Energy from a source such as sunlight is used to lift a mass such as water upward against the force of gravity, giving it potential energy. The stored potential energy is later converted to electricity that is added to the power grid, even when the original energy source is not available. An old and simple application is the driven by a weight, which at 1 kg and 1 m travel can store nearly 10 newton-meters [Nm], joules [J] or watt-seconds [Ws], thus 1/3600 of a watt-hour [Wh], while a typical 18650 cell can hold about 7 Wh, thus 2500 times. Gravity batteries can have different designs and structures, but all gravity batteries use the same properties of physics to generate energy.
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