Solar in Maine: the 2026 numbers
A household here spending $200 a month on electricity needs roughly a 6.4 kW array, which generates about 8,429 kWh in its first year. Bought outright, it returns its cost in year 8 and is worth $20,128 over 25 years — after discounting, after upkeep, and with no federal credit.
Our answer for Maine: ppa
Of the four options, a ppa has the highest net present value at $20,999 , turning cash-positive in year 1 . Solar stops making sense in Maine above roughly $6.14/W installed — if a quote comes in above that, the answer flips.
What Maine gives you to work with
| Sunlight (specific yield) | 1317 kWh per installed kW per year — NREL PVWatts v8, Portland |
| Average residential rate | $0.286/kWh — EIA, May 2026 |
| Export credit | 100% of retail — Net Energy Billing credits rooftop exports at the full retail rate; the 2023 reforms changed community solar, not rooftop. |
| Federal credit on a purchase | None — §25D expired after December 31, 2025 |
| State incentives | Checked, and there is no cash incentive — reviewed 2026-08-15 |
The four options, run side by side
A household spending $200 a month on electricity, with the array sized to cover its usage, at the default $3.00/W installed cost. This is the same case the calculator below opens on. Net present value discounts future dollars at 5%, so these are not the inflated “lifetime savings” totals a sales quote shows.
| Option | Net present value | Payback | Cost per kWh |
|---|---|---|---|
| Cash purchase You pay for it. No fee, no interest, no escalator. | $20,128 | Year 8 | $0.207 |
| Solar loan Includes the 20% dealer fee that a low-APR solar loan hides in the financed price. | $12,635 | Year 1 | $0.273 |
| Lease You rent the system. The owner keeps the §48E credit. | $16,874 | Year 1 | $0.236 |
| PPA You buy the output per kWh, not the hardware. | $20,999 | Year 1 | $0.200 |
A cash purchase delivers electricity at $0.207/kWh against a retail rate of $0.286 — it undercuts the utility, which is the whole case in Maine.
Best option: PPA — $20,999 net present value over 25 years, paying back in year 1.
| Option | Owns it | 30% credit | Upfront | 25-yr NPV | Payback | Cost/kWh |
|---|---|---|---|---|---|---|
| Cash purchase | You | None | $19,200 | $20,128 | Year 8 | $0.207 |
| Solar loan | You | None | $0 | $12,635 | Year 1 | $0.273 |
| Lease | Provider | Indirect (§48E) | $0 | $16,874 | Year 1 | $0.236 |
| PPA | Provider | Indirect (§48E) | $0 | $20,999 | Year 1 | $0.200 |
What this calculation assumes, and where it can be wrong
Federal credit. The 30% federal residential credit (IRC §25D) expired for systems placed in service after December 31, 2025. A 2026 cash or loan purchase receives no federal credit. Leases and PPAs remain eligible indirectly: the third-party owner claims the commercial credit (IRC §48E) and reflects part of it in the price offered, provided the system is placed in service by December 31, 2027.
Estimated §48E value in a lease or PPA quote: about $2,880 for this system, assuming the provider passes through half the credit. That share is our estimate, not a published figure.
Export credit. Net Energy Billing credits rooftop exports at the full retail rate; the 2023 reforms changed community solar, not rooftop.
State incentives. Maine has no residential solar income tax credit or statewide rebate. Its programme is Net Energy Billing, which credits rooftop exports one-for-one at retail — the 2023 reforms that tightened the rules applied to community solar, not to panels on your own roof. Maine pairs that with the highest retail price in this group outside Alaska, which is what carries the case here.
- Cash purchase: No federal tax credit is applied: IRC §25D expired for systems placed in service after 2025-12-31.
- Solar loan: Financed amount includes a 20% dealer fee, which is why a $0-down loan quote costs more than the same system bought outright.
- Solar loan: No federal tax credit is applied: IRC §25D expired for systems placed in service after 2025-12-31.
- Lease: Pricing assumes the system owner claims the §48E credit and reflects part of it in your quote. The system must be placed in service by 2027-12-31 to qualify.
- PPA: Pricing assumes the system owner claims the §48E credit and reflects part of it in your quote. The system must be placed in service by 2027-12-31 to qualify.
Sunlight data: 1317 kWh per installed kW per year (verified — NREL PVWatts v8). Retail rate: $0.286/kWh.
Why Maine lands where it does
Across the 50 states we model, Maine ranks #6 on the value of a cash purchase, at $20,128 — behind Rhode Island at $20,152 and ahead ofHawaii at $15,565 . The ordering is not the one people expect, and the reason is worth stating plainly: sunshine matters less than the price of the electricity you stop buying.
Maine gets 1317 kWh per installed kW per year and pays $0.286 per kWh. That is modest sun and expensive power — and expensive power wins. A Maine panel produces less than an Arizona one but each kWh it makes is worth roughly twice as much, which is why the northern, cloudier states dominate the top of the table.
Full retail export, and what it hides
Maine credits exports at the full retail rate — Net Energy Billing credits rooftop exports at the full retail rate; the 2023 reforms changed community solar, not rooftop. That is the friendliest possible treatment, and it is why the numbers above are as strong as they are. It also means a battery buys you almost nothing financially here: if the grid already pays you retail for every exported kWh, storing that kWh to use later saves the same amount it would have earned. The value of storage in a full net-metering state is close to zero, and we say so on the battery calculator rather than selling you one.
The risk to watch is not the arithmetic but the rule. Full retail net metering is the concession utilities lobby hardest against, and California's move to NEM 3.0 cut export value to a quarter of retail. A 25-year model that assumes today's export rule survives all 25 years is making a policy bet, not just a financial one.
What the state actually pays you
Maine has no residential solar income tax credit or statewide rebate. Its programme is Net Energy Billing, which credits rooftop exports one-for-one at retail — the 2023 reforms that tightened the rules applied to community solar, not to panels on your own roof. Maine pairs that with the highest retail price in this group outside Alaska, which is what carries the case here.
So there is no cash incentive to model. That matters more than it used to: while the 30% federal credit existed, a state with no programme of its own was still fine. Now, Maine buyers are on their own entirely, and the whole case has to come from the bill savings.
The financing trap
A solar loan is worth $12,635 here against $20,128 for the same system bought outright — a gap of $7,493. The interest rate is not what causes that. A 20% dealer fee is embedded in the financed price, which is how a "1.99% APR" offer ends up costing more than a bank loan at 8%. It is rarely on the quote. Ask for it by name.
Lease and PPA look different from a purchase for a structural reason: the third-party owner still claims the 30% §48E credit, which a homeowner buying outright can no longer get. How much of that credit reaches you in the price is a negotiation, and we assume half. The owner also carries the upkeep and the inverter replacement that a buyer pays for. That is why a third-party option is competitive in Maine in a way it would not have been in 2025. Both are tied to systems placed in service by December 31, 2027 — see the 2027 deadline.
Before you accept a Maine quote
- Confirm it does not apply the expired 30% federal credit.
- Ask what export rate it assumed. Maine credits exports at 100% of retail; if the quote valued every kWh at $0.286, its savings figure is defensible on today’s rules.
- Check the price per watt. Above about $6.14/W the purchase stops paying for itself in Maine.
- Ask for the dealer fee on any financed offer, as a dollar amount.
- If it is a lease or PPA, ask for a placed-in-service commitment — §48E requires the system running by December 31, 2027.
More: the 2026 credit change, when solar is not worth it, our assumptions and sources.