Where does this come from, and can I check it?

Water is lifted to a high reservoir when power is cheap and run back through turbines when demand peaks. The figure is taken from International Energy Agency, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Pumped hydro is the world's largest form of storage

Water is lifted to a high reservoir when power is cheap and run back through turbines when demand peaks A pumped storage plant is a hydroelectric station that can also run in reverse, using off-peak electricity to pump water uphill. Round trip efficiency is usually 70 to 80 percent, so a fifth of the energy is lost, but the plant can reach full output within minutes. The idea dates to the 1890s in Switzerland and Italy and still accounts for most installed storage capacity. It sits in Mondo's technology collection, one of 200 facts that each trace back to the reference below.

Where this comes from

International Energy Agency

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Tags: energy-storage, hydro, grid

Pumped hydro is the world's largest form of storage: the short answers

Where does this come from, and can I check it?: Water is lifted to a high reservoir when power is cheap and run back through turbines when demand peaks. The figure is taken from International Energy Agency, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a technology fact?: Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.