As more and more projects seek to attain a goal of site net zero energy, innovative on-site renewable energy solutions are needed. Roof area has traditionally been a limiting factor, constraining site net zero energy buildings to low-rise buildings. Building-integrated photovoltaics (BIPV) have attracted greater attention, as a means to activate greater building enclosure area for power production. BIPV can often substitute for an exterior cladding material, helping to provide a cost trade-off that makes on-site power production more financially viable.
In 2010, WRL evaluated the Pythagoras product for use on a major GSA project, but found the system to still be cost prohibitive for use. This system is now available as a product through Guardian and continues to be a novel way to address multiple building energy and indoor environmental quality issues in one product: solar gain, daylight tranmission, and power production.