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Calculator · Updated August 2026
Solar payback period calculator
Enter your cost and system size. Set the utility increase to zero to stress-test it.
Ranked #1 by Solar Power World · Inc. 5000 · 20,000+ installations
The calculator
How long until a purchased system pays for itself?
Assumes you use or export all production at the rate shown. Where export credit is below retail — California, Ohio, Illinois since 2025 — real payback is longer than this.
This is an estimate, not a savings guarantee.
It uses published utility rates, NREL regional sun data and a standard system derate. It does not know your roof orientation, your shading, your usage pattern or what your utility will charge next year. No solar company can honestly guarantee savings, and any that does is describing a model rather than making a promise.
What payback actually means
Payback is the year in which cumulative electricity value equals what you paid for the system. It is the simplest measure and the one most often quoted, and it hides three things that matter.
The three things it hides
Not all production is worth retail
Power you use at the moment it is made offsets electricity at the full retail rate. Power you export is worth whatever your state's export structure pays. In Pennsylvania, New Jersey, Virginia and Maine that is one for one at retail. In California under the Net Billing Tariff it is a fraction. In Ohio it is the generation rate. In Illinois, since January 2025, it is supply-only. Same array, very different payback.
The utility increase is an assumption, not a forecast
Set it to zero above and see what happens. If payback only works at 4% annual increases, the model is carrying the argument rather than the system. Penelec rose 11.9% on June 1, 2026 and PPL's Price to Compare is up roughly 66% since 2020 — but past increases do not guarantee future ones.
There is no federal credit for a homeowner purchase in 2026
The residential credit, 25D, ended for systems purchased after December 31, 2025. Payback calculators built before 2026 subtract 30% from the cost line. This one does not, because it no longer applies to you. What remains under 48E belongs to the owner of the system, which under a power purchase agreement is not the homeowner.
When payback is the wrong question
If you do not have the capital, payback is irrelevant — the comparison is between your utility rate and a power purchase agreement rate, and the system cost never enters it. If you are likely to move within ten years, resale treatment matters more than payback. And if your roof needs replacing inside eight years, the removal and reinstall cost belongs in the calculation and is not in this one.
What moves payback most
In order: your export credit structure, your rate, cost per watt, shading, and orientation. Panel brand is not in the top five. A cost per watt above roughly $3.50 on a straightforward roof is worth questioning, and the figure above shows you yours as you type.
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Who you would be working with
SolarAmerica
We design your system and manage the project; installation is performed by vetted licensed partners in your area. SolarAmerica is not itself the installing contractor.
Questions
The things people actually ask
How long does solar take to pay for itself?
It depends on your rate, your installed cost and your export credit. Enter your own numbers above. Be careful with any published average — the same system pays back very differently in a 1:1 net metering state than in a net billing state.
Is there still a 30% tax credit to subtract?
Not for a homeowner buying a system. 25D ended for systems purchased after December 31, 2025. This calculator does not subtract it.
What is a reasonable cost per watt?
The figure updates as you type. Above roughly $3.50 per watt on a straightforward roof is worth questioning, though complex roofs, panel upgrades and main panel work legitimately raise it.
Does payback matter under a PPA?
No. There is no upfront cost to pay back. The comparison is between the agreement rate and what your utility charges, plus the escalator.
Get the number for your actual roof
About 60 seconds. No cost, no obligation, and we will tell you if solar does not make sense for your home.
Ranked #1 by Solar Power World · 20,000+ installations · Licensed installers