Some solar energy adopters wish to use their solar panels in the classic manner – installed on a roof or in their backyard. Still, there are situations where installing a flat solar panel is near to impossible, due to space limitations in places like corporate buildings or where aesthetics matters.
Filling the niche of tight solar power space, Pythagoras Solar has developed a double-pane window, with two glass units placed about one inch apart in a metal frame. The glass is made of several tiles, each having a thin monocrystalline solar cell to harvest the light. The rectangle-shaped tiles, besides allowing daylight to enter through, have internal mirrors reflecting light onto the solar cells. The metal frame is used to dissipate the heat and protect the cells.
The key to the design is a plastic prism, placed on the outside of the glass unit, and the adhesive materials used, said company Vice President Udi Paret. “We manipulate the light with optics so the direct light gets onto the cell and the materials make the heat dissipate,” he explained. Paret also says that the mirrors that concentrate the light onto the solar cells help producing as much electricity as a comparably-sized solar cell placed on a flat roof. The ROI (return on investment) is estimated to be of five years.
Pythagoras Solar has been founded in 2007 and has received $12 million in venture capital, partnering with China Sunergy, providing the solar cells and Flextronics to assemble the final product.