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Solar Payback Calculator

How long a solar installation takes to pay for itself, with the 25-year net return.

Enter values

Results update as you type.

Result

Payback period

9.55 years

First-year saving
$720.00
25-year saving
$27,969.41
Net gain over 25 years
$19,969.41
Return on investment
249.6%
Effective cost per kWh generated
0.0711
Verdict
Pays back comfortably within the panel warranty

Estimates only — incentives, tariffs and actual generation vary by location and installer.

About the Solar Payback Calculator

How long a solar installation takes to pay for itself, with the 25-year net return.

Also known as: solar roi calculator, solar break even, is solar worth it, solar return on investment.

How to use this calculator

  1. Enter installation cost, annual generation, share used directly, import rate per kwh and the other fields.
  2. The result updates instantly as you type — press Calculate (or Enter) at any time.
  3. Review the breakdown shown under the main result.
  4. Use Copy result or Share to save the answer or send a link with your inputs.

Formula

payback = install cost ÷ annual saving (with escalation and degradation)

Worked example

Using the values pre-filled in the calculator above:

  • Installation cost = 8,000
  • Annual generation = 4,500 kWh
  • Share used directly = 40 %
  • Import rate per kWh = 0.28
  • Export rate per kWh = 0.08
  • Annual energy price rise = 4 %
  • Annual degradation = 0.5 %

the calculator returns:

  • Payback period: 9.55 years
  • First-year saving: 720
  • 25-year saving: 27,969.41
  • Net gain over 25 years: 19,969.41