kilowatt-hour

American  

[kil-uh-wot-auuhr, -au-er] / ˈkɪl əˌwɒtˈaʊər, -ˈaʊ ər /

noun

1. a unit of energy, equivalent to the energy transferred or expended in one hour by one kilowatt of power; approximately 1.34 horsepower-hours. kWh, K.W.H., kwhr

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kilowatt-hour British  

noun

1. kWh. a unit of energy equal to the work done by a power of 1000 watts in one hour

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kilowatt-hour Scientific  

1. A unit used to measure energy, especially electrical energy in commercial applications. One kilowatt-hour is equal to one kilowatt of power produced or consumed over a period of one hour, or 3.6 × 10 ⁶ joules.

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kilowatt-hour Cultural  

1. A unit of energy: the expenditure of one kilowatt of power for one hour. A toaster running for an hour will use about this much energy.

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Etymology

Origin of kilowatt-hour

First recorded in 1890–95

Compare meaning

How does kilowatt-hour compare to similar and commonly confused words? Explore the most common comparisons:

• kilowatt vs. kilowatt-hour

Example Sentences

See Examples For:

kilowatt-hour

Electricity rates rose 7.1% nationally in 2025, according to the Energy Information Administration’s measure of average retail revenue per kilowatt-hour, and are expected to keep climbing.

From MarketWatch ● Jul. 27, 2026

The chargers also offer an incentive for customers to choose Walmart — Walmart Plus members will receive a 10% discount off an average price of $0.46 per kilowatt-hour of energy at the company’s chargers.

From Los Angeles Times ● Jul. 8, 2026

But as heat pumps run on electricity, he is now paying around 27p per kilowatt-hour, compared with less than 6p for gas that powers a boiler - more than four times as much.

From BBC ● Apr. 15, 2026

The average price of electricity in U.S. cities is up to about 19 cents per kilowatt-hour, according to Federal Reserve data.

From Barron's ● Feb. 24, 2026

One kilowatt-hour per sol is ... it can be anything . . . um ...

From "The Martian" by Andy Weir