Not sure you fully realised what is happening there. Think of that whole building as a sort of 'waterless' hydro power dam. The whole building is for energy storage. It is a giant battery. It's not for people to go up and down in elevators. Their original design was a kangaroo crane (the kangaroo crane is an Australian invention I learnt recently 🙂 ) . Anyway, it had six derricks lifting weights. During the day it pulled the weights up using excess power, and as power was needed in the evening it lowered them again, generating power. Even at that stage it was reckoned it had roughly the same efficiency as pumped hydro. The whole idea is in that range of tech you would call 'gravity storage', which includes of course hydro-electric.
But this new system is genius. So much more compact (energy dense you might say) than the earlier crane system.
I wish I still had my foreign trading account. I would buy some shares 🙂
Incidentally, they are building one in your new favourite state, Texas. Which is handy, because they have more wind turbines than any other state 😉
Oh, the other great thing about this system over pumped hydro, is that we don't have a hell of a lot of water in Australia.