There are two key different types of thin-film PV semiconductors that you can buy these days: cadmium telluride (CdTe) and copper indium gallium diselenide (CIGS). Equally materials might be deposited directly onto either the entrance or back again on the module floor. Some solar panel brands also give AC modules, https://preechaconcretepile71481.theobloggers.com/42014313/solar-cell-system-for-dummies