- cross-posted to:
- technology@lemmy.world
Actually it isn’t if you stop only looking at places that are also suitable as power plant, that is, have a big river flowing through them.
You can do pumped hydro in an old mineshaft.
Can you? To store the energy you need to pump up; to use it you need to flow back down. Where is the ‘down’ or ‘up’ from a mine shaft?
I’d also question if the volume would be worth it.
Edit: maybe you are thinking compressed air?
…the up is at the surface and the down is at the bottom of the mine shaft? I’m not talking about horizontal ones, of course. You let water in, generating power, and then, to regenerate empty space and with that the capacity to again generate power, you spend energy to pump it up.
As to volume, there’s some gigantic mineshafts, but even small ones might warrant small installations it’s not like some pipes and a pump and generator are much of an investment. Of course, don’t try that in a salt mine geology will play an important part.
And lastly: Mineshafts aren’t the only option. There’s a lot of mountains, and they have many sides, and also plateaus and valleys. Build two concrete basins, connect them via pipe, ship in water from somewhere, voila, pumped hydro storage.
I guess I wasn’t clear where on the surface the storage is. Do they still make a dam type area to store the ‘high’ water, or is it just a different part of the mine which is closer to the surface?
I was able to find some mine numbers… yeah; insane. Especially something like an open cut mine which is functionally already lake shaped.