Solar Incentives in Maine

Maine's Net Energy Billing (NEB) operates under multiple compensation tracks regulated by the Maine Public Utilities Commission (PUC). Residential customers ≤ 25 kW most commonly use the Kilowatt-Hour Credit Program — net consumption (imports minus exports) billed at retail rate, with surplus credits rolling forward up to 12 months. The Tariff Rate Program is an alternative used more by commercial customers. NEB has been politically contested in Maine; legislative reforms in 2022 and 2024 modified the structure, and ongoing PUC rate cases continue to evaluate program economics. Confirm the current program structure with Central Maine Power (the dominant utility) or Versant Power before signing. Maine's high retail rates ($0.22/kWh, climbing toward $0.27 in CMP territory) keep solar economics workable despite the political volatility around NEB.

Efficiency Maine, the state's energy-efficiency utility, administers heat pump rebates ($600–$2,000 per unit), battery storage rebates ($1,000–$5,000 income-tiered), insulation rebates, and Solar for All (low-income solar deployment). Solar PV is not a primary Efficiency Maine offering for general consumers — most residential PV economics come through the NEB structure rather than direct rebate. Battery storage rebates can be substantial when paired with a NEB-enrolled solar system and stack with the federal Section 48E credit (commercial/leased). The Solar for All program targets low-income households and is funded under the federal IRA Greenhouse Gas Reduction Fund.

Maine state law enables municipalities to adopt property tax exemptions for solar energy systems on residential and commercial property; most municipalities have done so. Filing is via the local town assessor. Confirm with your specific town. Where adopted, the exemption applies to the value added by the solar PV; the underlying real estate continues normal assessment. Battery storage paired with PV is generally covered.

Maine Revenue Service exempts solar PV equipment from sales tax under 36 M.R.S. § 1760(85). The installer applies the exemption at point of sale. Battery storage paired with PV is included in the exemption when supplied as part of a single bundled service.