The Green Geek

45% efficient solar panels around the corner

“One frustration of solar energy is that although it’s free, clean, and inexhaustible, it’s a major challenge to harvest efficiently. Consider what happens when photons of sunlight hit a solar cell: They strike electrons in semiconductor material and send them on their way as an electric current. Although many solar photons carry enough energy to theoretically unleash several electrons, they almost never free more than one. However, in recent tests of semiconductor bits only a few nanometers in diameter—entities known as nanocrystals or quantum dots—researchers have been surprised to find that photons at solar energies commonly unleash multiple electrons.”

via Science News