expert Witness at Zoning Board of Adjustment Hearing, 14) Negotiate SREC contracts with Load Serving Entities and SREC Brokers.

Project Achieved Zoning Approval in November of 2011 as well as all NJDEP Permits and NJDOT Permits- Project was sold to investors in April of 2011 and construction commenced in October of 2011, energizing in May of 2012 (commercial operations).

John Millard was the principal in charge of this $28M solar PV project. Millard introduced the concept of purchasing electricity from an on-site solar project to the school leadership and led the project development as well as the power purchase negotiations. Millard's company, TurtleEnergy, competed against two other utility scale project companies to win the 9000MWh / Year contract and prevailed.

Millard modelled the annual energy production that he forecast for the the project, communicated the intermittent behavior of the system to the utility and complied with the utility goal of constraining the AC output of the system to 5MW. This was accomplished by deploying a single axis tracker from Array Technologies who supplied the project with state of the art mounting hardware. The electrical design of the project, which was sited one half mile from the point of connection, used medium voltage (12.6kV) transformers to step up the native 200V inverter output in order to minimize line losses and to match the voltage that the utility metered power at the site. The school built a new load center for the campus that was coordinated with the solar electrical power requirements prior to the start of the solar project construction.The shovel ready 6MW solar project was then sold to a private power producer who provided the $28M fund to construct the project.

Schematic Design of The Lawrenceville Solar Project:

Millard formed TurtleEnergy in 2003 in response to the growing world demand for alternative energy solutions to a growing shortage of energy. Together with Millard’s architectural experience and a company called Turtle & Hughes, Inc., they became the nation’s first electrical distributor to form a renewable energy system integration, design & supply company. TurtlEnergy, LLC was founded by Millard and has grown sales of renewable energy systems from a $500,000 in 2004 to over $10,000,000 in 2006. Design and Supply of renewable energy systems is an activity which directly relates to the training which Millard received as an architect due to the highly multi-disciplinary nature of structural, mechanical, civil and electrical engineering coordination required in the renewable energy systems integration business. Hence, Millard formed a team of highly skilled architects & engineers with long histories in the renewable energy industry together with operational specialists within Turtle & Hughes. Prior to the Lawrenceville Project, TurtleEnergy had designed, supplied, construction managed and commissioned over forty solar projects in California, Massachusetts, Pennsylvania and New Jersey.

TurtleEnergy was a company created by John Millard in 2003 to design and supply photovoltaic energy systems to be retrofitted onto commercial buildings.  This activity took place within the constraints of the New Jersey Clean Energy Program and other state programs. This state program was conceived to create incentives for the construction of clean energy systems to produce electricity for businesses and homes in the state of New Jersey.

The Lawrenceville project with the culmination of eight years of business activity by TurtlEnergy which by then had designed over 30 solar electric systems for customers in California, New Jersey, Massachusetts, Pennsylvania, Connecticut and New York.

On-site generation of electricity by utility customers was a relatively new phenomenon on the East Coast. Most solar electric systems interconnected in New Jersey up until January 2010 we're limited to 2 MW AC by the Board of Public utilities in New Jersey. In February 2010, the Board of Public utilities removed the 2MW maximum system size in New Jersey. This regulatory change occurred in the middle of the process of awarding the Lawrenceville project to TurtlEnergy. The increased size of the system could now achieve 6 MW in order to satisfy the entire annual electricity budget of the Lawrenceville School which was 9,500MWh (or 9,500,000KWh- roughly $1M of electricity per year). Virtually tripling the size of the solar project overnight,      The Solar Energy Advancement and Fair Competition Act of 2010 turned our 2MW Solar Project into a 6MW project, an order of magnitude of increased change and economy of scale.

The increased economy of scale by tripling the size of the project not only reduced the unit cost of the project, but also enabled the sale price of electricity to Lawrenceville to be reduced by 40%. The cost of solar panels was still relatively high (compared to 2013 prices) but inverter costs reduced, installation prices reduced, and balance of system prices reduced (wire, mounting hardware, switches, tray, enclosures and other non-Pv components).

The reduction of these costs also helped to consolidate the preferred design option- a single axis tracker mounted PV system which rotated with the altitude of the sun over the course of the day (as opposed to the fixed tilt stationary mount that cost less). 

Schematic Design Issue: Mounting Hardware Selection

There are a number of advantages to the single-axis tracker despite its 5% increased cost to the overall project. Convincing others of this benefit, when they have concerns over the addition of moving parts to the mounting hardware is a challenge. This debate with parent company senior management was topical at the beginning of the project. Essentially, in order to produce the equivalent annual energy of a single axis tracker, one must purchase 15% more solar modules, inverters, mounting hardware and balance of systems to do so. This expenditure alone might silence a critic of moving parts, but there's more- that fixed tilt system redundancy costs to pay for. That 15% larger rated fixed tilt system is going to  produce far less electricity in the morning and late afternoon because of its azimuth angle facing due south. Since the fixed, south facing system makes up for this disadvantage at noon, by producing exponentially more power for an hour or two to make up for its poor morning and afternoon performance. This reality is overlooked when designing smaller systems because of the huge premium that a tracker adds to a small system such as a residential size. This spike of power at noon is accommodated by the utility with smaller systems, but not with Multi MW systems. The utility in the case of the Lawrenceville Project required a 5MW AC cap to the load profile of our design, largely due to the size of the utility wire that served the site. The larger, noon spike of the fixed tilt Pv system resulted in over 150 hours of +5MW operation that would have to be "clipped" or limited using current limitation devices at the point of common coupling in the newly constructed electrical building on the campus. The amount of electricity lost as a result of this clipping was significant enough to diminish any perceived advantage of using a fixed tilt system and the tracker was adopted at schematic design stage of the project. The failure mode analysis of the tracker's moving parts was peer reviewed by Black & Veatch and validated by those venerated engineers as investment grade. Our lender's due diligence engineer, Lahmeyer International also concurred that the tracker made by Array Technologies was "bankable" and the drive motor manufactured by Bonfigliotti was vastly under-employed in the tracker application. Turning the torque tube of mounted modules by one half of one degree every three minutes when it was designed to rotate many hundreds of RPM it seemed to them to be well within the specification of the motor. The slew ring that transferred this tiny rotation into the torque tubes of each module row did have a defective seal in early shipments to early projects in 2006, but this was a quality control problem in the Chinese assembly. All assembly is now in house at Array Technologies in Albuquerque. A site visit to the HQ prior to the $3M purchase of the 6MW tracker proved out the quality. 

Schematic Design Issue: Unforeseen Geotechnical Cost Mitigation:

Regardless of the tracker vs. fixed tilt mount, each of these systems were vulnerable to unforeseen geotechnical risks due to the base case cost assumption that these structures would find favorable ground conditions and the steel posts would be driven freely into the ground using a vibratory pier driver. This method of pier placement requires no concrete and relies on eight to twelve feet of penetration in order to support the lateral load of the wind driven module surface area. If the ground is a "hard dig" situation, it can drastically increase the mounting hardware cost compared to a self-ballasted solution such as Game Change's cast in place system. Our geotechnical study indicated a 20% chance of "pier refusals" which meant that additional equipment and/or concrete footings would be required to solve for the structural spec on each refusal. A pilot hole can be a lowest additional cost, where a drilling rig comes in behind the vibratory pile driver and reems the pier hole to depth and performs a pull out test or, if rocky condition prevail such that a pilot hole is insufficient for the task, then shallow concrete foundations may be the only solution. This is the worst case scenario and can add $100 to $200 per pier. These are the true risks of ground mounted solar, not the moving parts of a single axis tracker. 

Another challenge specific to the single axis tracker is the mid-module mount onto the 4" torque tube. This mount can result in bending the module around the midpoint and cause micro-cracking in the 150 micron thick silicon cells if heavy snowfall settles on the tracked modules while in stow (horizontal) position. Fortunately, thanks to the fact that the range of movement rotates the module every day over 90 degrees, it is impossible for snow to accumulate over more than a 12 hour period. Should 30psf accumulate during that 12 hours during the stowage overnight in horizontal position, then the bracketry that attaches the module to the torque tube must clamp at least 24" of the mid section of the module if the warranty on the module is to be preserved. Most module manufacturers archive an electro-fluoroscopic image of every module that they encapsulate and use this "x-ray" image as proof that the module had no cracks in the cells at shipment. In the case of the Lawrenceville Solar Project, 25,000 solar modules mid-mounted on torque tubes were sufficient cause to request a special project specific written warranty for re-assurance. This the module manufacturer did, and provided it with accompanying failure mode testing documentation of the solar module. The deflection of the module, and the resulting documented micro cracks were clearly defined so that tolerances were understood and engineered for in advance of installing the 6MW project.

Schematic Design Issue: Which is the greater risk? Electrical Risk or Mechanical Risk?

The mechanical opportunities for disaster on a large ground mount are by far more risk than the electrical risks, especially since National Electrical code section for PV has been so thoroughly forged. There have been ground mounted projects that were seamlessly designed and installed but for the near constant 30mph winds year round that induced a harmonic vibration akin to the "galloping girdie" effect that destroyed the Tacoma Narrows Bridge. The tracker manufacturer at Array Technologies had this mechanical risk in mind when he designed into the ends of each module row a hydraulic damper to quash any such movement that might emerge. The rest of the hardware involved with mounting the modules, the module clamps, the viscous couplings that capture the torque tubes, the slew rings, the drive assembly with the universal joints that enable a high degree of tolerance for unruly topography and other components are all well travelled designs from the automotive industry that have generations of predecessors. Even the mechanical component of trenching pipe & wire represents more risk than the electrical nature of the wire itself. Trenching electrical cable from a to b is an irresistible mode of operation for most electrical contractors but in practice, it causes nearly as much congestion and "hard dig" risk in practice and is labor intensive- pure profit for an EC and theoretically easy to estimate cost. Most Electrical Contractors do not automatically opt for cable trays as a substitute for trenching cable. In fact, ground mounted solar power projects are a natural application for cable tray. The long runs of mounting structures are easily suited to suspend tray from piers. Electrical contractors frequently trench right next to the arrays of peers that have been driven into the ground- only to be destabilized buy a 24 inch wide trench being cut inches away from the point where they were driven into the ground. Compaction of these trenches never matches the compaction that existed for that pier prior to a trench being excavated immediately next to it. Additionally, soil conservation districts are now requiring topsoil to be removed if extensive trenching is determined to be necessary for a given solar project in New Jersey. 6 to 12 inches of topsoil to be scraped off the surface of the ground and stockpiled on site-  silt fences and dust control measures have to be implemented by the contractor. Electrical contractors doggedly carry trenching as their primary distribution strategy for large ground mounted solar projects. At the Lawrenceville solar project, total energy specified cable trays to be clamped to the peers which for the linkage columns. These are the columns that have the driveshaft and the slew rings mounted on top. These are larger eight inch columns compared to the 4 inch piers that support the torque tubes of the solar panels. By mounting the cable tray to these columns, the vast majority of cable on the project can be transported above ground without having to excavate 36 inch deep trenches. Cable Tray, in lieu of trenches liberates movement of construction operatives across the site, unhindered by the hazard of open trenches, not to mention the impediment that erosion and mud can cause long term on any construction site. It was shocking to see how little knowledge there was of cable tray code within the electrical engineering discipline at the consultant level. When the owner expressed a preference for cable tray (because of the farmland that was going to be cycled out of production for the 20 year term of the power purchase agreement) our electrical engineer expressed that it would cost $1M to use tray comprehensively across the project (actually the material cost for the tray was $70k). The labor to install cable tray is less than the labor and equipment to excavate trenches (excluding topsoil stockpiling). Then there are all of the other benefits of cable tray- easy maintenance/ commissioning access, less copper per code, less cable, less loose dirt/ mud, and less disruption to free movement on site.

Project Data

End-User: Lawrenceville School

Installer: Lighton Industries

Location: Lawrenceville, New Jersey

Date of install: May 2012

Size of system in kW: 6000kW

Energy produced since installation: ~27GWh

Special Challenges Met: Environmentally Protected Farming Land

Project Brief

THE LAWRENCEVILLE SCHOOL SOLAR PROJECT

Project Developer: TurtleEnergy LLC,  Date Built: 2012

Client: Sold to KDC Solar

Project: 6MW on thirty acres of single axis trackers, 500kW MV inverters

Cost of project: $28M, Date Energized: May 2012

John Millard's Role- principal in charge/ owner/ primary end user contact.

Civil, environmental, structural, mechanical consultant – Innovative Engineering; Wall, NJ

Permits required- NJDEP; Wetlands LOI, Flood Hazard Applicability Determination. NJ Department of Transportation- Permit to create curb cut on State Road 206. Township of Lawrence Zoning Board- Variance from Environmentally Protected Agricultural Zoning to Commercial Zoning Code. PSE&G interconnection permit, NJCEP SREC permit.

Role by John Millard: 1) Found TurtleEnergy 2003, 2) Sell Company Capabilities to Client in Nov. 2009, 3) Compete with two other companies to win $28M project, 4) Build project team to execute project, 5) Engage and Coordinate Engineering Consultants for Permits, 6) Negotiate Power Purchase Agreement, 7) Provide Due Diligence Design for Lender's Engineer to evaluate and validate for $15M non-recourse financing, 7) Estimate Annual Electricity Production for 20 year Production Guaranty, 8) Evaluate Mounting Hardware solutions for review, 9) Negotiate Procurement Contracts and Project Specific Warranties with Manufacturers of Inverters, Solar Modules, Mounting Hardware and Cable Tray. 10) Lead Site Layout and Subsurface Conduit Route for Permits, 11) Primary Liaison with Client, 12) Primary Legal Negotiator for Developer 13) Expert Witness at Zoning Board of Adjustment Hearing, 14) Negotiate SREC contracts with Load Serving Entities and SREC Brokers.

Project Achieved Zoning Approval in November of 2011 as well as all NJDEP Permits and NJDOT Permits- Project was sold to investors in April of 2011 and construction commenced in October of 2011, energizing in May of 2012 (commercial operations).

Summary: 

John Millard was the principal in charge of this $28M solar PV project. Millard introduced the concept of purchasing electricity from an on-site solar project to the school leadership and led the project development as well as the power purchase negotiations. Millard's company, TurtleEnergy, competed against two other utility scale project companies to win the 9000MWh / Year contract and prevailed.

Millard modelled the annual energy production that he forecast for the the project, communicated the intermittent behavior of the system to the utility and complied with the utility goal of constraining the AC output of the system to 5MW. This was accomplished by deploying a single axis tracker from Array Technologies who supplied the project with state of the art mounting hardware. The electrical design of the project, which was sited one half mile from the point of connection, used medium voltage (12.6kV) transformers to step up the native 200V inverter output in order to minimize line losses and to match the voltage that the utility metered power at the site. The school built a new load center for the campus that was coordinated with the solar electrical power requirements prior to the start of the solar project construction.The shovel ready 6MW solar project was then sold to a private power producer who provided the $28M fund to construct the project.

Design Development of The Lawrenceville Solar Project:

The design development phase of the Lawrenceville solar project began as soon as our proposal to the Lawrenceville school was accepted by the committee who was evaluating proposals from three separate solar energy companies. We were notified by the school at Thanksgiving time in 2009 that our proposal had been successfully excepted and that we would now begin the process of negotiating the power purchase contract with the school's attorneys. The primary agreement was determining the price that electricity would be sold to the school from this solar energy system. While we had presented three different options to the school for generating electricity from various types of solar energy systems, the school preferred The single axis tracker option because of the reduced number of solar panels that it would require to generate the same amount of electricity as a solar panel mounted on a fixed tilt system. To representatives of the school the single axis tracker was a balance between the power dense nature of the fix tilt system and the space hungry nature of the dual axis tracker solution. The single axis tracker system would cover approximately the same 30 acres that the fixed till system would require, but it would do so using less solar panels and with a lower ground coverage ratio. This meant that the ground beneath the solar panels would still receive a certain amount of skylight that would enable the agricultural land occupied by the solar project to be rotated out of production of barley and allowed to grow naturally occurring ground covered that would help to restore nutrients to the soil over the 20 year period during which the land would be deployed as a solar farm. This would not be possible with a fixed tilt system largely due to the mechanical nature of the till tracks that would be constructed and the solar panels would not allow sufficient amount of skylight to reach the ground plane in order to allow plants to grow underneath the solar panels. There is far less superstructure underneath the single axis tracker mechanism that there is underneath the till track of a fix tilt solar energy system. The civil engineer involved in the Lawrenceville project presented a range of plant species that would be suitable to grow under the single axis trackers and yet would require a minimum amount of mowing. Lawrenceville engaged a sustainability consultants who recommended wildflowers that would sustain many colonies of bees that could be located in hives at the site. It was thought that by cultivating honeybees at the site and growing forage under the single axis trackers that the school might be able to retain its agricultural assessment for tax purposes at the local level.
Hence the schematic design agreed-upon at the turn of the year in 2009 was a 30 acre land deployment of single axis trackers mounted single module in portrait orientation with a .5 ground coverage ratio, with vegetative ground cover inside the fence that would be suitable for honeybee forage, and that the design should require The minimum amount of excavation of the agricultural land so as not to disturb the topsoil across the 30 acre parcel. The exact method of power distribution and the types of inverters and the size of the housekeeping pads and other detailed aspects of the design would be solved during the periods of time during which the power purchase agreement would be negotiated to hammer out the details of the production guarantee, the land lease, termination defaults, and many other specific terms that would be determined over the eighth month that it required to negotiate the power purchase agreement. These terms and many of the detailed design considerations of the solar project would be resolved during the design development phase of the project.

In early 2010 the selection of a manufacturer for the single axis tracker to be deployed at the Lawrenceville project was the first priority. Within the family of single axis tracker manufacturers there are a couple of distinguishing fundamental attributes that one became familiar with the first being what method of actuation was deployed in order to move the solar panels. This boils down to essentially two methods- central actuation and distributed actuation. What this means is that some single axis tracker manufacturers deploy a smaller, separate motor to drive movement on each separate group of solar panels numbering 20 or less. Other manufacturers deploy a larger, central motor to drive movements on each separate group of solar panels numbering 200 or more. Each manufacturer claims merit for each philosophy – distributed actuation manufacturers claim that by distributing many smaller motors across a single axis tracked solar project that there is less risk of a motor failing and causing a loss of energy to the project. Central actuation manufacturers claim that the motor that they deploy to drive 200 or more solar panels is vastly under-employed compared to applications for which that larger motor was designed. They maintain that their larger motor is reliable and durable – with demonstrated failure mode analyses with an acceptably low risk of failure. Those companies predisposed to central actuation, also point to the fact that each motor requires a supply of AC electricity usually 120 V.  This requirement vastly increases the electrical scope of work for any distributed actuation solar project. Larger, centrally actuated motors require only one AC power supply for one motor where as a distributed actuation project would require 10 times as many power supplies. Many people think that the electricity for these smaller motors can come from the solar power- and that is a misconception. Even if it were true, it would still represents a significant increase in labor to wire a separate motor for every 20 solar panels on the project. Another challenge of having 10 times as many motors on a tracker project is the fact that you then also must design for 10 times as many separately moving torque tubes. It stands to reason that if you have one motor driving one tortilla to rotate from morning tonight that the torque tube must then be independent of other rotating torque tubes that are driven by separate motors. This aspect to distributed actuation is perhaps the most agree just design feature because each separately moving torque tube must be supported by a separate structure. While this may at first not seem to be a major liability of the design, it soon becomes evident on a project where there is even the slightest change in grade over distance that each structure causes a redundancy in the number of peers that are required to adjust for the change in grade. A centrally actuated torque tube can be infinitely long and is limited in length only by the strength of the motor. Since there is only one torque tube that is being rotated by this motor, this torque tube can continue to slope with the ground and be housed within an infinite number of viscous couplings that are simple to support, inexpensive, and commonly found on the shelves of hardware suppliers. Only the strength of the motor limits the length of the torque tube thereby eliminating any need for number of articulate joints required to separate disparate moving torque tubes required by distributed actuation tracker projects. Finally, in order to monitor the functionality of each separate motor, a exponential increase in the amount of communications electronics required to monitor those motors is required with distributed actuation tracker projects. Therefore, distributed actuation projects require separate AC power supplies for each motor, separate communications for each motor, separate mechanical structures to support each separately rotating torque tube and separate, distinct motors each having its own maintenance requirements and failure mode.

Our company discovered all of these attributes of each actuation philosophy by visiting manufacturers in the United States. We embarked on this mission thinking that distributed actuation was the preferable strategy. We returned from this mission convinced that central actuation was by far the cheapest and simplest solution to moving solar panels in the sun. Reaching this conclusion was the source of a great deal of consternation on our project team. Some thought that by doing diligence on these mechanical systems – we were demonstrating a knowledge blind spot that disqualified us from determining how to design the solar project. Naturally these members of senior management including exclusively finance related team members declared that the solar project should become a fixed tilt design and that the single axis tracker effort should be abandoned. According to them, the moving parts factor was already beginning to sabotage our solar project! A strengths, weaknesses, opportunities and threats (SWOT) analysis was then initiated by our team to put to death the debate about fixed versus tracked solar once and for all. Bottom line, a fixed tilt system would require 15% more solar panels, more mounting hardware, more inverters, and more land than a single axis tracker that produced the same amount of electricity per year. This metric was undeniable and despite that, the finance team persisted in their preference for a fixed tilt system and engaged in politics to achieve that outcome. A board meeting of the parent company was convened and concerns expressed about the "moving parts factor" of the $28 million project. The additional cost of building 15% more project was presented to the board as an acceptable cost in order to reduce the risk that the single axis tracker might not move properly. A financial wizard was deployed with pro forma spreadsheet to show how these additional costs could be "present valued" or amortized over the 20 year term of the power purchase agreement. Senior management omniscience pervaded this discussion, there was also a dismissal of the concerns that the larger, fixed tilt design would violate the utility's 5 MW AC cap resulting in the shedding of 150 peak hours of production per year- a loss of significant amount of electricity in order to comply with the utility's directive. After the meeting, the board members all hopped into their cars – each with hundreds of moving parts and drove to lunch.

Ultimately, the single axis tracker was adopted as the basis of design for the Lawrenceville solar project. The centrally actuated tracker manufactured by Array Technologies of Albuquerque, New Mexico was chosen as the preferred solution. This outcome was the result of several closed-door "seminars" with senior management that properly examined the due diligence exercise that created a rational, process of elimination of the distributed actuation trackers, presented third party failure mode analysis by Black & Veach, recommended quantities of attic storage parts and their cost, as well as the history of successful single axis tracker projects by Array Technologies of Albuquerque, New Mexico. Subsequently, disaffected finance team members left the company and the project over their fears of moving parts. At the time of writing, the project has been in service for over two years. The project has survived two hurricanes with minimal disruption caused only by the discontinuation of electrical service from the utility for a period of 10 days during hurricane Sandy. Excessive snowfall during these two years of 2013 and 2014 has demonstrated the superior performance of the single axis tracker during winter months with the ability to tilt the solar modules by 45°, thus causing the snowfall to be removed from the solar panels at discretion. Similar fixed tilt systems in the region continued to be covered by residual snowfall for a period of weeks, resulting in a significant loss of electricity. This unanticipated benefits of being able to control the angle of tilt was discovered in early 2013. Both the Lawrenceville School and the owner of the solar project are very happy with the decision to build a single axis tracker instead of a fixed tilt solar project.
Design development issue: How to get the electricity from the farmland to the campus across 2500 feet of golf course and wetlands.
Short answer: Directional drilling and lots of SEPA permitting.

The obstacles that were thrown at the project were sometimes self-inflicted and other times inflicted by regulatory issues well defined by the State of New Jersey's State Environmental Protection Act. There were not only wetlands that separated the agricultural field (where the solar project was to be cited) from the campus electrical load center, nearly 1/2 mile away, but there was also a small lake that directly interfered with the electrical umbilical that would travel underground from point a to point b. This threat was exacerbated by early advice given by the consulting civil engineer for the project that we would be able to daylight the cable across an existing footbridge that traversed the stream that discharged from this small lake. Months later in the project, the civil engineer discovered that the entire area surrounding the lake was also classified as a wetland – traversable only by using directional drilling.

Directional drilling, a technology perfected by the oil and gas industry – has now been adopted by the electrical contracting industry to solve for difficult trenching conditions. In this case, an ecologist was employed to survey the elevation of the freshwater stream that was the epicenter of the wetland. This survey helped to determine what, if any, flood hazard applicability determination should be assessed for this site. While flood hazard applicability does not affect the method of trenching or directional drilling, it does affect the long-term integrity of the trench if it is to be affected by rising water. Therefore it was a combination of the extent of the wetlands species that were discovered on the site as well as the extent of the floodplain that was calculated by the hydrology engineers engaged by the project that determined how many feet of directional drilling was required to evade the obstacle presented by the wetland. In the end, a directional drilling run of 550 feet was required to travel under the wetland and the floodplain in order to be considered a negative determination of impact. This 550 foot tunnel beneath the lake also preserved the golf course and other landscape that was environmentally sensitive to trenching. The flood hazard applicability determination permit was launched with the state of New Jersey at the end of April 2010 and was not permitted until early August 2010. Meanwhile, the power purchase agreement negotiations between the parties was still not complete. Costs to complete all of the manufacturing due diligence as well as the environmental permits for the project were accumulating into a seven-figure number.

Project Data

End-User: Lawrenceville School

Installer: Lighton Industries

Location: Lawrenceville, New Jersey

Date of install: May 2012

Size of system in kW: 6000kW

Energy produced since installation: ~27GWh

Special Challenges Met: Environmentally Protected Farming Land

Project Brief

THE LAWRENCEVILLE SCHOOL SOLAR PROJECT

Project Developer: TurtleEnergy LLC,  Date Built: 2012

Client: Sold to KDC Solar

Project: 6MW on thirty acres of single axis trackers, 500kW MV inverters

Cost of project: $28M, Date Energized: May 2012

John Millard's Role- principal in charge/ owner/ primary end user contact.

Civil, environmental, structural, mechanical consultant – Innovative Engineering; Wall, NJ

Permits required- NJDEP; Wetlands LOI, Flood Hazard Applicability Determination. NJ Department of Transportation- Permit to create curb cut on State Road 206. Township of Lawrence Zoning Board- Variance from Environmentally Protected Agricultural Zoning to Commercial Zoning Code. PSE&G interconnection permit, NJCEP SREC permit.

Role by John Millard: 1) Found TurtleEnergy 2003, 2) Sell Company Capabilities to Client in Nov. 2009, 3) Compete with two other companies to win $28M project, 4) Build project team to execute project, 5) Engage and Coordinate Engineering Consultants for Permits, 6) Negotiate Power Purchase Agreement, 7) Provide Due Diligence Design for Lender's Engineer to evaluate and validate for $15M non-recourse financing, 7) Estimate Annual Electricity Production for 20 year Production Guaranty, 8) Evaluate Mounting Hardware solutions for review, 9) Negotiate Procurement Contracts and Project Specific Warranties with Manufacturers of Inverters, Solar Modules, Mounting Hardware and Cable Tray. 10) Lead Site Layout and Subsurface Conduit Route for Permits, 11) Primary Liaison with Client, 12) Primary Legal Negotiator for Developer 13) Expert Witness at Zoning Board of Adjustment Hearing, 14) Negotiate SREC contracts with Load Serving Entities and SREC Brokers.

Project Achieved Zoning Approval in November of 2011 as well as all NJDEP Permits and NJDOT Permits- Project was sold to investors in April of 2011 and construction commenced in October of 2011, energizing in May of 2012 (commercial operations).

Design development issue: The Lawrenceville School's 60-year-old Electrical Load Center- would this aged electrical infrastructure be able to accommodate over 1200 A of solar power or not?
One of the obligations that the Lawrenceville school faced under the solar power purchase agreement with TurtlEnergy was the need to maintain a functional electrical room with infrastructure capable of receiving a significant amount of electricity from the sun farm. If for some reason this aged infrastructure were to break down, the Lawrenceville School would be responsible for any loss of power purchase that was delivered to the point of common coupling by the sun farm. There were other risks that the Lawrenceville School faced if they were going to persist with this 60-year-old electrical room that was the campus's nerve center for electrical power. The catastrophic disruption of electrical power to the campus would affect the hundreds of boarding students and day students who attended class in side the campuses classrooms. The question was: How was the school going to be able to pay for a new million dollar electrical center for the campus? The answer was: a gift from Henry Woods, an English teacher who served the school over a long period of time who had recently passed away bequeathed tens of millions of dollars to the school, just as this critical need was identified. 
The school engaged electrical engineers to design the new electrical building that would be located in an extension to the old power plant which had served the school for 60 years. Prior to this 60 year old powerplant being constructed, it was not uncommon for students to use candles and hurricane lamps with whale oil to study at night. With the age of the Lawrenceville school being 100 years, the school was celebrating it's Centenary in 2010. The construction of the solar project was a centerpiece of this Centenary celebration. The construction of a state-of-the-art switchgear room to serve as the school's new load center was an expense that was conveniently absorbed by this enormous gift from Henry Woods. Nevertheless, the new load center became a critical path milestone in the schedule to complete the solar project. The school's electrical engineers and the electrical contractor employed to construct the load center where under pressure to provide date certainty that an electrical breaker sufficient unto the task of accommodating the 1200 Amps of power from the sun would be complete in time to perform under the power purchase agreement. The design was coordinated with the electrical engineers designing the solar energy system, the construction contract was executed with an electrical contractor and construction began late 2010. The utility agreed to provide a new service cable to the school as part of their obligations to provide utility power to the school and their construction coincided with the new load center's construction. As it would turn out, the utility also needed to upgrade the fuses on the utility poles that protected the utility infrastructure from short-circuits on the campus. These fuses were not replaced until after the solar project had tripped them several times causing a black out to the entire campus after the system was energized in May 2012. Subsequently, the fuses were upgraded and the project has been exporting power onto the grid routinely at levels that comply with the utilities 5 MW AC for the project. This electrical risk was unforeseen by the project team and was considered a force majeure event covered by force majeure language in the power purchase agreement concerning availability of utility power. Therefore neither party was to blame for the loss of revenue created during these relatively short disruptions to the supply of electricity to the campus.

Ultimately, the impetus created by the solar project caused for the creation of a brand-new electrical load center to be constructed for the campus. Additionally, over 1100 feet of utility service cables were replaced at the same time that the new load center was constructed. With the completion of the solar project, 90% of the electrical infrastructure that would serve the solar project with connectivity was completely new. This fact created a great deal of comfort for both the buyer of the power and the seller of the power under the Lawrenceville power purchase agreement.

Design Development Issue: The availability of sunlight to the solar panels over time.

In determining the site coverage for the solar project there were some assumptions made about the availability of sunlight over the 20 year term of the power purchase agreement. One assumption was that the construction of any tall antenna like structure such as cell towers or other structure should be memorialized as prohibited by the buyer in the power purchase agreement. There also was concerned that the growth of trees along the eastern and western boundary of the site should be managed by the buyer over the course of the term. In order to quantify the height that was tolerated by the design of the solar energy system, site sections were drawn, bagels were defined, and contingencies were described. The growth of trees especially along the western boundary of the project which bordered the golf course and the campus was of primary concern to both parties. The school, for their part – wished to allow these trees to be grown unfettered by any topping activity or other trimming that might result in an unsightly boundary to the campus as a result of the solar projects rights of light. The solar project allocated a 130 foot shading buffer to exist between the westernmost solar panels and this vegetative buffer with the campus that had trees which exceeded 50 feet in height. The eastern boundary of the solar project was also defined by a vegetative buffer, but with much less developed, unhealthy trees that had apparently been trimmed by farmers over the years who wished to preserve the availability of sunlight for the crops that crew due west of this vegetative buffer. The design of the solar project allowed a 100 foot buffer to exist between the easternmost solar panels and this vegetative buffer with the adjoining owner, a third party farming entity. The shadows caused by these vegetative buffers to the east and the west of the solar project had already created a considerable loss of power for the solar project. All solar projects face certain obstacles on the horizon that cause for shading issues in the early morning and in the late afternoon. With a single axis tracker which tilts the modules towards the east in the morning and towards the west in the afternoon there is already a built in sheeting issue that is caused by self-feeding of the solar panels upon each other. The effect of self shading at these times of the day is mitigated by an algorithm designed into the tracking mechanism's programmable logic controller called "backtracking". What this algorithm does is it trains the solar panels to remain in a horizontal orientation in the early hours of the day as well as the late hours of the day in order to avoid creating shadows upon each other. As the sun rises in altitude and the risk of self shading diminishes, the algorithm trains the solar panels to exactly tilt so that the low altitude sun rises and the shadow that would otherwise cause the self shading of one solar panel upon another is avoided while a certain tilt angle is maximized in order to increase electricity production at these times of the day. Therefore, even if there were no obstructions on the horizon of the earth, a single axis trucker creates its own obstructions and therefore is less sensitive to low obstacles on the horizon such as these 55 foot high vegetative buffers to the east and to the west. It is also worth noting that such obstacles only remain an obstacle for a very short period of time in the morning and in the evening because of the rapid ascent and descent of the sun at these altitudes. Therefore, the team optimized the site coverage with the 130 foot buffer to the west and the 100 foot buffer to the east and was comfortable with this design which was memorialized in exhibit K of the power purchase agreement.

Design development issue: Choosing to use cable tray to distribute DC electrical power and control power to the tracker motors project wide.

As was discussed briefly in the schematic design issues of the Lawrenceville solar project, the advantages of using cable tray to distribute DC electrical power and AC control power to the tractor motors and other instrumentation are briefly revisited here below:

- Cable Tray is used in many projects where its flexiblility, cost, ease of access to conductors, labor friendliness and tendency to allow other more flexible solutions to other challenges such as combiner box locations, wire transitions from mounting hardware into combiner boxes and inverters with side entry opportunities.

- Use of cable tray eliminates 95% of trenching, conduit, and equipment required to excavate trenches. In fact, at nearly $5 per foot, these eliminations from the construction budget must be subtracted from the cost of tray which typically amounts to $5 to $10 per linear foot. The cost of pulling wire may be equated to the cost of laying wire in tray, but in fact, pulling wire is much more labor intensive than tray layout. There are other savings to be had with cable tray- and that is the savings in copper that there is to recover when applying the open air thermal resistivity coefficient to PV wire sizing- both for home uns to boxes and for larger conductors returning to DC recombiners. Tray provides a valuable route to which small control power conductors in conduit can be clipped onto the side of tray in order to separately deliver AC power to devices on the inverter pad, tracker motors or security devices.

- There is of course, the opportunity to mount combiner boxes on tray and that savings over free standing vertically mounted boxes is  equal to the full value of all concrete, excavation, and strut assemblies which amount to several hundred dollars per box. (not to mention the loss of conduit, elbows, couplings and labor associated with stubbing up.

- The back mounting of combiner boxes on tray is an electrician’s idea. The transitions from tray to box requires only a minute devation of angle for a Sealitite segment to steer conductors right through the side of the box, into the fuse holders, terminal blocks and grounding lugs. Grounding is easy with tray since the tray itself is used as a grounding conductor provided that jumpers are installed at each tray splice.

- The proximity of back mounted boxes to their respective source circuits, by nature, minimizes wirelength, improves efficiency of the system design and costs less for copper. The access to the box is from the top and allows for direct skylight to illuminuate the interior of the box. With the door sealed properly with a neopreme weather strip, NEMA 3R boxes are permissible where a NEMA 4 box might otherwise be called for.

- The Cable Tray acts as a bi-directional super highway for DC conductors to travel from source circuits to combiner boxes and from combiner boxes to inverter DC recombiners. Tray also is usefull for projects where there is a non-whole number of strings in a row of modules and a jumper is neccessary to complete a string. That jumper can ride on tray (and be shorter, easier to wire and visible) to and from one row to the other row without having to go underground.

- True, above ground distribution is an inconvenience for the lawn mower, but the improved site circulation, lack of mud, lack of fall hazards, reduced number of heavy equipment vehicles and other  effects of“trenched earth” are conspicuously absent on a site where cable tray is the rule for wire management, not the exception to the rule.

- Electricians space conductors in tray in order to benefit from the open air temperature coefficient that reduces the amount of copper required to acheive the same circuit resistance calculation as a conductor in a conduit in a trench buried under utility sand, warning tape, clear fill, top soil and landscaping because of the heat that the conductor emits inside the conduit. Savings on copper alone can amount to $1,000 to $5,000 per MW DC. In this case, the electricians are segregating the inverter home runs to the one side of the tray so that they can freely fill the other side of the tray with the smaller sub-array wiring (which is not by code required to be spaced apart). They may install a separator to insure that the smaller conductors to not creep over onto the the larger conductors which require complete expsure to fresh air according to NEC.

- Cable Tray can span up to 20’ and remain cost effective for solar projects. The project above has the tray (pictured) spanning 13’ from one mounting hardware  column to another. The tray is supported by a bracket that can be procured from any number of vendors. The bracket detail shown on the detail below is suitbale for a schedule 80 steel pipe that supports a torque tube slew ring. In this case availability of a vertical support for the cable tray is provided by the mounting hardware.

- Depending on the application, whether by tracker, fixed tilt, carport, roof mount or pole mount- cable tray opportunities to gain free support off of mounting structure often seem to be available for scrutiny, resolution and execution. The best support for a cable tray is often the ballast block that comes with the mounting solution and often it is the driven pier that has been cleared by the structural engineer to act as a dual purpose solution.

- The ability of tray to collect conductors from under solar panels is perhaps overlooked as so often we see projects pulling hundreds of feet of cable through conduit and loading those conduit runs on pipe piers and requiring the additional labor to install thermal expansion joints, couplings, elbows and other fittings just to deliver a few pairs of #10 wire to a combiner box. Cable tray is a reliable, durable alternative to conduit and a superior cable management system compared to “trenched earth”.

Project Data

End-User: East Coast Warehouse

Installer: Forest Electric

Location: Port Elizabeth, New Jersey

Date of install: September 2006

Size of system in kW: 700kW

Energy produced since installation: 1.4GWh

Special Challenges Met: Building Integrated Photovoltaics

Project Brief

There are several PV system performance analysis tools that are routinely used to predict the energy production of photovoltaic power systems.  Possibly the most commonly used tools are Clean Power Estimator and PV Watts.  Of these two, the PV Watts program usually produces a lower estimate, compared to the Clean Power Estimator.  Input variables for these software tools include geographic location, historic weather data bases, tilt angle, azimuth, soiling factors, inverter efficiency and system wiring losses.  However, all of these programs are based on the performance characteristics of crystalline photovoltaic panels.  Therefore, in order to accurately predict the performance of thin-film photovoltaic power systems, adjustments must be made.  Also, aside from the measured characteristics of the crystalline photovoltaic panels and the calculated tilt of the array, the other variables are subject to approximations based on “best guess” estimates.

It is a well-established fact that the triple-junction, thin-film, amorphous silicon photovoltaic panels produce more electrical energy per watt than crystalline photovoltaic panels.  This is primarily due to the following factors:

-Less than ½ the cell temperature de-rating compared to crystalline silicon PV (better performance at high cell temperatures)

-Higher efficiencies at low light levels, diffused light, and low-angle light

-Less affected by soiling and shading factors

Over the past several years, many comparative studies have been done to both verify and quantify this significant difference in energy production performance.  Attached are a series of independent technical papers and associated documents that are examples of the published results of these tests and analyses.

The first is A Real World Examination of PV Systems Design and Performance presented at the 2005 IEEE Photovoltaic Specialist Conference.  This paper documents the results of a year-long test that compares the performance of crystalline and thin-film technologies on a single roof in Santa Cruz, CA.  The data shows that the Uni-Solar Thin-film system (sloped arrays) produced 20% more energy than an identically sized crystalline system.  It also showed that a zero-slope Uni-Solar array produced as much energy as the sloped crystalline array of equal size.

The second paper is Superior Energy Yields of Uni-Solar Triple-Junction Thin Film Silicon Solar Cells compared to Crystalline Silicon Solar Cells under Real Outdoor Conditions in Western Europe, presented at the European Photovoltaic Solar Energy Conference in 2001.  As the title of the paper indicates, the thin-film technology is a superior energy producer when compared to crystalline silicon PV.  In this study, a total of 14 different systems were compared in several western European locations to illustrate, with overwhelming data, that in real-world conditions, even in a less-than-optimum solar environment, the thin-film product was superior.

The third paper is Flat roof integration from the Swiss Federal Office of Energy Annual Report for 2004.  In section 3.3 of this paper (Energy Production), it is noted that the performance of the Uni-Solar PV array was as much as 30% greater than the predicted energy output. 

The fourth paper, Performance Analysis of Large Scale, Amorphous Silicon Photovoltaic Power Systems, presented at the 2005 IEEE Photovoltaic Specialist Conference, examines two years of performance data from the first 500kW thin-film PV power system installed in the US.  The key point of this study is the verification of the consistent, better-than-predicted, performance of a large scale Uni-Solar PV system.  This system was designed and installed by a prominent crystalline PV power system company as a 500kWAC system.  It turned out that the superior performance of the thin-film array has produced measured power outputs of 540kWAC, 8% more than had been expected from the same size crystalline system.

The last set of pages are a collection of charts and graphs that are made up of performance data from crystalline and thin film systems.  Each one illustrates and demonstrates the significant performance differences at different light levels and temperature levels as well as system performance data from actual systems throughout Europe.   The stated conclusion is that for the cases addressed, the Uni-Solar arrays produced from 15% to 35% more energy than crystalline arrays.

The over-all conclusion of these and several other reports is that the predicted energy output in kilowatt-hours, for any crystalline PV system will be 10% to 30% less than a thin-film system of the same rated capacity in watts.

Project Data

End-User: East Coast Warehouse

Installer: Forest Electric

Location: Port Elizabeth, New Jersey

Date of install: September 2006

Size of system in kW: 700kW

Energy produced since installation: 1.4GWh

Special Challenges Met: Building Integrated Photovoltaics

Project Brief:

Project Data

End-User: East Coast Warehouse

Installer: Forest Electric

Location: Port Elizabeth, New Jersey

Date of install: September 2006

Size of system in kW: 700kW

Energy produced since installation: 1.4GWh

Special Challenges Met: Building Integrated Photovoltaics

Project Brief

TEST AND COMMISSIONING PROCEDURE FOR 700KW PHOTOVOLTAIC POWER SYSTEM

East Coast Warehouse, Port Elizabeth, NJ

SECTION #1

1.1 Introduction

1.2  Safety Warnings- PV Laminates

2.3  Safety Warnings – SatCon Inverters (PCS)

SECTION #2

2.1 Initial Test and Commissioning of Solar Arrays

2.2 Inverter System (PCS) Operation and Start-up

SECTION #3

3.1 Maintenance                 

SECTION #4

4.1 Check lists                                               

COMMISSIONING PROCEDURE

SECTION #1

1.1. Introduction

The photovoltaic power system installed on the East Coast Warehouse building at 1140 Polaris Street, Elizabeth, NJ, is a building-integrated, 700kW DC system.  The major system components are as follows:

(5,148)   Uni-Solar PVL-136 Photovoltaic Laminate solar panels

(36)        12-channnel combiner boxes

(12)        3-Pole, 200A, 600V, DC Disconnect Switches – fused

(3)          SatCon 225kW, 480VAC Inverter/transformer power conditioning systems

(3)          3-phase, 400A, 480VAC AC Disconnect Switches - fused

The system electrical architecture is shown in the diagram below:

As shown in the above system block diagram, there are three, identical, 225kWAC subsystems that make up the complete system.  The Single-Line Electrical Diagram that describes each 225kWAC subsystem is shown below:

The 5,148 flexible, thin-film, photovoltaic panels are adhered directly to the standing seam metal roofing pans on the roof of the building.  They are arranged in electrical series strings of 12-panels each for a combined string operating voltage of 396VDC.  The string operating current is a maximum of 4.1A, under full sun (1,000 watts per square meter).  This current varies from zero to 4.1A depending on the solar energy striking the surface of the photovoltaic panels.

The strings are paralleled in each of 36, 12-channel combiner boxes for a total maximum current of 49.2A at the operating voltage of 396VDC.  The maximum short-circuit current in each string is 5.1ADC.  The combined short circuit current for each combiner box and DC Disconnect circuit is 61.2A.  This means that the maximum current that can exist in any circuit on the DC side of the system is 61.2ADC feeding a direct short circuit.  The maximum operating DC current in any DC circuit is 49.2A feeding the inverter as its operating load.  The output of the inverter system is 480VAC, three-phase.  The maximum AC current that can be delivered by each inverter is 270A.

Summary of operating voltages and currents:

Array Operating Voltage (Vmp)                                396VDC

Array Maximum Open Circuit Voltage (Voc)             554.4VDC

Array String Current (Imp)                                        4.1A

Array String Short Circuit Current (Isc)                     5.1A

Combiner Box Current (12-string) (Imp)                   49.2A

Combiner Box Short Circuit Current (Isc)                 61.2A

Inverter AC Output Voltage (Nominal)                      480VAC

Inverter AC Output Current (at rated output)            270A

NOTES:

During the first 8-10 weeks of operation, electrical output exceeds specified ratings.  Power output may be higher by 15%, operating voltage may be higher by 11% and operating current may be higher by 4%.

Electrical specifications (±5%) are based on measurements performed at standard test conditions of 1000 W/m2 irradiance, Air Mass 1.5, and Cell Temperature of 25°C after long-term stabilization.  Actual performance may vary up to 10% from rated power due to low temperature operation, spectral and other related effects.

Manufacturer has tested array string sizes up to 14 panels in extreme cold conditions without measuring an actual Voc greater than 600V.

1.2 Safety Warnings – PV Laminates

The UNI-SOLAR Field Applied PV laminates produce DC electricity when exposed to the sun or other light sources.  The power from one individual panel is not considered hazardous.  However, when connected in series and/or connected in parallel, the potential shock hazard increases.   In this case, the string voltage is near 400VDC.

Observe safe electrical practices at all times.  Use insulated tools.

Observe safety precautions when accessing and walking on the roof.  Avoid standing closer than 6’ from the edge of the roof.  Do not walk on wire covers.

Make sure that all sources of electrical current have been disconnected prior to servicing or altering the electrical wiring connections.  There are often multiple sources feeding a single point.

Avoid dropping any sharp objects on solar PV laminates.

Avoid standing on the PV laminates whenever possible.  If unavoidable, wear clean, soft-soled shoes and walk in the center of the panel. CAUTION!!  Laminates are very slippery when wet.

1.3 Safety Warnings – SatCon Inverters (PCS)

The PCS contains lethal voltages.  All power switches should be opened and inverter ES switch placed in the “OFF” position prior to opening the cabinet doors.  To avoid the potential of electrical shock, do not open cabinet doors until 5 (five) minutes after disconnecting all sources of supply.

An incorrectly installed PCS may result in equipment damage or a reduction in product life.  Incorrect wire sizing, inadequate supply, or excessive ambient temperatures may result in system malfunction.

The PCS units contain ESD (Electrostatic Discharge) sensitive parts and assemblies.  Static control precautions are required when installing, testing servicing or repairing these units.

The PCS enclosure contains exposed high voltage conductors.  The enclosure door should remain locked, except during maintenance or testing by service personnel.  To avoid the potential of electrical shock, do not open cabinet doors until 5 (five) minutes after disconnecting all sources of supply.

Improper phase connections, paralleling, or use of the PCS can damage the equipment.  Precautions should be taken to ensure that the PCS units have been properly installed.

SECTION #2

Initial Test and Commissioning

Turn-off (Open) all DC and AC disconnect switches located in the building electrical room.  Open all AC and DC disconnect switches on Inverters A, B, & C.

Visual Check of roof surface

Examine the surface of the roof to verify the following:

No significant debrisSolar panels are adhered and arranged in straight rows (north-south).Wire covers are arranged in straight rows (north-south)

2.1.3   □Visual Check of mounting brackets for DC combiner boxes

Observe that the combiner boxes are securely mounted to the Uni-Strut brackets

Observe that the mounting assemblies are secured to the standing seam roofing

2.1.4   □Visual check of all PV panel interconnections

With wire cover assembly lids removed, perform a visual check of PV panel strings and sub-array wiring.  Wiring is to be one pair of “home-run” wires from each 12-panel string to the appropriate combiner box.   Note:  USE-2 Wire, which is rated for external, surface wiring applications with exposure to water, oil, and UV, is used as the standard PV panel wiring.  In this case, a wire cover is implemented for convenience and aesthetics.

2.1.5   □Open string circuit fuses

Open the door of each of the 36 combiner boxes and ensure that the pop-up fuse holders are all in the “open” position.  With a voltmeter, check for open circuit voltage on each array string (far left set of wire connections at each of the 12 fuse holders).  Open circuit voltage should be greater than 450VDC and should be within 20V of each other on a string-to-string basis.  Record the measured voltage for each PV string.  (Checklist Worksheet in Section 4)

2.1.6   □Check combiner box connections

Visually check the electrical connections in each combiner box for proper wire connections.  Red wires from PV array should be connected to the fuse blocks and black wires should be connected to the negative lug(s).  With the fuses in the “open” position, check the positive and negative connections at the output of each combiner box for tightness (no specific torque spec.).

2.1.7   □Check combiner box ground connection

Verify that the green ground wire is connected the combiner box ground lug.

2.1.8   □Check DC Disconnect terminals

With the Combiner Box fuses in the “open” position, open each DC Disconnect Switch covers and check all electrical connections in each of the twelve, DC disconnect switches.  Tightening torque on these electrical connections should be 55 to 65 foot-pounds.

2.1.9   □Close Combiner box fuses

Place all DC Combiner Box fuses in the “closed” position.

2.1.10   □Check DC disconnect connections

Make sure all DC Disconnect Switches are in the “off” position with the covers open.  With a voltmeter, check the open circuit PV array voltage at each lug, near the top of all 12 DC disconnect switches. The measured voltages between the positive and negative terminals should be consistent with the voltages measured at the combiner boxes.  Record the measured open circuit voltage at each lug while all switches are in the open position.  (Checklist Worksheet in Section 4)

2.1.11   □Check connections & torque at re-combiner panel

Open the cover of the DC input re-combiner panel.  (see photos on page 14) Visually check all connections.  Ensure that the DC disconnect switches are in the “open” position.  Check the torque on each of the twelve +DC input lugs and –DC input lugs in the re-combiner panel.  Torque should be consistent with those shown in Table 2.1

2.1.12   □Close DC Disconnect Switches

Close each DC Disconnect individually and check for the open circuit voltage at the corresponding terminals in the inverter re-combiner panel.  Verify that the markings on the DC Disconnects are consistent with the connections in the inverter re-combiner panel.  There are four DC Disconnects connected to each of the three inverters and three array circuits (combiner boxes) per DC Disconnect.  Measure and record the DC voltage measurements at each.  (Checklist Worksheet in Section 4)

2.1.13   □Open AC disconnects

Make sure that all three AC Disconnect Switches are in the “Off” position.  The AC Disconnect Switches are wired directly to the building main bus so that side of the switch terminals will be “hot”.

2.1.14   □Check AC power connections visually

Open disconnect switch cover and visually check all AC power connections at each AC Disconnect Switch.  Open the AC input cover on the left end of the inverter and check the three-phase connections between the inverter and the AC Disconnect Switch (see photo on page 15).  Torque should be consistent with values shown in Table 2.1. 

2.1.15   □Check AC fuses

Make sure that the 300A AC Fuses are in place and properly secured.

2.1.16     □Check AC connections at inverter (torque)

Torque should be consistent with those shown in Table 2.1

2.1.17     □Check ground connections (torque)

Check all earth ground connections.  Torque should be consistent with those shown in Table 2.1

TABLE 2.1 – Torque Specifications for SatCon Inverter

2.1.18  □Close AC disconnects

2.2  Inverter System (PCS) Operation and Start-up

Note:  Please read the Operating Instructions before proceeding with the Initial Power Up steps.

Initial Power Up – Repeat for each of three inverters

Close AC Breaker CB1Wait 10 seconds for processor initialization and check the voltage displayed on the display screen (use OIT, Main Menu-Metering-AC Line).Check that the unit is not faulted (use OIT, Main Menu-Diagnostics-Next Fault).Check that the unit is testing the grid (use OIT, Main Menu-Page Down-Page Down).Close the DC Disconnect Switch DS1.Check that the PCS is displaying the PV voltage correctly (use Main Menu-Metering-DC PV).Check that the unit is checking the DC input voltage (use Main Menu-Page Down-Page Down).Check tha the PCS is in ENABLE condition (Main Menu-Operation); in case it is not in ENABLE condition, use Page Down from the same screen, position the promper on the PCS EN/DIS line, press CLEAR, edit “1”, and press ENTER.  Use again Page Down to go to the next screen SAVE SETTINGS, press CLEAR, edit “1”, and press ENTER.

2.2.1 Operating Instructions

This section describes the operating instructions and the sequence of events of PCS operation. The PCS can be operated either from the local control panel OIT or from a PC through modbus communication between the PC and the PCS Digital Control Board.

2.2.2 General

The power conditioning system follows the line frequency and the voltage set by the utility while delivering power to load. The PCS is designed for rated power and performance at +/-10% of the nominal line voltage and +/-2% line unbalance voltage.

The PCS meets or exceeds the requirements of IEEE 519-1992 Standard for voltage and current power quality.

The unit operates as AC current controlled voltage-source inverter. The inverter is synchronized with the phase of the line voltage automatically through controlling the current reference signal, which is synchronized with the line. This allows the control of power factor, real power and reactive power.

The PCS adjusts the reactive power to the line as per the KVAR or reactive current demand signal. Real and reactive power accuracy is within +/-2% of the rated demand.

In the case that voltage and/or frequency of the line becomes less than or more than the specified range, the unit stops and is disconnected from the line and the PV arrays. The Voltage & Frequency Output Protection is provided by the PCS digital control board DPCB, tested by UL to UL1741 standards.

2.2.3 PCS Operating States

The PCS has the following operating states:
a) Sleep Unit is stopped, contactors are open, no fault.
b) Pre-drive PCS pre-charges and regulates the DC link voltage.
c) Drive PCS is running. During this state the PCS generates real power to the grid by tracking the maximum power point of the PV or follows AC active current settings that are set from the OIT. Meanwhile, the PCS also controls AC reactive power by reactive power setting that is set from either the OIT or the remote communication.
d) Fault -Unit critical fault, PCS will shutdown and can only be reset manually.

2.2.4  PCS Control

2.2.4.1 Enable/Disable the PCS

The PCS has a setting for Run enable or disable. PCS can be enabled or disabled from the local controller OIT or the remote communication command. When the PCS is disabled, it cannot run. The default setting when the logic powers up can only be changed from the local OIT.

2.2.4.2 Start the PCS

When all of the following conditions are satisfied, the PCS will start automatically.

1)  The PCS is in Sleep state (i.e. no fault).

2)  The PCS is enabled.

3)  The grid is OK that means the voltage and frequency of the grid has been within specification for more than 5 minutes.

4)  The DC input voltage has been higher than a minimum voltage (VDC1-MINIM can be set from OIT) for more than 30 minutes (VDC1-MIN TM can be set from OIT) or higher than a higher threshold voltage (VDC1-TH can be set from OIT) for more than 10 minutes (VDC1-TH TM can be set from OIT).

The following describes the sequence of events during starting of the PCS:

1)  PCS closes the AC charging contactor (ACM) and the pre-charge action will take place. PCS enters into Pre-drive state. If the DC link voltage does not reach pre-charge value within 30 seconds, the unit will fault out as a Pre-charge fault .

2)  After 10 to 30 seconds, DC link capacitors are charged. PCS closes AC contactor CR2 .

3)  After 2 seconds, Pre-charge contactor ACM is opened.

4)  After 3 seconds, PCS enables gating to the inverter and Power Generating LED on the front door starts flashing. PCS will regulate DC link voltage to 350Vdc.

5)  After 5 seconds, PCS starts to regulate DC link voltage to DC input voltage plus 10Vdc.

6)  After 5 seconds, PCS closes DC contactor CR1A .

7)   After 2 seconds, PCS enters into Drive state. PCS will regulate DC link voltage and DC input current to track maximum power point if MPPT is enabled or PCS will follow DC link voltage command and AC active current command if MPPT is disabled.

2.2.4.3 Stop the PCS

Any one of the following events will stop the PCS and the PCS will go in Sleep state.

1)  Fault(s)

2)  PCS Disable – Command is provided from the local controller (OIT) or the remote controller

3)  PCS detects a line fault (i.e. line over/under voltage or frequency specification

4) DC input voltage is lower than its limit.

5) DC input current has been zero for longer than 32 seconds (IDC-IN-ZERO can be set from OIT) when the PCS is in Drive State

6) AC output real power has been negative (i.e. PCS receives power from the grid) for longer than 30 minutes (KW-LINE-TM can be set from OIT) when the PCS is in Drive State

The following describes the sequence of events during stopping the PCS:
1) Inverter gating will be stopped.
2) Contactors CR1A & CR1B and CR2 open to isolate the PCS from the PV and the grid.
3) PCS goes into Sleep State

What has caused the last stop can be seen in the OIT Main Menu Operation screen.

2.2.5 Fault Shutdown of the PCS

Note that all the faults are latched and can be reset from the local or remote controller.

The following describes the sequence of events during fault shutdown:

1)   Inverter gating will be stopped.
2)   Contactors CR1A & CR1B and CR2 open to isolate the PCS from the PV and grid.
3)   PCS is in Fault State

4)   The PCS faults are displayed in the OIT Main Menu Diagnostic screen.

2.2.6 E-Stop of the PCS

The Emergency Stop can be generated from the local E-Stop push button on the door of the PCS or from the remote communication command.
The following describes the sequence of events during E-STOP:
1) Inverter gating will be stopped.
2) Contactors CR1A & CR1B and CR2 open to isolate the PCS from the PV and grid.
3) PCS is in Fault State.

2.2.7 Reset the PCS

When the PCS is in Fault State, it needs to be reset. Resetting the PCS can be done from the local controller OIT or from the remote communication command.

DC INPUT RECOMBINER PANEL

INVERTER AC INPUT TERMINALS

3.0  Maintenance

3.1 Care of PV Laminates on Steel Roofing Pans

If parts of the solar panels become separated from the metal roofing pans, clean the roofing pan surface under the part of the solar panel that has lifted and apply a black, roofing adhesive caulk.  Carefully press the solar panel into the adhesive caulk.   Use a J-Roller to apply even pressure over the separated area.

Project Data

End User: Newark Park High School

Installer: Railroad Electric

Location:Newark, NJ

Date of Install: Nov 2005 - April 2006

Size of System in kW: 30

Project Developer: TurtleEnergy

Special Challenges Met: Architect’s design.

Complete Project Team:                       

Electrical Engineer: EYP Electrical Engineers

Architect: EYP Architects                       

Structural Engineer: EYP Structural Engineers

Project Brief:

TurtleEnergy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers (Stellar Energy Solutions)

The project commenced in May of 2006 and was successfully completed

The building and PV system was designed by architects

Einhorn Yaffee Prescott. The design of the PV system underwent some modifications by Turtle Energy. The PV system was finally built Sept 2006 through November 2006. This was some 2 years after being originally bid, in the meantime the module  manufacturer Astropower had been boughtout by GE. However Turtle Energy provided a service to the contractor such that the system was built without a hitch.

The Newark Board of Eduction put out to bid the entire process of building  Newark Science Park High School. The Photovoltatic system was one of these individual bids. Turtle Energy  provided a system quote and expertise to enable RCC Electric to win the bid for the PV system.  Newark Science Park High School is a 250,000-s.f. magnet science, mathematics, and technology high school that will serve as a model for urban school districts in New Jersey and throughout the country. TurtleEnergy excels at designing photovoltaic (PV) arrays so that efficiency is optimized for both the dimensions and orientation of the given area and costs are kept to a minimum. Project design and planning services by TurtleEnergy’s designers and managers yields over 50 years of cominbed experience. TurtleEnergy ensures that each system is performing to the maximum potential at the end of each installation. Measuring power output from each sector of the photovoltaic array is part of TurtleEnergy’s distinguishable service to its end users. From the start of the Newark Science Park High School project, TurtleEnergy’s designers determined optimal opportunities to generate electricity at the point of use, transforming a relatively unused space into a useful source of revenue. TurtleEnergy continues to ensure that the system is performing at its optimal level long after the installation has been completed via its remote energy monitoring system that is checked on a daily basis at TurtleEnergy’s headquarters. Ongoing measurement of the energy production is a key hallmark of TurtleEnergy and differentiates it as a full service renewable energy company. Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented for the Newark Science Park High School project. The Fat Spaniel data acquisition system, logs the actual energy generation by the PV system. The resulting measurements are in compliance with the predicted analysis done by TurtleEnergy. The Fat Spaniel system data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. For additional information on product specifications see the appropriate cut sheets listed below.

Ballard 30kw Inverter

Shell 165w Powermax

Solarmount mounting hardware

Fat Spaniel (remote monitoring system)

Project Data

End-User: The Center for Neurodevelopmental Disabilities

Installer: Evco Mechanical

Location: Bloomfield NJ

Date of install: February 2005

Size of system in kW: 18kW

Energy produced since installation: 180MWh

Special Challenges Met: Self-Ballasted Mounting Hardware

Project Brief:

Project Data

End-User: Private Residence

Installer: Electrician

Location: Lebanon, NJ

Date of install: July 2005

Size of system in kW: 10kW

Energy produced since installation: ~200MWh

Special Challenges Met: Battery Interactive and Grid Interactive System

Project Brief:

Project Data:

End-User: Washington Gas

Installer: Martifer Solar USA

Location: Maynard, Ma. Landfill Site

Date of install: April 2013

Size of system in kW: 1200kW

Energy produced since installation: approximately 2,800MWh as of 2/2015

Special Challenges Met: Entire design requires no penetrations through landfill cap.

Project Brief:

John Millard was hired by Martifer Solar in November of 2012 to manage four utility scale solar projects in New England, the Maynard Landfill Solar project was one of these projects. 

Millard hired the the four project teams that would execute the four designs produced by Martifer Solar USA project engineers in LA. Millard oversaw the design of each project and managed the production of construction documents for each design except for the Southbridge project which had already been designed by the time of his joining Martifer in November 2012. Of the four solar projects, three of the projects were located on landfill sites. The Maynard Massachusetts project and the Brookfield Massachusetts project both required designs that would not penetrate the landfill. This required that all electricity distribution for the solar project would utilize code compliant cable tray design and self ballasted mounting hardware for the solar support structure. s was discovered at the Southbridge Massachusetts project, New England soils are typically shallow and represent hard dig conditions. Application engineers ignore this fact of life at their peril.

In the case of the Southbridge Massachusetts project, soil depth issues were already preventing extensive trenching to code-compliant depth across the 3.4 MW Solar project construction site. One of the first corrective actions that Milard was responsible for implementing was a change order that solved for the failure to place over 500 lineal feet of DC conductors in code compliance trenches. The solution was to create concrete duct bank that would lie on top of the shallow hardpan and deliver the PVC conduit from the combiner boxes to the inverter pads. This change order required extensive field measurements and coordination with the engineers in LA in order to institutes a properly documented change.

With the Brookfield and Maynard projects, both landfill projects with restrictions from penetrating the landfill cap, Millard was able to incorporate cable trays into the design for these two projects prior to the start of construction. This enabled the designers to freely distribute DC electrical power where ever it was possible to site self ballasted solar support structure on top of the landfill. This also enabled the designers to reduce the size of the electrical conductors due to the fact that they were air cooled in the cable tray according to national electric code. Other benefits to using cable tray are described in the memo below: 

Re:  Coordination of Cable Management with Geotech Report...

Has anyone asked the question why we always trench? Here are some downsides to trenching:

Heavy equipment rental costs & dangers, Spoils may contaminate topsoil, Labor to trench is $4.25 - $4.50 / LF, Unforeseens in the ground pose risks, Passing these risks onto contractor is costly., Conduit must be purchased with all attendent fittings, couplings, expansion jts, etc., Resistivity calulations are more heat intensive resulting in more Copper / Aluminum due to heat premium, More length requ’d to transition in / out of ground, More length- more pipe, more labor, more IR loss, More permit risk of env. cost (stockpiling farm soil), Open Trenches restrict movement of site ops, Restrictions of movement cost time / create danger, Erosion issues, Additional OSHA triggers, Landscaping repairs, costs, requirements by AHJ, Difficult to access/ change or repair, Leaks Water/ Damages Cable, The following memo is an illustration of how a project in New England- a place with shallow rocky soil can surprise the veteran PV designer with setbacks that exponentially revise up costs and duration. The Pilgrims and the origins of the Thanksgiving Holiday are truths to be told, Future landfill projects here in New England will dictate that all wire management occur above grade. There will be no trenching on these projects allowed per SEPA. Now is the time to explore options to “trenched earth”, Crystalized: if the Geotech report says there is no soil for a 24” deep trench, find another method of distributing wires around your solar project.

    Challenge Statement: Designers under extreme pressure to print construction issues sometimes make mistakes. These mistakes have to be rectified on site by project managers and construction managers without the benefit of quick decision making processes available to designers- rather than rectifying some vector graphics and text blocks on a cad drawing, PMs & CMs have their sub-contracted partners on the project uncovering unconstructible designs and submitting RFIs, and Change Orders after careful study of the problem. The the Martifer CM / PM team have to convince Design Staff that there is a constructibility problem with the drawing. Depending on the disposition of the designer, the process of realizing the problem can take a while to acceptance.

    Once the designer has accepted the constructiblility challenges of the original construction plan or detail, there is the solution phase. This phase may not take place quickly or, worse, there may be a delay to the solution for all kinds of  other reasons related to change process within Martifer or related to the reluctance to initiate change by other parties in the internal change process. Many times the designer who has accepted the original “mistake” may find acknowledging the original “mistake” as an occuptional hazard and delay or distract the processing of the change.

    This memo looks at a specific technical issue related to underground surprises. The observations made on site have concluded that the original design was not constructible, and there are photographs that show a soil dept that makes it clear- a code compliant conduit trench was indeed not possible to be constructed at this site without the use of dynamite. Pick axes, sledge hammers and pneumatic hammers would not prevail in the conditions at this site in order to deliver the original detail that was drawn on a piece of paper. Some have suggested that the electrical contractor should have detected these conditions in the Geotechnical Report. The good news is that the mounting hardware designer must have, as clearly evidenced by the large, precast concrete ballast blocks:

    While using this “Braille” approach to discovering the extent of the shallow soil, constuction continued at breakneck pace on all aspects of the design, including the inverter pads- The PM & CM were communicating their findings to Martifer and seeking guidance on the solution to this problem of how to cover the conduits for DC distribution on the east side of the site with a code compliant amount of cover... 

    The electrical contractor immediately recommended cable tray to the PM. This suggestion was rejected by Martifer and another solution was proposed- concrete duct bank. This would be cast over the pvc conduits and covered with clear fill. The PM was instructed to obtain a bid for the placement of at least 4” of cast-in-place concrete over the top of the concduit. But how much shallow conduit would be manually determined to require this solution to accurately describe the scope and quantity of the concrete? The trencher had to keep trenching and inspections for shallow trench conditions would have to be made before a drawing that showed the extent of the shallow conditions could be issued to the concrete contractor. This process took a great deal of time.

    As construction continued, new shallow soil challenges emerged such as how to transition from conduit in the proposed concrete duct bank into the inverter since the inverter pads also sat on shallow soil conditions. The drawings had called for bottom entry of the conduits into the DC recombiner and the AC compartments in the inverter. Unfortunately, the concrete ductbank solution for the conduits assumed that the conduits would eventually find their way to deeper soil and consequently to the inverter pad, where they would dive under the pad and emerge through the bottom entry in the inverter. This was not to be the case...another constructibility issue requiring a change order.

Pad details show bottom entry to inverter from trench...

Now that the conduits are to be encased in concrete on the surface of the hardpan, and the inverter pad also sits on the surface of the hardpan, there is no way for the conduits to transition up, into the inverter recombiner through the inverter pad for two reasons;

They are at the same level as the bottom of the slab.

Unless the slab is built up with hundreds of yards of concrete in order to allow sufficient height for the 90 degree transitions to occur under the slab, the conductors have no way to get into the DC compartment nor is there room for the AC conductors to egress the AC compartment to leave the pad and reach the adjoining MV Transformer with a similar bottom entry:

    How to stub up in shallow soil condition?

    Now the PM / CM team on site see the limitations of the concrete encased conduits as far as: how to enter the inverter? Side entry seems likely, but how to transition out of the duct bank to enter the side of the inverter? If they had adopted the cable tray solution presented by the electrical contractor, they would have avoided a great deal of shallow trenching, wire pulling and now concrete encasing. Had tray been adopted, there would still have been concrete duct bank required for maintenance vehicular circulation over the wire runs.

Cable Tray is the more flexible solution for utility scale:

Transition from tray into conduit for vehicle over passes...

Cable Tray is used in many projects where its flexiblility, cost, ease of access to conductors, labor friendliness and tendency to allow other more flexible solutions to other challenges such as combiner box locations, wire transitions from mounting hardware into combiner boxes and inverters with side entry opportunities.

Cable Tray side entry capability for inverter service...

On utility scale projects where agricultural land is environmentally protected, local zoning committees are reluctant to permit multi-MW projects because of the damage that extensive trenching causes to the top soil. In some cases they have required topsoil to be scraped off the surface of the ground to a depth of 12 “ and stockpiled, only later to be re-distributed by the civil contractor after the trenching has completed the process of backfilling the spoils into the trenches. Needless to say this is an expensive additional cost of trenching:

Environmentally protected farmland is often topsoil focused and costly topsoil management is triggered by trenching when this could be avoided by using cable tray.

Use of cable tray eliminates 95% of trenching, conduit, and equipment required to excavate trenches. In fact, at nearly $5 per foot, these eliminations from the construction budget must be subtracted from the cost of tray which typically amounts to $5 to $10 per linear foot. The cost of pulling wire may be equated to the cost of laying wire in tray, but in fact, pulling wire is much more labor intensive than tray layout. There are other savings to be had with cable tray- and that is the savings in copper that there is to recover when applying the open air thermal resistivity coefficient to PV wire sizing- both for home uns to boxes and for larger conductors returning to DC recombiners. Tray provides a valuable route to which small control power conductors in conduit can be clipped onto the side of tray in order to separately deliver AC power to devices on the inverter pad, tracker motors or security devices.

NEMA 3R HOFFMAN BOXES W 12 CIRCUITS EA MOUNTED ON THEIR BACKS ON TRAY AND INSPECTED ALL DAY LONG...

    There is of course, the opportunity to mount combiner boxes on tray and that savings over free standing vertically mounted boxes is  equal to the full value of all concrete, excavation, and strut assemblies which amount to several hundred dollars per box. (not to mention the loss of conduit, elbows, couplings and labor associated with stubbing up.

Side Entry Service for Inverters is accessible and saves a lot of subslab coordination, setting out, and mess on site...

The back mounting of combiner boxes on tray is an electrician’s idea. The transitions from tray to box requires only a minute devation of angle for a Sealitite segment to steer conductors right through the side of the box, into the fuse holders, terminal blocks and grounding lugs. Grounding is easy with tray since the tray itself is used as a grounding conductor provided that jumpers are installed at each tray splice.

   TYPICAL TRANSITION FROM MOUNT TO TRAY...NO PIPE

The proximity of back mounted boxes to their respective source circuits, by nature, minimizes wirelength, improves efficiency of the system design and costs less for copper. The access to the box is from the top and allows for direct skylight to illuminuate the interior of the box. With the door sealed properly with a neopreme weather strip, NEMA 3R boxes are permissible where a NEMA 4 box might otherwise be called for.

ELECTRICIANS ROUTINELY INSTALL BOXES ON THEIR BACKS

The Cable Tray acts as a bi-directional super highway for DC conductors to travel from source circuits to combiner boxes and from combiner boxes to inverter DC recombiners. Tray also is usefull for projects where there is a non-whole number of strings in a row of modules and a jumper is neccessary to complete a string. That jumper can ride on tray (and be shorter, easier to wire and visible) to and from one row to the other row without having to go underground.

    ELECTRICIANS PREFER THE STRAIGHT ENTRY INTO BOX.

Using smaller boxes is a benefit when mounting to tray not only because the tray width is limited (in this case to 12”) but also because circuits travel shorter distances to smaller boxes. True, above ground distribution is an inconvenience for the lawn mower, but the improved site circulation, lack of mud, lack of fall hazards, reduced number of heavy equipment vehicles and other  effects of“trenched earth” are conspicuously absent on a site where cable tray is the rule for wire management, not the exception to the rule.

THIS CABLE TRAY WILL CARY 250KW WORTH OF DC CIRCUITS

    Electricians space conductors in tray in order to benefit from the open air temperature coefficient that reduces the amount of copper required to acheive the same circuit resistance calculation as a conductor in a conduit in a trench buried under utility sand, warning tape, clear fill, top soil and landscaping because of the heat that the conductor emits inside the conduit. Savings on copper alone can amount to $1,000 to $5,000 per MW DC. In this case, the electricians are segregating the inverter home runs to the one side of the tray so that they can freely fill the other side of the tray with the smaller sub-array wiring (which is not by code required to be spaced apart). They may install a separator to insure that the smaller conductors to not creep over onto the the larger conductors which require complete expsure to fresh air according to NEC.Cable Tray can span up to 20’ and remain cost effective for solar projects. The project above has the tray (pictured) spanning 13’ from one mounting hardware  column to another. The tray is supported by a bracket that can be procured from any number of vendors. The bracket detail shown on the detail below is suitbale for a schedule 80 steel pipe that supports a torque tube slew ring. In this case availability of a vertical support for the cable tray is provided by the mounting hardware.

DETAIL SHOWING SEPARATE TRAYS FOR SUB-ARRAY WIRING AND INVERTER HOME RUNS, RUNG SPACING DIFFERS PER TRAY.

Depending on the application, whether by tracker, fixed tilt, carport, roof mount or pole mount- cable tray opportunities to gain free support off of mounting structure often seem to be available for scrutiny, resolution and execution. The best support for a cable tray is often the ballast block that comes with the mounting solution and often it is the driven pier that has been cleared by the structural engineer to act as a dual purpose solution.

CABLE TRAY ON THE ROOF OF AN ELEMENTARY SCHOOL...

The ability of tray to collect conductors from under solar panels is perhaps overlooked as so often we see projects pulling hundreds of feet of cable through conduit and loading those conduit runs on pipe piers and requiring the additional labor to install thermal expansion joints, couplings, elbows and other fittings just to deliver a few pairs of #10 wire to a combiner box. Cable tray is a reliable, durable alternative to conduit and a superior cable management system compared to “trenched earth”.

Project Data:

End-User: Washington Gas

Installer: Martifer Solar USA

Location: Brrokfield, Ma. Landfill Site

Date of install: April 2013

Size of system in kW: 600kW

Energy produced since installation: approximately ~800MWh as of 2/2015

Special Challenges Met: Entire design requires no penetrations through landfill cap.

Project Brief:

John Millard was hired by Martifer Solar in November of 2012 to manage four utility scale solar projects in New England, the Maynard Landfill Solar project was one of these projects. 

Millard hired the the four project teams that would execute the four designs produced by Martifer Solar USA project engineers in LA. Millard oversaw the design of each project and managed the production of construction documents for each design except for the Southbridge project which had already been designed by the time of his joining Martifer in November 2012. Of the four solar projects, three of the projects were located on landfill sites. The Maynard Massachusetts project and the Brookfield Massachusetts project both required designs that would not penetrate the landfill. This required that all electricity distribution for the solar project would utilize code compliant cable tray design and self ballasted mounting hardware for the solar support structure. s was discovered at the Southbridge Massachusetts project, New England soils are typically shallow and represent hard dig conditions. Application engineers ignore this fact of life at their peril.

With the Brookfield and Maynard projects, both landfill projects with restrictions from penetrating the landfill cap, Millard was able to incorporate cable trays into the design for these two projects prior to the start of construction. This enabled the designers to freely distribute DC electrical power where ever it was possible to site self ballasted solar support structure on top of the landfill. This also enabled the designers to reduce the size of the electrical conductors due to the fact that they were air cooled in the cable tray according to national electric code. Other benefits to using cable tray are described in the memo below: 

Re:  Coordination of Cable Management with Geotech Report...

as anyone asked the question why we always trench? Here are some downsides to trenching:

Heavy equipment rental costs & dangers, Spoils may contaminate topsoil, Labor to trench is $4.25 - $4.50 / LF, Unforeseens in the ground pose risks, Passing these risks onto contractor is costly., Conduit must be purchased with all attendent fittings, couplings, expansion jts, etc., Resistivity calulations are more heat intensive resulting in more Copper / Aluminum due to heat premium, More length requ’d to transition in / out of ground, More length- more pipe, more labor, more IR loss, More permit risk of env. cost (stockpiling farm soil), Open Trenches restrict movement of site ops, Restrictions of movement cost time / create danger, Erosion issues, Additional OSHA triggers, Landscaping repairs, costs, requirements by AHJ, Difficult to access/ change or repair, Leaks Water/ Damages Cable, The following memo is an illustration of how a project in New England- a place with shallow rocky soil can surprise the veteran PV designer with setbacks that exponentially revise up costs and duration. The Pilgrims and the origins of the Thanksgiving Holiday are truths to be told, Future landfill projects here in New England will dictate that all wire management occur above grade. There will be no trenching on these projects allowed per SEPA. Now is the time to explore options to “trenched earth”, Crystalized: if the Geotech report says there is no soil for a 24” deep trench, find another method of distributing wires around your solar project.

    Challenge Statement: Designers under extreme pressure to print construction issues sometimes make mistakes. These mistakes have to be rectified on site by project managers and construction managers without the benefit of quick decision making processes available to designers- rather than rectifying some vector graphics and text blocks on a cad drawing, PMs & CMs have their sub-contracted partners on the project uncovering unconstructible designs and submitting RFIs, and Change Orders after careful study of the problem. The the Martifer CM / PM team have to convince Design Staff that there is a constructibility problem with the drawing. Depending on the disposition of the designer, the process of realizing the problem can take a while to acceptance.

    Once the designer has accepted the constructiblility challenges of the original construction plan or detail, there is the solution phase. This phase may not take place quickly or, worse, there may be a delay to the solution for all kinds of  other reasons related to change process within Martifer or related to the reluctance to initiate change by other parties in the internal change process. Many times the designer who has accepted the original “mistake” may find acknowledging the original “mistake” as an occuptional hazard and delay or distract the processing of the change.

    This memo looks at a specific technical issue related to underground surprises. The observations made on site have concluded that the original design was not constructible, and there are photographs that show a soil dept that makes it clear- a code compliant conduit trench was indeed not possible to be constructed at this site without the use of dynamite. Pick axes, sledge hammers and pneumatic hammers would not prevail in the conditions at this site in order to deliver the original detail that was drawn on a piece of paper. Some have suggested that the electrical contractor should have detected these conditions in the Geotechnical Report. The good news is that the mounting hardware designer must have, as clearly evidenced by the large, precast concrete ballast blocks:

    While using this “Braille” approach to discovering the extent of the shallow soil, constuction continued at breakneck pace on all aspects of the design, including the inverter pads- The PM & CM were communicating their findings to Martifer and seeking guidance on the solution to this problem of how to cover the conduits for DC distribution on the east side of the site with a code compliant amount of cover... 

    The electrical contractor immediately recommended cable tray to the PM. This suggestion was rejected by Martifer and another solution was proposed- concrete duct bank. This would be cast over the pvc conduits and covered with clear fill. The PM was instructed to obtain a bid for the placement of at least 4” of cast-in-place concrete over the top of the concduit. But how much shallow conduit would be manually determined to require this solution to accurately describe the scope and quantity of the concrete? The trencher had to keep trenching and inspections for shallow trench conditions would have to be made before a drawing that showed the extent of the shallow conditions could be issued to the concrete contractor. This process took a great deal of time.

    As construction continued, new shallow soil challenges emerged such as how to transition from conduit in the proposed concrete duct bank into the inverter since the inverter pads also sat on shallow soil conditions. The drawings had called for bottom entry of the conduits into the DC recombiner and the AC compartments in the inverter. Unfortunately, the concrete ductbank solution for the conduits assumed that the conduits would eventually find their way to deeper soil and consequently to the inverter pad, where they would dive under the pad and emerge through the bottom entry in the inverter. This was not to be the case...another constructibility issue requiring a change order.

Pad details show bottom entry to inverter from trench...

Now that the conduits are to be encased in concrete on the surface of the hardpan, and the inverter pad also sits on the surface of the hardpan, there is no way for the conduits to transition up, into the inverter recombiner through the inverter pad for two reasons;

They are at the same level as the bottom of the slab.

Unless the slab is built up with hundreds of yards of concrete in order to allow sufficient height for the 90 degree transitions to occur under the slab, the conductors have no way to get into the DC compartment nor is there room for the AC conductors to egress the AC compartment to leave the pad and reach the adjoining MV Transformer with a similar bottom entry:

    How to stub up in shallow soil condition?

    Now the PM / CM team on site see the limitations of the concrete encased conduits as far as: how to enter the inverter? Side entry seems likely, but how to transition out of the duct bank to enter the side of the inverter? If they had adopted the cable tray solution presented by the electrical contractor, they would have avoided a great deal of shallow trenching, wire pulling and now concrete encasing. Had tray been adopted, there would still have been concrete duct bank required for maintenance vehicular circulation over the wire runs.

Cable Tray is the more flexible solution for utility scale:

Transition from tray into conduit for vehicle over passes...

Cable Tray is used in many projects where its flexiblility, cost, ease of access to conductors, labor friendliness and tendency to allow other more flexible solutions to other challenges such as combiner box locations, wire transitions from mounting hardware into combiner boxes and inverters with side entry opportunities.

Cable Tray side entry capability for inverter service...

On utility scale projects where agricultural land is environmentally protected, local zoning committees are reluctant to permit multi-MW projects because of the damage that extensive trenching causes to the top soil. In some cases they have required topsoil to be scraped off the surface of the ground to a depth of 12 “ and stockpiled, only later to be re-distributed by the civil contractor after the trenching has completed the process of backfilling the spoils into the trenches. Needless to say this is an expensive additional cost of trenching:

Environmentally protected farmland is often topsoil focused and costly topsoil management is triggered by trenching when this could be avoided by using cable tray.

Use of cable tray eliminates 95% of trenching, conduit, and equipment required to excavate trenches. In fact, at nearly $5 per foot, these eliminations from the construction budget must be subtracted from the cost of tray which typically amounts to $5 to $10 per linear foot. The cost of pulling wire may be equated to the cost of laying wire in tray, but in fact, pulling wire is much more labor intensive than tray layout. There are other savings to be had with cable tray- and that is the savings in copper that there is to recover when applying the open air thermal resistivity coefficient to PV wire sizing- both for home uns to boxes and for larger conductors returning to DC recombiners. Tray provides a valuable route to which small control power conductors in conduit can be clipped onto the side of tray in order to separately deliver AC power to devices on the inverter pad, tracker motors or security devices.

NEMA 3R HOFFMAN BOXES W 12 CIRCUITS EA MOUNTED ON THEIR BACKS ON TRAY AND INSPECTED ALL DAY LONG...

    There is of course, the opportunity to mount combiner boxes on tray and that savings over free standing vertically mounted boxes is  equal to the full value of all concrete, excavation, and strut assemblies which amount to several hundred dollars per box. (not to mention the loss of conduit, elbows, couplings and labor associated with stubbing up.

Side Entry Service for Inverters is accessible and saves a lot of subslab coordination, setting out, and mess on site...

The back mounting of combiner boxes on tray is an electrician’s idea. The transitions from tray to box requires only a minute devation of angle for a Sealitite segment to steer conductors right through the side of the box, into the fuse holders, terminal blocks and grounding lugs. Grounding is easy with tray since the tray itself is used as a grounding conductor provided that jumpers are installed at each tray splice.

   TYPICAL TRANSITION FROM MOUNT TO TRAY...NO PIPE

The proximity of back mounted boxes to their respective source circuits, by nature, minimizes wirelength, improves efficiency of the system design and costs less for copper. The access to the box is from the top and allows for direct skylight to illuminuate the interior of the box. With the door sealed properly with a neopreme weather strip, NEMA 3R boxes are permissible where a NEMA 4 box might otherwise be called for.

ELECTRICIANS ROUTINELY INSTALL BOXES ON THEIR BACKS

The Cable Tray acts as a bi-directional super highway for DC conductors to travel from source circuits to combiner boxes and from combiner boxes to inverter DC recombiners. Tray also is usefull for projects where there is a non-whole number of strings in a row of modules and a jumper is neccessary to complete a string. That jumper can ride on tray (and be shorter, easier to wire and visible) to and from one row to the other row without having to go underground.

    ELECTRICIANS PREFER THE STRAIGHT ENTRY INTO BOX.

Using smaller boxes is a benefit when mounting to tray not only because the tray width is limited (in this case to 12”) but also because circuits travel shorter distances to smaller boxes. True, above ground distribution is an inconvenience for the lawn mower, but the improved site circulation, lack of mud, lack of fall hazards, reduced number of heavy equipment vehicles and other  effects of“trenched earth” are conspicuously absent on a site where cable tray is the rule for wire management, not the exception to the rule.

THIS CABLE TRAY WILL CARY 250KW WORTH OF DC CIRCUITS

    Electricians space conductors in tray in order to benefit from the open air temperature coefficient that reduces the amount of copper required to acheive the same circuit resistance calculation as a conductor in a conduit in a trench buried under utility sand, warning tape, clear fill, top soil and landscaping because of the heat that the conductor emits inside the conduit. Savings on copper alone can amount to $1,000 to $5,000 per MW DC. In this case, the electricians are segregating the inverter home runs to the one side of the tray so that they can freely fill the other side of the tray with the smaller sub-array wiring (which is not by code required to be spaced apart). They may install a separator to insure that the smaller conductors to not creep over onto the the larger conductors which require complete expsure to fresh air according to NEC.Cable Tray can span up to 20’ and remain cost effective for solar projects. The project above has the tray (pictured) spanning 13’ from one mounting hardware  column to another. The tray is supported by a bracket that can be procured from any number of vendors. The bracket detail shown on the detail below is suitbale for a schedule 80 steel pipe that supports a torque tube slew ring. In this case availability of a vertical support for the cable tray is provided by the mounting hardware.

DETAIL SHOWING SEPARATE TRAYS FOR SUB-ARRAY WIRING AND INVERTER HOME RUNS, RUNG SPACING DIFFERS PER TRAY.

Depending on the application, whether by tracker, fixed tilt, carport, roof mount or pole mount- cable tray opportunities to gain free support off of mounting structure often seem to be available for scrutiny, resolution and execution. The best support for a cable tray is often the ballast block that comes with the mounting solution and often it is the driven pier that has been cleared by the structural engineer to act as a dual purpose solution.

CABLE TRAY ON THE ROOF OF AN ELEMENTARY SCHOOL...

The ability of tray to collect conductors from under solar panels is perhaps overlooked as so often we see projects pulling hundreds of feet of cable through conduit and loading those conduit runs on pipe piers and requiring the additional labor to install thermal expansion joints, couplings, elbows and other fittings just to deliver a few pairs of #10 wire to a combiner box. Cable tray is a reliable, durable alternative to conduit and a superior cable management system compared to “trenched earth”.

Project Data:

End-User: Washington Gas

Installer: Martifer Solar USA

Location: Orange, Ma. Landfill Site

Date of install: April 2013

Size of system in kW: 2400kW

Energy produced since installation: approximately 3,800MWh as of 2/2015

Special Challenges Met: Entire design requires no penetrations through landfill cap.

Project Brief:

John Millard was hired by Martifer Solar in November of 2012 to manage four utility scale solar projects in New England, the Maynard Landfill Solar project was one of these projects. 

Millard hired the the four project teams that would execute the four designs produced by Martifer Solar USA project engineers in LA. Millard oversaw the design of each project and managed the production of construction documents for each design except for the Southbridge project which had already been designed by the time of his joining Martifer in November 2012. Of the four solar projects, three of the projects were located on landfill sites. The Maynard Massachusetts project and the Brookfield Massachusetts project both required designs that would not penetrate the landfill. This required that all electricity distribution for the solar project would utilize code compliant cable tray design and self ballasted mounting hardware for the solar support structure. s was discovered at the Southbridge Massachusetts project, New England soils are typically shallow and represent hard dig conditions. Application engineers ignore this fact of life at their peril.

In the case of the Southbridge Massachusetts project, soil depth issues were already preventing extensive trenching to code-compliant depth across the 3.4 MW Solar project construction site. One of the first corrective actions that Milard was responsible for implementing was a change order that solved for the failure to place over 500 lineal feet of DC conductors in code compliance trenches. The solution was to create concrete duct bank that would lie on top of the shallow hardpan and deliver the PVC conduit from the combiner boxes to the inverter pads. This change order required extensive field measurements and coordination with the engineers in LA in order to institutes a properly documented change.

With the Brookfield and Maynard projects, both landfill projects with restrictions from penetrating the landfill cap, Millard was able to incorporate cable trays into the design for these two projects prior to the start of construction. This enabled the designers to freely distribute DC electrical power where ever it was possible to site self ballasted solar support structure on top of the landfill. This also enabled the designers to reduce the size of the electrical conductors due to the fact that they were air cooled in the cable tray according to national electric code. Other benefits to using cable tray are described in the memo below: 

Re:  Coordination of Cable Management with Geotech Report...

as anyone asked the question why we always trench? Here are some downsides to trenching:

Heavy equipment rental costs & dangers, Spoils may contaminate topsoil, Labor to trench is $4.25 - $4.50 / LF, Unforeseens in the ground pose risks, Passing these risks onto contractor is costly., Conduit must be purchased with all attendent fittings, couplings, expansion jts, etc., Resistivity calulations are more heat intensive resulting in more Copper / Aluminum due to heat premium, More length requ’d to transition in / out of ground, More length- more pipe, more labor, more IR loss, More permit risk of env. cost (stockpiling farm soil), Open Trenches restrict movement of site ops, Restrictions of movement cost time / create danger, Erosion issues, Additional OSHA triggers, Landscaping repairs, costs, requirements by AHJ, Difficult to access/ change or repair, Leaks Water/ Damages Cable, The following memo is an illustration of how a project in New England- a place with shallow rocky soil can surprise the veteran PV designer with setbacks that exponentially revise up costs and duration. The Pilgrims and the origins of the Thanksgiving Holiday are truths to be told, Future landfill projects here in New England will dictate that all wire management occur above grade. There will be no trenching on these projects allowed per SEPA. Now is the time to explore options to “trenched earth”, Crystalized: if the Geotech report says there is no soil for a 24” deep trench, find another method of distributing wires around your solar project.

    Challenge Statement: Designers under extreme pressure to print construction issues sometimes make mistakes. These mistakes have to be rectified on site by project managers and construction managers without the benefit of quick decision making processes available to designers- rather than rectifying some vector graphics and text blocks on a cad drawing, PMs & CMs have their sub-contracted partners on the project uncovering unconstructible designs and submitting RFIs, and Change Orders after careful study of the problem. The the Martifer CM / PM team have to convince Design Staff that there is a constructibility problem with the drawing. Depending on the disposition of the designer, the process of realizing the problem can take a while to acceptance.

    Once the designer has accepted the constructiblility challenges of the original construction plan or detail, there is the solution phase. This phase may not take place quickly or, worse, there may be a delay to the solution for all kinds of  other reasons related to change process within Martifer or related to the reluctance to initiate change by other parties in the internal change process. Many times the designer who has accepted the original “mistake” may find acknowledging the original “mistake” as an occuptional hazard and delay or distract the processing of the change.

    This memo looks at a specific technical issue related to underground surprises. The observations made on site have concluded that the original design was not constructible, and there are photographs that show a soil dept that makes it clear- a code compliant conduit trench was indeed not possible to be constructed at this site without the use of dynamite. Pick axes, sledge hammers and pneumatic hammers would not prevail in the conditions at this site in order to deliver the original detail that was drawn on a piece of paper. Some have suggested that the electrical contractor should have detected these conditions in the Geotechnical Report. The good news is that the mounting hardware designer must have, as clearly evidenced by the large, precast concrete ballast blocks:

    While using this “Braille” approach to discovering the extent of the shallow soil, constuction continued at breakneck pace on all aspects of the design, including the inverter pads- The PM & CM were communicating their findings to Martifer and seeking guidance on the solution to this problem of how to cover the conduits for DC distribution on the east side of the site with a code compliant amount of cover... 

    The electrical contractor immediately recommended cable tray to the PM. This suggestion was rejected by Martifer and another solution was proposed- concrete duct bank. This would be cast over the pvc conduits and covered with clear fill. The PM was instructed to obtain a bid for the placement of at least 4” of cast-in-place concrete over the top of the concduit. But how much shallow conduit would be manually determined to require this solution to accurately describe the scope and quantity of the concrete? The trencher had to keep trenching and inspections for shallow trench conditions would have to be made before a drawing that showed the extent of the shallow conditions could be issued to the concrete contractor. This process took a great deal of time.

    As construction continued, new shallow soil challenges emerged such as how to transition from conduit in the proposed concrete duct bank into the inverter since the inverter pads also sat on shallow soil conditions. The drawings had called for bottom entry of the conduits into the DC recombiner and the AC compartments in the inverter. Unfortunately, the concrete ductbank solution for the conduits assumed that the conduits would eventually find their way to deeper soil and consequently to the inverter pad, where they would dive under the pad and emerge through the bottom entry in the inverter. This was not to be the case...another constructibility issue requiring a change order.

Pad details show bottom entry to inverter from trench...

Now that the conduits are to be encased in concrete on the surface of the hardpan, and the inverter pad also sits on the surface of the hardpan, there is no way for the conduits to transition up, into the inverter recombiner through the inverter pad for two reasons;

They are at the same level as the bottom of the slab.

Unless the slab is built up with hundreds of yards of concrete in order to allow sufficient height for the 90 degree transitions to occur under the slab, the conductors have no way to get into the DC compartment nor is there room for the AC conductors to egress the AC compartment to leave the pad and reach the adjoining MV Transformer with a similar bottom entry:

    How to stub up in shallow soil condition?

    Now the PM / CM team on site see the limitations of the concrete encased conduits as far as: how to enter the inverter? Side entry seems likely, but how to transition out of the duct bank to enter the side of the inverter? If they had adopted the cable tray solution presented by the electrical contractor, they would have avoided a great deal of shallow trenching, wire pulling and now concrete encasing. Had tray been adopted, there would still have been concrete duct bank required for maintenance vehicular circulation over the wire runs.

Cable Tray is the more flexible solution for utility scale:

Transition from tray into conduit for vehicle over passes...

Cable Tray is used in many projects where its flexiblility, cost, ease of access to conductors, labor friendliness and tendency to allow other more flexible solutions to other challenges such as combiner box locations, wire transitions from mounting hardware into combiner boxes and inverters with side entry opportunities.

Cable Tray side entry capability for inverter service...

On utility scale projects where agricultural land is environmentally protected, local zoning committees are reluctant to permit multi-MW projects because of the damage that extensive trenching causes to the top soil. In some cases they have required topsoil to be scraped off the surface of the ground to a depth of 12 “ and stockpiled, only later to be re-distributed by the civil contractor after the trenching has completed the process of backfilling the spoils into the trenches. Needless to say this is an expensive additional cost of trenching:

Environmentally protected farmland is often topsoil focused and costly topsoil management is triggered by trenching when this could be avoided by using cable tray.

Use of cable tray eliminates 95% of trenching, conduit, and equipment required to excavate trenches. In fact, at nearly $5 per foot, these eliminations from the construction budget must be subtracted from the cost of tray which typically amounts to $5 to $10 per linear foot. The cost of pulling wire may be equated to the cost of laying wire in tray, but in fact, pulling wire is much more labor intensive than tray layout. There are other savings to be had with cable tray- and that is the savings in copper that there is to recover when applying the open air thermal resistivity coefficient to PV wire sizing- both for home uns to boxes and for larger conductors returning to DC recombiners. Tray provides a valuable route to which small control power conductors in conduit can be clipped onto the side of tray in order to separately deliver AC power to devices on the inverter pad, tracker motors or security devices.

NEMA 3R HOFFMAN BOXES W 12 CIRCUITS EA MOUNTED ON THEIR BACKS ON TRAY AND INSPECTED ALL DAY LONG...

    There is of course, the opportunity to mount combiner boxes on tray and that savings over free standing vertically mounted boxes is  equal to the full value of all concrete, excavation, and strut assemblies which amount to several hundred dollars per box. (not to mention the loss of conduit, elbows, couplings and labor associated with stubbing up.

Side Entry Service for Inverters is accessible and saves a lot of subslab coordination, setting out, and mess on site...

The back mounting of combiner boxes on tray is an electrician’s idea. The transitions from tray to box requires only a minute devation of angle for a Sealitite segment to steer conductors right through the side of the box, into the fuse holders, terminal blocks and grounding lugs. Grounding is easy with tray since the tray itself is used as a grounding conductor provided that jumpers are installed at each tray splice.

   TYPICAL TRANSITION FROM MOUNT TO TRAY...NO PIPE

The proximity of back mounted boxes to their respective source circuits, by nature, minimizes wirelength, improves efficiency of the system design and costs less for copper. The access to the box is from the top and allows for direct skylight to illuminuate the interior of the box. With the door sealed properly with a neopreme weather strip, NEMA 3R boxes are permissible where a NEMA 4 box might otherwise be called for.

ELECTRICIANS ROUTINELY INSTALL BOXES ON THEIR BACKS

The Cable Tray acts as a bi-directional super highway for DC conductors to travel from source circuits to combiner boxes and from combiner boxes to inverter DC recombiners. Tray also is usefull for projects where there is a non-whole number of strings in a row of modules and a jumper is neccessary to complete a string. That jumper can ride on tray (and be shorter, easier to wire and visible) to and from one row to the other row without having to go underground.

    ELECTRICIANS PREFER THE STRAIGHT ENTRY INTO BOX.

Using smaller boxes is a benefit when mounting to tray not only because the tray width is limited (in this case to 12”) but also because circuits travel shorter distances to smaller boxes. True, above ground distribution is an inconvenience for the lawn mower, but the improved site circulation, lack of mud, lack of fall hazards, reduced number of heavy equipment vehicles and other  effects of“trenched earth” are conspicuously absent on a site where cable tray is the rule for wire management, not the exception to the rule.

THIS CABLE TRAY WILL CARY 250KW WORTH OF DC CIRCUITS

    Electricians space conductors in tray in order to benefit from the open air temperature coefficient that reduces the amount of copper required to acheive the same circuit resistance calculation as a conductor in a conduit in a trench buried under utility sand, warning tape, clear fill, top soil and landscaping because of the heat that the conductor emits inside the conduit. Savings on copper alone can amount to $1,000 to $5,000 per MW DC. In this case, the electricians are segregating the inverter home runs to the one side of the tray so that they can freely fill the other side of the tray with the smaller sub-array wiring (which is not by code required to be spaced apart). They may install a separator to insure that the smaller conductors to not creep over onto the the larger conductors which require complete expsure to fresh air according to NEC.Cable Tray can span up to 20’ and remain cost effective for solar projects. The project above has the tray (pictured) spanning 13’ from one mounting hardware  column to another. The tray is supported by a bracket that can be procured from any number of vendors. The bracket detail shown on the detail below is suitbale for a schedule 80 steel pipe that supports a torque tube slew ring. In this case availability of a vertical support for the cable tray is provided by the mounting hardware.

DETAIL SHOWING SEPARATE TRAYS FOR SUB-ARRAY WIRING AND INVERTER HOME RUNS, RUNG SPACING DIFFERS PER TRAY.

Depending on the application, whether by tracker, fixed tilt, carport, roof mount or pole mount- cable tray opportunities to gain free support off of mounting structure often seem to be available for scrutiny, resolution and execution. The best support for a cable tray is often the ballast block that comes with the mounting solution and often it is the driven pier that has been cleared by the structural engineer to act as a dual purpose solution.

CABLE TRAY ON THE ROOF OF AN ELEMENTARY SCHOOL...

The ability of tray to collect conductors from under solar panels is perhaps overlooked as so often we see projects pulling hundreds of feet of cable through conduit and loading those conduit runs on pipe piers and requiring the additional labor to install thermal expansion joints, couplings, elbows and other fittings just to deliver a few pairs of #10 wire to a combiner box. Cable tray is a reliable, durable alternative to conduit and a superior cable management system compared to “trenched earth”.

Project Data

End User: Capitol Lighting Eatontown

Installer: Forest Electric Corp

Location: Eatontown, NJ

Date of Install: May 2006 – July 2006

Size of System in kW: 240

Project Developer: American Energy Technology

Special Challenges Met: Very aggressive schedule

Complete Project Team:                        Electrical Engineer: Engineered Design Group

Architect: Todd Koenig                           Structural Engineer: Thor

Project Brief:

Capitol Lighting is a retail specialty lighting showroom. Capitol Lighting consumes a large amount of energy when displaying lights to customers. TurtleEnergy designed a Photovoltaic system to be installed at Capitol Lighting by Forest Electric (Union Contractor.

Analysis:

TurtleEnergy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers (Stellar Energy Solutions)

The project commenced in May of 2006 and was successfully completed in July of 2006.

Project Data

End-User: Capitol Lighting E. Hanover

Installer: Forest Electric and IBEW

Location: East Hanover, NJ

Date of install: March 2004 – May 2004

Size of system in kW: 100kW

Energy produced since installation

Special Challenges Met: 1) roof structure    2) installation during winter

Project Brief

Capitol Lighting is a retail specialty lighting showroom. Capitol Lighting consumes a large amount of energy when displaying lights to customers. TurtleEnergy designed a Photovoltaic system to be installed at Capitol Lighting by Forest Electric (Union Contractor) who teamed with IBEW (local 102).

TurtleEnergy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers (Stellar Energy Solutions)

This renewable energy project was implemented during the winter season.  The building had a roof that presented a unique set of requirements and challenges for the installation of a Photovoltaic system. TurtleEnergy engaged Harrison Hamnett, PC to verify compatibility of the roofing structure with the proposed Photovoltaic system. A roofer was contracted to install the PV mounting system and Stellar Energy Solutions provided construction management as well as sales management to Capitol Lighting.

The project commenced in March of 2004 and was successfully completed in May of 2004. The Capitol Lighting East Hanover project implemented one of the first uses of a Satcon Inverter in NJ. The size of the PV system for Capitol Lighting East Handover is 117kW.

The first use of Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented at Capitol Lighting East Hanover. The Fat Spaniel data acquisition illustrations show snapshots of the actual energy generation by the PV system for Capitol Lighting. These measurements are in compliance with the predicted analysis done by TurtleEnergy and in some cases slightly exceed the target energy output range. Data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. The installed PV system has successfully helped reduce the on-grid energy usage and lower cost for Capitol Lighting.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 100kw Inverter

Sapc 165w Module

Schott Solar FS Mounting System

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

Project Data

End User: Capitol Lighting Paramus

Installer: Forest Electric Corp

Location: Paramus, NJ

Date of Install: Sept 2006 – Nov 2006

Size of System in kW: 140

Project Developer: American Energy Technology

Special Challenges Met: Very aggressive schedule.

Complete Project Team:                        Electrical Engineer: Engineered Design Group

Architect: Todd Koenig                           Structural Engineer: Thor

Project Brief:

Capitol Lighting is a retail specialty lighting showroom. Capitol Lighting consumes a large amount of energy when displaying lights to customers. TurtleEnergy designed a Photovoltaic system to be installed at Capitol Lighting by Forest Electric (Union Contractor.

Analysis:

TurtleEnergy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers (Stellar Energy Solutions)

The project commenced in and was successfully completed 

Project Data:

End-User: Washington Gas

Installer: Martifer Solar USA

Location: Southbridge, Ma.

Date of install: April 2013

Size of system in kW: 3400kW

Energy produced since installation: approximately 9,800MWh as of 2/2015

Special Challenges Met: Shallow soil conditions were not anticipated by the EPC design team

Project Brief:

John Millard was hired by Martifer Solar in November of 2012 to manage four utility scale solar projects in New England, the Maynard Landfill Solar project was one of these projects. 

Millard hired the the four project teams that would execute the four designs produced by Martifer Solar USA project engineers in LA. Millard oversaw the design of each project and managed the production of construction documents for each design except for the Southbridge project which had already been designed by the time of his joining Martifer in November 2012. Of the four solar projects, three of the projects were located on landfill sites. The Maynard Massachusetts project and the Brookfield Massachusetts project both required designs that would not penetrate the landfill. This required that all electricity distribution for the solar project would utilize code compliant cable tray design and self ballasted mounting hardware for the solar support structure. s was discovered at the Southbridge Massachusetts project, New England soils are typically shallow and represent hard dig conditions. Application engineers ignore this fact of life at their peril.

In the case of the Southbridge Massachusetts project, soil depth issues were already preventing extensive trenching to code-compliant depth across the 3.4 MW Solar project construction site. One of the first corrective actions that Milard was responsible for implementing was a change order that solved for the failure to place over 500 lineal feet of DC conductors in code compliance trenches. The solution was to create concrete duct bank that would lie on top of the shallow hardpan and deliver the PVC conduit from the combiner boxes to the inverter pads. This change order required extensive field measurements and coordination with the engineers in LA in order to institutes a properly documented change.

With the Brookfield and Maynard projects, both landfill projects with restrictions from penetrating the landfill cap, Millard was able to incorporate cable trays into the design for these two projects prior to the start of construction. This enabled the designers to freely distribute DC electrical power where ever it was possible to site self ballasted solar support structure on top of the landfill. This also enabled the designers to reduce the size of the electrical conductors due to the fact that they were air cooled in the cable tray according to national electric code. Other benefits to using cable tray are described in the memo below: 

Re:  Coordination of Cable Management with Geotech Report...

A learning opportunity is evolving here on the East Coast that will serve us well. Without being too project specific, the challenges experienced here will touch every department in the company.

    As a newcomer to Martifer, and aware of the “hindsight is 20 / 20” rule, making observations about decisions taken by presdescessors is a luxury. Now that I am one of the decisionmakers on these projects, vulnearble to making decisions on the fly that appear to make me look like a good “multi-tasker” when in reality, I may be making a hasty decision that costs- and costs dearly.

    Therefore, a quality control process known as a “peer review” is an opportunity for a second set of eyes to scan the drawings for design decisions that may have been made hastily (prior to contract award). Decisions such as carte blanche trenching to distribute DC wiring: many ground mounted projects will sustain hundreds of metres of trenching for this purpose. Has anyone asked the question why we always trench? Here are some downsides to trenching:

Heavy equipment rental costs & dangers, Spoils may contaminate topsoil, Labor to trench is $4.25 - $4.50 / LF, Unforeseens in the ground pose risks, Passing these risks onto contractor is costly., Conduit must be purchased with all attendent fittings, couplings, expansion jts, etc., Resistivity calulations are more heat intensive resulting in more Copper / Aluminum due to heat premium, More length requ’d to transition in / out of ground, More length- more pipe, more labor, more IR loss, More permit risk of env. cost (stockpiling farm soil), Open Trenches restrict movement of site ops, Restrictions of movement cost time / create danger, Erosion issues, Additional OSHA triggers, Landscaping repairs, costs, requirements by AHJ, Difficult to access/ change or repair, Leaks Water/ Damages Cable, The following memo is an illustration of how a project in New England- a place with shallow rocky soil can surprise the veteran PV designer with setbacks that exponentially revise up costs and duration. The Pilgrims and the origins of the Thanksgiving Holiday are truths to be told, Future landfill projects here in New England will dictate that all wire management occur above grade. There will be no trenching on these projects allowed per SEPA. Now is the time to explore options to “trenched earth”, Crystalized: if the Geotech report says there is no soil for a 24” deep trench, find another method of distributing wires around your solar project.

    Challenge Statement: Designers under extreme pressure to print construction issues sometimes make mistakes. These mistakes have to be rectified on site by project managers and construction managers without the benefit of quick decision making processes available to designers- rather than rectifying some vector graphics and text blocks on a cad drawing, PMs & CMs have their sub-contracted partners on the project uncovering unconstructible designs and submitting RFIs, and Change Orders after careful study of the problem. The the Martifer CM / PM team have to convince Design Staff that there is a constructibility problem with the drawing. Depending on the disposition of the designer, the process of realizing the problem can take a while to acceptance.

    Once the designer has accepted the constructiblility challenges of the original construction plan or detail, there is the solution phase. This phase may not take place quickly or, worse, there may be a delay to the solution for all kinds of  other reasons related to change process within Martifer or related to the reluctance to initiate change by other parties in the internal change process. Many times the designer who has accepted the original “mistake” may find acknowledging the original “mistake” as an occuptional hazard and delay or distract the processing of the change.

    This memo looks at a specific technical issue related to underground surprises. The observations made on site have concluded that the original design was not constructible, and there are photographs that show a soil dept that makes it clear- a code compliant conduit trench was indeed not possible to be constructed at this site without the use of dynamite. Pick axes, sledge hammers and pneumatic hammers would not prevail in the conditions at this site in order to deliver the original detail that was drawn on a piece of paper. Some have suggested that the electrical contractor should have detected these conditions in the Geotechnical Report. The good news is that the mounting hardware designer must have, as clearly evidenced by the large, precast concrete ballast blocks:

    While using this “Braille” approach to discovering the extent of the shallow soil, constuction continued at breakneck pace on all aspects of the design, including the inverter pads- The PM & CM were communicating their findings to Martifer and seeking guidance on the solution to this problem of how to cover the conduits for DC distribution on the east side of the site with a code compliant amount of cover... 

    The electrical contractor immediately recommended cable tray to the PM. This suggestion was rejected by Martifer and another solution was proposed- concrete duct bank. This would be cast over the pvc conduits and covered with clear fill. The PM was instructed to obtain a bid for the placement of at least 4” of cast-in-place concrete over the top of the concduit. But how much shallow conduit would be manually determined to require this solution to accurately describe the scope and quantity of the concrete? The trencher had to keep trenching and inspections for shallow trench conditions would have to be made before a drawing that showed the extent of the shallow conditions could be issued to the concrete contractor. This process took a great deal of time.

    As construction continued, new shallow soil challenges emerged such as how to transition from conduit in the proposed concrete duct bank into the inverter since the inverter pads also sat on shallow soil conditions. The drawings had called for bottom entry of the conduits into the DC recombiner and the AC compartments in the inverter. Unfortunately, the concrete ductbank solution for the conduits assumed that the conduits would eventually find their way to deeper soil and consequently to the inverter pad, where they would dive under the pad and emerge through the bottom entry in the inverter. This was not to be the case...another constructibility issue requiring a change order.

Pad details show bottom entry to inverter from trench...

Now that the conduits are to be encased in concrete on the surface of the hardpan, and the inverter pad also sits on the surface of the hardpan, there is no way for the conduits to transition up, into the inverter recombiner through the inverter pad for two reasons;

They are at the same level as the bottom of the slab.

Unless the slab is built up with hundreds of yards of concrete in order to allow sufficient height for the 90 degree transitions to occur under the slab, the conductors have no way to get into the DC compartment nor is there room for the AC conductors to egress the AC compartment to leave the pad and reach the adjoining MV Transformer with a similar bottom entry:

    How to stub up in shallow soil condition?

    Now the PM / CM team on site see the limitations of the concrete encased conduits as far as: how to enter the inverter? Side entry seems likely, but how to transition out of the duct bank to enter the side of the inverter? If they had adopted the cable tray solution presented by the electrical contractor, they would have avoided a great deal of shallow trenching, wire pulling and now concrete encasing. Had tray been adopted, there would still have been concrete duct bank required for maintenance vehicular circulation over the wire runs.

Cable Tray is the more flexible solution for utility scale:

Transition from tray into conduit for vehicle over passes...

Cable Tray is used in many projects where its flexiblility, cost, ease of access to conductors, labor friendliness and tendency to allow other more flexible solutions to other challenges such as combiner box locations, wire transitions from mounting hardware into combiner boxes and inverters with side entry opportunities.

Cable Tray side entry capability for inverter service...

On utility scale projects where agricultural land is environmentally protected, local zoning committees are reluctant to permit multi-MW projects because of the damage that extensive trenching causes to the top soil. In some cases they have required topsoil to be scraped off the surface of the ground to a depth of 12 “ and stockpiled, only later to be re-distributed by the civil contractor after the trenching has completed the process of backfilling the spoils into the trenches. Needless to say this is an expensive additional cost of trenching:

Environmentally protected farmland is often topsoil focused and costly topsoil management is triggered by trenching when this could be avoided by using cable tray.

Use of cable tray eliminates 95% of trenching, conduit, and equipment required to excavate trenches. In fact, at nearly $5 per foot, these eliminations from the construction budget must be subtracted from the cost of tray which typically amounts to $5 to $10 per linear foot. The cost of pulling wire may be equated to the cost of laying wire in tray, but in fact, pulling wire is much more labor intensive than tray layout. There are other savings to be had with cable tray- and that is the savings in copper that there is to recover when applying the open air thermal resistivity coefficient to PV wire sizing- both for home uns to boxes and for larger conductors returning to DC recombiners. Tray provides a valuable route to which small control power conductors in conduit can be clipped onto the side of tray in order to separately deliver AC power to devices on the inverter pad, tracker motors or security devices.

NEMA 3R HOFFMAN BOXES W 12 CIRCUITS EA MOUNTED ON THEIR BACKS ON TRAY AND INSPECTED ALL DAY LONG...

    There is of course, the opportunity to mount combiner boxes on tray and that savings over free standing vertically mounted boxes is  equal to the full value of all concrete, excavation, and strut assemblies which amount to several hundred dollars per box. (not to mention the loss of conduit, elbows, couplings and labor associated with stubbing up.

Side Entry Service for Inverters is accessible and saves a lot of subslab coordination, setting out, and mess on site...

The back mounting of combiner boxes on tray is an electrician’s idea. The transitions from tray to box requires only a minute devation of angle for a Sealitite segment to steer conductors right through the side of the box, into the fuse holders, terminal blocks and grounding lugs. Grounding is easy with tray since the tray itself is used as a grounding conductor provided that jumpers are installed at each tray splice.

   TYPICAL TRANSITION FROM MOUNT TO TRAY...NO PIPE

The proximity of back mounted boxes to their respective source circuits, by nature, minimizes wirelength, improves efficiency of the system design and costs less for copper. The access to the box is from the top and allows for direct skylight to illuminuate the interior of the box. With the door sealed properly with a neopreme weather strip, NEMA 3R boxes are permissible where a NEMA 4 box might otherwise be called for.

ELECTRICIANS ROUTINELY INSTALL BOXES ON THEIR BACKS

The Cable Tray acts as a bi-directional super highway for DC conductors to travel from source circuits to combiner boxes and from combiner boxes to inverter DC recombiners. Tray also is usefull for projects where there is a non-whole number of strings in a row of modules and a jumper is neccessary to complete a string. That jumper can ride on tray (and be shorter, easier to wire and visible) to and from one row to the other row without having to go underground.

    ELECTRICIANS PREFER THE STRAIGHT ENTRY INTO BOX.

Using smaller boxes is a benefit when mounting to tray not only because the tray width is limited (in this case to 12”) but also because circuits travel shorter distances to smaller boxes. True, above ground distribution is an inconvenience for the lawn mower, but the improved site circulation, lack of mud, lack of fall hazards, reduced number of heavy equipment vehicles and other  effects of“trenched earth” are conspicuously absent on a site where cable tray is the rule for wire management, not the exception to the rule.

THIS CABLE TRAY WILL CARY 250KW WORTH OF DC CIRCUITS

    Electricians space conductors in tray in order to benefit from the open air temperature coefficient that reduces the amount of copper required to acheive the same circuit resistance calculation as a conductor in a conduit in a trench buried under utility sand, warning tape, clear fill, top soil and landscaping because of the heat that the conductor emits inside the conduit. Savings on copper alone can amount to $1,000 to $5,000 per MW DC. In this case, the electricians are segregating the inverter home runs to the one side of the tray so that they can freely fill the other side of the tray with the smaller sub-array wiring (which is not by code required to be spaced apart). They may install a separator to insure that the smaller conductors to not creep over onto the the larger conductors which require complete expsure to fresh air according to NEC.Cable Tray can span up to 20’ and remain cost effective for solar projects. The project above has the tray (pictured) spanning 13’ from one mounting hardware  column to another. The tray is supported by a bracket that can be procured from any number of vendors. The bracket detail shown on the detail below is suitbale for a schedule 80 steel pipe that supports a torque tube slew ring. In this case availability of a vertical support for the cable tray is provided by the mounting hardware.

DETAIL SHOWING SEPARATE TRAYS FOR SUB-ARRAY WIRING AND INVERTER HOME RUNS, RUNG SPACING DIFFERS PER TRAY.

Depending on the application, whether by tracker, fixed tilt, carport, roof mount or pole mount- cable tray opportunities to gain free support off of mounting structure often seem to be available for scrutiny, resolution and execution. The best support for a cable tray is often the ballast block that comes with the mounting solution and often it is the driven pier that has been cleared by the structural engineer to act as a dual purpose solution.

CABLE TRAY ON THE ROOF OF AN ELEMENTARY SCHOOL...

The ability of tray to collect conductors from under solar panels is perhaps overlooked as so often we see projects pulling hundreds of feet of cable through conduit and loading those conduit runs on pipe piers and requiring the additional labor to install thermal expansion joints, couplings, elbows and other fittings just to deliver a few pairs of #10 wire to a combiner box. Cable tray is a reliable, durable alternative to conduit and a superior cable management system compared to “trenched earth”.

Project Data

End-User: Private Resident

Installer: Hoff Systems

Location: Hoboken, NJ

Date of install: April 2005

Size of system in kW: 5.1KW

Energy produced since installation: 50MWh

Special Challenges Met: Roofscape

Project Brief:

Project Data

End-User: Lincoln School

Installer: Evco Mechanical and IBEW

Location: Kearny, NJ

Date of install: Sept. 2005

Size of system in kW: 150kW

Energy produced since installation

Special Challenges Met: 1) roof addition;   2) roof-top mechanical upgrade;  3) roof-mounted HVAC system; 204v to 408v upgrade

Project Brief

TurtleEnergy successfully won the bid to design and support a Photovoltaic (PV) system for the Kearny Board of Education (BOE) in September of 2004. Evco Mechanical successfully won the public bid to install the TurtleEnergy PV system on four Kearny schools. The Lincoln School was the first of 4 schools to be installed by Evco Mechanical. The project commence in September of 2005.

The design of the Lincoln School PV system was a challenge because the BOE had decided to implement a plan to build an addition to the school and update the rooftop mechanical systems in the school. The engineers designing the future rooftop mechanical system provided TurtleEnergy with the plans for the new HVAC system on the roof.

A detailed analysis of the site was done by TurtleEnergy. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers

TurtleEnergy designed the PV system to coexist with the future roof-mounted HVAC system. In addition, the electrical engineer had plans to upgrade the main electrical voltage to the building from 208 volts to 480 volts in two years time. TurtleEnergy designed the PV system to accommodate the future change of voltage. Evco Mechanical together with the International Brotherhood of Electrical Workers (IBEW) (local 164) installed the PV system in 60 days. The size of the PV system for the Lincoln School is 150kw.

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented for the Service Tire project. The Fat Spaniel data acquisition system, logs the actual energy generation by the PV system. The resulting measurements are in compliance with the predicted analysis done by TurtleEnergy. The Fat Spaniel system data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals.

Schott Solar provided TurtleEnergy with valuable design support and supply of PV modules and mounting hardware for the project. The New Jersey Clean Energy Program and the school’s construction corporation provided full funding for the project.

For additional information on product specifications see the cut sheets listed below.

Satcon 135kw Inverter

Sapc ASE 300 Module

B-Line Cable Tray

Schott Solar FS Mounting System

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: Garfield School

Installer: Evco Mechanical

Location: Kearny, NJ

Date of install: Nov. 2005

Size of system in kW: 54kW

Energy produced since installation

Special Challenges Met: 1) inclement weather, 2) 100 year structure with timber-frame roof

Project Brief

TurtleEnergy successfully won the bid to design and support a Photovoltaic (PV) system for the Kearny Board of Education (BOE) in September of 2004. Evco Mechanical successfully won the public bid to install the TurtleEnergy PV system on four Kearny schools. The Garfield school was the third of 4 schools to be installed by Evco Mechanical. The project commenced in January of 2006. Due to much snow and inclement weather it was completed in April of 2006.

The Garfield School is a 100 year old structure with a timber-frame roof. A detailed analysis of the site was done by TurtleEnergy. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers

TurtleEnergy together with Schott Solar provided detailed loading criteria data to Civil Engineer Pany & Letts who carried out a wind analysis to certify that the penetration-less mounting system would perform well in high winds. Structural engineer Robert Silman Associates certified that the weight of the PV system was compatible with the 100 year old existing structure. The size of the PV system for the Garfield School is 54kW.

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented for the Service Tire project. The Fat Spaniel data acquisition system, logs the actual energy generation by the PV system. The resulting measurements are in compliance with the predicted analysis done by TurtleEnergy. The Fat Spaniel system data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals.

Schott Solar provided TurtleEnergy with valuable design support and supply of PV modules and mounting hardware for the project. The New Jersey Clean Energy Program and the school’s construction corporation provided full funding for the project.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 100kw Inverter

SMA inverter

Schott Solar ASE 300 – 270W PV Module

B-Line Cable Tray

Schott Solar FS Mounting System

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: Schuyler School

Installer: Evco Mechanical and IBEW

Location: Kearny, NJ

Date of install:

Size of system in kW: 135kW

Energy produced since installation

Special Challenges Met: 1) two resident voltages;  2) two separate buildings  3) re-roofing project

Project Brief

TurtleEnergy successfully won the bid to design and support a Photovoltaic (PV) system for the Kearny Board of Education (BOE) in September of 2004. Evco Mechanical successfully won the public bid to install the TurtleEnergy PV system on four Kearny schools. The Schuyler school was the second of 4 schools to be installed by Evco Mechanical. The project commenced in November of 2005. A detailed analysis of the site was done by TurtleEnergy. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers

The Schuyler School was a challenge for TurtleEnergy because the building has two resident voltages (208 volts and 480 volts). The school also consisted of two separate buildings upon which two different PV systems were planned. The total size of the planned PV system was 135kw. Due to the large travel distance between the 2 buildings, a multi-PV system design approach was utilized using a combination of SMA converters and one SATCON 100 kw Inverter. The Kearny BOE implemented a re-roofing project and TurtleEnergy coordinated the design of the PV system with the warranty provided by the roofer so that the roofer would be comfortable with the installation on his warrantee roof. The architect of the re-roofing project provided a valuable roof plan which described the future roofscape. TurtleEnergy worked closely with the architect to coordinate the roof plan with the design of the PV system. The size of the PV system for the Schuyler School is 135kW. Evco Mechanical completed the installation after closely participating in the design process. Evco Mechanical completed the installation in the middle of the winter in 90 days.

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented for the Schuyler project. The Fat Spaniel data acquisition system, logs the actual energy generation by the PV system. The resulting measurements are in compliance with the predicted analysis done by TurtleEnergy. The Fat Spaniel system data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals.

Schott Solar provided TurtleEnergy with valuable design support and supply of PV modules and mounting hardware for the project. The New Jersey Clean Energy Program and the school’s construction corporation provided full funding for the project.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 100kw Inverter

SMA inverter

Schott Solar Module (ASE 300 – 315W)

B-Line Cable Tray

Schott Solar FS Mounting System

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: Washington School

Installer: Evco Mechanical

Location: Kearny, NJ

Date of install: Feb. 2006 – May 2006

Size of system in kW: 139kW

Energy produced since installation

Special Challenges Met: 1) 100 year structure with iron and concrete frame roof

Project Brief

TurtleEnergy successfully won the bid to design and support a Photovoltaic (PV) system for the Kearny Board of Education (BOE) in September of 2004. Evco Mechanical successfully won the public bid to install the TurtleEnergy PV system on four Kearny schools. The Washington School was the first of 4 schools to be installed by Evco Mechanical. The project commenced in February of 2006 and was completed in May of 2006.

The Washington School is a 3-story elementary school in Kearny, NJ. It is a 100 year old structure with an iron and concrete-frame roof. A detailed analysis of the site was done by TurtleEnergy. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers

TurtleEnergy together with Schott Solar provided detailed loading criteria data to Civil Engineer Pany & Letts who carried out a wind analysis to certify that the penetration-less mounting system would perform well in high winds. Structural engineer, Robert Silman Associates, certified that the weight of the PV system was compatible with the 100 year old existing structure.

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented for the Service Tire project. The Fat Spaniel data acquisition system, logs the actual energy generation by the PV system. The resulting measurements are in compliance with the predicted analysis done by TurtleEnergy. The Fat Spaniel system data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. The size of the PV system for the Washington School is 139kW.

Schott Solar provided TurtleEnergy with valuable design support and supply of PV modules and mounting hardware for the project. The New Jersey Clean Energy Program and the school’s construction corporation provided full funding for the project.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 135kw Inverter

Schott Solar ASE 300 – 330W Multi-Crystalline PV Module

B-Line Cable Tray

Schott Solar FS Mounting System

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: NJ Public Health Environmental Agricultural Laboratory

Installer: Hatzel Buehler, Inc.

Location: Trenton, New Jersey

Date of install: October 2006

Size of system in kW: 175kW

Energy produced since installation: 1,800 MWh

Special Challenges Met: Construction Schedule

Architect: HOK

Project Brief

Table of Contents:

1. Introduction

2. Technical Design Approach

    2.1 System Performance

    2.2 Array Mounting Structure

    2.3 PV Modules

    2.4 Inverters

    2.5 Balance of System

    2.6 Monitoring System

The following submittal allows for the installation of QTY(1000) 175W MonoCrystalline SolarWorld Modules on the roof of the New Jersey Public Health, Environmental and Agricultural Laboratory at a tilt angle of 5 degrees using SunLink mounting hardware. It is important to confirm that the roof structure of the NJPHEAL is capable of supporting a distributed load of up to 7lbs./sf additional to the code compliant snow load. It is in this safety margin of structural performance that a self ballasted mounting system which tilts the modules at 5 degrees can be mounted without penetrations to the roof. Based on a 100 MPH 3 second gust, and exposure class B the preliminary dead loads of the non-penetrating PV systems for the 88’ high upper roof, the 64’ high lower roof and 31’ high Pavillion roof are 6.7 PSF, 6.1 PSF, and 5.0 PSF respectively.

Electrically, this submittal departs from the construction documents in the following ways:

Where the construction documents call for two separate inverters for the upper roof with 0 degree sloping modules and the lower roof with 13 degree sloping modules, we have proposed one Satcon 135kW Inverter for both roofs which are both proposed at 5 degrees- upper roof, (63kW SW175s) and lower roofs (79.8kW SW175s).

Where the construction documents call for separate inverters for the pavillion array, we have proposed one Satcon 30kW Inverter for the proposed 32.2kW array mounted at 5 degrees on SunLink.

While our 1-Line diagrams show separate AC disconnects for the 30kW and the 135kW inverters, the construction documents show a pv system master ac disconnect. This solution may be adopted if preferred over separate ac disconnects. We note the use of the inverters’ integrated switches in the construction documents.

The monitoring system is not shown on our 1-Line diagram and we propose to conform to the construction docs.

3.1. System Performance

PV system performance is influenced by a wide variety of factors including system installation practices, wire sizing, weather conditions, inverter loading, orientation towards south, available sunlight, etc. As such, we can predict system performance with a high level of accuracy. However the model used does include these factors. The charts below show expected AC output from the proposed system given the following de-rate assumptions:

Hourly weather data from the National Renewable Energy Laboratory’s 239-station TMY2 database and a PV performance model based on a Sandia National Laboratories’ Algorithm. (technical references are available upon request.) are used to estimate monthly and annual AC energy production (kWh) for a crystalline silicon PV system. 

Notes on performance estimates. The analysis of system performance assume the following:

1. Insolation data is based on averages – actual insolation will vary.

2. Thermal and electrical coefficients for the modules as provided by the manufacturer.

3. There is no significant shading of the system.

4. Actual energy production will vary according to insolation, temperature, shading, age of the array and many other factors.

5. These figures are for estimation purposes only and are not a guarantee. Comparisons between systems should be made based on AC rating, orientation, array operating temperature and tilt of the system as opposed to predicted output.

3.2. Array Mounting Structure – Sunlink

TurtleEnergy will mount the PV array on the roof using Sunlink mounting assemblies. This creates an interlocking structure that requires ballasting and no roof penetrations. Our experience with flat roof PV systems suggests avoiding laying PV modules flat or directly on top of the roof for the following reasons:

· Higher Energy Capture – Simply by facing the sun more directly, a tilted array captures more energy. Even a 5-degree tilt generates up to 4% more energy than a flat array.

· Cooler Operating Temperature – A tilted array allows natural convection to cool the array, allowing modules to operate more efficiently and increases the equipment life. Flat arrays with less air circulation operate at higher temperatures and produce less power – just when it is needed for peak building loads.

· Improved Roof Drainage – An elevated structure also allows for better roof drainage. Water and air can circulate freely over the roof surface, just as intended by roofing manufacturers.

· Easy Roof Access – This mounting approach allows easy access to roof surface for maintenance or repairs of the surface or the array. For minor repairs, panel assemblies can be left in place or tilted up out of the way.

We are proposing that all PV modules be tilted at 20° and that the mounting structure be elevated above the roof surface to allow for roof access and air circulation. All mounting structures we supply and install utilize heavy duty,

long lasting materials. PV modules are supplied with factory-fabricated frames (for longer life, and greater module strength). These frames are mechanically attached to the aluminum support structure using stainless steel fasteners.

For this project, the Solar World 175W modules will be panelized in groups of 3 & 4. We have grouped the modules to allow for access to the roof and other equipment. The system is designed to add less than 10 pounds per square foot of roof loading.

Your building is a valuable asset. SunLink helps keep it that way with the most roof-friendly PV mounting system in the industry.

non-penetrating

Together with your engineers and permitting authorities, SunLink® designs the best method to secure the array to your building. Most situations can be successfully addressed without roof penetrations. But in those cases where they are required, the SunLink system needs only a fraction of those needed by competing brands.

quick and easy roof access

Only SunLink offers Tilt-Access™, a unique feature that lets you flip the panels up and out of the way so you can inspect the roof and perform routine maintenance without taking apart the system.

high quality, long lasting materials

Light but strong all aluminum and stainless-steel construction means the SunLink system is rugged, durable, corrosion-free, and elegant. Your building is a valuable asset. SunLink helps you keep it that way.

modules are more efficient

PV modules produce less power when they get hot. The SunLink design promotes air circulation keeping modules cool and efficient.

higher energy output

Only SunLink offers 5°, 10°, 15°, and 20° tilt angles. A steeper angle receives more sunlight which translates to more annual energy production, lower electric bills and, in many cases, no electric bills.

The following submittal allows for the installation of QTY(1000) 175W MonoCrystalline SolarWorld Modules on the roof of the New Jersey Public Health, Environmental and Agricultural Laboratory at a tilt angle of 5 degrees using SunLink mounting hardware. It is important to confirm that the roof structure of the NJPHEAL is capable of supporting a distributed load of up to 7lbs./sf additional to the code compliant snow load. It is in this safety margin of structural performance that a self ballasted mounting system which tilts the modules at 5 degrees can be mounted without penetrations to the roof. Based on a 100 MPH 3 second gust, and exposure class B the preliminary dead loads of the non-penetrating PV systems for the 88’ high upper roof, the 64’ high lower roof and 31’ high Pavillion roof are 6.7 PSF, 6.1 PSF, and 5.0 PSF respectively.

3.2. Array Mounting Structure – Sunlink (Continued)

SunLink® is compatible with all PV modules and needs no roof penetrations. The building owner will love the roof friendly features and you’ll appreciate how product testing and support can smooth the permitting process.

easy to permit

The SunLink system has been successfully permitted on 100’s of projects in virtually every wind, snow and seismic zone across the country. Our system has also undergone the most rigorous wind tunnel testing and computer modeling in the industry. Combine this breadth of experience and this depth of data with our expert engineering and sales support and we have what it takes to help you get your project through the process.

worry free

Non-penetrating mounting means leak-free liability. Rust resistant materials leave no unsightly stains on the roof. And our 15-year warranty assures that SunLink stands behind what it sells.

appealing aesthetics

Clean lines, crisp design and advanced aerodynamics makes the SunLink system one of the most visually appealing PV products available anywhere. We took an under appreciated but vital component and gave it heft, grace and an elegance that complements the architecture of any flat roof building.

brilliantly engineered

This highly engineered system is among the most roof-friendly offerings in the market requiring minimal or no roof penetrations to secure it to the building. Additionally, the unique design virtually eliminates ponding and lightweight but strong aluminum construction is rust-free and corrosion resistant.

wind tunnel tested

Subjecting the SunLink mounting system to the most extensive and sophisticated wind tunnel testing available has placed SunLink among the world’s foremost authorities on the wind’s effects on PV arrays. Component and system modeling, finite element analysis, mechanical load testing, structural frame analysis, electrical bond testing, wire management modeling and materials environmental testing round out the company’s rigorous product development process.

proven in the field

Nearly 200+ SunLink systems have been sold in 17 states and Canada totaling more than 30 Megawatts. From Hawaii to New York, in virtually every wind, weather and seismic zone, SunLink systems are meeting the needs of building owners, building departments and the building trades.

every roof unique

Because no roof is alike and every installation is custom, our engineers work in consultation with roofers, roof manufacturers, building owners, facility managers, architects, engineers, permitting authorities and independent consultants to design the optimized mounting architecture specifically for that site.

experienced expertise

Our sales team excels in helping clients define their needs; our designers produce layouts that optimize module placement at the site and our engineers deliver the data, calculations and the analysis to meet even the most stringent of building codes. Whether you need some questions answered or complete specifications, SunLink can deliver what you require.

Project Data

End-User: NJ Public Health Environmental Agricultural Laboratory

Installer: Hatzel Buehler, Inc.

Location: Trenton, New Jersey

Date of install: October 2006

Size of system in kW: 175kW

Energy produced since installation: 1,800 MWh

Special Challenges Met: Construction Schedule

Architect: HOK

Project Brief:

2.3 Recommended PhotoVoltaic Module:

TurtleEnergy is using the Solar World SW-175 Mono 175 watt Sunmodule for this system. The Sunmodule Plus heralds an innovative new module concept from SolarWorld AG. The fully automated production process at the SolarWorld factories creates a quality of module that is consistently high, which in turn will ensure high yields for the long term. The module frame and the glass it surrounds are firmly attached to each other by silicone that is applied with continuous precision. This guarantees exceptional rigidity for the entire module and stops any possible loosening of the frame as a result of strong outward forces in cases such as sliding of heavy snow. Tests carried out in accordance with IEC 61215, applying loads up to 5.4 kN/m2, confirm that the module can withstand heavy accumulations of snow and ice. The patented, flat and compact junction box provides perfect protection against corrosion, as well as a capacity to rapidly rid itself of any excess heat providing high temperature handling. The junction box is reliably connected by a solid, welded bond to guarantee lasting functionality. In addition, high-quality, robust cables with factory equipped connectors are used. The ability to recycle the modules and a 25-year performance warranty are the finishing touches to this top-quality concept.

As can be seen in the adjoining list of eligible photovoltaic modules, the SolarWorld module has a leading product efficiency. Only the Sanyo 175W HIT module has a higher efficiency in this list of 160W-181W modules. This list has been prepared by the California Energy Commission and can be viewed at: 

http://www.gosolarcalifornia.org/equipment/pvmodule.php

* PTC refers to PVUSA Test Conditions, which were developed to test and compare PV systems as part of the PVUSA (Photovoltaics for Utility Scale Applications) project. PTC are 1,000 Watts per square meter solar irradiance, 20 degrees C air temperature, and wind speed of 1 meter per second at 10 meters above ground level. PV manufacturers use Standard Test Conditions, or STC, to rate their PV products. STC are 1,000 Watts per square meter solar irradiance, 25 degrees C cell temperature, air mass equal to 1.5, and ASTM G173-03 standard spectrum. The PTC rating, which is lower than the STC rating, is generally recognized as a more realistic measure of PV output because the test conditions better reflect “real-world” solar and climatic conditions, compared to the STC rating. All ratings in the list are DC (direct current) watts.

Neither PTC nor STC account for all “real-world” losses. Actual solar systems will produce lower outputs due to soiling, shading, module mismatch, wire losses, inverter and transformer losses, shortfalls in actual nameplate ratings, panel degradation over time, and high-temperature losses for arrays mounted close to or integrated within a roofline. These loss factors can vary by season, geographic location, mounting technique, azimuth, and array tilt. Examples of estimated losses from varying factors can be found at:

http://rredc.nrel.gov/solar/codes_algs/PVWATTS/system.html.

2.5. Balance of System

Module interconnect wires and output cables will be sunlight resistant outdoor rated wiring without conduit. Wiring from the arrays to the inverters will be in sunlight resistant outdoor rated wiring and/or conductors in surface mounted EMT conduit. All DC wiring will use copper conductors sized to minimize IR (voltage) losses to 3% or less of the nominal system voltage. A DC disconnect switch rated for 600V will be provided for each inverter.

PV array combiner boxes are included in the array configuration. Each combiner box includes fuses and surge suppression. The combiner boxes also facilitate the safe operation and troubleshooting of the array by providing easily accessible test points. TurtleEnergy will provide all module interconnect wiring and panel output cables to the combiner boxes; and wire and conduit from the combiner boxes to the disconnect switches; and wiring from the inverter to the point of interconnection at the main switchboard as indicated on the project drawings.

The electrical installation will conform to the applicable portions of the 2002 National Electrical Code. UL listed components will be used where available, and all DC related hardware will be rated for DC applications.

2.6 Monitoring System

Our proposal includes a state-of-the-art monitoring system that will gather and record weather related and system performance parameters as outlined below. In addition, our proposal includes a website driven display of this data along with the appropriate environmental attributes – i.e.: pounds of CO2 or SO2 avoided, equivalent formulas for barrels of oil or tons of coal, etc. We will work with you to develop a website display that meets your objectives. The monitoring system will include a high-quality datalogger and communications equipment for displaying this information on the worldwide web or on-site computer terminal. This system provides a high-visibility means to communicate the system performance. Parameters from the system (as well as other messages) can be displayed.

We will provide a data logging system which will include the following:

Multi Channel Data Logger to monitor the following parameters

Real-time Power, Sunlight, Wind Speed, Air Temperature and

Instantaneous system output (kW)

Cumulative energy production (kWh)

Real-time website display usually includes AC watts output, insolation, wind speed, temperature, time, location, and digital pictures of the PV installation.

The monitoring system will include a high-quality data logger and communications equipment for displaying this information on the worldwide web or on-site computer terminal. This system provides a high-visibility means to communicate the system performance. Parameters from the system (as well as other messages) can be displayed. We will provide a data logging system which will include the following:

Multi Channel Data Logger to monitor the following parameters: Real-time Power, Sunlight, Wind Speed, Air Temperature and Instantaneous system output (kW) Cumulative energy production (kWh).

· Internet Broadcast Device and modem for data collection (Customer must provide Ethernet connection to internet & telephone line)

· Power supply, battery, NEMA3R enclosure, assembly, programming, Testing, and full documentation.

· Five years of Real-Time internet display with website hosting by Fat Spaniel Technologies.

· Five years of historical charting and data analysis.

· Complete custom integration of system data and website.

TurtleEnergy, through Fat Spaniel Technologies- the nation’s leading supplier of monitoring and instrumentation for PV systems can offer a full range of systems and services to include real-time displays, internet connectivity, etc. For a sample of other projects using this real-time website display technology, we invite you to visit our web site at www.TurtleEnergy.com and view the case studies for a history of performance on multiple systems.

Project Data

End-User: New Jersey Housing and Mortgage Finance Administration

Installer: Evco Mechanical

Location: Trenton, New Jersey

Date of install: July 2007

Size of system in kW: 103kW

Energy produced since installation~500MWh

Special Challenges Met: 

Project Brief:

Turnkey Delivery & Installation of a 103kW Photovoltaic System

• Guaranteed Power Capacity (103.01kW), measured at the inverter(s) input.

• Guaranteed Power Capacity (87.39kW), measured at the inverter(s) output.

• Estimated Capacity Factor (12.85%) and annual output (125,997kWh)

• Guaranteed PV Panel Degradation rate for 20 years (10%)

• PV Array Materials- Multi-Crystalline Silicon encapsulated in lead-free glass with biodegradable encapsulant (enables disposal in land fill rather than toxic waste),

Here are some other attributes of the PV Module (also see spec sheet). Greatest Power of Any Module Fewest mounting fasteners and external electrical connections per watt of array. High Efficiency Silicon Solar Cells High power per unit area in a long life, stable crystalline solar cell. High Module Voltage Allows integrators to “fine tune” the system by providing just the right number of modules to meet the specified power… Perfect for grid-connected and high voltage battery systems. Advanced Encapsulant Developed by RWE SCHOTT Solar, this encapsulation system has been shown to outperform traditional EVA. Double Glass Construction As a perfect moisture barrier, the glass-on-glass construction provides the longest possible module life. Internal Bypass Diode Protection Bypass diode protection every 18 cells in series. No-Lead Solder Modules are safe for disposal in any ordinary landfill. Quick, Polarized Connectors Array module-to-module wiring can be a snap Flex Interface System Enables wide range of interconnection options that can be tailored to the customer’s needs. Power Testing at the Connector Wire loss within the module to module wiring is already accounted for at the factory module tester. IEC 61215 Certified An international independent certification of module performance. UL 1703 Listing A world recognized authority on electrical safety… Makes approval a breeze. Class A Fire Rating Permits module mounting on any roof with no compromise in the roof’s fire rating. • Inverter: Satcon 100kW utility interactive inverter (most efficient inverter on the California Energy Commission eligible inverter list). • Structural Materials (see illustrations below) Entire Array is set at a fixed 5 degree tilt on a steel superstructure which has minimal penetrations through the roof (28 steel piers). Modules overhang the skylight, providing full winter sun penetration through skylights and allowing noontime shading to reduce heat gain in summer. Existing sloping roof has 3” of rigid insulation- this disallows conventional pv mounting hardware solutions, such as unirac or pro solar mounting rails due to shaft length of fasteners. Also, metal decking is inappropriate substrate to affix to due to thinness. TurtleEnergy TurtlEnergy LLC Linden Voice Fax Web Email 1900 Lower Road, New Jersey, 07036 908 397 5740 732 292 9491 www.TurtlEnergy.us John.Millard@TurtlEnergy.us 3’6” Steel Superstructure attaches to the existing structural trusses at their strongest point- the ridge beam. The Trusses occur 21’ on center, there are two penetrations at each truss, one on each ridge. (Trusses not shown for clarity.) 103kW PV Array overhangs ridges by 3’-6”. Summer high noon sun is shaded from the Callwall translucent panels but allows direct sun heating in the winter when the sun is lower. SUMMER SUN 45 Degrees WINTER SUN 25 Degrees The Schott Solar Panels are built with a structural aluminum extrusion as a frame which is designed to span the length of the Module on special supports for commercial pv systems. This frame carries the weight of the module from specially designed mounting pins which in this case, are locked into a bracket which is bolted to the structural metal (and not to a secondary racking system commonly found in residential pv applications) Mounting Pins Mounting Brackets TurtleEnergy TurtlEnergy LLC Linden Voice Fax Web Email 1900 Lower Road, New Jersey, 07036 908 397 5740 732 292 9491 www.TurtlEnergy.us John.Millard@TurtlEnergy.us (3.8.1 Continued) • Balance of system components: see attached specifications sheets • Configuation: including flat and tilt mounted systems: see above illustrations • Structural requirements: see above narrative • Operation and maintenance: the system is self cleaning due to the washing action of the rain over the 5 degree angle of the mounting structure. The monitoring system enables for periodic system checks from the desktop. Installation warrantee in New Jersey is for 5 years. • Typical Degradation (by Warrantee) is ½% / year. • Benefits specific to this system: see attached document on next page.

Letter from Installing Contractor to TurtleEnergy after persistent Inverter Problems were determined to be the cause of an electrical ground fault (that had been previously thought to be a wiring fault in the array).

" RE: SatCon Inverter Location: New Jersey Housing Mortgage Finance Agency Building- As you are aware, the SatCon.l00kW inverter installed at the New Jersey Housing and Mortgage Finance Agency has experienced numerous shutdown events since if was commissioned on November 20, 2008. Some of these shutdown events have been related to field conditions (e.g., ground faults) that were corrected, others have been the result of an, as yet, undiagnosed issue. When the inverter was first delivered, it had a number of defects that indicated the unit had never been factory tested under load (e.g., an improperly wired terminal block; a faulty contact in the DC disconnect switch; loose connections on the main control board; etc.). There were also problems with several of the PV panels (e.g., cracks, bad diode packs, etc.). The aforementioned problems were diagnosed and (apparently) repaired by Turtle Energy's representatives at the time of installation and during subsequent troubleshooting forays. And, because the problems were handled expediently and with exemplary care and concern, we (Evco Mechanical) decided to accept the equipment as is, and made our payment in good faith. However, it is now clear that something is still wrong at the site, and we implore each and every party involved in the design, installation and commissioning of this system to help us address this problem immediately. This is a sho'wease installation; it 'will generate more business for all involved. Vie cailiiot treat this as if it were a problem with just any array. This site is front-and-center with the Governor's (and many other state offi.cials) office(s). It would ill-behoove us all to neglect this issue. We respectfully request a plan of action from each of you as soon as possible. Thank you for your help. "

Architecture Firm: Bohlin Cywinski Jackson

Client: Clarion University

Site: Science & Technology Building

Project Data:

End-User: Science Department

Installer: Evco Mechanical

Location: Clarion Pa.

Date of install: August 2009

Size of system in kW: 

Energy produced since installation

Special Challenges Met: 

Project Brief

Project Summary: We designed, supplied and managed the construction of a 28kW Solar Energy System for Clarion University. I produced a well coordinated self ballasted mono crystalline solar PV System based upon the Solar World SW175 Module and a PV Powered 30kW PV Inverter. Working closely with Bohlin Cywinski Jackson's Structural Engineer, a distributed deadload was agreed to comply with wind uplift calculations we worked out a safe, maintenance free solution for the New Science Building.

Project Data

End-User:   Turtle & Hughes

Installer: SM Electric

Location: Linden, NJ

Date of install:  June 2007 – Nov 2007

Size of system in kW: 255kW

Energy produced since installation

Special Challenges Met: 1) Building had to be re-roofed

2) 208V Building needing larger wire size    3) Employed Interns from NJIT to layout mounting hardware 4) Tight deadline for installation due to rebate sunset.

Project Brief

Turtle & Hughes, headquartered in Linden, New Jersey, is a $303,000,000 multi-commodity procurement organization with a distribution center, seven additional branch locations, and 18 managed storerooms in the United State serving the industrial, automation, construction, commercial, electrical contracting, export, utility and data communications markets. Turtle Energy designed a Photovoltaic system to be installed at the headquarters in Linden using SM Electric (Union Contractor) who teamed with IBEW (local 102).

Turtle Energy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Management.

The building had a roof that had to be replaced prior to the installation of a Photovoltaic system and the roofing company was required warrantee the roof with the PV system on it. Turtle Energy engaged Harrison Hamnett, PC to verify compatibility of the roofing structure with the proposed Photovoltaic system. The system design was complicated by the fact that the building is 208V and this affects the size of the wire needed. Turtle Energy managed the installation of the mounting hardware and PV panels, the labor source employed for the summer were interns from New Jersey Institute of Technology who were Architecture majors. The project was on a tight deadline due to the rebate sunset.

The project commenced in June of 2007 and the system was commissioned in November of 2007. The size of the PV system for Turtle & Hughes is 255kW.

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented and Fat Spaniel data acquisition illustrations show snapshots of the actual energy generation by the PV system for Turtle & Hughes. These measurements are in compliance with the predicted analysis done by TurtleEnergy and in some cases slightly exceed the target energy output range. Data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. The installed PV system has successfully helped reduce the on-grid energy usage.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 225kw Inverter

Schott 330w Module

Schott Solar FS Mounting System

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

The New Jersey Clean Energy Program and Turtle & Hughes, Inc are in partnership constructing a 250kW Solar Electric System on the rooftop of 1900 Lower Road, Linden New Jersey. The project will generate 270,000 kWh from available sunlight per year and produce over half of the building's electricity needs. 800 Solar Panels generate 320W of electricity each and are mounted on penetrationless metal mounts on the roof and have a warranted life of 20 years. Electrical System: The building's electrical system will have a 225kW inverter interconnected on the customer side of the meter at the AC bus of the Switchgear. The Inverter is designed (as required by U L 1741) to cease operation within 2 cycles of a power outage. This prevents the possibility of the solar array harming a linesman who may be attending to the cause of the outage. The overcurrent protection devices in the system are sized according to National Electrical Code and the system is certified by Underwriters Laboratories. Mounting Structure: The mounting system for the solar panels is designed to support the solar panels on the roof without requiring attachment to the roof structure. This is possible with research and development of the mounting system in a wind tunnel under the supervision of civil and aeronautical engineers (see letter from Civil Engineer regarding the code compliance of the mounting structure for wind resistance).

Project Data

End-User:   Extrusion Technology

Installer: Sunlight Solar Energy

Location: 80 Trim Way, Randolph, MA 02368.

Date of install:  June 2006 – November 2006

Size of system in kW: 60kW

Energy produced since installation

Special Challenges Met: 1) Building roof structure had to be reinforced to withstand the weight of the PV system. 2) Wind loading for the location was 110 mph.

Project Brief

Extrusion Technology is a custom specialty extrusion company, where blocks of metal are taken and forced through a die to form it into the required shape. Turtle Energy designed a Photovoltaic system to be installed on the building. The installer for the project was Sunlight Solar Energy. Due to their location in Randolph, MA Turtle Energy suggested that they use the MA made product from Schott so that they could qualify far a larger rebate from the State.

Turtle Energy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Management.

The module and mounting hardware manufacturer provided wind analysis by a civil engineer. This analysis showed that the site required planning for 110mph wind loading consequently ballast had to be added to the Schott FS system. Gale Associates structural engineers advised that the roof structure be reinforced to ensure that it would support the PV system; this work had to be done prior to installation of the PV array.

The project commenced in July of 2006 and the system was commissioned in December of 2006. The size of the PV system for Extrusion Technology is 60kW.

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented and Fat Spaniel data acquisition illustrations show snapshots of the actual energy generation by the PV system for Extrusion Technology. These measurements are in compliance with the predicted analysis done by TurtleEnergy and in some cases slightly exceed the target energy output range. Data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. The installed PV system has successfully helped reduce the on-grid energy usage.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 60kw Inverter

Schott ASE 315w Module

Schott FS Mounting Hardware

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: RPF Industries.

Installer: American Energy Technology

Location:  Park Plaza 75 Main St, Milburn, NJ

Date of install: July 2006 –  Dec 2006

Size of system in kW: 63kW

Energy produced since installation

Special Challenges Met: 1) Deadline for sunset of the NJ rebate.  2) Fault with the utility supply of electricity to the building.

Project Brief

Park Plaza is an office building owned by Abe Silverstein Assoc.  Turtle Energy designed a Photovoltaic system to be installed at Park Plaza.

Turtle Energy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers (Stellar Energy Solutions)

Turtle Energy engaged Harrison Hamnett, PC to verify compatibility of the roofing structure with the proposed Photovoltaic system. American Energy Technology managed the project and communicated with the client. 2006 was a busy year for AET and a drawback was that the client for Park Plaza was concerned that his project was being delayed and was concerned that his NJ rebate would time out.

The project commenced in July of 2006 and was successfully completed in Dec of 2006. The size of the PV system for Park Plaza is 63kW. The Electrical Contractor of record was Forest Electric.

The project uncovered a utility phasing fault in the power supply to the building. The Satcon inverter kept shutting off because the quality of the electricity to the building from PSE&G was so poor. TE diagnosed the problem and the utility fixed the fault, subsequently Park Plaza has a much better electrical supply.

The Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented. The Fat Spaniel data acquisition illustrations show snapshots of the actual energy generation by the PV system for Park Plaza. These measurements are in compliance with the predicted analysis done by Turtle Energy and in some cases slightly exceed the target energy output range. Data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. The installed PV system has successfully helped reduce the on-grid energy usage and lower cost for Park Plaza.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 75kw Inverter

Schott ASE 315w Module

Schott Solar FS Mounting System

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: Service Tire Truck Center

Installer: 1Star Energy

Location: Millville, NJ

Date of install: 9/ 2006

Size of system in kW: 160kW

Energy produced since installation: ~1800 MWh

Special Challenges Met: First Solar Electric Project in Vineland Utility Territory

Project Brief

The Service Tire Truck Company is located in Millville, NJ. Service Tire is a company which recycles truck tires by re-treading them. Re-treading truck tires is an energy intensive industry. Service Tire expressed an interest in having a Solar Energy System which would provide them a cost reduction of their electric bill. A plan was presented to Service Tire to install a 165kw PV system designed and supplied by TurtleEnergy and installed by 1-Star Energy. Photovoltaic (PV) modules for this project were manufactured by General Electric (GE).

1-Star Energy president, Dave Rose provided valuable construction management and timely scheduling for the project. TurtleEnergy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers

Construction commenced in January 2006 and was completed in May of 2006.

TurtleEnergy provided oversight to ensure implementation of the project shop drawings. The complete project team consisted of the following:

1-Star Energy (Installation Contractor)

Todd Koenig Associates (Architect)

Harris Hamnett, PC (Structural Engineer)

Forest Electric (Electrical Contractor)

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented for the Service Tire project. The Fat Spaniel data acquisition system, logs the actual energy generation by the PV system. The resulting measurements are in compliance with the predicted analysis done by TurtleEnergy. The Fat Spaniel system data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals.

For additional information on product specifications see the appropriate cut sheets listed below.

GE PV Panel GE P165

SATCON 135kw Inverter

Uni-Rac Solar Mount (mounting hardware)

Fat {C}

Project Data

End-User: Tehama Tire

Installer: 1 Star Energy

Location: Red Bluff, CA

Date of install: June 2005 – Aug. 2005

Size of system in kW: 160kW

Energy produced since installation

Special Challenges Met: 100% of energy consumption powered by the sun

Project Brief

The Tehama Tire Company, located in Red Bluff CA was TurtleEnergy’s first California project and was installed by 1-Star Energy of Auburn, CA. Photovoltaic (PV) modules for this project were manufactured by General Electric (GE). Tehama Tire is a company which recycles truck tires by re-treading them. Re-treading truck tires is an energy intensive industry. The owner of Tehama Tire, Gary Gable required that 100% of his energy consumption be powered by the sun. 1-Star Energy presented TurtleEnergy with a two-phase plan to replace his electricity bill with power from the sun. This is the first phase of that plan to install a 160kw PV system designed and supplied by TurtleEnergy and installed by 1-Star Energy.

1-Star Energy president, Dave Rose provided valuable construction management and timely scheduling for the project. TurtleEnergy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Managers

Construction commenced in June 2005 and was completed in August of 2005. TurtleEnergy provided oversight to ensure implementation of the project shop drawings. The complete project team consisted of the following:

1-Star Energy (Installation Contractor)

Steve Fallon – Fallon Engineering (Structural Engineer)

Scott Godfrey – Hightech Electric Inc. (Electrical Contractor)

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented for the Tehama Tire project. The Fat Spaniel data acquisition system, logs the actual energy generation by the PV system. The resulting measurements are in compliance with the predicted analysis done by TurtleEnergy. The Fat Spaniel system data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals.

For additional information on product specifications see the appropriate cut sheets listed below.

GE PV Panel GE P165

SATCON 225kw Inverter

Uni-Rac Solar Mount (mounting hardware)

Fat Spaniel (remote monitoring system)

SMA Sunny 6000 Inverters

Project Data

End-User:   Wedgewood Plaza

Installer: American Energy Technologies

Location: Wayne, NJ

Date of install:  August 2007 – January 2008

Size of system in kW: 146kW

Energy produced since installation

Special Challenges Met: 1) Project was originally to use crystalline modules but results of the wind analysis lead to change to thin film.

 Project Brief

Wedgewood Plaza is a retail center in Wayne, NJ. American Energy Technologies provided customer liaison and project management. Turtle Energy designed a Photovoltaic system to be installed on the retail center. Nu-Tek Roof Systems installed the 1080 Uni-Solar PVL 136W panels.  VPV Electric completed the electrical work.

Turtle Energy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Management.

The project was originally a crystalline module project. Turtle Energy took engineering advice that caused a change to the type of module used, the wind analysis for the site was not compatible with crystalline and therefore the proposed Photovoltaic system was redesigned for thin film. Nu-Tek Roofing Systems cleaned the existing roof and installed the 1080 Uni-Solar PVL 136W Modules. VPV Electric wired up the project and AET provided project management.

The project commenced in August of 2007 and the system was commissioned in January of 2008. The size of the PV system for Wedgewood Plaza is 146kW.

Fat Spaniel’s integrated Satcon inverter direct internet-based monitoring system was implemented and Fat Spaniel data acquisition illustrations show snapshots of the actual energy generation by the PV system for Wedgewood Plaza. These measurements are in compliance with the predicted analysis done by TurtleEnergy and in some cases slightly exceed the target energy output range. Data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. The installed PV system has successfully helped reduce the on-grid energy usage.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon100kw Inverter

PV Powered 30kw Inverter

Uni-Solar 136w Module

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: Drill Construction

Installer: LB Electric

Location: 80, Main St, West Orange, NJ

Date of install:  July 2006 – Oct 2006

Size of system in kW: 55kW

Energy produced since installation

Special Challenges Met: 1) Project was delayed by Xantrax Inverter manufacturer, who shipped the wrong inverter and then a broken transformer.

 Project Brief

Drill Construction has their offices in West Orange, NJ. LB Electric provided customer liaison and project management and were also the electrical contractor of record. Turtle Energy designed a Photovoltaic system to be installed on the building.

Turtle Energy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Management.

The project commenced in July 2006 and the system was commissioned in October 2006. The size of the PV system for Drill Construction is 55kW.

The inverter for the project was originally specified to be a Satcon 50kW inverter. However the project schedule could not withstand the lead time for Satcon, therefore a Xantrax 45kW was ordered. Xantrax first sent an inverter with the wrong transformer in it, after which they sent another transformer that arrived in an undamaged box but the transformer inside was damaged. Finally they sent us the correct transformer. This all caused significant time delay and extra labor costs; however LB Electric and Turtle Energy were able to complete the project in time.

Fat Spaniel’s inverter direct internet-based monitoring system was implemented and Fat Spaniel data acquisition illustrations show snapshots of the actual energy generation by the PV system for Drill Construction. These measurements are in compliance with the predicted analysis done by TurtleEnergy and in some cases slightly exceed the target energy output range. Data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. The installed PV system has successfully helped reduce the on-grid energy usage.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 50kw Inverter

Schott ASE 315w Module

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: Yolo Medical Center

Installer: LB Electric

Location: 80, Main St, West Orange, NJ

Date of install:  July 2006 – Oct 2006

Size of system in kW: 55kW

Energy produced since installation

Special Challenges Met: 1) Project was delayed by Xantrax Inverter manufacturer, who shipped the wrong inverter and then a broken transformer.

Project Brief

Drill Construction has their offices in West Orange, NJ. LB Electric provided customer liaison and project management and were also the electrical contractor of record. Turtle Energy designed a Photovoltaic system to be installed on the building.

Turtle Energy undertook a detailed analysis of the site. This analysis was comprised of the following steps and implementation.

Shading Analysis

Optimal System Design and Concept Planning

Industrial Design of the Components of the System

Multi-Disciplinary Coordination with Architects, Structural Engineers, Electrical Engineers, and Construction Management.

The project commenced in July 2006 and the system was commissioned in October 2006. The size of the PV system for Drill Construction is 55kW.

The inverter for the project was originally specified to be a Satcon 50kW inverter. However the project schedule could not withstand the lead time for Satcon, therefore a Xantrax 45kW was ordered. Xantrax first sent an inverter with the wrong transformer in it, after which they sent another transformer that arrived in an undamaged box but the transformer inside was damaged. Finally they sent us the correct transformer. This all caused significant time delay and extra labor costs; however LB Electric and Turtle Energy were able to complete the project in time.

Fat Spaniel’s inverter direct internet-based monitoring system was implemented and Fat Spaniel data acquisition illustrations show snapshots of the actual energy generation by the PV system for Drill Construction. These measurements are in compliance with the predicted analysis done by TurtleEnergy and in some cases slightly exceed the target energy output range. Data monitoring results are available both on a real-time and historical basis. Measurements can be viewed on daily, weekly, monthly, yearly or lifetime intervals. The installed PV system has successfully helped reduce the on-grid energy usage.

For additional information on product specifications see the appropriate cut sheets listed below.

Satcon 50kw Inverter

Schott ASE 315w Module

Fat Spaniel (remote monitoring system)

Multi-Contact Connectors

ILSCO Direct Bury Grounding Lugs

Project Data

End-User: Private Homeowner

Installer: Global Home Improvement

Location: Manasquan, New Jersey

Date of install: August 2013

Size of system in kW: 12kW

Energy produced since installation; 18MWh

Special Challenges Met: Re-Roofing Surprises

Project Brief:

Project Data

End-User: Private Homeowner

Installer: Global Home Improvement

Location: Manasquan, New Jersey

Date of install: August 2013

Size of system in kW: 12kW

Energy produced since installation; 18MWh

Special Challenges Met: Re-Roofing Surprises

Project Brief:

TurtlEnergy Total Distributed Generation Project Quality Inventory:

 Client Items:

1. What are the customer's goals for the project? (PR, maximum array size, CEC output, $/kW, etc.)

2. What is their energy output priority?

3. (Total year max, summer peak, other peak?)

4. Proposed schedule?

5. Any special time constraints?

6. Prevailing wages, union requirements Inspection requirements other than customer, building department, or utility?

7. List any non-standard permitting requirements. Bonding requirements (bid, performance, payment, etc.) Taxes ?

8. Sales Tax exemptions:

9. General Site Items: Who is the building / facility contact and phone number?

10. What is the overall building age?

11. Will there be any special consideration required for the system by thelocal utility or the fire department?

12. Budgetary Proposal

13. Where will the equipment be staged before installation?

14. Is there a secure location where we can store tools?

15. Is there a loading dock?

16. If this is a carport or ground mount, what is the soil type?

17. What facilities can TurtlEnergy use during installation (utilities, sanitary, parking, phone, etc.)?

18. Where will the installation groundwork take place? Is there landscaping to consider?

19. Underground utilities?

20. What are allowable work hours?

21. Are there any difficulties in crew accommodations

22. (i.e. remote location, expensive area, etc.)

23. Is the any special information regarding geographic area, including descriptions of historical microclimates, that may affect system performance?

24. Any special site issues (i.e. relocate trees, specific grading requirements, etc.)?

Array Items:

25. Have you created, or do you have, a CURRENT drawing of each proposed PV installation site?

26. Is this drawing to scale? If not, are all dimensions given?

27. If this drawing is to scale, is the scale indicated?

28. Is "North" indicated?

29. Have you noted if this is "true" or "magnetic" north?

30. Are all obstructions deemed to cause interference or shading noted?

31. Are all obstructions dimensioned?

32. Do all obstructions include a height measurement?

33. Are parapet heights noted?

34. Have you noted what modules are to be used?

Roof Items:

35. What is the roof type?

36. If standing seam, do you have the manufacturer and type?

37. What is the approximate age of the roof?

38. What is the access to the roof?

39. Have you noted the placement and orientation of slopes, ridges and swales?

40. Where will the conduit and wire run? Where will it enter the building?

41. Who installed the roof (name and contact information, if available)? Is it still under warranty?

42. Have you noted the overall magnitude and direction of the roof slope?

43. For penetration systems, what is access to the underside of the roof like?

44. What is the structure and substrate of the roof (i.e., where are the trusses located, etc.)?

Electrical Items:

45. Where will the inverter be mounted? Indoor or outdoor?

46. What kind of space is available for wall mounting equipment indoors?

47. What is the approximate distance from the array to the inverter?

48. Type of panel? (Make, Model Number, Breaker Type, Surface or Flush mount, etc.)

49. What is the voltage and configuration (120/240, 208 delta, 480 wye, etc.)?

50. What is the rating (Amps) of the panel?

51. Are there existing breakers available? (Note size and whether they are adjustable trip. Also, Amp Interrupting Capacity (AIC) is good if available).

52. Are there existing breaker spaces available?

53. What is the rating on the main breaker (Amps and trip setting)?

54. What is the rating of main incoming breaker as well as any other generating systems connected to the panel?

55. How do these compare to the bus rating?

56. Who is the local utility and are there special metering requirements?

57. Are there electrical drawings of the facility?

58. Are there special aspects of the electrical distribution? (e.g. a transfer switch that will isolate the proposed panelboard, other on-site generation, specific customer requirements)

59. Where will the kWh meter be located in relation to the panel and the inverter?

60. What is the approximate wiring distance from the inverter to the panel?

61. How difficult will it be to get to the panel? Are there any noticeable entrances?

62. Is there a lot of conduit congestion?

63. Are there pre-existing conduits to the roof area?

64. Any special requirements or restrictions on the type of conduit?

65. Does the customer have an electrical contractor that they work with?

Data Acquisition System Items: Basic Package:

66. Is there an available phone line for the DAS?

67. Is there an available area for the data controller? (Can be indoors or out)

68. Is there 120 VAC available for the data controller?

69. Internet Package & Internet DAS Plus Package: Is there an available phone line for the DAS?

70. Is there an available area for the data controller? (Can be indoors or out)

71. Is there 120 VAC available for the data controller?

72. Is there an available area for the IBD? (Can ONLY be indoors)

73. Is there 120 VAC available for the IBD? (If data controller and IBD are in close proximity, (1) 10 W 120 VAC connection can be used)

74. Is there an Ethernet connection to the IBD?

75. Internet DAS Plus with Kiosk Package: Is there an available phone line for the DAS?

76. Is there an available area for the data controller? (Can be indoors or out)

77. Is there 120 VAC available for the data controller?

78. Is there an available are for the IBD? (Can ONLY be indoors)

79. Is there 120 VAC available for the IBD? (If data controller and IBD are in close proximity, (1) 10 W 120 VAC connection can be used)

80. Is there an Ethernet connection to the IBD?

81. Is there an inside area for the Kiosk?

82. Is there 120 VAC to the Kiosk?

Photo Items:

83. Electrical Room, multiple angles

84. Electrical Panel or other tie-in location and it's accessibility

85. Array Area, multiple angles

86. Staging Area, multiple angles

87. Utility Only:

88. Transformers: especially Oil Filled Transformers (do not locate inverters near)

89. Substation

90. Any objects that may interfere with or enhance conduit routes (i.e. catwalks, existing conduit, a wall that must be penetrated)

91. Enclosures: If necessary items have not been enclosed, please list the item, date engineering will receive it, and how it will be transmitted:

COMMISSIONING SCHEDULE

Prior to System Substantial Completion EPC Provider technical personnel, with the assistance of the equipment manufacturer(s) as needed, will perform a complete commissioning of the Generating Facility following the Commissioning procedures outlined in this Attachment as well as other standard tests, inspections, safety and quality checks.   All testing and commissioning will be conducted in accordance with the manufacturer’s specifications.  Owner reserves the right to have the testing and Commissioning results verified by the Commissioning Engineer.

These Commissioning testing procedures for photovoltaic systems and major components are intended to determine system performance to the specification.  The tests are designed to verify that the system, as installed, is safe for personnel as well as equipment, and to establish or verify system operation.  The tests shall be used to determine actual post-construction operational, performance, and safety characteristics.  [These tests are based in part on the draft IEEE Recommended Practice document (P 1373, June 1997) and focus on utility PV acceptance tests.]

For identification purposes, Owner or its agent, EPC Provider or its agent, and 3rd-party engineer are identified as follows:

1.    Project Informatio

2.    System Description

Tracking plane, tilted Axis Axis Tilt 3° Axis Azimuth -20°

Rotation Limitations Minimum Phi -45° Maximum Phi 45°

Backtracking strategy Tracker Spacing 4.19 m Collector width 1.68 m

Inactive band Left 0.01 m Right 0.01 m

Horizon Average Height 3.7°

Near Shadings Adjoining Vegetative Buffers

PV Arrays Characteristics (2 kinds of array defined )

PV module Si-mono Model SW 235 mono

Manufacturer SolarWorld

Array#1: Number of PV modules In series 13 modules In parallel 1833 strings

Total number of PV modules Nb. modules 23829 Unit Nom. Power 235 Wp

Array global power Nominal (STC) 5600 kWp At operating cond. 4939 kWp (50°C)

Array operating characteristics (50°C) U mpp 353 V I mpp 13996 A

Array#2: Number of PV modules In series 13 modules In parallel 97 strings

Total number of PV modules Nb. modules 1261 Unit Nom. Power 235 Wp

Array global power Nominal (STC) 296 kWp At operating cond. 261 kWp (50°C)

Array operating characteristics (50°C) U mpp 353 V I mpp 741 A

Total Arrays global power Nominal (STC) 5896 kWp Total 25090 modules

Module area 42068 m²

Array#1 : Inverter Model Sunny Central 500-HE-US

Manufacturer SMA

Characteristics Operating Voltage 300-600 V Unit Nom. Power 500 kW AC

Inverter pack Number of Inverter 10 units Total Power 5000 kW AC

Array#2 : Inverter Model Sunny Central 250U

Manufacturer SMA

Characteristics Operating Voltage 300-600 V Unit Nom. Power 250 kW AC

1.    Normal Operating Model

Main system parameters System type Grid-Connected

Horizon Average Height 3.7°

PV Field Orientation tracking, tilted axis, Axis Tilt 3° Axis Azimuth -20°

PV modules Model SW 235 mono Pnom 235 Wp

PV Array Nb. of modules 25090 Pnom total 5896 kWp

Inverter Model Sunny Central 500-HE-US Pnom 500 kW ac

Inverter Model Sunny Central 250U Pnom 250 kW ac

Inverter pack Nb. of units 11.0 Pnom total 5250 kW ac

User's needs Ext. defined as file Workbook14.csv global 9547 MWh/year

Horizon Average Height 3.7° Diffuse Factor 1.00

Albedo Factor 100 % Albedo Fraction 0.85

Height [°]        Azimuth [°]

5.0        -120

3.0        -40

3.0         40

5.0        120

PV Array loss factors

Thermal Loss factor Uc (const) 23.2 W/m²K Uv (wind) 4.5 W/m²K / m/s

=> Nominal Oper. Coll. Temp. (G=800 W/m², Tamb=20°C, Wind velocity = 1m/s.) NOCT 46 °C

Wiring Ohmic Loss Array#1 0.43 mOhm Loss Fraction 1.5 % at STC

Array#2 8.2 mOhm Loss Fraction 1.5 % at STC

Global Loss Fraction 1.5 % at STC

Array Soiling Losses Loss Fraction 3.0 %

Module Quality Loss Loss Fraction 1.5 %

Module Mismatch Losses Loss Fraction 2.0 % at MPP

Incidence effect, ASHRAE parametrization IAM = 1 - bo (1/cos i - 1) bo Parameter 0.05

System loss factors

AC wire loss after inverter Wires 1 m 2x1200 mm² Loss Fraction 1.6 % at STC

External transformer Iron loss 5817 W Loss Fraction 0.1 % at STC

Resistive/Inductive losses 0.1 mOhm Loss Fraction 1.0 % at STC

2.    BILL OF MATERIALS

3.    System Specifications

Module STC Rating

240W &250W

Module PTC Rating TBD

Inverter CEC Efficiency 98%

Overall Array STC (DC kW)  ~6000

Overall Array PTC (AC kW) ~5000

Predicted KWh/yr (typical) 8500 MWH

235W SOLAR WORLD W SMA500HE-US + SMA250HE –US

Balances and main results

GlobHor    T Amb    GlobInc    GlobEff    EArray    E_Grid    EffArrR    EffSysR

kWh/m²        °C          kWh/m²     kWh/m²      kWh        kWh            %              %

Jan     55.1          -1.05                73.8         69.9     394393    381851        12.70     12.29

Feb     63.5           0.57              81.0        77.3      433496    419504       12.72     12.31

Mar    113.4             6.84           144.3      138.9     753308    728240        12.41         12.00

Apr    149.4          12.85          184.9      179.1     932859    901521        11.99      11.59

May     184.9          15.53          221.1      214.2     1100382  1062997      11.83         11.43

June     182.6          21.77          212.6      205.7     1017923    984941      11.38         11.01

July     195.8          25.27          231.2      224.3     1090516  1055039      11.21         10.85

Aug    153.0           24.97          181.2      175.1       845851    818980       11.10         10.75

Sep    110.5          18.72          133.2      128.1       647456    627169       11.55        11.19

Oct    112.0          13.45          150.6      145.0       754369    731104       11.91        11.54

Nov     64.2            8.91            87.9        83.6       448333    434562        12.13        11.76

Dec     49.6            2.28            70.0        66.4       365911    354876        12.42        12.04

Year      1434.2           12.57        1771.8    1707.7    8784798   8500783      11.79       11.41

Legends: 

GlobHor: Horizontal global irradiation

T Amb: Ambient Temperature

GlobInc: Global incident in coll. plane

GlobEff: Effective Global, corr. for IAM and shadings

EArray: Effective energy at the output of the array

E_Grid: Energy injected into grid

EffArrR: Effic. Eout array / rough area

EffSysR: Effic. Eout system / rough area

DAS Commissioning

1.    DAS wiring

Verify that there are no loose or damaged data wires.  Verify that DAS wiring is tight and neat.    

2.    Meteorological station

Verify that meteorological station is sited in a location within the Generating Facility footprint that is representative of the entire Generating Facility, and is free of shading or obstruction.  Verify that that the meteorological station is mounted properly and secure.  Verify that the meteorological station junction box wiring is tight and neat.  Verify that the meteorological station is operating properly and calibrated.

3.2.1    Insolation Sensor

Verify that there is an insolation sensor for each plane of array applicable to the Generating Facility, as well as one sensor fixed in a horizontal plane.  Verify that all insolation sensors are properly adhered, cleaned, and calibrated.

3.2.2    Anemometer

Verify that anemometer is calibrated, properly installed, and functioning properly.

3.2.3    Temperature Probes

Verify that there is a temperature probe measuring both the ambient temperature and the cell temperature, and that both probes are functioning.

3.    DAS Communication  

Verify that cell or DSL modem is functioning properly.

4.    Battery back-up

Verify battery back-up is operating

5.    Time / Date 

Verify that time / date is properly set.

6.    Data Logger 

Verify that data, from each sensor, is being logged and saved.  

7.    On-Site Meter Display 

Verify that meter display is outputting data - including kW, kWmax, and kWh (total).

8.    Power Metering 

Verify that meter is mounted, calibrated, and is working properly.  Verify that pulser assembly is calibrated and functioning (if applicable).

9.    Verify data read.

Supply 3 days of data verified with a meter read.

4.    Visual and Mechanical Commissioning

1.    Visual Inspections – General

Make sure all disconnect switches are open and power is not applied.

4.1.1    PV Modules and Module Wiring

Verify that all connectors are properly mated, module cables are properly secured to module frame, no debris on module surface, no physical damage to module frames or laminates, and ground wire and lug are securely attached to module frame.

4.1.2    Source Circuit (Combiner) Junction Boxes

Verify that all connectors are secured, field wiring terminations are tight, field wiring is properly polarity-marked with colored tape or jacket color, ground wire is securely attached, labels are in place, and all covers are secured.

4.1.3    DC and AC Disconnect Switches

Verify field wiring terminations are tight, field wiring is properly polarity-marked with colored tape or jacket color, conduit connections are tight and bushings uses (if applicable), ground wire is securely attached, and all covers are secured.

4.1.4    Inverter(s)

Verify field wiring is routed properly, field wiring terminations are tight, field wiring is properly polarity-marked with color tape or jacket color, conduit connections are tight and bushings used (if applicable), ground wire is securely attached to inverter, labels are in place, and all covers are secured.

4.1.5    Alignment of Structural Components

Visually check that the rows of modules have been installed in straight lines that are parallel to each other.  Check that the rows are level, and do not contain excess waviness..  Verify field wiring is routed properly, field wiring terminations are tight, field wiring is properly polarity-marked with color tape or jacket color, conduit connections are tight and bushings used (if applicable), ground wire is securely attached to inverter, labels are in place, and all covers are secured.

2.    Visual Inspections – Tracking System [if applicable]

4.2.2    Torque tube bearing caps

Ascertain that each torque tube bearing cap ([   ] caps per torque tube) has been installed correctly.

4.2.3    Bolts and Retaining Nuts

Check all of the anchor-bolts and nuts for proper installation and check for tightness of nuts on the bolts.  (Typically [    ] per array structure.)

4.2.4    Motors

4.2.5    LINKAGES

Visually check that the linkages are properly installed.

Slew Rings/ Gear Drives are properly greased & sealed.

Hydraulic lines should be fastened to the support structure at regular intervals.

4.2.6    Installation of Dampers, check for proper tension/ compression in dampers to preventive harmonic movement of the trackers.

4.2.7    Alignment of Structural Components

Visually check that the rows of modules have been installed in straight lines that are parallel to each other.  Check that the rows are level, and do not contain excess waviness due to torque tube loading.  Verify field wiring is routed properly, field wiring terminations are tight, field wiring is properly polarity-marked with color tape or jacket color, conduit connections are tight and bushings used (if applicable), ground wire is securely attached to inverter, labels are in place, and all covers are secured.

4.2.8    Tracking.  (This part of the inspection is accomplished over an entire day.)

Observe each array structure during the morning, mid-day, and afternoon.

The tilt of the modules on the torque tubes should be the same on each row.

When the sun is at it’s zenith, the modules should be level.

Note:  The torque tubes rotate in unlubricated Teflon bearings.  Some snapping, popping, or cracking noises are normal during movement of the torque tubes.

4.2.9    During installation of the trackers, preventative action for known failure modes must be taken by the installer. These failure modes and their respective preventative actions are listed below:

5.    Electrical Commissioning

Electrical Check-Out

Make sure all disconnect switches are open and power is not applied.

5.1.1    Resistance to Ground

Measure hardware components metal frames and housing resistance to ground.

1.    Array Structure

2.    Junction Box

3.    DC Disconnect Frames

4.    Inverter Frame

5.    AC Distribution Panel

6.    Other

5.1.2    Disconnect Switches

Make sure all disconnect switches are open, fuses are removed from combiner boxes, and that power is not applied.

5.1.3    Source Circuit Voltage Polarity Tests

Measure and record in section #####, each source circuit’s open circuit voltage and note the amplitude and polarity.  Each string must be within three percent of the mean.  Current Measurement are made later after all source circuit polarity has been verified.  Complete this section for each inverter first before moving to starting the inverter system.

5.1.5    Combiner Box Fuse

Insert Comber Box fuses

5.1.6    DC Disconnect Switches

Verify the polarity and open-circuit DC voltage magnitude of PV input to switch are correct for each disconnect switch.

5.1.7    Activate DC Disconnect Switches

Turn on DC Disconnects (not the inverter’s DC interface).

5.1.8    Inverter DC Input

Verify polarity and DC voltage magnitude at the DC Interface are correct.

5.1.9    Inverter AC Input

Verify polarity and AC voltage magnitude of utility connection to inverter are correct.

2.    System Operational Tests 

5.2.1    Apply AC power to the inverter (close the circuit breaker and/or AC disconnect switch). 

5.2.2    Apply DC power to the inverter (close DC disconnect switch)

3.    System Operation

5.3.1    With the system operating verify that system AC output ceases when the DC disconnect switch is shut off.

5.3.2    With the system operating verify that the system AC output ceases when the AC disconnect switch is shut off.

1.    System Data

5.4.1    Commissioning Tests – Before Substantial Completion

Open Circuit Voltage, Inverter, and String I-V Curve Trace tests shall be performed in accordance with procedures detailed in this section 5.5.1, and test data shall be recorded in Section 5.5.3, prior to commissioning of the Generating Facility.  

Pre-Substantial Completion Commissioning Test Procedures:

5.4.1.1    Open Circuit Voltage Test

Purpose:    Open Circuit Voltage Testing provides a simple method to determine that all strings are properly connected (module and string polarity) and that all PV modules are producing an appropriate voltage level.

Scope:    All Strings

Party:    EPC Provider technical personnel

Schedule:    During Commissioning

Equipment/Materials:

1.    rubber insulating gloves

2.    voltmeter with an accuracy of at least 1 percent of reading

3.    fuse puller

4.    infrared thermometer or thermocouple

5.    PV specification for Voc as a function of temperature

6.    jumper wire

Conditions:

This test will be conducted under full sun (>500 W m 2) and stable sky conditions, generally between the hours of 10:00 a.m. and 2:00 p.m.  If such conditions are not available due to the season of the year, then the EPC Provider shall not conduct such test until the earlier of the date on which such conditions exist and 3 business days following the date on which the test would otherwise have been conducted.  If, upon the expiration of the foregoing period, such conditions are still not available, then the test will be conducted under stable sky conditions with a minimum irradiance of 200 W/m2; provided, however, that Owner shall have the option to cause the EPC Provider to conduct any such test on the original date therefor regardless of the sky conditions on such date.

Procedure:

7.    Measure the temperature of the PV modules using an infrared thermometer or thermocouple. (It is sufficient to measure the temperature of 2-3 modules and take the average).

8.    Calculate Expected Voc:  Referring to the PV manufacturer supplied equation for Voc as a function of temperature, calculate the expected Voc of each string.

9.    Remove Fuses:  Wearing rubber insulating gloves and using a fuse puller, carefully remove the fuses from the combiner box.  Failure to remove the fuses will result in identical voltage measurements for every string since they are in parallel with the fuses in place.

10.    Test String Voltages:  Place the positive lead on the fuse block of the string you are testing while the negative lead is attached to the negative block.  Continue testing each string by moving to each positive string fuse block.  Test and record the voltage of each electrical string.

Criteria:

11.    For stable sky conditions and irradiance above 500 W-m-2, string voltages should conform to within 5% of expected voltage as calculated in Step 2 above and each string should conform to within 2% of the average string voltage in the same combiner box under identical temperature and irradiance conditions. 

12.    For irradiance less than 500 W m 2or for unstable sky conditions (if irradiance changes by more than 10%, or ambient temperature changes by more than 5°C), compare each string’s measured voltage to periodic measurements on a known good (reference) string. The reference string must be measured at irradiance above 500 W m 2 and its measured voltage must be within 5% of the voltage calculated using Step 2 above.  Voltage on non-reference strings should be within 5% of the reference string voltage under the same temperature and irradiance conditions.

13.    For irradiance less than 200 W m 2, test results may be used only to confirm proper string connection, and not to evaluate voltage performance.

5.4.1.2    Inverter Commissioning

Purpose:    Verify the proper operation of the inverter systems

Scope:    All inverters

Party:    EPC Provider and/or manufacturer, with EPC Provider supervision

Schedule:    At inverter start-up

Equipment/Materials:

14.    rubber insulating gloves

15.    digital multi-meter an accuracy of at least 1 percent of reading for voltage

16.    other equipment as required by manufacturer

Procedure:    Follow all manufacturer’s guidelines for inverter start-up and commissioning, including verification of safety and control features.

Conditions:    No special conditions apply.

Criteria:    The inverter and controls should operate as stated in the purchaser or manufacturer specifications.

Comments:    Remote functions should only be tested on those systems that will utilize this feature.

5.4.1.3    String I-V Curve Test

Purpose:    I-V curves are useful for identifying array problems and characterizing array performance. The purpose of this test is to compare strings on a qualitative basis. For this test, I-V Curve Traces will be taken on a sample size consisting of all strings in 10% of all combiner boxes . I-V Curve Traces quantify actual photovoltaic module or string characteristics.

Scope:    A sample size consisting of a sample of all strings in 10% of all combiner boxes.

Party:    EPC Provider technical personnel

Schedule:    During Commissioning

Equipment/ Materials:    

17.    rubber insulating gloves

18.    I-V Curve Tracer or similar instrument

Procedure:

19.    Follow the manufacturer’s procedures for use of the I-V curve tracer.  

20.    Isolate the portion of the array of interest (plus and minus leads) from the inverter (a DC disconnect switch may suffice) and from other array segments. Connect the curve tracer load to the array leads (be aware of array and load polarities). Sweep the load such that it operates the array over its range of Voc and Isc (or as the load will allow). Record voltage and current readings for at least 10 steps.

21.    Along with the series of current voltage pairs, array and ambient conditions should be recorded for each curve including:

-    Irradiance (of the appropriate components and orientation)

-    Module Temperature

-    Ambient Temperature

-    Wind Speed (Optional)

-    Date and Time

22.    An indication of irradiance stability, such as pre and post curve irradiance, may also be recorded and is especially important if the curve takes more than one second.

23.    The measurement equipment must be capable of monitoring the array with sufficient speed and accuracy. During the curve sweep, typically only the array current and voltage are measured, with irradiance stability measurements taken before and after the curve, and the remaining parameters measured once before or after the curve.

Conditions:

24.    I-V curves must be taken under clear and stable sky conditions. For this test, irradiance must be above 500 W m 2.

25.    A reasonable attempt will be made to perform this test under ideal sky conditions; however, if ideal weather is not anticipated because of seasonal changes, the test will not be required for acceptance.

Criteria:

The string Voc should meet the criteria defined in Section 1 – Open Circuit Voltage Test above. The string Isc should meet the criteria defined below:

26.    Under sky conditions of 500 W/m2 or greater, the measured current should be within 5% of the expected Isc calculated using equation below:

Where:

27.    n = number of modules in parallel in test segment

28.    Isc, expected = expected short-circuit current of the test segment, A

29.    Isc, REF = module short-circuit current at some specified reference conditions, A

30.    G = measured plane of array irradiance, W-m-2

31.    GREF = irradiance at some specified reference conditions, W-m-2

32.    0.95 = factor to account for soiling, misalignment, and other factors.

33.    Under sky conditions of less than 500 W/m2, the measured short circuit current should be within 10% of the Isc calculated using the above equation.

All I-V curves should be similar in shape (other than differences due to changes in irradiance or temperature).

This test will be conducted under full sun (>500 W-m-2), generally between the hours of 10:00 a.m. and 2:00 p.m.  If such conditions are not available due to the season of the year, then the EPC Provider shall not conduct such test until the earlier of the date on which such conditions exist and 3 business days following the date on which the test would otherwise have been conducted.  If, upon the expiration of the foregoing period, such conditions are still not available, then the test will be conducted under stable sky conditions with a minimum irradiance of 200 W/m2; provided, however, that Owner shall have the option to cause the EPC Provider to conduct any such test on the original date therefore regardless of the sky conditions on such date.

Comments:    If results show anomalies, including fill factor, voltages, or currents outside expected limits or humps on the curve, then investigate for bypass diode conduction, out-of-tolerance module performance, or other possible problems.  Rectify any flaws and re-test.

5.4.2    Operating Verification Tests – After Substantial Completion, Before Final Completion

Operating Current and Operating Voltage tests shall be performed in accordance with procedures detailed in this section 5.5.2, and test data shall be recorded in Section 5.5.3, prior to Final Completion of the Generating Facility.  

5.4.2.1    Operating Current and Operating Voltage Test

Purpose:    The purpose of this test is to ensure that all strings are producing an adequate and consistent operating current and voltage.

Scope:    All strings, after connection with utility grid and inverter start-up

Party:    EPC Provider technical personnel

Schedule:    After Substantial Completion (Commissioning), before Final Completion

Equipment/Materials:

34.    rubber insulating gloves

35.    DC clamp-on ammeter, 0-40 A scale with 2 per cent. of full scale accuracy

Procedure:

36.    Start the Inverter:  Start the inverter if it is not already running, making sure all fuses are installed.  Wait 5 minutes for the power tracker to stabilize.

37.    Prepare for Readings:  Open the combiner box, turn on the ammeter, and carefully zero the meter.  Keep the clamp away from large bundles of wire, as they will affect the zero, and therefore the actual reading on the meter.

38.    Record the “Zero” Value:  Wearing rubber insulating gloves, place the meter near a string’s homerun wire.  Record the “zero” value.

39.    Record the Current Value:  While still wearing gloves, clamp the meter on each service loop in the box, recording the current readings.

40.    Calculate Actual Current:  Calculate and record the actual string currents as the difference between the string current reading and the “zero” value.

Example:

“Zero” value = 0.3 A

Current reading = 3.0 A

Actual Current:  3.0 A - 0.3 A = 2.7 A

41.    Record the Current Voltage Value:  While still wearing gloves, measure the voltage across a closed breaker

Conditions: Measurements will be made during clear and stable sky conditions.  The total inverter output should be at least 50% of the aggregate rating of the active inverters.  This test will be conducted under full sun (>500 W-m-2), generally between the hours of 10:00 a.m. and 2:00 p.m.  If such conditions are not available due to the season of the year, then the EPC Provider shall not conduct such test until the earlier of the date on which such conditions exist and 3 business days following the date on which the test would otherwise have been conducted.  If, upon the expiration of the foregoing period, such conditions are still not available, then the test will be conducted under stable sky conditions with a minimum irradiance of 200 W/m2; provided, however, that Owner shall have the option to cause the EPC Provider to conduct any such test on the original date therefore regardless of the sky conditions on such date.

Criteria: Under clear and stable sky conditions with irradiance greater than 500 W m 2, current readings within each combiner box should be within 5% of the average under identical sky conditions.  A reasonable effort shall be made to conduct this test under conditions with irradiance greater than 500 W m 2, however, if such conditions are not available in the commissioning period, then the Current Test will be performed as a sign-of-life test only, without the 5% criteria.

5.4.2.2    System Output Verification

Purpose:    Verify the kWh output of the Generating Facility to system design

Scope:    the Generating Facility

Party:    EPC Provider, with Owner and/or 3rd-party engineer supervision

Schedule:    After Commissioning, before Final Completion

Equipment/Materials:

42.    functioning DAS with pyranometer measuring irradiance in the plane of the array(s) of the Generating Facility providing 15-minute interval data.

Procedure:  Record DAS system for 5 continuous, uninterrupted days and compare actual system output to expected output per system design under recorded insolation for same time period.  

Conditions:    No special conditions apply.

Project Data

End-User: Plymouth Board of Education

Installer: Safari Energy

Location: Plymouth, Connecticut

Date of install: 5/ 2015

Size of system in kW: 260kW

Energy produced since installation: TBD

Special Challenges Met: Shading Analysis

Project Brief:

  This Memorandum of Understanding (“MoU”) is entered into by and between the Town of Plymouth, Connecticut Board of Education (“Plymouth BoE”), with offices at 77 Main Street, Terryville, Connecticut 06786, and PhosEnergy LLC (“PhosEnergy”), with offices located at 29 South Street, Manasquan, NJ 08736. Plymouth BoE and PhosEnergy are referred to collectively herein as the (“Parties”).                

WHEREAS, the Connecticut Light and Power Company (“CL&P”), pursuant to a Request for Proposals (“RFP”) in furtherance of the “Low and Zero Emissions Renewable Energy Credit Program” (the “Program”) established pursuant to Conn. Gen. Stat. § 16-244(r), 16-244(s) and 16-244(t), conducted a competitive bidding process in order to determine winning bidders based on lowest price and compliance with the terms and conditions of a fully executed Standard Contract for the Purchase and Sale of Connecticut Class I Renewable Energy Credits from Low and Zero Emission Projects (“the Projects”).  Based on bids submitted by PhosEnergy, CL&P has awarded PhosEnergy [_____] Standard Contracts for the Purchase and Sale of Connecticut Class I Renewable Energy Credits associated with Low and Zero Emission Projects that are being proposed for installation on or adjacent to four schools in the Town of Plymouth, specifically Terryville High School, Eli Terry Middle School, Harry S. Fisher Elementary School and Plymouth Center School; and                

WHEREAS, the Town of Plymouth, Connecticut held a Town Council Meeting on June 4, 2013 and voted unanimously to grant PhosEnergy status as Authorized Developer in order to permit PhosEnergy to submit bids into the Program, in response to the RFP; and     WHEREAS, Plymouth BoE and PhosEnergy desire to confirm the major terms under which the Projects will be designed, built, maintained and operated at the specified schools or sites; and    

WHEREAS, PhosEnergy has proposed to Plymouth BoE a competitive electricity pricing plan that will reduce Plymouth BoE’s price of electricity below current utility prices and will limit long term future electricity price increases; and    

WHEREAS, the Program requires certain timely responses from PhosEnergy during the Month of August 2013, in order to confirm the award of the Contracts, pursuant to the RFP.     Now, therefore, time being of the essence, and in consideration of the foregoing recitals, Plymouth BoE and PhosEnergy have entered into this MOU in order to advance their respective interests, and hereby agree as follows:     1.              The Parties will commence power purchase agreement (“PPA”) and site lease negotiations in good faith and as follows:  within five (5) business days after the execution of this MoU, PhosEnergy shall provide to Plymouth BoE a proposed PPA and lease agreement, incorporating the following major terms:  SOLAR POWER PURCHASE AGREEMENT  MAJOR TERMS  PPA Parties:                

PhosEnergy LLC or “Seller”, as defined in the PPA; Plymouth BoE or “Host Customer” as defined in the PPA.  

Term:                          20 years.  

Sites/Solar Systems:       1.     Terryville High School;  2.     Eli Terry Middle School;  3.     Harry S. Fisher Elementary School;  4.     Plymouth Center School.    

Permitting:                  By Seller at its expense.  

Construction:               By Seller at its expense; Seller owns the solar facilities.  

Ops. & Maint.:             By Seller.  Interconnection:          Seller will pay security payment, file and manage application with CL&P.  

Purchase of kWh:        Plymouth BoE buys 100% of the solar output from Seller (up to a maximum of 100% of total annual consumption).  

Purchase Price:            Plymouth BoE will purchase electricity at a starting price of $0.15/kWh, with annual price increases equal to the rate of inflation, as measured by the U.S. Consumer Price Index.  Annual increases will be at least 1.5% per year but will not exceed 3% in any one year.  Output Guaranty:         Seller guarantees annual output and will make a payment/credit to Plymouth BoE to cover any production shortfall.  Educational Program:   Seller will provide a custom, interactive educational program at no charge, for the benefit of Plymouth BoE students.  Operation Date:           On or before October 2014.  Purchase Option:         At the end of the 20-year PPA term, Plymouth BoE shall have the option to purchase the Systems at an amount equal to Fair Market Value (“FMV”), as defined by the Internal Revenue Code.  

Non-Purchase Rights:   Should Plymouth BoE elect not to purchase the Systems at the end of the 20-year term, then Seller shall have First Right of Offer to continue to sell electricity to Plymouth BoE at a price (including all ancillary costs of power such as transmission costs, demand charges and other typical utility charges) that is 25% less than the then current cost of power that Plymouth BoE could obtain from the lowest cost electricity provider available, to Plymouth BoE.  Seller will be entitled to lease the solar sites for the sum of  $1/year from Plymouth BoE.  Land Agreement for  132 Harwinton Ave:    The 8.5 acre site located at Map-Block-Lot 00096900, 132 Harwinton Avenue, hereinafter referred to as the “Adjoining Land”, will be purchased by Seller at its sole expense, for the construction of a solar system that will provide electricity to Terryville High School.  The Adjoining Land will be transferred from Seller to the Plymouth BoE at the end of the 20-year term, for the sum of $1.  Early Use of Land:       Plymouth BoE is entitled to define a portion of the 8.5 acres of Adjoining Land that Seller will lease to Plymouth BoE or Town of Plymouth for use during the 20-year PPA term. The Parties will agree upon an annual lease rate for the set-aside space.  

Billing:                         Seller will bill the Plymouth BoE every 30 days; Plymouth BoE has rights to audit records and to validate bills.  Virtual Net Metering:   Plymouth BoE and PhosEnergy will jointly identify opportunities (beneficial accounts as defined by CT Public Act 13-298 to utilize Virtual Net Metering (“VNM”) to reduce electricity bills for additional sites located in the Town of Plymouth that are not tied directly to a solar system.  Connection to Grid:     All connections will be behind Plymouth BoE’s existing meters.  

Rooftop Repairs:          Without charge, Plymouth BoE will have 3 days per calendar year to take the solar systems off-line to accomplish any roof maintenance or other repairs; more than 3 days, the Plymouth BoE bears the cost of lost kWh revenue to Seller.  

Snow Removal:            Plymouth BoE may remove snow from roof, while taking care to preserve safe operation of the solar panels.  Property Taxes:           Under CT law, solar systems are exempt from local property taxes.                 2.         Summary proposed site lease terms for the rooftop systems include:   SOLAR POWER SITE LEASE AGREEMENT: MAJOR TERMS  Party to Lease:            A special purpose entity (LLC) to be created and owned by Seller.  Lease term:                  20 years, running concurrently with the Power Purchase Agreement.  

Sites (Rooftops):  1.     Eli Terry Middle School;  2.     Harry S. Fisher Elementary School;  3.     Plymouth Center School.     Site Access:                  Subject to Plymouth BoE facility management requirements during and after construction for periodic maintenance.  Roof Rental:                $1.00 per year.  Ownership:                   Solar panels and related facilities (cabling, inverters, etc.) up to the CL&P connection are owned by Seller.  Maintenance:               Seller maintains solar systems.  Insurance:                    Seller provides insurance coverage for the systems.  Financing:                    First priority security interests granted to lenders.  Rooftops:                     Existing warranties protected; no rooftop penetrations in design and subject to Plymouth BoE approval.   3.         Plymouth BoE will provide reasonable assistance in support of Seller’s efforts to obtain required permits from all authorities having jurisdiction.  4.         PhosEnergy may assign its rights under the agreements in order to obtain financing and for other operating purposes as deemed appropriate.  The foregoing represents the understanding of the parties regarding the implementation of a solar  program by PhosEnergy LLC in accordance with Plymouth BoE, but does not purport to include all the essential terms of the program or to represent a legally binding agreement between the Parties.  A legally binding obligation, if any, shall only arise upon the execution of the definitive agreements for the Projects.  As such, the Parties hereto are executing this Memorandum to evidence their understanding of the components of the Program, and to evidence their intent to proceed to take the actions necessary to execute binding agreements and to participate in the Program by the due dates.  

PhosEnergy approached Plymouth Board of Education with a solar proposal in 2012, as a result of that effort, bids in the PURA ZREC auction were placed by PhosEnergy to secure subsidies at the highest possible bid in the auction in order to have a correspondingly lowest cost of electricity that would be purchased from solar electric arrays to be installed on the schools at no cost to the BoE. The economics of this balance between the competitiveness of last year’s ZREC bid, plus PhosEnergy’s price of electricity to the BoE had to add up to an attractive investment for a third party financial investor. Despite our bid last year comparing to the highest award by just over 1/10th of a penny per kWh, nevertheless we lost.  Presently:      Our goal however remained to bid in the 2013 auction and adjust up the price of electricity to the BoE from $0.12 to $0.15 and revise down our ZREC bid from  so that it would be more competitive.  We also needed to attract investment from the private sector to fund the construction of over $6M of solar electric projects. It is important to point out that there is no cost to the BoE to construct the solar electric projects at the four schools operated by Plymouth BoE. With Plymouth reliably paying for the solar electricity, and CL&P reliably paying for the ZRECs: For the Investor- that those two combined cash flows would amount to sufficient income over a 20 year power purchase agreement (and a fifteen year ZREC contract) to recover cost of construction of the solar projects. Additional Investor use of  the investment tax credit and depreciation to buy down cost by year five or six will lead to profitable income for the duration. For  the Board of Education- that 8.5 acres of land, adjoining the High School could be purchased by the company that owns the solar project and pay a mortgage on that land as part of a 20 year power purchase agreement with the BoE. At the end of the 20 year term, the investor will deed the land over to the Board of Education for $1.00, subject to terms. For the Town of Plymouth, that some percentage of that land would be available to the Town of Plymouth to build a new police station (subject to ground rent) and co-locate together with the newly constructed solar array on the same property where electricity for the high school was being generated. In addition to the purchase of more cost effective, clean, locally generated solar power, the proposal at hand offers to convey the entire 8.5 acre land parcel over to the BoE for the price of $1 subject to the following terms: The BoE may purchase the solar array in year 20 based upon it’s in-situ, market value (as defined by IRS) assuming continued operation over a minimum of a five year period. The BoE may choose not to purchase the solar array in year 20, but must offer to purchase electricity from the seller for a minimum of a five year period. The seller of the electricity must have first right of offer from the BoE to continue to sell electricity to the BoE at a price that is no greater than 25% less than the year 20 prevailing lowest cost of power from the grid. The BoE, as the new owner of the land will agree in advance to lease the solar area of land to the seller of electricity for $1/ Year.

Project Data

End-User: Plymouth Board of Education

Installer: Safari Energy

Location: Plymouth, Connecticut

Date of install: 5/ 2015

Size of system in kW: 260kW

Energy produced since installation: TBD

Special Challenges Met: Shading Analysis

Project Brief:

  This Memorandum of Understanding (“MoU”) is entered into by and between the Town of Plymouth, Connecticut Board of Education (“Plymouth BoE”), with offices at 77 Main Street, Terryville, Connecticut 06786, and PhosEnergy LLC (“PhosEnergy”), with offices located at 29 South Street, Manasquan, NJ 08736. Plymouth BoE and PhosEnergy are referred to collectively herein as the (“Parties”).                

WHEREAS, the Connecticut Light and Power Company (“CL&P”), pursuant to a Request for Proposals (“RFP”) in furtherance of the “Low and Zero Emissions Renewable Energy Credit Program” (the “Program”) established pursuant to Conn. Gen. Stat. § 16-244(r), 16-244(s) and 16-244(t), conducted a competitive bidding process in order to determine winning bidders based on lowest price and compliance with the terms and conditions of a fully executed Standard Contract for the Purchase and Sale of Connecticut Class I Renewable Energy Credits from Low and Zero Emission Projects (“the Projects”).  Based on bids submitted by PhosEnergy, CL&P has awarded PhosEnergy [_____] Standard Contracts for the Purchase and Sale of Connecticut Class I Renewable Energy Credits associated with Low and Zero Emission Projects that are being proposed for installation on or adjacent to four schools in the Town of Plymouth, specifically Terryville High School, Eli Terry Middle School, Harry S. Fisher Elementary School and Plymouth Center School; and                

WHEREAS, the Town of Plymouth, Connecticut held a Town Council Meeting on June 4, 2013 and voted unanimously to grant PhosEnergy status as Authorized Developer in order to permit PhosEnergy to submit bids into the Program, in response to the RFP; and     WHEREAS, Plymouth BoE and PhosEnergy desire to confirm the major terms under which the Projects will be designed, built, maintained and operated at the specified schools or sites; and    

WHEREAS, PhosEnergy has proposed to Plymouth BoE a competitive electricity pricing plan that will reduce Plymouth BoE’s price of electricity below current utility prices and will limit long term future electricity price increases; and    

WHEREAS, the Program requires certain timely responses from PhosEnergy during the Month of August 2013, in order to confirm the award of the Contracts, pursuant to the RFP.     Now, therefore, time being of the essence, and in consideration of the foregoing recitals, Plymouth BoE and PhosEnergy have entered into this MOU in order to advance their respective interests, and hereby agree as follows:     1.              The Parties will commence power purchase agreement (“PPA”) and site lease negotiations in good faith and as follows:  within five (5) business days after the execution of this MoU, PhosEnergy shall provide to Plymouth BoE a proposed PPA and lease agreement, incorporating the following major terms:  SOLAR POWER PURCHASE AGREEMENT  MAJOR TERMS  PPA Parties:                

PhosEnergy LLC or “Seller”, as defined in the PPA; Plymouth BoE or “Host Customer” as defined in the PPA.  

Term:                          20 years.  

Sites/Solar Systems:       1.     Terryville High School;  2.     Eli Terry Middle School;  3.     Harry S. Fisher Elementary School;  4.     Plymouth Center School.    

Permitting:                  By Seller at its expense.  

Construction:               By Seller at its expense; Seller owns the solar facilities.  

Ops. & Maint.:             By Seller.  Interconnection:          Seller will pay security payment, file and manage application with CL&P.  

Purchase of kWh:        Plymouth BoE buys 100% of the solar output from Seller (up to a maximum of 100% of total annual consumption).  

Purchase Price:            Plymouth BoE will purchase electricity at a starting price of $0.15/kWh, with annual price increases equal to the rate of inflation, as measured by the U.S. Consumer Price Index.  Annual increases will be at least 1.5% per year but will not exceed 3% in any one year.  Output Guaranty:         Seller guarantees annual output and will make a payment/credit to Plymouth BoE to cover any production shortfall.  Educational Program:   Seller will provide a custom, interactive educational program at no charge, for the benefit of Plymouth BoE students.  Operation Date:           On or before October 2014.  Purchase Option:         At the end of the 20-year PPA term, Plymouth BoE shall have the option to purchase the Systems at an amount equal to Fair Market Value (“FMV”), as defined by the Internal Revenue Code.  

Non-Purchase Rights:   Should Plymouth BoE elect not to purchase the Systems at the end of the 20-year term, then Seller shall have First Right of Offer to continue to sell electricity to Plymouth BoE at a price (including all ancillary costs of power such as transmission costs, demand charges and other typical utility charges) that is 25% less than the then current cost of power that Plymouth BoE could obtain from the lowest cost electricity provider available, to Plymouth BoE.  Seller will be entitled to lease the solar sites for the sum of  $1/year from Plymouth BoE.  Land Agreement for  132 Harwinton Ave:    The 8.5 acre site located at Map-Block-Lot 00096900, 132 Harwinton Avenue, hereinafter referred to as the “Adjoining Land”, will be purchased by Seller at its sole expense, for the construction of a solar system that will provide electricity to Terryville High School.  The Adjoining Land will be transferred from Seller to the Plymouth BoE at the end of the 20-year term, for the sum of $1.  Early Use of Land:       Plymouth BoE is entitled to define a portion of the 8.5 acres of Adjoining Land that Seller will lease to Plymouth BoE or Town of Plymouth for use during the 20-year PPA term. The Parties will agree upon an annual lease rate for the set-aside space.  

Billing:                         Seller will bill the Plymouth BoE every 30 days; Plymouth BoE has rights to audit records and to validate bills.  Virtual Net Metering:   Plymouth BoE and PhosEnergy will jointly identify opportunities (beneficial accounts as defined by CT Public Act 13-298 to utilize Virtual Net Metering (“VNM”) to reduce electricity bills for additional sites located in the Town of Plymouth that are not tied directly to a solar system.  Connection to Grid:     All connections will be behind Plymouth BoE’s existing meters.  

Rooftop Repairs:          Without charge, Plymouth BoE will have 3 days per calendar year to take the solar systems off-line to accomplish any roof maintenance or other repairs; more than 3 days, the Plymouth BoE bears the cost of lost kWh revenue to Seller.  

Snow Removal:            Plymouth BoE may remove snow from roof, while taking care to preserve safe operation of the solar panels.  Property Taxes:           Under CT law, solar systems are exempt from local property taxes.                 2.         Summary proposed site lease terms for the rooftop systems include:   SOLAR POWER SITE LEASE AGREEMENT: MAJOR TERMS  Party to Lease:            A special purpose entity (LLC) to be created and owned by Seller.  Lease term:                  20 years, running concurrently with the Power Purchase Agreement.  

Sites (Rooftops):  1.     Eli Terry Middle School;  2.     Harry S. Fisher Elementary School;  3.     Plymouth Center School.     Site Access:                  Subject to Plymouth BoE facility management requirements during and after construction for periodic maintenance.  Roof Rental:                $1.00 per year.  Ownership:                   Solar panels and related facilities (cabling, inverters, etc.) up to the CL&P connection are owned by Seller.  Maintenance:               Seller maintains solar systems.  Insurance:                    Seller provides insurance coverage for the systems.  Financing:                    First priority security interests granted to lenders.  Rooftops:                     Existing warranties protected; no rooftop penetrations in design and subject to Plymouth BoE approval.   3.         Plymouth BoE will provide reasonable assistance in support of Seller’s efforts to obtain required permits from all authorities having jurisdiction.  4.         PhosEnergy may assign its rights under the agreements in order to obtain financing and for other operating purposes as deemed appropriate.  The foregoing represents the understanding of the parties regarding the implementation of a solar  program by PhosEnergy LLC in accordance with Plymouth BoE, but does not purport to include all the essential terms of the program or to represent a legally binding agreement between the Parties.  A legally binding obligation, if any, shall only arise upon the execution of the definitive agreements for the Projects.  As such, the Parties hereto are executing this Memorandum to evidence their understanding of the components of the Program, and to evidence their intent to proceed to take the actions necessary to execute binding agreements and to participate in the Program by the due dates.  

PhosEnergy approached Plymouth Board of Education with a solar proposal in 2012, as a result of that effort, bids in the PURA ZREC auction were placed by PhosEnergy to secure subsidies at the highest possible bid in the auction in order to have a correspondingly lowest cost of electricity that would be purchased from solar electric arrays to be installed on the schools at no cost to the BoE. The economics of this balance between the competitiveness of last year’s ZREC bid, plus PhosEnergy’s price of electricity to the BoE had to add up to an attractive investment for a third party financial investor. Despite our bid last year comparing to the highest award by just over 1/10th of a penny per kWh, nevertheless we lost.  Presently:      Our goal however remained to bid in the 2013 auction and adjust up the price of electricity to the BoE from $0.12 to $0.15 and revise down our ZREC bid from  so that it would be more competitive.  We also needed to attract investment from the private sector to fund the construction of over $6M of solar electric projects. It is important to point out that there is no cost to the BoE to construct the solar electric projects at the four schools operated by Plymouth BoE. With Plymouth reliably paying for the solar electricity, and CL&P reliably paying for the ZRECs: For the Investor- that those two combined cash flows would amount to sufficient income over a 20 year power purchase agreement (and a fifteen year ZREC contract) to recover cost of construction of the solar projects. Additional Investor use of  the investment tax credit and depreciation to buy down cost by year five or six will lead to profitable income for the duration. For  the Board of Education- that 8.5 acres of land, adjoining the High School could be purchased by the company that owns the solar project and pay a mortgage on that land as part of a 20 year power purchase agreement with the BoE. At the end of the 20 year term, the investor will deed the land over to the Board of Education for $1.00, subject to terms. For the Town of Plymouth, that some percentage of that land would be available to the Town of Plymouth to build a new police station (subject to ground rent) and co-locate together with the newly constructed solar array on the same property where electricity for the high school was being generated. In addition to the purchase of more cost effective, clean, locally generated solar power, the proposal at hand offers to convey the entire 8.5 acre land parcel over to the BoE for the price of $1 subject to the following terms: The BoE may purchase the solar array in year 20 based upon it’s in-situ, market value (as defined by IRS) assuming continued operation over a minimum of a five year period. The BoE may choose not to purchase the solar array in year 20, but must offer to purchase electricity from the seller for a minimum of a five year period. The seller of the electricity must have first right of offer from the BoE to continue to sell electricity to the BoE at a price that is no greater than 25% less than the year 20 prevailing lowest cost of power from the grid. The BoE, as the new owner of the land will agree in advance to lease the solar area of land to the seller of electricity for $1/ Year.

Project Data

End-User: Plymouth Board of Education

Installer: Safari Energy

Location: Plymouth, Connecticut

Date of install: 5/ 2015

Size of system in kW: 230kW

Energy produced since installation: TBD

Special Challenges Met: Shading Analysis

Project Brief:

  This Memorandum of Understanding (“MoU”) is entered into by and between the Town of Plymouth, Connecticut Board of Education (“Plymouth BoE”), with offices at 77 Main Street, Terryville, Connecticut 06786, and PhosEnergy LLC (“PhosEnergy”), with offices located at 29 South Street, Manasquan, NJ 08736. Plymouth BoE and PhosEnergy are referred to collectively herein as the (“Parties”).                

WHEREAS, the Connecticut Light and Power Company (“CL&P”), pursuant to a Request for Proposals (“RFP”) in furtherance of the “Low and Zero Emissions Renewable Energy Credit Program” (the “Program”) established pursuant to Conn. Gen. Stat. § 16-244(r), 16-244(s) and 16-244(t), conducted a competitive bidding process in order to determine winning bidders based on lowest price and compliance with the terms and conditions of a fully executed Standard Contract for the Purchase and Sale of Connecticut Class I Renewable Energy Credits from Low and Zero Emission Projects (“the Projects”).  Based on bids submitted by PhosEnergy, CL&P has awarded PhosEnergy [_____] Standard Contracts for the Purchase and Sale of Connecticut Class I Renewable Energy Credits associated with Low and Zero Emission Projects that are being proposed for installation on or adjacent to four schools in the Town of Plymouth, specifically Terryville High School, Eli Terry Middle School, Harry S. Fisher Elementary School and Plymouth Center School; and                

WHEREAS, the Town of Plymouth, Connecticut held a Town Council Meeting on June 4, 2013 and voted unanimously to grant PhosEnergy status as Authorized Developer in order to permit PhosEnergy to submit bids into the Program, in response to the RFP; and     WHEREAS, Plymouth BoE and PhosEnergy desire to confirm the major terms under which the Projects will be designed, built, maintained and operated at the specified schools or sites; and    

WHEREAS, PhosEnergy has proposed to Plymouth BoE a competitive electricity pricing plan that will reduce Plymouth BoE’s price of electricity below current utility prices and will limit long term future electricity price increases; and    

WHEREAS, the Program requires certain timely responses from PhosEnergy during the Month of August 2013, in order to confirm the award of the Contracts, pursuant to the RFP.     Now, therefore, time being of the essence, and in consideration of the foregoing recitals, Plymouth BoE and PhosEnergy have entered into this MOU in order to advance their respective interests, and hereby agree as follows:     1.              The Parties will commence power purchase agreement (“PPA”) and site lease negotiations in good faith and as follows:  within five (5) business days after the execution of this MoU, PhosEnergy shall provide to Plymouth BoE a proposed PPA and lease agreement, incorporating the following major terms:  SOLAR POWER PURCHASE AGREEMENT  MAJOR TERMS  PPA Parties:                

PhosEnergy LLC or “Seller”, as defined in the PPA; Plymouth BoE or “Host Customer” as defined in the PPA.  

Term:                          20 years.  

Sites/Solar Systems:       1.     Terryville High School;  2.     Eli Terry Middle School;  3.     Harry S. Fisher Elementary School;  4.     Plymouth Center School.    

Permitting:                  By Seller at its expense.  

Construction:               By Seller at its expense; Seller owns the solar facilities.  

Ops. & Maint.:             By Seller.  Interconnection:          Seller will pay security payment, file and manage application with CL&P.  

Purchase of kWh:        Plymouth BoE buys 100% of the solar output from Seller (up to a maximum of 100% of total annual consumption).  

Purchase Price:            Plymouth BoE will purchase electricity at a starting price of $0.15/kWh, with annual price increases equal to the rate of inflation, as measured by the U.S. Consumer Price Index.  Annual increases will be at least 1.5% per year but will not exceed 3% in any one year.  Output Guaranty:         Seller guarantees annual output and will make a payment/credit to Plymouth BoE to cover any production shortfall.  Educational Program:   Seller will provide a custom, interactive educational program at no charge, for the benefit of Plymouth BoE students.  Operation Date:           On or before October 2014.  Purchase Option:         At the end of the 20-year PPA term, Plymouth BoE shall have the option to purchase the Systems at an amount equal to Fair Market Value (“FMV”), as defined by the Internal Revenue Code.  

Non-Purchase Rights:   Should Plymouth BoE elect not to purchase the Systems at the end of the 20-year term, then Seller shall have First Right of Offer to continue to sell electricity to Plymouth BoE at a price (including all ancillary costs of power such as transmission costs, demand charges and other typical utility charges) that is 25% less than the then current cost of power that Plymouth BoE could obtain from the lowest cost electricity provider available, to Plymouth BoE.  Seller will be entitled to lease the solar sites for the sum of  $1/year from Plymouth BoE.  Land Agreement for  132 Harwinton Ave:    The 8.5 acre site located at Map-Block-Lot 00096900, 132 Harwinton Avenue, hereinafter referred to as the “Adjoining Land”, will be purchased by Seller at its sole expense, for the construction of a solar system that will provide electricity to Terryville High School.  The Adjoining Land will be transferred from Seller to the Plymouth BoE at the end of the 20-year term, for the sum of $1.  Early Use of Land:       Plymouth BoE is entitled to define a portion of the 8.5 acres of Adjoining Land that Seller will lease to Plymouth BoE or Town of Plymouth for use during the 20-year PPA term. The Parties will agree upon an annual lease rate for the set-aside space.  

Billing:                         Seller will bill the Plymouth BoE every 30 days; Plymouth BoE has rights to audit records and to validate bills.  Virtual Net Metering:   Plymouth BoE and PhosEnergy will jointly identify opportunities (beneficial accounts as defined by CT Public Act 13-298 to utilize Virtual Net Metering (“VNM”) to reduce electricity bills for additional sites located in the Town of Plymouth that are not tied directly to a solar system.  Connection to Grid:     All connections will be behind Plymouth BoE’s existing meters.  

Rooftop Repairs:          Without charge, Plymouth BoE will have 3 days per calendar year to take the solar systems off-line to accomplish any roof maintenance or other repairs; more than 3 days, the Plymouth BoE bears the cost of lost kWh revenue to Seller.  

Snow Removal:            Plymouth BoE may remove snow from roof, while taking care to preserve safe operation of the solar panels.  Property Taxes:           Under CT law, solar systems are exempt from local property taxes.                 2.         Summary proposed site lease terms for the rooftop systems include:   SOLAR POWER SITE LEASE AGREEMENT: MAJOR TERMS  Party to Lease:            A special purpose entity (LLC) to be created and owned by Seller.  Lease term:                  20 years, running concurrently with the Power Purchase Agreement.  

Sites (Rooftops):  1.     Eli Terry Middle School;  2.     Harry S. Fisher Elementary School;  3.     Plymouth Center School.     Site Access:                  Subject to Plymouth BoE facility management requirements during and after construction for periodic maintenance.  Roof Rental:                $1.00 per year.  Ownership:                   Solar panels and related facilities (cabling, inverters, etc.) up to the CL&P connection are owned by Seller.  Maintenance:               Seller maintains solar systems.  Insurance:                    Seller provides insurance coverage for the systems.  Financing:                    First priority security interests granted to lenders.  Rooftops:                     Existing warranties protected; no rooftop penetrations in design and subject to Plymouth BoE approval.   3.         Plymouth BoE will provide reasonable assistance in support of Seller’s efforts to obtain required permits from all authorities having jurisdiction.  4.         PhosEnergy may assign its rights under the agreements in order to obtain financing and for other operating purposes as deemed appropriate.  The foregoing represents the understanding of the parties regarding the implementation of a solar  program by PhosEnergy LLC in accordance with Plymouth BoE, but does not purport to include all the essential terms of the program or to represent a legally binding agreement between the Parties.  A legally binding obligation, if any, shall only arise upon the execution of the definitive agreements for the Projects.  As such, the Parties hereto are executing this Memorandum to evidence their understanding of the components of the Program, and to evidence their intent to proceed to take the actions necessary to execute binding agreements and to participate in the Program by the due dates.  

PhosEnergy approached Plymouth Board of Education with a solar proposal in 2012, as a result of that effort, bids in the PURA ZREC auction were placed by PhosEnergy to secure subsidies at the highest possible bid in the auction in order to have a correspondingly lowest cost of electricity that would be purchased from solar electric arrays to be installed on the schools at no cost to the BoE. The economics of this balance between the competitiveness of last year’s ZREC bid, plus PhosEnergy’s price of electricity to the BoE had to add up to an attractive investment for a third party financial investor. Despite our bid last year comparing to the highest award by just over 1/10th of a penny per kWh, nevertheless we lost.  Presently:      Our goal however remained to bid in the 2013 auction and adjust up the price of electricity to the BoE from $0.12 to $0.15 and revise down our ZREC bid from  so that it would be more competitive.  We also needed to attract investment from the private sector to fund the construction of over $6M of solar electric projects. It is important to point out that there is no cost to the BoE to construct the solar electric projects at the four schools operated by Plymouth BoE. With Plymouth reliably paying for the solar electricity, and CL&P reliably paying for the ZRECs: For the Investor- that those two combined cash flows would amount to sufficient income over a 20 year power purchase agreement (and a fifteen year ZREC contract) to recover cost of construction of the solar projects. Additional Investor use of  the investment tax credit and depreciation to buy down cost by year five or six will lead to profitable income for the duration. For  the Board of Education- that 8.5 acres of land, adjoining the High School could be purchased by the company that owns the solar project and pay a mortgage on that land as part of a 20 year power purchase agreement with the BoE. At the end of the 20 year term, the investor will deed the land over to the Board of Education for $1.00, subject to terms. For the Town of Plymouth, that some percentage of that land would be available to the Town of Plymouth to build a new police station (subject to ground rent) and co-locate together with the newly constructed solar array on the same property where electricity for the high school was being generated. In addition to the purchase of more cost effective, clean, locally generated solar power, the proposal at hand offers to convey the entire 8.5 acre land parcel over to the BoE for the price of $1 subject to the following terms: The BoE may purchase the solar array in year 20 based upon it’s in-situ, market value (as defined by IRS) assuming continued operation over a minimum of a five year period. The BoE may choose not to purchase the solar array in year 20, but must offer to purchase electricity from the seller for a minimum of a five year period. The seller of the electricity must have first right of offer from the BoE to continue to sell electricity to the BoE at a price that is no greater than 25% less than the year 20 prevailing lowest cost of power from the grid. The BoE, as the new owner of the land will agree in advance to lease the solar area of land to the seller of electricity for $1/ Year.

Project Data

End-User: Plymouth Board of Education

Installer: Safari Energy

Location: Plymouth, Connecticut

Date of install: 5/ 2015

Size of system in kW: 700kW- 1400kW

Energy produced since installation: TBD

Special Challenges Met: Shading Analysis

Project Brief:

  This Memorandum of Understanding (“MoU”) is entered into by and between the Town of Plymouth, Connecticut Board of Education (“Plymouth BoE”), with offices at 77 Main Street, Terryville, Connecticut 06786, and PhosEnergy LLC (“PhosEnergy”), with offices located at 29 South Street, Manasquan, NJ 08736. Plymouth BoE and PhosEnergy are referred to collectively herein as the (“Parties”).                

WHEREAS, the Connecticut Light and Power Company (“CL&P”), pursuant to a Request for Proposals (“RFP”) in furtherance of the “Low and Zero Emissions Renewable Energy Credit Program” (the “Program”) established pursuant to Conn. Gen. Stat. § 16-244(r), 16-244(s) and 16-244(t), conducted a competitive bidding process in order to determine winning bidders based on lowest price and compliance with the terms and conditions of a fully executed Standard Contract for the Purchase and Sale of Connecticut Class I Renewable Energy Credits from Low and Zero Emission Projects (“the Projects”).  Based on bids submitted by PhosEnergy, CL&P has awarded PhosEnergy [_____] Standard Contracts for the Purchase and Sale of Connecticut Class I Renewable Energy Credits associated with Low and Zero Emission Projects that are being proposed for installation on or adjacent to four schools in the Town of Plymouth, specifically Terryville High School, Eli Terry Middle School, Harry S. Fisher Elementary School and Plymouth Center School; and                

WHEREAS, the Town of Plymouth, Connecticut held a Town Council Meeting on June 4, 2013 and voted unanimously to grant PhosEnergy status as Authorized Developer in order to permit PhosEnergy to submit bids into the Program, in response to the RFP; and     WHEREAS, Plymouth BoE and PhosEnergy desire to confirm the major terms under which the Projects will be designed, built, maintained and operated at the specified schools or sites; and    

WHEREAS, PhosEnergy has proposed to Plymouth BoE a competitive electricity pricing plan that will reduce Plymouth BoE’s price of electricity below current utility prices and will limit long term future electricity price increases; and    

WHEREAS, the Program requires certain timely responses from PhosEnergy during the Month of August 2013, in order to confirm the award of the Contracts, pursuant to the RFP.     Now, therefore, time being of the essence, and in consideration of the foregoing recitals, Plymouth BoE and PhosEnergy have entered into this MOU in order to advance their respective interests, and hereby agree as follows:     1.              The Parties will commence power purchase agreement (“PPA”) and site lease negotiations in good faith and as follows:  within five (5) business days after the execution of this MoU, PhosEnergy shall provide to Plymouth BoE a proposed PPA and lease agreement, incorporating the following major terms:  SOLAR POWER PURCHASE AGREEMENT  MAJOR TERMS  PPA Parties:                

PhosEnergy LLC or “Seller”, as defined in the PPA; Plymouth BoE or “Host Customer” as defined in the PPA.  

Term:                          20 years.  

Sites/Solar Systems:       1.     Terryville High School;  2.     Eli Terry Middle School;  3.     Harry S. Fisher Elementary School;  4.     Plymouth Center School.    

Permitting:                  By Seller at its expense.  

Construction:               By Seller at its expense; Seller owns the solar facilities.  

Ops. & Maint.:             By Seller.  Interconnection:          Seller will pay security payment, file and manage application with CL&P.  

Purchase of kWh:        Plymouth BoE buys 100% of the solar output from Seller (up to a maximum of 100% of total annual consumption).  

Purchase Price:            Plymouth BoE will purchase electricity at a starting price of $0.15/kWh, with annual price increases equal to the rate of inflation, as measured by the U.S. Consumer Price Index.  Annual increases will be at least 1.5% per year but will not exceed 3% in any one year.  Output Guaranty:         Seller guarantees annual output and will make a payment/credit to Plymouth BoE to cover any production shortfall.  Educational Program:   Seller will provide a custom, interactive educational program at no charge, for the benefit of Plymouth BoE students.  Operation Date:           On or before October 2014.  Purchase Option:         At the end of the 20-year PPA term, Plymouth BoE shall have the option to purchase the Systems at an amount equal to Fair Market Value (“FMV”), as defined by the Internal Revenue Code.  

Non-Purchase Rights:   Should Plymouth BoE elect not to purchase the Systems at the end of the 20-year term, then Seller shall have First Right of Offer to continue to sell electricity to Plymouth BoE at a price (including all ancillary costs of power such as transmission costs, demand charges and other typical utility charges) that is 25% less than the then current cost of power that Plymouth BoE could obtain from the lowest cost electricity provider available, to Plymouth BoE.  Seller will be entitled to lease the solar sites for the sum of  $1/year from Plymouth BoE.  Land Agreement for  132 Harwinton Ave:    The 8.5 acre site located at Map-Block-Lot 00096900, 132 Harwinton Avenue, hereinafter referred to as the “Adjoining Land”, will be purchased by Seller at its sole expense, for the construction of a solar system that will provide electricity to Terryville High School.  The Adjoining Land will be transferred from Seller to the Plymouth BoE at the end of the 20-year term, for the sum of $1.  Early Use of Land:       Plymouth BoE is entitled to define a portion of the 8.5 acres of Adjoining Land that Seller will lease to Plymouth BoE or Town of Plymouth for use during the 20-year PPA term. The Parties will agree upon an annual lease rate for the set-aside space.  

Billing:                         Seller will bill the Plymouth BoE every 30 days; Plymouth BoE has rights to audit records and to validate bills.  Virtual Net Metering:   Plymouth BoE and PhosEnergy will jointly identify opportunities (beneficial accounts as defined by CT Public Act 13-298 to utilize Virtual Net Metering (“VNM”) to reduce electricity bills for additional sites located in the Town of Plymouth that are not tied directly to a solar system.  Connection to Grid:     All connections will be behind Plymouth BoE’s existing meters.  

Rooftop Repairs:          Without charge, Plymouth BoE will have 3 days per calendar year to take the solar systems off-line to accomplish any roof maintenance or other repairs; more than 3 days, the Plymouth BoE bears the cost of lost kWh revenue to Seller.  

Snow Removal:            Plymouth BoE may remove snow from roof, while taking care to preserve safe operation of the solar panels.  Property Taxes:           Under CT law, solar systems are exempt from local property taxes.                 2.         Summary proposed site lease terms for the rooftop systems include:   SOLAR POWER SITE LEASE AGREEMENT: MAJOR TERMS  Party to Lease:            A special purpose entity (LLC) to be created and owned by Seller.  Lease term:                  20 years, running concurrently with the Power Purchase Agreement.  

Sites (Rooftops):  1.     Eli Terry Middle School;  2.     Harry S. Fisher Elementary School;  3.     Plymouth Center School.     Site Access:                  Subject to Plymouth BoE facility management requirements during and after construction for periodic maintenance.  Roof Rental:                $1.00 per year.  Ownership:                   Solar panels and related facilities (cabling, inverters, etc.) up to the CL&P connection are owned by Seller.  Maintenance:               Seller maintains solar systems.  Insurance:                    Seller provides insurance coverage for the systems.  Financing:                    First priority security interests granted to lenders.  Rooftops:                     Existing warranties protected; no rooftop penetrations in design and subject to Plymouth BoE approval.   3.         Plymouth BoE will provide reasonable assistance in support of Seller’s efforts to obtain required permits from all authorities having jurisdiction.  4.         PhosEnergy may assign its rights under the agreements in order to obtain financing and for other operating purposes as deemed appropriate.  The foregoing represents the understanding of the parties regarding the implementation of a solar  program by PhosEnergy LLC in accordance with Plymouth BoE, but does not purport to include all the essential terms of the program or to represent a legally binding agreement between the Parties.  A legally binding obligation, if any, shall only arise upon the execution of the definitive agreements for the Projects.  As such, the Parties hereto are executing this Memorandum to evidence their understanding of the components of the Program, and to evidence their intent to proceed to take the actions necessary to execute binding agreements and to participate in the Program by the due dates.  

PhosEnergy approached Plymouth Board of Education with a solar proposal in 2012, as a result of that effort, bids in the PURA ZREC auction were placed by PhosEnergy to secure subsidies at the highest possible bid in the auction in order to have a correspondingly lowest cost of electricity that would be purchased from solar electric arrays to be installed on the schools at no cost to the BoE. The economics of this balance between the competitiveness of last year’s ZREC bid, plus PhosEnergy’s price of electricity to the BoE had to add up to an attractive investment for a third party financial investor. Despite our bid last year comparing to the highest award by just over 1/10th of a penny per kWh, nevertheless we lost.  Presently:      Our goal however remained to bid in the 2013 auction and adjust up the price of electricity to the BoE from $0.12 to $0.15 and revise down our ZREC bid from  so that it would be more competitive.  We also needed to attract investment from the private sector to fund the construction of over $6M of solar electric projects. It is important to point out that there is no cost to the BoE to construct the solar electric projects at the four schools operated by Plymouth BoE. With Plymouth reliably paying for the solar electricity, and CL&P reliably paying for the ZRECs: For the Investor- that those two combined cash flows would amount to sufficient income over a 20 year power purchase agreement (and a fifteen year ZREC contract) to recover cost of construction of the solar projects. Additional Investor use of  the investment tax credit and depreciation to buy down cost by year five or six will lead to profitable income for the duration. For  the Board of Education- that 8.5 acres of land, adjoining the High School could be purchased by the company that owns the solar project and pay a mortgage on that land as part of a 20 year power purchase agreement with the BoE. At the end of the 20 year term, the investor will deed the land over to the Board of Education for $1.00, subject to terms. For the Town of Plymouth, that some percentage of that land would be available to the Town of Plymouth to build a new police station (subject to ground rent) and co-locate together with the newly constructed solar array on the same property where electricity for the high school was being generated. In addition to the purchase of more cost effective, clean, locally generated solar power, the proposal at hand offers to convey the entire 8.5 acre land parcel over to the BoE for the price of $1 subject to the following terms: The BoE may purchase the solar array in year 20 based upon it’s in-situ, market value (as defined by IRS) assuming continued operation over a minimum of a five year period. The BoE may choose not to purchase the solar array in year 20, but must offer to purchase electricity from the seller for a minimum of a five year period. The seller of the electricity must have first right of offer from the BoE to continue to sell electricity to the BoE at a price that is no greater than 25% less than the year 20 prevailing lowest cost of power from the grid. The BoE, as the new owner of the land will agree in advance to lease the solar area of land to the seller of electricity for $1/ Year.