Solar Payback Calculator (Australia)
Estimate how much rooftop solar could save you each year, and how long it takes to pay for itself.
Your running total over 20 years
The 20-year figure assumes panels lose 0.5% of output each year and electricity prices rise 3% a year. It doesn't include inverter replacement, which typically costs $1,000–$2,000 once during the system's life.
Printed from ClearCalc (clearcalc.com.au/solar-payback-calculator/). Estimates only, not financial advice.
How solar savings are calculated
Rooftop solar saves you money in two ways:
- Self-consumption: every kWh you use directly from your panels is a kWh you don't buy from the grid at your retail price, often 25–40 cents.
- Exports: solar you don't use is sent to the grid, and your retailer pays you a feed-in tariff for it. Feed-in tariffs are now often only a few cents per kWh.
Because exports earn so much less than the power you avoid buying, the share of solar you use yourself matters most. Households that are home during the day, run the dishwasher, washing machine and pool pump in daylight, or heat water with solar often use 40–60% of their own solar. Households that are out all day might only use 20–30%.
How much will my system generate?
The city figures are typical yearly averages of how many kWh each kW of panels produces per day, after normal losses. Your actual output depends on roof direction, tilt, shading and panel quality. North-facing roofs perform best. East–west splits produce a bit less in total but spread generation across the day.
Is solar still worth it?
For most owner-occupied houses with a decent roof, solar pays for itself in about 3–7 years and panels last 25 years or more. The federal Small-scale Renewable Energy Scheme reduces the upfront price through STCs, which installers usually apply as a discount. Some states offer extra rebates or loans. Get at least three quotes from Clean Energy Council-approved installers.
Frequently asked questions
How long does solar take to pay off in Australia?
Typically 3–7 years. Payback is faster in sunny cities, for households that use a lot of their own solar, and where electricity prices are high.
What size solar system do I need?
6.6 kW is the most common size for homes because it pairs well with a 5 kW inverter. Larger households, or homes with an EV or electric heating, often benefit from 8–13 kW.
Does adding a battery improve payback?
A battery lets you use more of your own solar, but at current prices batteries often take longer to pay back than panels alone. Government battery rebates can change that, so get quotes and compare.
What is a good feed-in tariff?
Feed-in tariffs vary by retailer and state, from 0 cents to around 10 cents per kWh. Many plans with higher feed-in tariffs charge more for the power you buy, so compare the whole plan.
Last reviewed October 2026. This calculator gives an estimate for general information only. Check important figures with the relevant government agency or a licensed professional.