How Much Battery Storage Do You Need for an Off-Grid Home in Australia?

Choosing the right battery size is one of the most important parts of building an off-grid solar system. The right capacity depends on how much electricity you use each day, how much solar you can generate and how long you want your system to operate when solar production is low.

For smaller cabins, sheds or light backup use, around 5kWh of battery storage can be a practical starting point. It can cover essential loads such as lighting, refrigeration, internet equipment and smaller appliances, depending on actual consumption.

For an off-grid home or rural property, 15–16kWh provides more flexibility for overnight use and higher daily energy demand. Larger batteries also reduce the need to combine several smaller units to reach the same storage capacity.

For properties with heavier loads or longer backup requirements, 30kWh or more may be more suitable. This can be useful for larger off-grid homes, workshops and rural properties where energy independence is a priority.

Battery capacity is only one part of the system. Your solar array, inverter size, continuous discharge requirements and seasonal energy use should also be considered.

Need help choosing between 5kWh, 16kWh and 32kWh? Start with your average daily electricity use and work backwards from there.