On: The case for flywheel storage in the Philippines

[unilynx]

It sounds like quite an engineering challenge and a lot of ground to excavate to store a significant amount of water.

Geothermic energy and CO2 storage sound a lot more useful if you’re going to dig that much

[chongli → unilynx]

I think the idea was to avoid excavating all the ground in the middle. You just cut around the circumference of the piston and along the bottom. The thing I never could understand was how they’d seal the walls of the cylinder against the bore so that water doesn’t fill that space and gush right out the top!