“Of coarse what is not mentioned in my Lifted from wiki post is the cost in megawatts of pumping 27 billion US gallons 363 feet uphill at night.”
True, but you do get ‘most’ of it back. 70% in the case of Michigan, but maybe a bit higher with their refurb. But, on a national level, that is still a HUGE loss of energy.
Geothermal energy storage and the earth battery are both capable of storing significantly more energy than pumped hydro for a fraction of the costs. Rocks are literally dirt cheap. The aspect of using high capital low fuel cost nukes as peaker plants is also worth the read.
Use the find in off feature and look at the earth battery or just read the whole thing I did it’s worth the read.