Solar Panel Cost in Idaho (2026 Estimate)

BySunMetricLab Editorial Team·Independent solar research and calculators

Data last updated September 10, 2026 · ranks #45 of 50 states for modeled payback

Idaho averages about 4.9 peak sun hours a day (about average for the US) with an approximate residential electricity rate near 11¢/kWh, on the lower end nationally. In the model used here, an 8 kW system in Idaho produces roughly 11,450 kWh a year and trims about $1,300 off annual electricity costs, paying back its net cost in about 13.3 years. Longer paybacks like this are common where power is cheap or sun is limited. In Idaho incentives carry more of the case, and shifting usage into daylight hours matters more.

Estimated system cost and payback in Idaho

Costs assume roughly $3.00/watt installed for Idaho; the net column applies a 30% federal credit for comparison with quotes that include it. Savings and payback use the state's sun hours and rate above.

The 30% federal Residential Clean Energy Credit ended for systems paid for after December 31, 2025 under the 2025 federal budget law. Net-after-credit figures apply only if you still qualify (for example a 2025 expenditure, or a leased system where the installer passes a credit through). Confirm with a tax professional.

What moves the numbers in Idaho

Two inputs drive most of the difference between states: how much sun a system sees and what each offset kilowatt-hour is worth. Idaho's 4.9 sun hours set production, and its roughly 11¢/kWh rate sets what that production saves. The bigger unknowns are your roof, shading, and how your utility compensates exported power, since a lower export rate can pull real savings below the retail-rate figure above.

Net metering and export credits in Idaho

Idaho Power, which serves most of the state, moved new customers with on-site generation from traditional net metering to net billing after an Idaho Public Utilities Commission decision in late 2023. Energy you use as it is produced still offsets the full retail rate, but exports are measured in real time and credited at an export credit rate the utility updates each year, with higher values in summer and in evening hours. Those credits appear as a dollar amount on the bill rather than a bank of kilowatt-hours, and they are worth well under the retail price for most of the year. Systems in place before the December 2019 cutoff keep legacy net metering terms until 2045.

The picture is different in the corners of Idaho served by other utilities. Rocky Mountain Power in the southeast and Avista in the north have continued to offer net metering with kilowatt-hour credits that roll forward month to month, with any surplus at the end of the annual cycle either paid out at a low rate or forfeited depending on the tariff. Cooperatives and municipal utilities set their own terms, so verify the export rules with your specific provider before assuming Idaho Power's structure applies.

Idaho solar incentives beyond the federal credit

Idaho does not offer a solar rebate or a renewable energy credit market, but it has an unusual state income tax deduction for residential alternative energy devices. Under Idaho Code 63-3022C, you can deduct 40 percent of the system cost in the year it is installed and 20 percent in each of the following three years, up to $5,000 per year and $20,000 in total. Because it is a deduction rather than a credit, the cash value depends on Idaho's flat income tax rate, which sits a little above 5 percent as of 2026, so the benefit is real but modest.

Idaho does not exempt solar equipment from sales tax and has no statewide property tax exemption for residential systems, so include both in your cost estimate.

Utilities and rate plans in Idaho

Idaho Power supplies roughly two-thirds of Idaho households from Boise to Twin Falls and Pocatello, with Rocky Mountain Power covering the southeast around Idaho Falls and Avista serving the Panhandle around Coeur d'Alene and Lewiston. Cooperatives and municipal systems fill in rural areas. Residential rates here are among the lowest in the country, generally near ten cents per kilowatt-hour, which stretches payback periods even though the high desert enjoys strong sunshine. Idaho Power offers an optional time-of-day plan and has sought higher fixed customer charges in recent rate cases; a bigger fixed charge cannot be offset by solar, so watch that line item when comparing bills.