Money laundering is a real issue so I understand why they would like to do something like this. Having read through the comments here I can see that a lot of people are opposed but I don’t really get why.

What? You don’t have Google? Options I know of (other than batteries and pumped hydro) : Compressed Air Energy Storage, Thermal Energy Storage, Fly wheels, Hydrogen, Supercapacitors, Gravitational Storage

No, you’re right. It’s not an option for everyone. Which is why I mentioned that there are many other solutions which are similar and over production which is simpler and cheaper

Pumped hydro? Or one of the many other non battery storage options, or just over production

Any time

no