Question: What are solar panels made of and how are they made?

Niamh Ryall answered on 21 Jun 2017:

Usually they are made of crystalline silicon, so usually a tiny Si crystal is pulled out of a vat of melted Si to grow massive pure rod of Si crystal (youtube czochralski process if you’re interested, this is the same as for computer chips). The crystal is also “doped” positive slightly in the crystal. Then it is very carefully sliced into plates that are very thin and doped “negative” at the surface. Then they have materials stuck on the top to stop light reflecting off the surface. Then they are connected to metal contacts front and back. On the front, this is done so there’s not too much metal blocking the light but not so little that the electrons can’t be carried away. Then it’s put into glass and aluminium usually so it can be put on rooftops. There are many other types of cells and other ways of making them but this is the way the ones on most roofs are made.