How do you and Gravitricity deal with ground water? Wouldn't you require constant pumping to keep water out, using additional energy? Or can they be sealed that well to work for decades without maintenance?
I suspect that if the water table is high enough to cause problems, you'd do pumped hydro storage instead.
A lot of solar power is out in the desert where the water table is hundreds or even thousands of feet below surface.
And pumped storage still doesn't work as you'd need surface area for new lakes. Also, not sure if you'd want to pump out huge amounts of ground water for pumped storage, lowering the water table for everyone.