Solar Payback Calculator
Estimate annual savings and payback period from system cost, generation, self-consumption, electricity rate and feed-in tariff.
Inputs
View resultLive result
Edit inputsAnnual savings
$1,458
Payback period
5.5yrs
10-year net
$6,580
25-year net
$28,450
Net position over 25 years
Save or file this result
- Estimates annual savings and how many years a system takes to pay for itself.
- Uses your system cost, generation, self-consumption, electricity rate and feed-in tariff as inputs.
- Also projects 10-year and 25-year net positions to show longer-term value.
How it works
Annual savings blend the value of the energy you use yourself against the energy you export: savings = generation × (self-use% × rate + export% × feed-in tariff). Self-consumed energy is worth your retail rate; exported energy is worth the lower feed-in tariff.
- Payback period is
system cost ÷ annual savings. - 10- and 25-year net are
savings × years − cost, a simple cumulative position before degradation, bill inflation and maintenance.
Estimates only: for guidance, not a quote or a compliance certificate. Verify against the current AS/NZS standards and a licensed design. The maths runs in your browser. Nothing is sent to Wattbench unless you sign in and deliberately save the result.
Source ledger1 source
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Frequently asked
- Is this calculator free to use?
- Yes. The payback calculator is free and needs no sign-up. It runs entirely in your browser.
- Is my data stored or sent anywhere?
- The calculation runs in your browser. Nothing is sent to Wattbench unless you sign in and deliberately select Save result.
- How accurate are the payback results?
- The savings and payback figures are estimates based on the cost, generation, rates and self-consumption you enter. They are not a quote or a guaranteed return.
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