Many household things that consume significant energy — air conditioner, water heater, clothes dryer, electric vehicle charger — have some tolerance in when they actually need to run. You don’t care exactly when your electric car is charging as long as it’s charged in the morning, and you don’t care exactly when your water heater is heating, as long as the tank stays hot.
If your water heater could talk to your neighbor’s water heater and agree to avoid heating water at the same time, it would flatten out the demand curve, and help avoid the ups and downs that must be serviced by peaker plants. The water heater could also work aggressively when solar power was plentiful and hold back when clouds went by, to match the intermittency of renewables and require less energy storage.
There’s a huge amount of information about solving climate change in this article. I highly recommend taking a look at it if you’re interested in such things, even just to be humbled by it. There’s a lot to do over the next 15-25 years, so let’s get started!