Electric power belongs to the energy industry. The definition of power equipment mainly includes power generation equipment and power supply equipment. Power generation equipment mainly includes power station boilers, steam turbines, gas turbines, water turbines, generators, transformers, etc. Power supply equipment mainly includes transmission lines, transformers and contactors of various voltage levels.

Electricity converts primary energy such as coal, oil, natural gas, nuclear fuel, hydropower, ocean energy, wind energy, solar energy and biomass energy into electric energy through power generation facilities, and then supplies it to users as energy industry departments through power transmission and distribution systems.