Researchers over at the National Renewable Energy Lab have reportedly made the first solar cell with an external quantum efficiency over 100 percent. Quantum efficiency relates to the number of electrons-per-second flowing in a solar cell circuit, divided by the number of photons from the energy entering. The NREL team recorded an efficiency topping out at 114 percent, by creating the first working multiple exciton generation (MEG) cell. Using MEG, a single high energy proton can produce more than one electron-hole pair per absorbed photon. The extra efficiency comes from quantum dots 'harvesting' energy that would otherwise be lost as heat. The cell itself uses ant
