Thats not what they’re using it for. This is an alternative to pumped hydro or big lithium arrays.

The article mentions using greener things like waste and soil.

And if you were using redundant mine shaft thats greener than building new structures.

Recycling lithium ion batteries isn’t easy either though, and you might not have the geography for hydro.

Love clever and simple stuff like this.

Big nostalgia feels. The internet was so good back then.