How is system size measured for interconnection in New Hampshire?

The published limits are stated in kilowatts without saying whether that is the inverter alternating current rating or the array direct current rating.

How much of the 100 megawatt statewide cap remains? The per utility megawatt allocations still printed in the published rule are from the superseded 50 megawatt regime and must not be used.

Only the utility holds this figure. Ask before you quote the job.

Is the total peak generating capacity measured in alternating or direct current? The rule does not say.

Only the utility holds this figure. Ask before you quote the job.

New Hampshire solar interconnection rules, tiers and fees

How the size is measured: not published

The published limits here are stated in kilowatts without saying whether that is the inverter rating in alternating current or the array rating in direct current. On a system near a threshold that decides which band it lands in, so the checker asks the question rather than choosing an answer.

Size bands and what each one obliges

Small customer generator, up to 100 kW Size 0 to 100 kW	A total peak generating capacity of not more than 100 kW. The interconnection rules apply on this path, and no application fee or study fee is authorized anywhere in them. The customer may be required to pay for necessary distribution system modifications, with a description of the work and a cost estimate provided for approval first. No application or study fee Customer pays for necessary distribution modifications, with an estimate first No insurance may be required
Large customer generator, above 100 kW to 1 MW Size 100.001 to 1000 kW	Above 100 kW the state interconnection rules do not govern. Interconnection follows each utility interconnection practices as set out in its tariff filed with the Commission, so the fees, screens and timelines are the utility own. Utility tariff interconnection practices rather than the state rules

Small customer generator, up to 100 kW Size 0 to 100 kW

A total peak generating capacity of not more than 100 kW. The interconnection rules apply on this path, and no application fee or study fee is authorized anywhere in them. The customer may be required to pay for necessary distribution system modifications, with a description of the work and a cost estimate provided for approval first.

No application or study fee
Customer pays for necessary distribution modifications, with an estimate first
No insurance may be required

Large customer generator, above 100 kW to 1 MW Size 100.001 to 1000 kW

Above 100 kW the state interconnection rules do not govern. Interconnection follows each utility interconnection practices as set out in its tariff filed with the Commission, so the fees, screens and timelines are the utility own.

Utility tariff interconnection practices rather than the state rules

The screens that decide it

Within the 1 MW net metering ceiling Limit 1000 kW.
Eligibility runs to a total peak generating capacity of up to and including one megawatt, located behind a retail meter on the customer premises.
Aggregate generation under the threshold of concern on this feeder 7.5 percent of line section peak load, a figure only the utility holds.
New Hampshire does not use a 15 percent screen. The threshold of concern is the lower of 7.5 percent of peak feeder demand measured at the substation or 20 percent of peak feeder demand downstream of the point of interconnection, and reaching it lets the utility run load flow, voltage regulation and short circuit studies. More than one net metered unit on a shared secondary also triggers it. Applying a 15 percent screen here would pass projects New Hampshire studies.

Ask the utility this, before you sell it

How much of the 100 megawatt statewide cap remains? The per utility megawatt allocations still printed in the published rule are from the superseded 50 megawatt regime and must not be used.
Is the total peak generating capacity measured in alternating or direct current? The rule does not say.
What is the peak feeder demand at the substation and downstream of the point of interconnection? The threshold of concern takes the lower of two different percentages of two different denominators, and only the utility holds either figure.

Worth knowing before you quote

New Hampshire flatly prohibits insurance: a customer generator may not be required by the distribution utility or the electricity supplier to purchase or maintain property insurance or comprehensive personal liability insurance against liability from installing, operating or owning the generation and interconnection facility. No application or study fee is authorized. The utility must notify the customer within ten business days whether an application is complete, conduct a witness test within ten business days of the certificate of completion, and notify the Commission within ten business days of reaching the cap. Puc 900 contains no storage or export control provisions at all.

Source

New Hampshire Code of Administrative Rules Puc 900, net metering for customer owned renewable energy generation resources of 1,000 kilowatts or less, with RSA 362-A:9

Read and recorded 2026-09-12. Expressly applies to rural electric cooperatives holding a certificate of deregulation, with two named carve-outs, so the New Hampshire Electric Cooperative is bound. The statute speaks to electric distribution utilities and contains no provision for municipal utilities. Note the scope split: the interconnection rules apply only to small customer generators at 100 kW or less, and above that each utility tariff governs instead.

Solar and battery interconnection rules in New Hampshire

Size bands and what each one obliges

The screens that decide it

Ask the utility this, before you sell it

Worth knowing before you quote

What to do with this