2 giant lakes. 1 uphill from the other, or one underground. When there’s excess energy you pump water uphill. When you need more you let it back down
yeah, good luck with that one though. it tends to be ecologically problematic, and very, very hard to find places good for this. It has happened, but you can’t just build these things as demand desires.
This is why battery based and thermal based energy storage is taking quite the aggressive focus on research and development right now. Batteries are more of a side effect, and very easily accessible, and thermal storage is probably a lot less popular than it should be.
Generally you can do a similar thing with traditional hydro anyway, plus it produces a base level of power anyway.
How efficient is making hydrogen? If you don’t need a huge facility, it might be easier to just store it that way, so you don’t need giant lakes everywhere.
Less efficient than pumped hydro. Appears to be about 40% for green hydrogen in the round trip vs 80% for pumped hydro with a quick google search.
I am curious what’s involved in the “round trip”? Do you mean to fuel other machines directly with hydrogen?
ok so funny problem, storing hydrogen is currently the next nobel prize. And uh, generating it while theoretically easy, is very power hungry. (less of a problem here though tbf with cheap solar power)
Also producing power from hydrogen is more complicated than you would think. You could do a hydrogen fuel cell, or possibly burn it directly, but since hydrogen tends to sort be very spicy, it’s a little hard sometimes.