Solar assessment calculator for your home

Use this solar calculator for a free and independent assessment of the best size solar system for your home, plus an estimate of the cost and your potential bill savings.

The assessment report provides details of systems that best match your energy needs, that will help you approach solar retailers with confidence, and make good decisions about installing solar and batteries.

Try the the SunSPOT solar savings calculator

Using the solar calculator

You will be asked to enter your address and some details of your household’s energy use to find out the system size that suits your household, and:

  • estimate your solar system cost
  • find out how many panels will fit on your roof
  • estimate the time to pay back the cost of your system
  • estimate your annual savings and the amount of solar energy your system will generate
  • discover your potential CO2 reductions per year
  • see how a battery might save you even more.

You choose how much information you enter. SunSPOT will not share your personal data with sales companies or sell or give away your information.

About the SunSPOT solar calculator

There is a lot to consider when installing solar on your rooftop. You need to think about what areas of your roof gets the most sun, if shading from nearby structures block the sun throughout the day, and how the weather may affect which area get the most sun throughout the year.

SunSPOT can help you answer these questions.

SunSPOT uses 3D mapping to read the slope of a roof area and measure the impact of shading on that area from nearby structures. It also uses Bureau of Meteorology weather data to estimate the amount of sunshine that falls on each 0.25 square metres of your roof throughout the year.

SunSPOT is not aligned with any solar company. The tool provides answers to your questions about solar (PV), batteries and potential savings, without being too technical.

It is developed by the University of New South Wales and the Australian PV Institute, and backed by Commonwealth and state governments. For households and businesses thinking about installing solar, it is one of the best places to start your research.

Ready to take the next step?

As the market for solar systems has grown in recent years, so has the number of retailers to choose from.

Solar Victoria maintains a list of solar retailers authorised to participate in the Solar Homes program. Seeking quotes from authorised retailers helps ensure you receive a quality system, installed safely by a trained professional.



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