Kilowatt-hour
The kilowatt hour (symbol: kWÃÂ÷h) is a unit for measuring energy. It corresponds to one kilowatt (kW) of power being used over a period of one hour.The kilowatt hour is commonly used for electrical energy, since it may be easier to understand in a practical context than the proper SI unit for energy, the joule, which is a watt second (WÃÂ÷s). The joule is a comparatively small unit, making numbers quite large.
1 kWÃÂ÷h = 3,600,000 joules.
The kilowatt hour is a commonly used unit of billing for electric utility companies, although many companies are moving to use the unit megajoule(MJ) instead.