Every claim on this page checked against primary sources on July 29, 2026

Maine solar incentives

Maine is the state where the most useful thing that happened to a homeowner this year is not in the state's own statute database. Public Law 2025, chapter 644, enacted April 6, 2026, creates a new section 3475 of Title 35-A legalizing plug-in photovoltaic and battery systems — up to 420 watts with no electrician, no notice and no utility involvement at all, and up to 1,200 watts with a licensed electrician and a thirty-day notice — and it takes effect on July 29, 2026, the day this page was written. The Revisor's website returns a 404 for that section. Everything else in Maine is steadier than the national coverage suggests: the kilowatt-hour credit net energy billing program is open to every electric utility customer in the state, including customers of consumer-owned utilities, and a financial interest under it may be ownership, a lease or a power purchase agreement. What Maine does not have is a state income tax credit, a sales tax exemption — that one was repealed in 1985 and its empty heading is still printed — or the $62 million Solar for All program the federal government terminated in August 2025.

What Maine's plug-in solar law actually permits

Plug-in solar — panels that connect to an ordinary outlet rather than being wired into a service panel — is common in Germany and has been in a grey zone almost everywhere in the United States. Maine has now written the rules down, and the interesting part is not the wattage but the list of things a utility is forbidden to do.

The statute adds that a utility "may not deny the installation of an eligible system that complies with the requirements of this section." Between them, those provisions remove the entire process that makes small solar uneconomic: there is no application, no study, no fee and no negotiation.

Two limits are worth being blunt about. First, an eligible system may not be used for net energy billing. Exported electricity earns you nothing, so the value is strictly in what you consume on site while the sun is on the panel — which is why the statute describes the purpose as offsetting on-site consumption. Second, the system has to be listed to UL 3700 or a comparable standard from a nationally recognized testing laboratory, or configured to the National Electrical Code as the Electricians' Examining Board adopts it. That standard is what makes the no-permission rule safe, and equipment that does not carry it is not an eligible system.

There is also a provision for people who do not own their roof. A customer installing on a structure they do not own must not compromise the structure or violate building, fire or zoning codes, and must restore the structure on removal. Read together with the 420-watt no-electrician tier, that is the clearest path to renter-accessible solar in any state on this site.

Net energy billing did not end in Maine — one half of it closed

Maine spent several years arguing about the cost of net energy billing, and the reporting has left a widespread impression that the program is over. For a homeowner putting panels on their own roof, it is not, and the distinction is worth getting exactly right because it turns on a single phrase.

Public Law 2025, chapter 430 provides that after December 31, 2025 the Commission may not allow a utility to enter a net energy billing agreement with a distributed generation resource that is interconnected, or planned to be interconnected, on the utility side of a customer's utility meter. That is front-of-meter generation — standalone arrays built to supply subscribers. A rooftop system on the customer side of the meter is a different thing and is untouched by it.

The other half of the confusion is that Maine has two programs and only one is available to households. The Commission's own page labels the kilowatt-hour credit program "available to all electric utility customers" and the tariff rate program "available to non-residential customers." Maine PUC, Net Energy Billing Almost everything written about Maine's net energy billing costs concerns the second one.

Maine sends your expired credits somewhere unusual

Every state on this site that expires unused solar credits lets the utility keep the value. Ohio's credits carry forward indefinitely but are never cashed out; Missouri's expire after twelve months with no compensation. Maine expires credits too — Commission rule Chapter 313 eliminates unused kilowatt-hour credits at the end of each twelve-month rolling period, and the customer "will receive no compensation." Me. P.U.C. Chapter 313

But the statute then does something we have not seen anywhere else.

You still lose the credit. The difference is that it is redirected to low-income energy assistance rather than retained by the utility, which is a genuinely unusual piece of statutory design and one no incentive roundup mentions.

The practical advice is unchanged by it: size a Maine system to your own annual consumption. Credits only offset kilowatt-hour usage charges — fixed charges stay on the bill whatever you generate — and anything you have not used within the rolling twelve months is gone.

Why Maine has no solar tax credit, in the state's own words

Maine Revenue Services publishes a single worksheet, Form 1040ME Schedule A Other Tax Credits Worksheet, that enumerates every other refundable and nonrefundable credit an individual may claim, each with a one-line description of who may claim it. Across that document the word "solar" appears zero times, and so does "energy". Maine Revenue Services, 2025 Schedule A worksheet

The tell that this is a choice rather than an oversight is what Maine does credit. The same list includes a Biofuel Production Tax Credit and a Renewable Chemicals Tax Credit. Maine credits renewable fuels and renewable chemicals. It does not credit renewable electricity at the household.

The sales tax answer is a different shape, and it is our favorite kind: a negative you can point at. Title 36 section 1760 enumerates every exemption from Maine sales and use tax. Subsection 38 is headed "Solar energy equipment" — and there is nothing underneath it except a notation that it was repealed in 1985. Maine's revisor keeps the numbering when a subsection dies, so the heading survives as an empty slot in the list. 36 M.R.S. § 1760(38) What we have not established is how Maine sales tax finally falls on an installation — whether the contractor is treated as the consumer of the materials, which is the ordinary rule in many states for property installed into real estate. That is in the list at the foot of this page.

The property tax exemption is real, and it is not automatic

Arizona's solar property tax rule requires nothing to be filed. California's requires nothing to be filed. Indiana's required a certified statement by January 15, and almost nobody knew. Maine's is in the third category.

Under 36 M.R.S. § 655(1)(V), for property tax years beginning on or after April 1, 2025, solar energy equipment is exempt if all of the energy is used on the site where the property is located — the ordinary rooftop case, stated without conditions. But the paragraph also says that on or before April 1st of the first property tax year for which the exemption is claimed, the taxpayer "shall file a report with the assessor," on a form the State Tax Assessor prescribes. 36 M.R.S. § 655(1)(V)

One dated detail sits inside the same paragraph and is easy to misread as applying to everyone. A third qualifying route — for equipment whose output is all transmitted through the utility for net energy billing credits — is available only where the generator had a fully executed interconnection agreement before June 1, 2024. That cutoff bites export-only and shared projects. It does not touch a rooftop system serving its own site, which qualifies under the first route regardless of when it was built.

Maine draws the licensing line through the middle of the array

Secondary claims about licensing have been wrong in every state on this site that had a license, so this came from the regulator's own rule. Maine has no solar-specific license. What it has is an unusually precise statement of which parts of a solar job require a licensed electrician.

The rest of the same rule is the other half of the line: a complete installation of a photovoltaic system is an electrical installation, installing any component that converts solar energy into electric energy is an electrical installation, and making any electrical connection within such a system or to it is an electrical installation. So the electrical work needs a licensed electrician and the racking does not, which is why a Maine crew on a roof is not all electricians and why that is lawful rather than a corner being cut.

Permits are separate and local-ish: no electrical equipment may be installed or altered until the installer obtains a permit from the Electricians' Examining Board, or from a municipality that has its own electrical inspector. And the new plug-in section does not create an exception — over 420 watts it requires an electrician licensed in the State, the same license as any other job.

So are solar panels worth it in Maine in 2026?

Maine is one of the better remaining states in the country for a residential system, and it is worth saying why in a way that does not oversell it.

Maine has high retail electricity prices and true kilowatt-hour netting. In a state where credits are kilowatt-for-kilowatt rather than a wholesale-derived export rate, every kilowatt-hour you generate is worth what a kilowatt-hour costs you, which is the single largest lever in the arithmetic and one that Indiana and Missouri buyers no longer have. Maine's renewable portfolio standard is climbing rather than expiring, which is the opposite of Ohio's. 35-A M.R.S. § 3210 The property tax exemption is real and the ownership rules are permissive enough that a lease or a power purchase agreement does not disqualify you.

Against that: there is no federal credit, no state credit, no sales tax exemption and no rebate, the Solar for All money that was going to help low-income households was cancelled, credits expire on a twelve-month rolling window, and fixed charges stay on your bill no matter how much you generate. So size to your own consumption, not to your roof, and file the property tax form by April 1.

And for anyone for whom a full rooftop system is not on the table — renters, condominium residents, people who are not going to spend five figures — Maine as of today is the most interesting state in the country. A 420-watt plug-in array that needs no electrician, no permission and no fee is a genuinely new option, and as of the date on this page it is one day old.

What this page does not cover yet

Being explicit about the edges is part of the method. Not yet verified, and therefore not claimed here:

• How Maine sales and use tax actually falls on a residential installation. The exemption was repealed in 1985. Whether the installing contractor is treated as the consumer of the materials, and pays tax on its own purchases, is the ordinary rule in many states and we have not read Maine Revenue Services' guidance on it.
• Whether a rooftop system that exports surplus still counts as having all of its energy "used on the site" for the first route of the property tax exemption. Maine has hundreds of municipal assessors and we found no statewide determination.
• The number of the State Tax Assessor's prescribed exemption form. The statute says the Assessor furnishes it to each municipality and makes it available to taxpayers; we did not locate it.
• How a Maine household registers and sells renewable energy certificates. The portfolio obligation is verified and rising, and the Commission's rule says certificates are not transferred to the utility. The market a homeowner can actually reach is not verified — and in a shared or subscribed project the sponsor commonly keeps them, so ask.
• Any individual consumer-owned utility's terms. Maine is unusual in that the kilowatt-hour credit program reaches them, which makes their terms worth having, and none were read.
• Whether Maine has litigated the Solar for All termination, whether any of the award had been obligated before it was rescinded, and whether any state-funded substitute exists. Maine DOE Resources, Solar for All Efficiency Maine administers Maine's ratepayer-funded programs and its current offerings were not read for this page.
• Whether any Maine utility has published a plug-in solar notification form. The statute requires notice for systems over 420 watts "in a form prescribed by the commission," and the law is one day old.

Each of those is queued. When one is verified it will appear above with its own date, and the change will be listed in the record.