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by internet_points 283 days ago
I learnt some new concepts here, specific heat capacity vs overall volumetric, things I kind of understood intuitively, but now much clearer:

If I add some fixed amount heat to some fixed volume of water, it might rise by 1℃, while the same volume of concrete rises by 3℃. And by the same logic, on release, that fixed volume of water dropping by 1℃ releases 3x as much heat as when that fixed volume of concrete drops by 1℃.

So if you can max heat water to 100℃, and max heat concrete to 1200℃, and on release you let it go to 10℃ (probably the range is less in practice), then the water can drop 90℃ and the concrete 1190℃, so even if the water releases 3x the amount of heat per ℃, the water just releases 270 (per volume) while the concrete releases 1190 (per volume)

1 comments

Also to add some practicals: you can drive a steam turbine with the concrete temps, but not with the water.

Also, looking at how hot water could theoretically get (decomposes between 2200-3300C), it looks like 1200C is an interesting limit. Above that and you get safety(practical) and cost issues with every material I could find (common salts, pure elements).

Sand just makes sense! Though, don't ever youtube sand battery.

Why not YouTube sand battery? I did it, and nothing much happened.
Previously it was a bunch of overunity nutjobs.
Ahh right, I did see some preppers there, to be fair.
> don't ever youtube sand battery

Huh? I just get stuff related to this article?