Subject: Re: Pumped hydro battery in Australia
Consumer's Energy, in Michigan, has had a "pumped storage" plant, since the 70s. Off-peak, power is used to pump water up the hill, to a storage pond. On-peak, the water runs back down the hill, and runs turbines to generate power. In recent years, the company has added windmills, so the pond can be used to smooth out the output from the windmills.

Ludington Pumped Storage Power Plant

https://en.wikipedia.org/wiki/...

Steve