Solar (or photovoltaic) cells convert the sun’s energy into electricity. they rely on the the photoelectric effect: the ability of matter to emit electrons when a light is shone on it. The solar cells are made of silicon and other materials which made up of at least 2 semi-conductor layers, one layer called P layer with extra electrons, another is called N layer missing equivalent electrons. When the sun shines on the solar cells, free electrons from the P layer flow to N layer. Then it forms the electrons current. When the sun shines on the solar cells, the sun will realize photons, which contains sun energy. Many of the photons are reflected, pass right through, or absorbed by the solar cell. As these hit the silicon atoms of the solar cell, they transfer their energy to loose electrons, knocking them clean off the atoms. The photons could be compared to the white ball in a game of pool, which passes on its energy to the coloured balls it strikes. E lectrons are freed f