The size of battery storage that’ll be beneficial to you will be dependent on:
- Your households daily energy usage
- How much excess energy your solar power system generates and;
- How much independence you want from the grid
As an example, if you are using 6kWh of the 16kWh your solar power system is generating during the day and you expect to use at least 10kWh of power at night (common for a household with 9-5 pm workers) a 10kWh battery will store this excess power for you to be able to use at night, once your solar power system is no longer generating energy from the sun. This means unless you go over that 10kWh of power you won’t need to use any additional energy from the grid.