[Someone]

> At least, we have a proper unit, but I wish they tell us a bit more about how they got a number 7 orders of magnitude larger than the previous one.

The 70TWh isn’t for this mine, but globally. FTA:

“A study last year by the International Institute for Applied Systems Analysis (IIASA) estimated that gravity batteries in abandoned underground mines could store up to 70TWh of energy – enough to meet global electricity demands.”

(See https://iiasa.ac.at/news/jan-2023/turning-abandoned-mines-in...)

[danbruc]

Which again is nonsense as stated. The average world energy consumption is about 3 TW and gravity storages produce exactly zero and can meet no demand at all. 70 TWh would be enough to store about one day of global electricity consumption, for example to smooth out solar and wind.

[TheOtherHobbes]

That's why these projects are called batteries, not generators.

The nuke and fossil lobbies make a big deal out of how renewables are intermittent, and this is one of many practical ways to fix that.

[danbruc]

I understand that but the statement 70 TWh is enough storage capacity to satisfy the world electricity demand makes no sense. Electricity demand is a power not an energy.