The problem is, the potential for buildouts of pumped hydro isn't that large any more. In Europe, most usable areas have been built out, and new projects are li

The problem is, the potential for buildouts of pumped hydro isn't that large any more. In Europe, most usable areas have been built out, and new projects are likely to be denied because anything involving creating dams or bodies of water with rapid differences in water level is incredibly devastating on nature and wildlife.