An Etymological Dictionary of Astronomy and Astrophysics

A unit of energy equivalent to one kilowatt (1 kW) of power expended for one hour (1 h) of time. The kilowatt-hour is not a standard unit in any formal system, but it is commonly used to measure the consumption of electrical energy. To convert to → joules, use:
1 kWh = 3.6 × 10⁶ J = 3.6 × 10¹³→ ergs.

See also: → kilo-; → watt-hour.