Rooftop solar always pays back: partly true
Partly The claim: “Rooftop solar always pays back” Payback runs from 4.3 years in Hawaii to 21.6 in Washington. The federal 30% credit does not apply to systems placed in service after 31 December 2025, and this table does not include it.
9 states under 10 years
For each state we take PVWatts output for 1 kW (1,714 kWh in Hawaii, 1,062 in Washington) and value it at the 2025 home price. System price is our scenario: $2.50, $3.00 or $3.50 a watt. At $3.00 the median payback is 13.5 years.
Counting under 10 years: 16 states at $2.50, 9 at $3.00, 6 at $3.50. So a payback exists in every state on paper, but its length changes with the price per watt by 7 years in the slowest state.
Payback against price of power: r = -0.88
r = -0.88 between price and payback across 51 states; payback = system price per kW over (kWh per kW times price).
Price of power beats sunshine
The sunniest state gets 1,818 kWh per kW and the dullest 1,017, a spread of 79%. Home prices span 11.8 to 40.6 cents, 3.4 times. Because price varies more, it sets the order: Hawaii pays 40.6 cents, Washington 13.1.
All 51 states: 4.3 to 21.6 years at $3.00
| Hawaii | 1,714 | 40.59 | 3.6 | 4.3 | 5.0 | 8.6 |
|---|---|---|---|---|---|---|
| California | 1,687 | 32.54 | 4.6 | 5.5 | 6.4 | 10.9 |
| Massachusetts | 1,277 | 30.48 | 6.4 | 7.7 | 9.0 | 15.4 |
| Rhode Island | 1,295 | 29.46 | 6.6 | 7.9 | 9.2 | 15.7 |
| Connecticut | 1,282 | 29.38 | 6.6 | 8.0 | 9.3 | 15.9 |
| Maine | 1,267 | 27.78 | 7.1 | 8.5 | 9.9 | 17.0 |
| New York | 1,273 | 26.39 | 7.4 | 8.9 | 10.4 | 17.9 |
| New Hampshire | 1,258 | 24.56 | 8.1 | 9.7 | 11.3 | 19.4 |
| District of Columbia | 1,392 | 21.94 | 8.2 | 9.8 | 11.5 | 19.7 |
| New Jersey | 1,324 | 22.63 | 8.3 | 10.0 | 11.7 | 20.0 |
| Vermont | 1,225 | 22.92 | 8.9 | 10.7 | 12.5 | 21.4 |
| Maryland | 1,388 | 19.48 | 9.2 | 11.1 | 12.9 | 22.2 |
| New Mexico | 1,784 | 15.08 | 9.3 | 11.2 | 13.0 | 22.3 |
| Arizona | 1,750 | 15.32 | 9.3 | 11.2 | 13.1 | 22.4 |
| Alaska | 1,017 | 26.09 | 9.4 | 11.3 | 13.2 | 22.6 |
| Michigan | 1,280 | 20.01 | 9.8 | 11.7 | 13.7 | 23.4 |
| Colorado | 1,534 | 15.85 | 10.3 | 12.3 | 14.4 | 24.7 |
| Wisconsin | 1,324 | 18.16 | 10.4 | 12.5 | 14.6 | 24.9 |
| Pennsylvania | 1,241 | 19.30 | 10.4 | 12.5 | 14.6 | 25.1 |
| Nevada | 1,818 | 13.15 | 10.5 | 12.6 | 14.6 | 25.1 |
| Delaware | 1,383 | 17.13 | 10.6 | 12.7 | 14.8 | 25.3 |
| Florida | 1,546 | 15.24 | 10.6 | 12.7 | 14.9 | 25.5 |
| Texas | 1,498 | 15.47 | 10.8 | 12.9 | 15.1 | 25.9 |
| Illinois | 1,308 | 17.69 | 10.8 | 13.0 | 15.1 | 25.9 |
| Alabama | 1,383 | 16.10 | 11.2 | 13.5 | 15.7 | 26.9 |
| Indiana | 1,370 | 16.23 | 11.2 | 13.5 | 15.7 | 27.0 |
| South Carolina | 1,463 | 14.96 | 11.4 | 13.7 | 16.0 | 27.4 |
| Kansas | 1,482 | 14.56 | 11.6 | 13.9 | 16.2 | 27.8 |
| Minnesota | 1,353 | 15.82 | 11.7 | 14.0 | 16.4 | 28.0 |
| Ohio | 1,244 | 16.96 | 11.9 | 14.2 | 16.6 | 28.4 |
| Georgia | 1,413 | 14.73 | 12.0 | 14.4 | 16.8 | 28.8 |
| Wyoming | 1,549 | 13.38 | 12.1 | 14.5 | 16.9 | 28.9 |
| Virginia | 1,343 | 15.28 | 12.2 | 14.6 | 17.1 | 29.2 |
| Utah | 1,541 | 13.07 | 12.4 | 14.9 | 17.4 | 29.8 |
| North Carolina | 1,411 | 14.02 | 12.6 | 15.2 | 17.7 | 30.3 |
| Oklahoma | 1,495 | 13.12 | 12.7 | 15.3 | 17.8 | 30.6 |
| Mississippi | 1,370 | 14.03 | 13.0 | 15.6 | 18.2 | 31.2 |
| Iowa | 1,373 | 13.72 | 13.3 | 15.9 | 18.6 | 31.9 |
| South Dakota | 1,400 | 13.38 | 13.3 | 16.0 | 18.7 | 32.0 |
| Missouri | 1,386 | 13.49 | 13.4 | 16.0 | 18.7 | 32.1 |
| Louisiana | 1,484 | 12.57 | 13.4 | 16.1 | 18.8 | 32.2 |
| West Virginia | 1,199 | 15.41 | 13.5 | 16.2 | 18.9 | 32.5 |
| Tennessee | 1,385 | 13.18 | 13.7 | 16.4 | 19.2 | 32.9 |
| Nebraska | 1,439 | 12.34 | 14.1 | 16.9 | 19.7 | 33.8 |
| Kentucky | 1,340 | 13.24 | 14.1 | 16.9 | 19.7 | 33.8 |
| Arkansas | 1,372 | 12.84 | 14.2 | 17.0 | 19.9 | 34.1 |
| Oregon | 1,130 | 15.37 | 14.4 | 17.3 | 20.2 | 34.5 |
| Montana | 1,316 | 12.98 | 14.6 | 17.6 | 20.5 | 35.1 |
| Idaho | 1,371 | 11.82 | 15.4 | 18.5 | 21.6 | 37.0 |
| North Dakota | 1,326 | 11.81 | 16.0 | 19.2 | 22.3 | 38.3 |
| Washington | 1,062 | 13.11 | 18.0 | 21.6 | 25.1 | 43.1 |
Under 10 years: 16 states at $2.50, 9 at $3.00, 6 at $3.50. Over 20 years: 0, 1 and 5. Range at $3.00: 4.3 to 21.6 years.
CSVYour system
The credit field starts at 0 because the 25D credit ended with 2025. The retail field lowers the value of exports if your utility pays less than the retail rate.
The tax credit and the limits
IRS: the Residential Clean Energy Credit is 30% of costs for property installed 2022 through 31 December 2025 and "is not available for any property placed in service after December 31, 2025" (page retrieved 2 Oct 2026). With it, payback at $3.00 would have been 3.0 to 15.1 years; without it the table above applies.
We have no state export or buyback rates, no financing cost, no degradation and no roof or shade data: the output is one PVWatts point per state.
Map: payback by state
- 4.3 yr to 10.7 yr
- 10.7 yr to 12.7 yr
- 12.7 yr to 14.5 yr
- 14.5 yr to 16.2 yr
- 16.2 yr to 21.6 yr
Darker = a longer payback. Hawaii 4.3, Washington 21.6.
Keep reading
Sources and dates
| Source | Data period | Retrieved | Used here for |
|---|---|---|---|
| NLR (formerly NREL) PVWatts v8 API | typical weather year, 1 kW fixed roof system | 2 Oct 2026 | kWh per kW at one point per state |
| EIA electricity retail sales, annual and monthly (API v2) | annual 2010 to 2025, monthly to Jul 2026 | 1 Oct 2026 | Home price 2025 |
| IRS: Residential Clean Energy Credit | property placed in service 2022 to 2025 | 2 Oct 2026 | End date of the 25D credit |
Questions
Does rooftop solar always pay back?
On this simple model every state has a finite payback, 4.3 to 21.6 years at $3.00 a watt, but only 9 of 51 are under 10 years.
Which states have the shortest payback?
Hawaii 4.3 years, California 5.5, Massachusetts 7.7 at $3.00 a watt.
Which states have the longest?
Washington 21.6 years, North Dakota 19.2, Idaho 18.5.
Is the federal solar tax credit still available?
Not for homeowners whose systems enter service after 31 December 2025, per the IRS page for the residential clean energy credit.
What if my utility pays less for exported power?
Payback scales with the inverse of the value: at half the retail rate it doubles, for example 13.5 to 27.0 years in Indiana.
Where does the price per watt come from?
It is our scenario: $2.50, $3.00 and $3.50 per watt for the installed system. It is not a quote or a market average; enter your own in the calculator.
Does more sun mean faster payback?
Not by itself. Across 51 states the correlation between home price and payback is r = -0.88; price changes the value of each kWh.
How many states pay back in over 20 years?
1 at $3.00 a watt (Washington), 0 at $2.50 and 5 at $3.50.