Shockley-Queisser limit

The Shockley-Queisser limit, also called the radiative efficiency limit or detailed balance limit, is the maximum theoretical efficiency of a solar cell that uses a single p n junction to collect power, where the only loss considered is radiative recombination inside the cell. William Shockley and Hans-Joachim Queisser first calculated it in 1961, finding a maximum efficiency of about 30 percent at a bandgap of 1.1 electronvolts. Later calculations using measured solar spectra and a back surface mirror raised the theoretical maximum for a single junction cell to about 33.16 percent at a bandgap of 1.34 electronvolts; silicon, the most common solar cell material, has a less favorable bandgap of 1.1 electronvolts and a theoretical maximum of about 32 percent, while today's commercial mono-crystalline silicon cells achieve roughly 24 percent, with the shortfall coming from practical losses such as reflection and shading by wiring. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/