The average efficiency of regular solar panels is 15 percent; thin-film solar cells register a lower efficiency percentage than that. Japan’s National Institute of Advanced Industrial Science and Technology (AIST), however, claims 17.7 percent efficiency for its flexible thin-film CIGS solar cell. To be able to achieve that impressive percentage, AIST devised CIGS technology called “alkali-silicate glass thin layer (ASTL) method.”
The said method can facilitate alkali metal’s addition onto the substrate to form the solar cells, increasing the cell’s conversion efficiency. The company used three different materials as substrates : a ceramic substrate, Teijin Ltd’s transparent plastic film, and a foil made of titanium with a coarse surface. The last substrate, titanium foil, brought about the 17.7 percent record efficiency.
The technology’s nitty-gritty would be unveiled during the 4th Annual Symposium of Research Center for Photovoltaics on July 28-29, 2008