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A comment on Gravity batteries try to beat chemical ones with winches, weights, mine shafts. Parent comment

Re:Gravity batteries try to beat chemical ones with winches,... by tshaddox on Saturday April 24, 2021 @03:28AM (#26923011)
Isn’t tidal energy just harnessing some of the existing gravitational potential energy of the Moon-Earth system, which is roughly similar to any system that harnesses energy from a massive object falling due to gravity?
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Re:Gravity batteries try to beat chemical ones with winches,... by eraserj on Saturday April 24, 2021 @04:13AM (#26923221)
But again, slowing tidal currents must be drawing energy from somewhere until there is none left.
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Re:Gravity batteries try to beat chemical ones with winches,... by Xylakant on Saturday April 24, 2021 @04:51AM (#26923401)
It basically draws energy from the moon orbiting earth. It could theoretically alter that orbit, but given that the moon/earth system has a lot of mass, the timescale for that to happen is extraordinarily large.
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Re:Gravity batteries try to beat chemical ones with winches,... by tshaddox on Saturday April 24, 2021 @11:03AM (#26925358)
That’s exactly what it’s doing. It’s slowing down Earth’s rotation and speeding up the Moon’s orbit (i.e. moving the Moon further from the Earth).
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