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There are some videos on Youtube discussing the hypotheticals of this. They're never really very positive about the feasibility. Neither on a small scale nor on a country-wide scale.

If you'd want to store 1kWh at 10m height, assuming no loss at all from heat, friction, etc, you'd need about 4 of those blocks block weighing 10 tons (according to ChatGPT). So you'd need a lot of those blocks to power a house for a day, unless you're very efficient.

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Please don't cite ChatGPT as a source or as a caveat, instead show the actual math, which should only be about high school level; kinetic energy formula ½mv² = e,

In perfect conditions assuming no loss through drag, you're looking at the kinetic energy formula which is ½mv² = E (in joules).

E = 1 kWh = 3,600 kilojoules, velocity v at 10 meters is 14 m/s, so we need to calculate m for v = 14 and E = 3600k, which is just under 36735 kg. "about four of those blocks" is "about" correct.

Simpler to use the potential energy formula, surely.

E = mgh

m = E/gh

m = 3.6 * 10^6 J / (9.8 m/s^2 * 10m) = 3.6735 * 10^4 kg

This is exactly what ChatGPT provided. Me, the person, then chose to describe it as 'about 4'.

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