Solar panels in Maine: cost, payback and the rules that matter
Maine homes pay 30.0¢ per kWh for electricity, the 4th highest of 51, up 9.2% in a year. A typical home needs 13 panels. With no federal tax credit they pay for themselves in about 7.8 yrs.
Four facts that decide solar in Maine
1. The sun. One kilowatt of panels makes about 1,300 kWh a year in Portland. Other towns differ a little; the planner works it out for any address.
2. The price of electricity. Every kWh your panels make is worth what you would otherwise pay: 30.0¢ in Maine today.
3. What your utility pays for exports. Most Maine utilities still credit exported solar close to the retail rate, but rules differ by utility and change often.
4. Incentives. The 30% federal Residential Clean Energy Credit (IRC §25D) ended for systems whose installation is completed after December 31, 2025 (One Big Beautiful Bill Act, P.L. We don't know of a statewide income-tax credit for home solar in Maine.
Maine's homes
597,159 households; 74.3% own their home. 384,305 owner-occupied single-family houses: the main market for rooftop solar. The median home was built in 1977; 11.2% heat with electricity.
ACS 2020–2024 5-year estimates, U.S. Census Bureau.
Plan a specific Maine home
Solar in Portland, Maine’s largest city
| City | Sun hrs/day | kWh per kW | Best tilt | Typical kW | Payback (NM) | Payback (NB) | Solar ¢/kWh |
|---|---|---|---|---|---|---|---|
| Portland | 4.5 | 1,300 | 38° | 5.5 | 7.8 yrs | 13.2 yrs | 12.1 |
NM = exports credited at retail (net metering); NB = exports at ~30% of retail (net billing). Systems sized to the Maine average home. $3.00/W, cash, 25 years.
Rule changes that affect Maine
All changes and deadlines →- Federal: In-service deadline for the lease/PPA solar credit · Tax credits
- Federal: National data: solar prices fell to a median $3.60 per watt · Prices
- Federal: Construction-start deadline passed for the lease/PPA credit · Tax credits
- Federal: The 30% homeowner solar tax credit is gone · Tax credits
Questions about solar in Maine
How much do solar panels cost in Maine?
A 5.5 kW system, the size the average Maine home needs, costs about $13,750 to $20,625 before incentives in 2026.
Is solar worth it in Maine?
In the median Maine city, solar pays for itself in about 7.8 yrs if exported power earns the retail rate, or 13.2 yrs if it earns about 30% of retail. Most utilities here still offer some form of net metering; check yours.
Is there a solar tax credit in Maine?
We know of no statewide income-tax credit for home solar in Maine; utilities and cities sometimes offer rebates. The 30% federal credit ended for homeowner systems installed after December 31, 2025.
How many solar panels does a Maine home need?
About 13 panels of 420 watts for the state-average 550 kWh a month. In Portland, 1 kW of panels makes about 1,300 kWh a year.