Solar & Battery Design Tools for Australia Design Systems, Calculate ROI & Find Installers

Energy Usage

Understanding your household's daily energy consumption is essential for designing an effective solar system in Australia. The average Australian household uses between 20-30 kWh per day, with energy-efficient properties often using significantly less. This consumption reflects Australia's climate, home sizes, and lifestyle patterns, with higher usage during summer months for air conditioning and winter months for heating in southern states.

Before installing solar, consider reducing your energy consumption through improved insulation, energy-efficient appliances, and smart home technologies. This can lower the system size you need and improve your investment returns, especially important given Australia's excellent solar generation potential throughout most of the year.

Note: Actual usage varies depending on property size, building efficiency, climate, and appliances.

Solar System Sizing

You'll need around 6.6kW of solar to match your average Australian household consumption. We recommend sizing between 9.9kW and 13.2kW for optimal results, accounting for daily and seasonal variations. Australia enjoys excellent solar generation potential, with most regions averaging 4-5 kWh/kW/day annually, though this varies significantly between northern and southern states.

A 6.6 kW system in Australia generates approximately 28.1 kWh daily on average, with seasonal variation from 3.34 kWh/kW/day in June to 4.81 kWh/kW/day in February. Australia's high solar irradiance means systems typically generate more electricity per kilowatt than most other countries, making solar particularly cost-effective here.

With solar-only (no battery), a 6.6 kW system provides approximately 50% self-usage in Australia, depending on your consumption patterns, drawing 50% from the grid. Adding a 10 kWh battery increases energy independence to approximately 86% annually, reducing grid reliance to 14%. Battery storage is increasingly valuable in Australia, allowing you to store excess daytime generation for evening use and maximising the value of your solar investment, especially as feed-in tariffs decline.

Feed-in tariffs vary significantly by state and retailer, typically ranging from 5-12 cents per kWh. The federal Cheaper Home Batteries Program (from July 2025) provides around 30% discount on battery installations, improving battery affordability. For accurate battery savings and ROI calculations specific to your location and retailer, use the full Photonik design tool.

Understanding Solar & Battery System Costs

A 6.6 kW solar system in Australia costs approximately $7,661, while adding a 10 kWh battery increases the total to around $12,904. Australia has some of the lowest solar installation costs globally, averaging around $0.89 per watt, significantly lower than the US and Canada, thanks to high competition and the federal STC rebate scheme. Solar-only systems typically pay for themselves in around 5.2 years in Australia, whilst adding battery storage usually extends payback but significantly improves energy independence. The STC scheme reduces upfront costs by 25-30%, and many systems achieve payback in under 5 years, making solar one of the best renewable energy investments available.

The cost breakdown shows estimates for equipment costs, installation labour, and GST. Adjust system size and battery storage to see how it affects total investment and payback periods. Australia has excellent installer coverage nationwide, with Clean Energy Council (CEC) accredited installers operating in all states and territories, providing competitive pricing and quality installations.