[raxxorraxor]

It is certainly an unsolved problem but there are nice ideas floating around. I don't know about feasibility or scalability but some suggest to just elevate land with fluid pressure or they suggested air filled tanks that are drawn to the bottom of seas so that energy is generated from buoyancy. That latter approach allegedly can be scaled to multiple GWh.

Sure, you need a deep see and installation is difficult but the latter approach has the advantage of not needing pumps, which are usually maintenance heavy.

[throwoutway]

Where can I read more about the air filled tanks being “scaled to multiple GWh”?