[math-fun] solar cell efficiency record

35.4% energy conversion (sun->electric) efficiency achieved. The light was split into 4 spectral bands each handled with a different semiconductor: Ge: 0.67eV Si: 1.1eV GaInAs: 1.41eV GaInP: 1.88eV I don't understand their splitting scheme. Can it be used with scattered sunlight, i.e. which is not coming from just one direction? In any event, it seems to me this whole approach probably is totally uneconomical because Ge and In are rare. http://newsroom.unsw.edu.au/news/science-tech/milestone-solar-cell-efficienc... (Even greater efficiency has been achieved by the same team but using concentrated sunlight.) -- Warren D. Smith http://RangeVoting.org <-- add your endorsement (by clicking "endorse" as 1st step)