说明：  电功率是在该电能是由一个电路传送的速率。权力的单位是瓦特，每秒1焦耳。 电力通常是由电动发电机产生的，但也可以由源如电动电池供给的。它通常是通过一个电力电网供给到企业和家庭用电力工业。电力通常是由千瓦小时（3.6兆焦耳），其功率在千瓦乘以小时运行时间的产品出售。电力公用事业使用的电表，这使运行总计交付给客户的电能量的测量功率。
(Electric power is the rate at which electrical energy is transferred by an electric circuit. The SI unit of power is the watt, one joule per second. Electric power is usually produced by electric generators, but can also be supplied by sources such as electric batteries. It is generally supplied to businesses and homes by the electric power industry through an electric power grid. Electric power is usually sold by the kilowatt hour (3.6 MJ) which is the product of power in kilowatts multiplied by running time in hours. Electric utilities measure power using an electricity meter, which keeps a running total of the electric energy delivered to a customer.)