Solar batteries are the future of home energy. Batteries charge with the excess energy your solar system produces instead of sending it back to the grid. This energy is available for use whenever your usage exceeds your energy production.

Installing batteries is a smart move to make the most of your solar system. But how much capacity do you need?

battery capacity is expressed in kilowatt-hour (kWh) and represents the usable amount of energy in a battery system. The number of batteries and their capacity right for your households depends first and foremost on the energy independence you want. Do you want 100% energy independence – off-grid? Do you need an energy storage system to use in the event of power outage? Or do you simply want to reduce your peak time dependence?

Think about your energy storage in terms of level of energy independence. Obviously, the more energy independence you want, the bigger your battery system will be.

Choosing the right battery storage size also depends on the amount of electricity you use and the size of your also array. If you already have solar on your roof and you’re exporting lots to the grid, you will have enough power leftover to feed your batteries for instance.

Read more about adding batteries to an existing system here.

Sizing a battery system (in a nutshell)

Let’s take for example a household with an average energy consumption of 20kWh per day.  This household uses 70% of the energy at night time and 30% during the daytime. It means a 6kWh daytime usage and a 14kWh night time usage (so 14kWh from the grid). Simple math would show that this household would need a 14kWh storage system to offset 100% of their night time consumption.

If you are considering a battery storage system and would like to determine precisely the battery storage size that would suit your needs and expectations, call Energis on 1300 782 217 or at sales@energis.com.au, one of our solar consultants will talk you through the best option for you and give you a free quote.