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| Solar Photovoltaic Electricity "solar panels" Around for many years now, the basics of PV (photovoltaic) technology are known to most. Simply put its the capture and transformation of solar energy into usable energy. Recent advances in PV technology, lead to the creation of a more efficient fourth generation of PV cells. Most PV cells are either single crystal or multicrystalline. Comparable in most ways, multicrystalline cells prove to be more affordable initially, while single crystal cells are more efficient but hold a higher initial cost. With an average weight of 5psf (pounds per square foot), structural improvements are usually not necessary during installation. Installation cost varies based on the quality of the solar cells and the size of the roof space being utilized. Average installation cost in the bay area (2006-'07) was $8.68/ watt with a rebate from the power provider of about $2.50/ watt. Most panels have a power warranty of 25 years. (1) Meaning that at year 25 they are guaranteed to produce 80% of their original output. A 1kW cell can be expected to produce between 1,278 and 1,415 kWh annually.(1) Based on current efficiencies, a phtotvoltaic system will pay for itself in ten years or less, leaving no less than 15 years of cost free energy operation. Installing a photovoltaic system can protect consumers from rate spikes and reduce peak loads on the electrical grid. Photovoltaics can be utilized in conjunction with rainwater harvesting systems and (depending on design) extensive green roofing systems. (1) "Tapping the potential of Urban Rooftops Rooftop Resources Neighborhood Assessment" Study by Bay Localize. Oakland, Ca |
Sonoma County Rooftop Resource Inc.