The short answer
A 7.7 kW home solar system at U.S. averages costs about $20,020.00 installed and saves about $1,949.72 the first year, so it pays back in about 10.3 years, with no federal tax credit for systems installed from 2026. It's fastest where electricity is dear and sunny: about 5.1 years in California and 8.6 years in Arizona; slower in Washington, about 15.6 years. These assume full net metering; where the utility pays less for exported power, as under California's net billing since 2023, set the export credit and the share you use as it's made, and the payback stretches.
The same system in every state
A 7.7 kW system in each state, at its average installed price, rate and monthly use, with 100% export credit.
| Alabama | 17 years | $11,333.53 | 16.33¢ |
|---|---|---|---|
| Alaska | 9.6 years | $29,147.26 | 29.41¢ |
| Arizona | 8.6 years | $30,505.66 | 15.05¢ |
| Arkansas | 11.8 years | $18,420.82 | 14.37¢ |
| California | 5.1 years | $71,093.65 | 29.75¢ |
| Colorado | 9.6 years | $29,425.34 | 17.17¢ |
| Connecticut | 8.2 years | $38,957.86 | 24.51¢ |
| Delaware | 10.3 years | $25,996.49 | 18.70¢ |
| District of Columbia | 8.5 years | $42,456.76 | 25.98¢ |
| Florida | 9.7 years | $23,227.82 | 14.99¢ |
| Georgia | 11.2 years | $21,171.52 | 15.90¢ |
| Hawaii | 4.5 years | $112,358.19 | 47.18¢ |
| Idaho | 15.3 years | $12,444.75 | 13.37¢ |
| Illinois | 11.6 years | $23,211.97 | 19.32¢ |
| Indiana | 11.7 years | $20,813.98 | 17.02¢ |
| Iowa | 14 years | $17,281.41 | 17.06¢ |
| Kansas | 11.2 years | $22,416.78 | 15.47¢ |
| Kentucky | 13.3 years | $14,750.91 | 13.80¢ |
| Louisiana | 12.2 years | $16,659.02 | 12.87¢ |
| Maine | 6.9 years | $54,318.91 | 32.11¢ |
| Maryland | 8.6 years | $34,238.29 | 21.40¢ |
| Massachusetts | 7.3 years | $49,650.91 | 30.48¢ |
| Michigan | 9.7 years | $31,641.31 | 22.99¢ |
| Minnesota | 14.1 years | $16,712.15 | 17.20¢ |
| Mississippi | 11.2 years | $19,365.51 | 14.43¢ |
| Missouri | 10.8 years | $22,454.36 | 16.02¢ |
| Montana | 12.1 years | $18,469.25 | 15.57¢ |
| Nebraska | 13.5 years | $14,934.77 | 13.54¢ |
| Nevada | 10.6 years | $22,261.05 | 12.72¢ |
| New Hampshire | 8.3 years | $40,922.22 | 27.64¢ |
| New Jersey | 8.1 years | $38,331.68 | 24.61¢ |
| New Mexico | 8.6 years | $33,869.89 | 16.51¢ |
| New York | 7.5 years | $45,856.38 | 28.65¢ |
| North Carolina | 11.3 years | $20,358.92 | 14.95¢ |
| North Dakota | 15.1 years | $11,214.65 | 13.31¢ |
| Ohio | 10.2 years | $26,175.57 | 19.38¢ |
| Oklahoma | 11.5 years | $21,032.11 | 14.82¢ |
| Oregon | 13.5 years | $13,858.05 | 15.92¢ |
| Pennsylvania | 8.8 years | $33,735.09 | 21.77¢ |
| Rhode Island | 7.7 years | $44,642.04 | 28.18¢ |
| South Carolina | 11.2 years | $21,780.21 | 15.76¢ |
| South Dakota | 12.1 years | $19,069.16 | 15.15¢ |
| Tennessee | 19.4 years | $5,710.27 | 13.42¢ |
| Texas | 9.9 years | $23,693.32 | 15.91¢ |
| Utah | 13.2 years | $15,796.76 | 13.31¢ |
| Vermont | 9.5 years | $31,417.44 | 23.84¢ |
| Virginia | 10.1 years | $26,032.29 | 17.64¢ |
| Washington | 15.6 years | $9,698.18 | 14.63¢ |
| West Virginia | 12.9 years | $16,417.64 | 16.31¢ |
| Wisconsin | 11.7 years | $23,567.39 | 19.41¢ |
| Wyoming | 11.8 years | $20,100.98 | 14.43¢ |
How it works
The formula
savings = power used as it's made × rate + power sent out × rate × export credit
payback = installed cost ÷ first-year savings
Assumptions
- Sun: NLR PVWatts v8 (the National Laboratory of the Rockies, formerly NREL) for a 1 kW system of standard panels on a fixed roof mount, 20° tilt, facing south, 14% system losses, at each state's largest city, month by month.
- Netting: the share of solar you use as it's made saves your full rate; the rest goes to the grid and earns the export credit you set. Under full net metering (100%) every kWh saves the full rate. Under net billing, set the export credit and the share used as it's made from your utility's rules or an installer's estimate; this is a monthly estimate, not an hour-by-hour bill.
- Price: EnergySage's marketplace average installed price per watt by state, before incentives (October 2026), or the U.S. average where it lists none. Berkeley Lab's median for completed 2025 installs was $3.60/W.
- No federal credit: the 25D residential clean energy credit ended for expenditures after December 31, 2025 (IRS). State and utility rebates aren't included.
- Over 25 years: output falls 0.5% a year and each year's savings are worked out from it; electricity rates stay at today's (no guess at inflation), and inverter replacement isn't counted.
Worked example: a 7.7 kW system at U.S. averages
- 7.7 kW × 1,394 kWh per kW = 10,736 kWh a year
- Cost: 7.7 × 1,000 × $2.60 = $20,020.00
- First-year savings at 18.16¢: $1,949.72 → 10.3 years
Ways to cut the cost
- Get three quotes and compare the price per watt, not the monthly payment.
- Check your utility's export rules before you size the system; under net billing, a system sized to your daytime use pays back faster.
- Fix the roof first if it's due within 10 years; removing panels to re-roof costs extra.
- Look up state and utility incentives in DSIRE (dsireusa.org).
Questions people ask
How long does it take solar panels to pay for themselves?
For a 7.7 kW system at U.S. averages ($20,020.00 installed, 18.16¢ per kWh, full net metering), about 10.3 years. It depends most on your electricity rate and how sunny your state is: about 5.1 years in California, 8.6 years in Arizona and 15.6 years in Washington at each state's average price, rate and use.
Is there still a federal tax credit for solar?
Not for systems installed from 2026 on. The 2025 budget law (the One Big Beautiful Bill Act) ended the 30% residential clean energy credit (25D): the IRS says it isn't allowed for expenditures after December 31, 2025, and an expenditure counts when the installation is completed. Many pages still quote it. Check your state and utility for their own incentives.
What is net metering and why does it matter?
Under full net metering, power you send to the grid earns the same rate you pay, so every kWh saves the full price. Many states and utilities have moved to net billing, where exports earn less. At U.S. averages, cutting the export credit to 50% stretches the payback from 10.3 years to 13.7 years. California moved new rooftop systems to net billing in April 2023, which credits exports at far less than the retail rate. Set the export credit, and the share of solar you use as it's made, to match your utility's rules.
How much does a solar system cost?
EnergySage's marketplace average is about $2.60 per watt before incentives (October 2026), so about $20,020.00 for 7.7 kW, the median size Berkeley Lab found. Berkeley Lab's median for systems actually installed in 2025 was higher, about $3.60 per watt. Type your own quote for the real answer.
How much power will my panels make?
PVWatts estimates 1,394 kWh a year per kW on average across the states, for a south-facing roof at a 20° tilt: from 922 in Alaska to 1,779 in New Mexico. Shade, a steep or east-west roof and dirty panels make less.