Most economically-suitable locations for pumped hydro have been built out already.
You can always use a ton more concrete and force new locations, but the best locations have already been utilized and scaling law of batteries has brought them to the point where they're more competitive than new hydro for this kind of use.
bryanlarsen
Most economical locations for hydro generation have been built out already. Pumped hydro doesn't require flow like generation does, so there are thousands of times more suitable locations. Those haven't been built out.
Maxion
At least in my country they have. They keep trying to build a facility but anything they come up with, the ROI just isn't there.
bryanlarsen
In other words, there are lots of places they could build, but it's just too expensive to build and/or the value of long term electricity storage is too low.
You can always use a ton more concrete and force new locations, but the best locations have already been utilized and scaling law of batteries has brought them to the point where they're more competitive than new hydro for this kind of use.