Top Quality Solar Power Crystalline Modules Are All About The Same *
Solar power modules are composed of multiple solar cells, along with the necessary internal wiring, aluminum and glass framework, and external electrical connections. Modules range in power from about 50 watts up to 220 watts (any bigger than this and the modules become difficult to handle by one person). Although modules are usually installed on top of a roof or on an external structure, new designs include the solar electric cells as part of traditional building materials -- such as shingles and rolled out roofing. The array shown in the photo above is composed of 36 individual 165 watt PV modules.
Solar energy modules from Kyocera, Sharp, SunPower, and PowerLight shown below all have 25+ year lifetimes, lightweight roof loading and comparable power outputs per dollar. Additional costs for the higher efficiency modules offered by most manufacturers are a good tradeoff when available unshaded roof space is limited. In our experience, solar power modules from the established manufacturers are a reliable and sound investment when properly installed and sized to your building's power needs.
Sharp Solar Power Module
SunPower Solar Power Module
Kyocera Solar Power Module
PowerGuard Solar Power Module
Building Integrated Photovoltaics (BIPV) Several companies offer solar energy cells that have been integrated with traditional shingles. Theoretically, these can be a good choice for new construction and major renovations since they slightly offset costs for other building materials -- although they are still more expensive than traditional panels. They are quite appealing from an architectural standpoint, and are usually most compatible with slate or masonry roofs. However, careful consideration must be paid to roof loading, solar electric shingle interconnection reliability (typically below the shingles) and output degradation due to high temperature operation.
264 UniSolar 128 watt roof modules installed by Akeena Solar on the new Brentwood Empire school.
UniSolar Solar Laminate
Solar power cells can also be integrated with metal seam roofing, either as part of pre-fabricated panels or field-applied rolled out adhesive cell material. Interconnections among modules and other system components are usually done at the peak of the roof or under the eaves. Solar energy modules that are integrated with skylites and window walls are also available. However, because of the high DC voltages in solar modules, these Building Integrated Photovoltaic (BIPV) systems have to be designed carefully to prevent shock hazards and to preserve the integrity of the building shell.
* Monocrystalline and polycrystalline solar power modules from Kyocera, Sharp, SunPower, Sanyo, Shell and BP Solar are all pretty much the same. The most important considerations are warranty periods, manufacturer responsiveness and total installed cost per watt to the customer. Take it with a grain of salt if a salesman tells you that one particular company's product is clearly superior to those of the others.