[Steve_American]

Scientists Just Discovered a Breakthrough Battery With NO Metals! It uses air, what can be cheaper than air?

The process uses solar and wind electricity to turn air in to a very cold liquid, and stores it until night falls. Then it exposes the very cold liquid air to some waste heat, which boils the air to make a steam like flow of pressurized gas to drive turbines, that spin generators to make electricity. Building cost is low and efficiency is 30% but can be increased to 70% or more.

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[Steve_American]

We could combine these 2 ideas to make it more efficient. At least maybe.
The top post cools air to a liquid and the needs heat to boil it back into high pressure gas to drive turbines of some sort.
The idea in post below uses solar electricity and heat pumps to heat air to use to melt al metal to store the heat for later.
Combined, we could use the liquid air instead of water to be boiled to dive the turbines. Air is denser than water vapor so it should work better than water. It likely will take less heat to make the phase change aka transition from liquid to a gas.

viewtopic.php?f=6&t=181085

[ckaihatsu]

Molten salt is salt which is solid at standard temperature and pressure but enters the liquid phase due to elevated temperature. Regular table salt has a melting point of 800 °C (1472°F) and a heat of fusion of 520 J/g.[1][2]

https://en.wikipedia.org/wiki/Molten_salt


Mineral oil

Electric space heaters sometimes use mineral oil as a heat transfer oil.

https://en.wikipedia.org/wiki/Mineral_oil


A steel 'thermos tower' in Berlin will be the largest heat storage facility in Europe

https://interestingengineering.com/inno ... e-facility