[bdbdbdb]

The great thing about this gravity storage system is how easy it is to scale. You just need a hill. Sure, it's not going to deliver the power of pumped hydro, but it's easier to build and much safer to operate. And it's certainly a better design than those concrete block tower designs you occasionally see which are just a windy accident waiting to happen

[Veserv]

If you have a hill then you can just put a water tank at the top and bottom and a pipe with a pump and a generator in-between. Even if your rolling mass was iron, you would only need a tank 8x larger than your rolling mass in volume (2x per dimension) to be equal in storage. Much easier to build and safer than a 300 ton railcar barreling down a hill. Also scales better, has lower operating cost, has lower capital cost, and has less energy loss.

[bdbdbdb]

Well I can't argue with that.