There is another way - minute by minute pricing. Much of the electric power usage is not required to be right now, and can be deferred - running the refrigerator, A/C, hotwater heater, dishwasher, charging the car, etc. With real time spot pricing information available, the deferrable usages can be deferred until the spot price is cheap.

I bet this could even out demand quite a bit.

With the current flat rate pricing structure, there is no incentive whatsoever to shift demand to blunt spikes.