Even if it only reduces storage demands it seems potentially worthy. May I add a proposal to convert the mediteranian sea into a pumped hydro storage with long

Even if it only reduces storage demands it seems potentially worthy. May I add a proposal to convert the mediteranian sea into a pumped hydro storage with long-term capabilities? It would need the same dam as the Atlantropa, but possibly less extreme. There are some basins around northern Africa that might be amenable to slight terraforming, or just a re-activation of Operation Plowshare to blow a cavern which has it's rubble content lifted out and then used for subsurface pumped hydro. Alternatively plan to collapse the cavern roof into itself after filtering persistent radionuclides and waiting for short half-life isotopes to decay. Collapse via conventional quarry techniques (a circle of drilled wells filled with ANFO?) or iteratively with robots that go out towards the center and drill to blast this off somewhat continuously. Then use a nearby water reservoir to pump in-between. Salt content shouldn't matter much except corrosion protection techniques.