Combining rooftop solar power with cool roofing has benefits. According to an article in Architecture Week, a company reports that the output of its solar power system when combined with a cool roof increases 20% due to the improved collection of reflected and diffuse light.
Four companies in Southern California have formed a strategic alliance to promote the installation of photovoltaics with cool roofs. Coat ‘N’ Cool, the cool roof provider, has joined forces with Advanced Powering Services, Montross Companies and Lineside Electric, to capture a larger share of the increasing popularity of solar energy systems by advancing the marriage with cool roofs.
The reflectivity of cool roofs sends more light to the photovoltaic panels from all directions. This may not be as efficient with flush mounted arrays and panels that are not in a position to absorb any of the reflected light waves. But there is no penalty for doing so.
Combining photovoltaics with a cool roof is garnering increasing attention from both the solar industry and Federal Government. In a recently issued “private letter ruling” (P.L.R. 200947027), the Internal Revenue Service determined that the cost of a “highly reflective” roof installed in connection with a rooftop solar panel installation qualifies for the federal investment tax credit . In the letter, the IRS informed the owner of a manufacturing facility that the cost of the improvements to the existing roof qualified for the investment tax credit because the highly reflective roof surface “meaningfully increased” the amount of electricity generated by the PV panels.