[ncmncm]

Until there is enough renewable generation capacity to satisfy load and also charge storage, building more renewables is the right place for capital expenditure. After there is enough capacity will be time to build out storage. (Otherwise you would need to burn NG to charge the storage.)

Fortunately, storage cost is falling even faster than wind or solar ever did, so by the time we need much, it will be very, very cheap.

At present the main value in storage is load smoothing, where you don't need much.