Multiples of a kilowatt-hour (kWh), which is a unit of electricity. One watt hour is equal to one watt of power produced or used for one hour. A one bar electric fire burning for one hour uses, 1,000 watt hours of electricity. 1 kilowatt-hour, (kWh) is one unit 1 megawatt-hour (MWh) is a thousand units 1 gigawatt-hour (GWh) is a million units 1 terawatt-hour (TWh) is a billion units

terawatt-hour, equal to a million megawatts or a billion kilowatts.

Terawatt-hour; one TWh represents one hour of electricity consumption at a constant rate of 1 TW