Solar in New Hampshire

New Hampshire's residential solar policy centers on full retail net metering, mandated by the Public Utilities Commission for systems up to 100 kW with an annual true-up. Eversource NH, Unitil, Liberty Utilities, and the New Hampshire Electric Cooperative all operate under the framework, crediting residential exports at the full retail rate. Customers retain their net-metering terms for the life of their interconnection.

The state's residential incentive is the municipal property tax exemption under RSA 72:62-72, which is opt-in at the town level — a critical detail, since some New Hampshire municipalities have adopted it and others have not. New Hampshire offers no state income tax credit and no sales tax exemption, and there is no SREC market. The federal Section 25D residential credit expired December 31, 2025; leased and PPA systems may still access Section 48E for projects that began construction before July 6, 2026.

The policy direction has been stable on net metering, with the high 100 kW cap providing a durable foundation. The principal limitation is the absence of a state tax credit or production incentive, which is offset by the state's exceptionally high retail rate. Homeowners should verify their municipality's property tax exemption status and lean on the favorable net metering for the bulk of the economic case.

New Hampshire's 4.2 peak sun hours reflect a classic New England resource: productive summers offset by short, often cloudy winter days where output drops sharply. The southern tier (the Nashua–Manchester corridor) runs marginally above the state average, while the White Mountains and the North Country sit below. Hot, humid summers drive air-conditioning load that aligns with peak solar output, while cold winters reduce production but also reduce competing heating load for households heating with gas or oil.

Because New Hampshire retains full retail net metering with an annual true-up, the optimal strategy is the classic maximize-and-bank model. A south-facing array tilted near latitude (~43–44°) captures the most annual kilowatt-hours, and the summer surplus is banked at the full $0.30/kWh retail rate to offset winter consumption — at that rate, the banked credits are extremely valuable. There is no avoided-cost penalty for overproduction.

Snow management is a real operational consideration. Pitched-roof arrays shed snow within a day or two of sun returning, and the lost winter production is a small fraction of annual output, but ground-mount arrays can hold snow longer in New Hampshire's heavy snowfall climate. Mature tree canopy in established southern suburbs is a real shading factor.

New Hampshire's $3.40/W installed cost is above the national average, with a typical 8 kW system around $27,200 before incentives — driven by high Northeast labor rates and permitting overhead. The 30% federal residential credit (Section 25D) ended December 31, 2025, leaving the municipal property tax exemption (RSA 72:62-72) as the primary structural offset. New Hampshire offers no state income tax credit and no sales tax exemption.

Payback near 9.6 years on the 8 kW model is driven almost entirely by the high retail rate (~$0.30/kWh). An 8 kW system generating about 9,400 kWh a year displaces roughly $2,833 in annual spending at that rate, which is why the math works despite the modest solar resource and the above-average cost. Households with high consumption — particularly those heating with electricity or heat pumps — see faster payback than the average.

The municipal property tax exemption is the lever most worth verifying locally, since RSA 72:62-72 makes it opt-in at the town level. Households in municipalities that have adopted the exemption see a stronger case than those in towns that have not. The high retail rate and favorable net metering carry the rest of the case.