Solar Savings Calculator

How much can solar actually save you in Australia?

For a typical Australian home with a $400–$500 quarterly bill, a 6.6kW solar system generally saves between $1,200 and $1,800 per year. The range depends mainly on how much of your solar generation you use directly (self-consumption) versus exporting it to the grid at a low feed-in tariff rate. Households that are home during the day consistently outperform those away 9–5, because they use more of their own solar and less grid power.

What is a payback period and what's realistic?

Payback period is how many years it takes for your electricity savings to equal the upfront system cost. In Australia, most residential solar systems pay back in 4–8 years depending on system size, location, and usage. After payback, the savings are essentially free - solar panels typically last 25+ years. A 6.6kW system in Sydney or Brisbane paying back in 5 years still has 20 years of savings ahead of it.

Why does postcode matter?

Australia spans four solar irradiance zones based on average peak sun hours per day. Darwin and north Queensland receive around 5.2 hours of peak sun daily. Sydney and Adelaide average around 4.5 hours. Melbourne and Tasmania are closer to 4.2 hours. A 6.6kW system in Darwin generates roughly 25% more electricity per year than the same system in Melbourne - which directly affects both annual savings and payback period.

How are STCs factored in?

Small-scale Technology Certificates (STCs) are a federal government incentive that reduces the upfront cost of solar. The value of STCs depends on your location zone and the system size. The system cost estimates in this calculator already include an average STC discount - the figures shown are approximate installed cost after the rebate is applied. The STC scheme phases down annually until 2030, so systems installed sooner receive more certificates.

Should I add a battery?

A home battery lets you store excess solar generation and use it in the evening instead of exporting it at a low feed-in rate. This improves self-consumption and can meaningfully increase annual savings - particularly for households away during the day who currently export most of their solar. Use the battery payback calculator to see whether adding storage makes financial sense for your situation.