4 ms·
>Compressing air necessarily raises its temperature. And then if you want to you can transfer that heat elsewhere, go ahead. That's how air conditioners and ref
by schiffern 2y ago
>Compressing air necessarily raises its temperature. And then if you want to you can transfer that heat elsewhere, go ahead. That's how air conditioners and refrigerators work, after all.
The oh-so-clever trick is to transfer heat elsewhere while you're compressing the gas, so you actually reduce back-loading on the piston instead of having it 'fight' the temperature rise. This can be accomplished via water spray, or by compressing a gas bubble that's surrounded by water (eg in the trompe).
By continuously removing heat as you compress the gas, it effectively acts like a train of compressors and intercoolers with an infinite number of stages, ie true isothermal compression. No magic, just physics.
https://news.ycombinator.com/item?id=40278128 https://news.ycombinator.com/item?id=40278128
- pfdietz 2y agoI want to note that in this system, where the heat is stored to reheat the gas at discharge time, you want to produce heat during compression. Doing adiabatic compression means you are storing more heat, and therefore can produce more energy at discharge time, than you could with isothermal compression (for a given storage volume and pressure.) This is unlike traditional CAES, where the air is reheated by burning a fuel. There, fuel use is minimized by isothermal compression.