Hi @Lapdog, this is actually being trialed by a few people. Old mineshafts provide a beautiful deep hole for gravity storage like this. And this country happens to already have a lot of those.
Check out these in NSW and Qld
https://www.pv-magazine-australia.com/2022/11/28/australian-start-up-to-fast-track-gravity-energy-storage-system/
https://reneweconomy.com.au/gravity-storage-specialist-energy-vault-strikes-big-battery-deal-with-australia-solar-project/
