: a unit of work or energy equivalent to the power of one watt operating for one hour

Example Sentences

Recent Examples on the Web By the end of this year, Asp and his team hope to produce a structural-battery panel capable of achieving 75 watt-hours per kilogram. Daniel Oberhaus, Popular Mechanics, 8 May 2023 The addition of silicon processing costs less than $2 per kilowatt-hour, and produces batteries with energy densities of 350 watt-hours per kilogram and 80 percent charging in under 10 minutes. IEEE Spectrum, 4 May 2023 The Steam Deck’s processor runs at just half that and can typically make it to the two-hour mark in all but the most demanding games with its 40 watt-hour battery. Sean Hollister, The Verge, 25 Apr. 2023 By some estimates, that conversion would require about 504 trillion watt-hours, or TWh, a year. Vivienne Walt, Fortune, 13 Apr. 2023 The new battery’s record-high 500 watt-hours per kilogram energy density was verified by Mobile Power Solutions, an independent test and verification lab in Beaverton, Ore. IEEE Spectrum, 31 Mar. 2023 Here's what to look for to ensure energy savings: ✔️ Check its energy efficiency rating (EER), which is derived by dividing BTUs by power consumption in watt-hours. Dan Diclerico, Good Housekeeping, 30 Mar. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'watt-hour.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1888, in the meaning defined above

Time Traveler
The first known use of watt-hour was in 1888

Dictionary Entries Near watt-hour

Cite this Entry

“Watt-hour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/watt-hour. Accessed 9 Jun. 2023.

Last Updated: - Updated example sentences
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