Solar Payback Calculator

How this solar payback calculator works

We estimate how much electricity your panels make each year (system size × daily output per kW × 365), then split it into the solar you use at home and the solar you export. Solar you use saves you your full electricity price; exported solar earns your feed-in rate. Savings are added up year by year until they cover what you paid. That's your payback period.

What we assume

• Panels lose about 0.5% of their output each year, which is typical for modern panels.
• Your electricity price rises by the percentage you enter; your feed-in rate stays flat.
• Inverter replacement, maintenance and any battery aren't included. Many inverters need replacing once within 25 years.

How to get a faster payback

The biggest lever is using more of your own solar: run the dishwasher, washing machine, pool pump or EV charging in the middle of the day. Every kWh you use yourself saves your full electricity price instead of earning the (much lower) feed-in rate.

These results are estimates for general information only, not financial advice. Get quotes from accredited installers and check current rebates before deciding.