[rlmorel]

They have a mountain in my state (That the 10th Mountain Division used to train at) where they did that...last I heard they were still using it.

LINK: Northfield Mountain (hydroelectricity facility)

[devane617]

I read recently that a group was proposing a 3,000ft tower for storage of water during excess peak production. The energy produced during release was impressive.

[No.6]

Yep — keep it simple, plus a water tower is, well, a water tower in the ordinary sense too.