They say the problem with battery energy storage is that they say it’s not long-term; for renewables we need long-term energy storage. Pumped hydro has been used for a hundred years. Nothing high tech or no scalability issues. Just dig two lakes, one above the other, with pumps and generators between them. The costs may be high but those are paid back by savings in zero fossil fuel renewable energy.
Quote:
<< The water can cycle between upper and lower reservoirs for a hundred years or more. Evaporation suppressors — small objects floating on the water to trap humid air — can help reduce water evaporation. In all, the amount of water needed to support a 100% renewable electricity system is about 3 liters per person per day, equivalent to 20 seconds of a morning shower. This is one-tenth of the water evaporated per person per day in the cooling systems of U.S. fossil fuel power stations. >>
<< Australia is installing solar and wind three times faster per capita than the U.S. and is already facing the need for mass storage. It has two systems under construction that are designed to have more energy storage than all the utility batteries in the world put together; another dozen are under serious consideration. None involve new dams on rivers. The annual operating cost is low, and the working fluid is water rather than battery chemicals. >>
A new pumped hydro storage system wil be installed in the Kidston gold mine in Australia, by 2024.
https://cleantechnica.com/2022/01/25/theres-a-new-kind-of-gold-in-them-there-pits/