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It’s still one of the most inefficient and expensive ways to store energy.

Just look at the price per kWh storage and the energy density compared to other technologies.

> https://en.wikipedia.org/wiki/Energy_density

That page is way out of date and in general not accurate (thus all the warnings on the table). If you have the space, it's cheapest to do gravity storage with water reservoirs, however you need specific geography for that to happen. If you need to build such a reservoir without assisting geography it would be prohibitively expensive. The only other real option is batteries.

If anyone tries using this as a reason to ban batteries just ask what happened at Calide (turbine exploded, lodging 200kg debris in the roof of its building)

Do you know why gravity isn’t used more as a storage mechanism? It seems like you could use batteries as big capacitors for pumps and have the “real” energy stored in water towers.