Researchers from the University of Texas, Austin, Texas and the University of Minnesota, Minneapolis, have discovered a process that can be used to increase the conversion efficiency of solar cells up to 66%. The process transfers hot electrons from quantum dots to an electron acceptor. In typical semiconductor solar cells, photons with energies above the semiconductor's bandgap generate hot electrons, and much of the energy from the hot electrons is lost through heat before it can be captured and used for electricity. This new process uses quantum dots to slow down the cooling process of hot electrons and then captures and transfers them. This allows the addition of energy that is currently lost as heat in conventional solar cells.
"This is a dramatic leap forward in making solar power more cost efficient," states Robert Hines, president of Evolution Solar Corp., Tempe, Ariz. "This has the potential to double solar power output and cut solar payback times in half."
Evolution Solar is currently building a solar demonstration site in partnership with Texas Southern University, to be located at the University's Houston campus. Evolution Solar is also developing a solar demonstration project with the City of Brookshire, Texas. These projects should help Evolution Solar acquire new business in a sector that is growing to compete in the energy industry, which includes BP, Xcel Energy Inc., Penn West Energy Trust, and the Encana Corp.