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Battery storage systems make sense only for those who cannot be served by the grid.
Many utilities use "Net Metering", which means your electric meter runs backwards during periods of overproduction, and forward when drawing more than can be generated. You pay the net difference. That is, you pay only for the amount of electricity used over the amount generated by the PV, Wind, etc. This means you are "paid" the full rate for the excess energy generated. Utilities will often limit the amount of energy they will credit you, to the amount actually consumed. Some may pay you at a reduced rate for any excess over the amount consumed.
From a financial and environmental standpoint, battery storage on a grid-intertied system is a bad idea. Remember that batteries are a consumable item that will need replacing, and that charging/discharging them reduces overall system efficiency. Selling energy back to the grid is more efficient, and acts like a battery. You "charge" the grid when producing more than you need, and "drain" the grid when the demands are higher.
A smart setup would size the renewable energy system to produce 100% of the energy consumed in the lowest consumption month. This would theoretically result in 1 month where the electric bill is zero, and all the other months are considerably reduced.
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