Solar Payback in 2026 Without the 30% Credit: Add Roughly Four Years
2026-09-18
Short answer: The federal residential clean energy credit (§25D) is not allowed for expenditures after 31 December 2025, and an expenditure counts as made when installation is completed — not when you paid. A $24,000 system saving $1,900 a year paid back in 8.8 years with the credit; in 2026 the same system takes 12.6 years. Any payback figure quoting a 30% credit is describing a system installed in 2025 or earlier.
What changed
Public Law 119-21, signed on 4 July 2025, ended the federal residential clean energy credit (Internal Revenue Code §25D) for expenditures made after 31 December 2025. The IRS guidance adds the detail that decides borderline cases: an expenditure is treated as made when the original installation is completed, not when it was paid for. A deposit paid in 2025 on a system commissioned in 2026 does not qualify.
For a homeowner quoting solar in 2026 this removes 30% of the system cost from the arithmetic. Most payback figures still circulating were computed with that 30% in place.
The arithmetic
simple payback years = net installed cost ÷ annual bill saving
annual bill saving = kWh offset per year × price per kWhWorked example — a 24,000 system offsetting 10,400 kWh a year at the September 2026 national average of 18.3¢/kWh, an annual saving of 1,903:
| Installed | Net cost after federal credit | Payback |
|---|---|---|
| 2025 (30% credit) | $16,800 | 8.8 years |
| 2026 (no federal credit) | $24,000 | 12.6 years |
The system, the roof and the saving are identical. The tax year moved the answer by 3.8 years.
Why the electricity rate now dominates
With 30% of the cost removed by a federal credit, payback was relatively insensitive to local rates. Without it, the rate is the whole story, because it is the only thing setting the numerator’s opponent:
| Your electricity rate | Annual saving on 10,400 kWh | Payback on $24,000 |
|---|---|---|
| 12¢ | $1,248 | 19.2 years |
| 18.3¢ | $1,903 | 12.6 years |
| 25¢ | $2,600 | 9.2 years |
| 32¢ | $3,328 | 7.2 years |
A national “solar pays back in about nine years” headline is now true in some states and off by more than a decade in others. There is no useful national answer to this question in 2026.
What still improves the number
- State and utility incentives. Unaffected by the federal change and now the largest remaining subsidy in many markets. Subtract everything you actually qualify for before dividing.
- Your own production estimate. Roof orientation, pitch, shading and latitude move annual output by a wide margin. A quote that assumes an unshaded south-facing roof and does not have one is quoting a payback you will not get.
- Self-consumption versus export. Where exports are credited below the retail rate, power you use yourself is worth more than power you sell. Shifting large loads into daylight hours raises the saving without changing the system.
- Cash rather than finance. A loan adds interest to the net cost. At 7% over 15 years, a
24,000 system costs about38,800 in total, and simple payback on a $1,900 saving goes past 20 years.
What would reverse the conclusion
A long payback is not automatically a bad decision. Three things sit outside this arithmetic and can legitimately change it: a rate that you expect to keep rising faster than general inflation, which shortens every future year’s payback; a battery or outage-resilience requirement, which is bought for a reason other than payback; and a planned sale, where what matters is the effect on sale price, not the twelve-year break-even you will never reach.
Run your own numbers in the appliance running cost calculator →