Houses with power generation already have an indefinitely-large capacity battery on hand. It's called the grid. If you produce too much power, you push your ex

Houses with power generation already have an indefinitely-large capacity battery on hand. It's called the grid. If you produce too much power, you push your extra into the grid. If you don't produce enough, you pull what you need from the grid. Yes, having local battery storage may allow you to time-shift for pricing reasons. But it won't help power your home. Either you have enough local power production for that or not. If you do, you'll be a net exporter to the grid. If you don't you'll be a net consumer.