PHOTOVOLTAIC ROOFING ELEMENTS AND ROOFS USING THEM

摘要

The present invention relates generally to photovoltaic devices. The present invention relates more particularly to photovoltaic roofing products in which a photovoltaic element is affixed to a roofing substrate. In one embodiment, the present invention provides a photovoltaic roofing element comprising a roofing substrate having a solar reflectivity of greater than 0.25, and one or more photovoltaic elements affixed to the roofing substrate. In another embodiment, the present invention provides a photovoltaic roofing element comprising a roofing substrate comprising a bituminous substrate, and a plurality of colored roofing granules disposed on the bituminous substrate, the roofing substrate having color within the color space of CIE Lab coordinates L* in the range of about 20 to about 20, a* in the range of about -5 to about 5, and b* in the range of -15 to about -5; and one or more photovoltaic elements affixed to the roofing substrate.