Current air conditioners can act like a battery, too. A house has a lot of thermal mass, and you can intentionally use it to your advantage. Smart thermostats are commonly integrated with electric utilities such that they can bump the set temp up during times of high cooling demand. Something they could and should set up is additional pre-chilling, so you could preemptively cool your house down a few extra degrees when demand is low, then when demand is high, you wouldn’t pass your set point by much.