Solar Incentives in Maine
Maine homeowners considering solar in 2026 have access to several active state-level programs. The Renewable Energy Investment Exemption provides a 100% property-tax exemption for eligible solar equipment; property owners must file an application with their municipal assessor by April 1 of the first year the exemption is requested, using forms and guidance published by Maine Revenue Services. For bill offsetting, Maine's Net Energy Billing (NEB) kWh Credit Program allows residential electric customers to receive kilowatt-hour credits for output from a rooftop system or a share of a larger project located within the same utility service territory; unused credits expire after 12 months. A separate NEB Tariff Rate Program provides dollar-denominated credits to non-residential customers at rates set by the Maine Public Utilities Commission through 2046. Customers who prefer not to install their own system may instead participate in a community solar project through the shared-project option under the NEB rules. Export credit rates under net energy billing vary by utility and are not uniform statewide. Commercial property owners may also access long-term solar financing through the Efficiency Maine C-PACE program, repaid via a property tax assessment.
On the federal side, the residential Clean Energy Credit under §25D — commonly described as the 30% federal tax credit — expired for systems placed in service after December 31, 2025, under the One Big Beautiful Budget Act (Pub. L. 119-21). Homeowners installing a new system in 2026 do not qualify for that credit, which meaningfully extends simple payback periods compared to recent years.
Maine's residential electricity rate averaged approximately 28.32 cents per kilowatt-hour as of March 2026, among the higher rates in the Northeast. That elevated rate increases the per-kilowatt-hour value of solar self-consumption and bill credits, which partially offsets the loss of the federal credit when estimating payback timelines.
These figures are verified as of June 2026 against official sources; programs and rates change with each legislative session and PUC rate case. The Maine Public Utilities Commission and Maine Revenue Services are the authoritative sources for current program details.
Federal credit update. The federal residential Clean Energy Credit (the 30% “solar tax credit” under §25D) expired for systems placed in service after December 31, 2025. New 2026 residential installs do not qualify; a 2025 install can still be claimed on a 2025 return (IRS Form 5695). What this means for 2026 →
Current solar incentives in Maine
Renewable Energy Investment Exemption
Maine exempts renewable energy equipment, such as solar panels, from property tax. The exemption has applied since April 1, 2020. Property owners must file an application with their municipal assessor by April 1 of the first year the exemption is requested; Maine Revenue Services publishes the application form and guidance (Bulletin No. 29, Solar Energy Equipment Exemption).
| Amount | 100% property tax exemption for eligible renewable energy equipment (e.g., solar panels). |
|---|---|
| Who qualifies | Maine property owners with qualifying renewable energy equipment; one-time application due by April 1 of the first year the exemption is claimed. |
| Administered by | Maine Revenue Services (applications filed with municipal assessors) |
Source: Maine Revenue Services property tax exemptions program page; MRS Bulletin No. 29 Official source →
Net Energy Billing - kWh Credit Program
Maine's Net Energy Billing (NEB) kWh Credit Program lets electric customers offset their bills with kilowatt-hour credits from the output of small renewable generators, including rooftop solar they own or a share of a larger project. The generating facility may be on the customer's property or elsewhere in the same utility service territory, and unused credits expire after 12 months.
| Amount | Bill credits in kWh for the customer's share of generation; unused credits expire after 12 months. |
|---|---|
| Who qualifies | All electric utility customers; renewable generators under 5 MW; entities marketing shared projects to residential or small commercial customers must register with the PUC and provide a disclosure form. |
| Administered by | Maine Public Utilities Commission |
Source: P.L. 2019 c. 478; P.L. 2021 c. 390; Chapter 313 of the MPUC rules Official source →
Net Energy Billing - Tariff Rate Program
Maine's NEB Tariff Rate Program provides dollar-denominated bill credits to non-residential customers for their share of output from renewable generators under 5 MW. The PUC sets the tariff rates; in December 2025 (Docket Nos. 2019-00197 and 2022-00185) it established rate schedules for each calendar year through 2046, with the applicable rate depending on facility size and when the facility was developed. Credits cannot make a bill negative, and unused credits expire after 12 months.
| Amount | Dollar bill credits equal to the PUC-set tariff rate multiplied by the customer's share of facility output; rates set annually by the Commission through 2046. |
|---|---|
| Who qualifies | Non-residential (commercial and institutional) customers; renewable generators under 5 MW. |
| Administered by | Maine Public Utilities Commission |
Source: Chapter 313 of the MPUC rules; MPUC Docket Nos. 2019-00197 and 2022-00185 Official source →
Shared (Community) Projects under Net Energy Billing
Maine's community solar option operates through the Net Energy Billing rules: customers may participate in a larger renewable project on a shared basis with other customers instead of installing their own system. The project must be under 5 MW and located in the same utility service territory as the participants. Entities marketing shared projects to residential and small commercial customers must register with the PUC and give customers a standardized disclosure form covering costs and benefits.
| Amount | Participants receive NEB kWh credits (or tariff-rate dollar credits for commercial participants) for their share of project output; unused credits expire after 12 months. |
|---|---|
| Who qualifies | Electric customers in the same utility service territory as the shared project; projects under 5 MW. |
| Administered by | Maine Public Utilities Commission |
Source: P.L. 2019 c. 478; Chapter 313 of the MPUC rules Official source →
Efficiency Maine Commercial Property Assessed Clean Energy (C-PACE)
Maine's C-PACE program, run by the Efficiency Maine Green Bank, lets commercial property owners finance energy efficiency and renewable energy improvements (including solar) with borrowed capital repaid through a property tax assessment secured by a lien on the property. The assessment structure allows longer-term financing and lets repayment obligations transfer to subsequent owners. The program was authorized by the 2021 C-PACE Act (L.D. 340) and is governed by an Efficiency Maine administrative rule.
| Amount | Financing terms vary by project and capital provider; long-term financing repaid via a property tax assessment. |
|---|---|
| Who qualifies | Commercial property owners in Maine undertaking energy efficiency or renewable energy improvements; available through Efficiency Maine Trust or municipalities that adopt a C-PACE ordinance. |
| Administered by | Efficiency Maine Trust (Efficiency Maine Green Bank) |
Source: L.D. 340 (2021), 'An Act to Allow for the Establishment of Commercial Property Assessed Clean Energy Programs'; Efficiency Maine C-PACE rule Official source →
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Programs verified as of June 2026 against official state and federal sources (each cited above); refreshed quarterly as legislatures and utility rate cases change the rules. How we verify this data. This page is informational only — not tax or legal advice.