“In the day”, I was sent to Siemens Photovoltaic Cell manufacturing plant in Santa Barbara to visit with the Southern California Edison customer, document the manufacturing process and take some pictures for my bosses presentation. It has been years since then and the United States, the once leader in cell manufacturing, has given way to others overseas (~four(4) cell manufacturers remain in U.S.). As a result, a manufacturing goal of 100% “Made in the United States” cannot be achieved for photovoltaic (PV) modules with mono-crystalline cells at cost effective prices. Never the less, other quantifiable goals like USGBC LEED Material Resource Credits can be achieved.
Various products can claim to be as much as 80% made in the United States and anywhere from $1.80 to $4.50/Watt installed (including but not limited to, additional structural systems like; racking, ballast, lagging or wood lattice). Using a goal to be the “Greenest” possible without additional expense, the owners of EcoGym Worldwide set out to design a PV System that met some of these goals. Seeking the guidance of A Solar Studio, a small 2-3 man studio in Naperville who’s principal has been involved with PV off and on for the past twenty years, they learned they could achieve some of these goals using the Solon Sol quick 295.
Ecogym’s solar renewable system was designed for a flat roof commercial tenant space approximately 10,000 square feet, few obstructions in the roof, 5 air handling units and a 4′-6″ south facing parapet. The system is is expected to produce 7.93 kW of AC power each solar hour per day and has been designed for a future second phase development if needed. Yellowlite, Inc., a regional solar installer located in Cleveland, Ohio was selected as general contractor and installer. Solon Corporation is a subsidiary of Solon Group located in Tucson, AZ provided the modules for the system.
The Solon Solquick 295 module is largely manufactured in the United States. The critical monolithic rack (perhaps 60% by weight) is made in Minnesota where it is then shipped to Arizona for assembly and testing prior to shipment. They are a fixed tilt (~9°), ballasted, non framed rack. The 295W modules are connected in series and provide designers with a low profile tilt thereby reducing wind loads significantly and with no snow drift issues caused by the array. In addition to the interconnection ties and cinder blocks used for ballasting, the A Solar Studio design team required an additional 5 positive connections on both the east and west sides of the arrays. These connections are lagged through the roof reducing uplift most prominent in the winter months of northern Illinois.
Assembled in Arizona, Solon uses a Fibrex® monolithic rack (an Andersen Corporation product) on which, a Solon poly-crystalline PV panel is mounted. The pre-assembled module reduces the amount of work that needs to be done on site. Installers set the modules on the roof, link them together with plastic connectors and plug wires together to establish base electrical connections (modules have no exposed metal therefore no grounding is required). Product design clearly reduced the time needed for mechanically mounting the panels by approximately 65% even though weather was an issue. The time needed for making the electrical connections was reduced by half. Two (2) SMA Sunny Boy 6000W inverters were installed along with the SMA WebBox.
The net metering process was very simple by comparison to other utilities in the northern Illinois area. The City of Naperville has its own municipal utility where it gets a large portion of its electricity from renewable resources west of the community in the form of wind turbines. Its net metering process consists of a one (1) sheet application submitted at the time of permitting with no other communication exchanges needed unless a copy of the application is not available on-site when final inspection is conducted.
As we all know, the USGBC LEED building performance documentation tool is the benchmark rating system for all “Green” buildings. Within the rating system, we look at and credit projects that use recycled or reclaimed building material such as wood, brick, glass, steel and so on. Again, recycled material is waste that has been turned into a new product. Reused, reclaimed, or salvaged, material is “waste” that is saved used again in its original form. In addition, we look at pre and post consumer waste and post industrial waste when documenting building product and systems in a particular project. Therefore, when seeking renewable credits through the LEED Certification process, the design team should look to american.
Photovoltaic Cell Manufacturers
At the time of this article, the Photovoltaic market segment although fairly stable has been going through staggered growth largely do to the lack of cell manufacturing in the United States. This analyst argues that more cell manufacturing should be provided within the US market. One such business paradigm may be a fully integrated vertical model in which a manufacturer not only produces modules but also cells. Currently, only four (4) photovoltaic cell manufacturers are located in continental U.S.: Solar World; Suniva; Solar Power Industries (SPI) and Silicor Materials (Calisolar). As a result, cell manufacturing will dictate cost prohibitions at the module manufacturing process which may dictate photovoltaic cell cost and/or purchasing in turn, affect system material rating in USGBC’s LEED building performance rating but should not impact specification requirements in Section 13650, Part 2, 2.02 Photovoltaic System, F- Typical Electrical Characteristics.
Unitary Mount (mounting System)
Fibrex® is manufactured by Andersen. It is a composite that combines 40 % wood fiber reclaimed from Andersen’s manufacturing processes (pre-consumer reclaimed wood fiber by weight) with 60 % thermoplastic polymer (partially reclaimed). The Fibrex® composite rack is also post consumer reclaimable. SOLONs module benefits exceed solar power production goals by including high durability, stiffness, moisture and heat resistance, non-conductivity, and thermal insulating properties. These characteristics help ensure that the Solon Solquick does not require grounding, while reducing heating and cooling requirements. An added benefit is that the material is extremely lightweight, making it an attractive option for PV racking materials. Manufacturing Location – Bayport, MN