Solar Panels in Wyoming, Montana and Idaho: Payback
Compare solar output, power prices and example payback in Wyoming, Montana, Idaho and nearby Mountain West states, and see why cheap power slows payback.
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In this article · 10 sections
Short answer
Solar panels in Wyoming, Montana and Idaho can produce plenty of power. But electricity there is cheap, so each kilowatt-hour (kWh, the unit your utility bills) your panels make saves less money. In our example, payback runs from 14.7 years in Wyoming to 16.4 years in Idaho with full credit for exported power. Your own quote and utility rules can change that a lot.
The example home we used
The numbers below use one example home: a 7 kW system costing $24,500, with 10,500 kWh a year of use and no incentives. See the methodology for the rest. Production comes from PVWatts, a free estimator from the U.S. Department of Energy's National Laboratory of the Rockies. Prices are EIA August 2026 averages for homes.
Sun versus price across the Mountain West
Sun is only half the story. Payback depends on how much power a panel makes and what each kWh is worth. Compare these eight states:
| State (reference city) | Output per kW per year | Residential price | Payback, full credit |
|---|---|---|---|
| Wyoming (Cheyenne) | 1533 kWh/kW | 14.43¢/kWh | 14.7 years |
| Montana (Billings) | 1344 kWh/kW | 15.57¢/kWh | 15.4 years |
| Idaho (Boise) | 1456 kWh/kW | 13.37¢/kWh | 16.4 years |
| Colorado (Denver) | 1595 kWh/kW | 17.17¢/kWh | 12.4 years |
| Utah (Salt Lake City) | 1484 kWh/kW | 13.31¢/kWh | 16.2 years |
| Nevada (Las Vegas) | 1753 kWh/kW | 12.72¢/kWh | 16.1 years |
| New Mexico (Albuquerque) | 1779 kWh/kW | 16.51¢/kWh | 12.8 years |
| Arizona (Phoenix) | 1755 kWh/kW | 15.05¢/kWh | 13.9 years |
The U.S. average residential price was 18.16¢/kWh in August 2026. Every state in the table sits below that. Colorado is the closest at 17.17¢.
Nevada shows the effect best. Las Vegas gets 1753 kWh per kW, far more than Cheyenne. Yet the Nevada price is 12.72¢, so payback is 16.1 years against 14.7 years in Wyoming.
Wyoming
Cheyenne is a strong solar spot for the region, at 1533 kWh per kW per year. The price is 14.43¢/kWh, up from 14.33¢ a year earlier. Year-1 savings with full credit come to $1515 in the example. Payback is 14.7 years with full credit, 20 years at half credit and 24.3 years at quarter credit. See our Wyoming solar page and Wyoming electricity prices.
Montana
Billings produces 1344 kWh per kW, the lowest output in this group. Montana prices rose 9% in a year, to 15.57¢ from 14.29¢. That helps, but example payback is still 15.4 years with full credit. Winter is the challenge: Montana's summer-to-winter ratio is 2.3, so July gives 166 kWh per kW while January gives only 65 kWh. If you are in Missoula or elsewhere in the state, check Montana solar and your own utility's rules.
Idaho
Boise gets 1456 kWh per kW. But Idaho's price is 13.37¢, one of the lowest here, so full-credit payback is 16.4 years. At half credit it is 22 years. At quarter credit the example does not pay back within 25 years. Idaho prices did rise 10.7% in a year, from 12.08¢. If you live near Meridian or Boise, see Idaho solar.
Why cheap power stretches payback
Your savings equal the kWh you offset times your rate. A low rate shrinks the savings, while the system cost stays about the same. Berkeley Lab reports a median installed price of $4.0 per watt for host-owned systems installed in 2024, so a quote may differ from our $3500 per kW example. Learn more in solar cost per watt and payback.
Utility rules matter too. Many places credit exports at less than the retail rate. Our table shows what happens at half and quarter credit, and net metering vs. net billing explains the difference. DSIRE keeps a database of current programs by state.
Winter and snow
Idaho's summer-to-winter output ratio is 2.8, and Montana's is 2.3. Wyoming's is 1.6. A big ratio means summer makes most of your power. If you use more power in winter, a system sized for the year may leave you buying more from the grid. Our winter solar guide goes deeper.
What to do next
- Find your actual rate on your bill and compare it with the state averages above.
- Ask your utility how it credits exported power.
- Get several quotes and compare the price per watt.
- Run your numbers in the solar calculator.
- Check electricity prices and the payback guide.
The federal 30% residential credit is not available for property placed in service after December 31, 2025, so these examples assume no incentives. State or local programs may still apply.
Bottom line
The Mountain West has good sun but low power prices. Wyoming leads this trio at 14.7 years in our example, then Montana at 15.4 and Idaho at 16.4. Colorado and New Mexico do better because their prices or output are higher. Your result depends on your rate, your quote and your utility's export rules. Treat these numbers as estimates, not promises.
Sources
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