PV in Buildings
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Building-integrated photovoltaics (BIPV) are photovoltaic materials that are used to replace conventional building materials in parts of the building envelope such as the roof, skylights, or facades. They are increasingly being incorporated into the construction of new buildings as a principal or ancillary source of electrical power, although existing buildings may be retrofitted with BIPV modules as well.The advantage of integrated photovoltaics over more common non-integrated systems is that the initial cost can be offset by reducing the amount spent on building materials and labor that would normally be used to construct the part of the building that the BIPV modules replace. In addition, since BIPV are an integral part of the design, they generally blend in better and are more aesthetically appealing than other solar options. These advantages make BIPV one of the fastest growing segments of the photovoltaic industry.

Roof tiles and roof membranes with integrated PV cells can now be purchased. With the exception of Japan, where a combination of government incentives for PV and a high proportion of new houses being prefabricated allowed BIPV to be a part of a substantial number of new homes, substantial progress of BIPV has been restricted by the relatively high cost or limited availability of BIPV modules. The French government put in place a large subsidy for BIPV modules vs. standard modules in 2006. This is expected to stimulate BIPV installations in preference to standard modules.

Architects and specifiers have long asserted that BIPV would come into its own only after Return on Investment (ROI) could be achieved in fewer than 10 years. Following five years of research and development supported by a Federal grant and its own corporate investment, a US company, CENTRIA Services Group (CSG), in partnership with United Solar Ovonics announced the development of standards for standing seam roof with integrated thin film PV and product that can be applied to any manufacturer's standing seam product at fabrication. These standards will allow architects and designers to make a number of key decisions early in the design phase that will produce the optimum achievable results. Approaching the end of 2007, about half the nation's manufacturers of standing seam roof systems have opted in to the CSG program. This widespread adoption bodes well for rapid acceptance by owners and developers and the added benefit of returning larger volumes of renewable energy to the grid, reducing the country's dependence upon domestic coal and foreign oil.