watt-hour
noun
: a unit of work or energy equivalent to the power of one watt operating for one hour
Examples of watt-hour in a Sentence
Recent Examples on the Web
The Helios Horizon's previous lithium-ion pack delivered 260 Wh/kg (watt-hours per kilogram, a measure of how much energy a battery holds relative to its weight).
—
Omar Kardoudi
june 12, New Atlas, 12 June 2026
This is good for a modern lithium-ion battery, but far below the company’s claimed 400 watt-hours per kilogram.
—Sujita Sinha, Interesting Engineering, 9 June 2026
Last year, global data centers used 448 trillion watt-hours of electricity, more than all but 10 countries of the world, said the report issued Wednesday.
—ABC News, 3 June 2026
The 71-watt-hour battery supports fast charging, and Acer rates it for up to 30 hours of video playback (specifically on the P6’s IPS panel configuration).
—John Burek, PC Magazine, 29 May 2026
Last month, Southwest Airlines also started limiting each customer to one power bank not exceeding 100 watt-hours, requiring they be kept in the cabin and not in the overhead bin.
—Alison Fox, Travel + Leisure, 21 May 2026
Congratulations, the New York MTA Subway, the most efficient transit line in the USA uses about 170 watt-hours–about the same.
—Brad Templeton, Forbes.com, 14 Apr. 2026
Southwest says spare batteries and power banks must be carried onboard, with terminals protected against short circuits and capacity capped at 100 watt-hours.
—Aidin Vaziri, San Francisco Chronicle, 8 Apr. 2026
Fletcher said Sion Power’s lithium-metal cells are engineered to deliver energy densities exceeding 500 watt-hour per kilogram, compared with approximately 300-350 Wh/kg for today’s most advanced lithium-ion technology.
—Michael Wayland, CNBC, 24 Mar. 2026
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Omar Kardoudi
june 12, New Atlas, 12 June 2026
This is good for a modern lithium-ion battery, but far below the company’s claimed 400 watt-hours per kilogram.
—Sujita Sinha, Interesting Engineering, 9 June 2026
Last year, global data centers used 448 trillion watt-hours of electricity, more than all but 10 countries of the world, said the report issued Wednesday.
—ABC News, 3 June 2026
The 71-watt-hour battery supports fast charging, and Acer rates it for up to 30 hours of video playback (specifically on the P6’s IPS panel configuration).
—John Burek, PC Magazine, 29 May 2026
Last month, Southwest Airlines also started limiting each customer to one power bank not exceeding 100 watt-hours, requiring they be kept in the cabin and not in the overhead bin.
—Alison Fox, Travel + Leisure, 21 May 2026
Congratulations, the New York MTA Subway, the most efficient transit line in the USA uses about 170 watt-hours–about the same.
—Brad Templeton, Forbes.com, 14 Apr. 2026
Southwest says spare batteries and power banks must be carried onboard, with terminals protected against short circuits and capacity capped at 100 watt-hours.
—Aidin Vaziri, San Francisco Chronicle, 8 Apr. 2026
Fletcher said Sion Power’s lithium-metal cells are engineered to deliver energy densities exceeding 500 watt-hour per kilogram, compared with approximately 300-350 Wh/kg for today’s most advanced lithium-ion technology.
—Michael Wayland, CNBC, 24 Mar. 2026
Cite this Entry
“Watt-hour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/watt-hour. Accessed 21 Jun. 2026.
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