The principle of phase change energy storage of paraffin materials is to use the phase change characteristics of paraffin materials to store and release heat energy. Paraffin wax is a kind of thermoplastic material, which will absorb a lot of heat when it changes from solid to liquid in a specific temperature range. This heat is called latent heat. When paraffin wax changes from liquid to solid, it releases stored heat.

Paraffin is a hydrocarbon mixture extracted from some fractions of petroleum, shale oil or other asphalt mineral oil, and its main component is solid paraffin.