When a photon (a particle of light) hits the solar cell with energy equal to or greater than the band gap, it knocks an electron loose. This creates an electron-hole pair .
Silicon is naturally shiny, meaning it reflects light rather than absorbing it. Engineering a microscopic, textured surface or adding a chemical coating ensures that as many photons as possible enter the cell. Solar Energy: The Physics and Engineering of Ph...
While the physics is elegant, the engineering is where the real-world challenges lie. A raw silicon wafer isn't very efficient on its own; it requires several layers of sophisticated design: When a photon (a particle of light) hits
The engineering frontier is currently focused on and Tandem Cells . While traditional silicon cells have a theoretical efficiency limit (the Shockley-Queisser limit) of about 33%, layering different materials allows the cell to capture different parts of the light spectrum. Engineering a microscopic, textured surface or adding a