Solar Panel ROI Calculator
Find how quickly a rooftop solar system pays for itself and its net savings over a 25-year life.
Show solution steps
What is the Solar Panel ROI Calculator?
A solar ROI calculator weighs the system cost against the yearly bill savings to give a payback period and lifetime return.
How to Calculate
Annual saving = size × sun hours × 365 × tariff. Payback = system cost ÷ annual saving. Net 25-year saving subtracts the cost.
Formula
Payback = System cost ÷ Annual saving
How to Use
- Enter your details in the fields above.
- The result updates instantly as you type.
- Use Copy, Print or Download PDF to save your result.
Frequently Asked Questions
Do subsidies change this?
Yes u2014 enter the cost after any government subsidy. A lower net cost shortens the payback period significantly.
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