Probably that and "quick start" powerplants already serving this function in the UK. Right. Quick start plants basically convert "stored" energy in the form of

Probably that and "quick start" powerplants already serving this function in the UK. Right. Quick start plants basically convert "stored" energy in the form of natural gas into electrical energy on the grid. The natural gas supply has a chemistry/physics advantage in terms of storage efficiency. (As well as industrial infrastructure already built up.) This would allow us to calculate a target number for the storage cost of batteries which could compete. We can then apply industry trends to see which battery chemistry or power storage technology might become competitive, and when it is likely to achieve that.