> Problem is you need enough "on standby" to run full-output indefinitely ... at a cost high enough that you may as well just use them instead of unreliable ren

> Problem is you need enough "on standby" to run full-output indefinitely ... at a cost high enough that you may as well just use them instead of unreliable renewables. There are two components to the cost of a generator: fixed costs and variable costs, the later being mostly fuel. Even if you have enough standby generators and could run them all the time, if the "unreliable renewables" allow you to reduce their power (using less fuel) or even power some of them down completely, it can be a huge cost advantage. It's even better if you add a bit of storage to the mix: since most generators can't power up instantly, with enough storage they could all be completely powered off instead of idling, saving even more fuel and wear.