What grid scale storage are you referring to? The only one I know is pumped hydro, and that's quite iffy efficiency wise, can be expensive, and you need the landscape to do it (I'm personally in a very flat area with nothing for a good thousand miles).
Legit question too. I know we have a bunch of nascent tech, but haven't heard of anything at scale.
Legit question too. I know we have a bunch of nascent tech, but haven't heard of anything at scale.