Solar battery calculator

Using the battery calculator

The battery payback calculator above is designed for calculating the financial and environmental benefits of adding a battery to an existing solar system.

If you want to explore the viability of a new solar and battery system, we recommend you use our solar and battery calculator.

The battery calculator does not factor in the potential savings delivered by VPP incentives, as they are only paid after a battery has been installed.

Battery payback

Battery payback is measured in years and calculated by dividing the cost of the battery by annual expected savings. There are many variables that affect the payback time for a solar battery, these include:

• Your location
• The rate you pay for electricity
• Your electricity usage habits
• The size of your existing panel system
• Availability of any state or local subsidies

The government rebate on solar batteries is factored into all of our calculations, as it is effectively available to everyone that installs approved products. The national subsidy has significantly improved the payback time on batteries.

The financial viability of a battery will depend on your individual circumstances, for example: the size and generation capacity of your current solar system, the amount of electricity you use and your usage habits during daylight hours.

The economics of battery storage

At the heart of the solar storage equation is what happens with the excess solar energy your solar system produces daylight hours. For solar panel owners that do not have a battery, any excess power is fed straight back into the grid in return for a financial credit per kWh. At night, electricity needs to be bought from the grid, typically at a much higher rate.

A solar system with a battery can instead store this excess energy for use at night. Therefore, the greater the difference between these two rates, the more financially viable the battery is.

In recent years, the disparity between the feed-in tariff and the cost of electricity has got much bigger.
Electricity costs have risen, while feed-in tariffs have decreased. This trend, along with the reduced cost of batteries has seen payback times for solar batteries improve significantly.