It's not cost effective to store for a very long time. If you stored for a year, and the tanks last 30 years, you only get 30 tanks worth of electricity for th

It's not cost effective to store for a very long time. If you stored for a year, and the tanks last 30 years, you only get 30 tanks worth of electricity for the price of the tank. If you store for a few hours, you get 30*365 tanks worth of electricity for the price of the tank, but you need to factor in the cost of the compressor and generator. Presumably there's some balance when you're getting best value out of the compressor and generator, but don't need an excessive number of tanks.