Interconnection Standards

Note: H.B. 1116, enacted in May 2016, raised New Hampshire's net metering aggregate capacity limit from 50 MW to 100 MW. The bill also directed the Public Utilities Commission to initiate a proceeding to develop new alternative net metering tariffs. This proceeding is currently underway.

New Hampshire requires all utilities selling electricity in the state to offer net metering to customers who own or operate systems up to one megawatt (MW) in capacity that generate electricity using solar, wind, geothermal, hydro, tidal, wave, biomass, landfill gas, bio-oil, or biodiesel. Combined heat and power (CHP) systems that use natural gas, wood pellets, hydrogen, propane, or heating oil are also eligible.* The aggregate statewide capacity limit of all net-metered systems is 100 MW. The New Hampshire Public Utilities Commission is in the process of developing alternative net metering tariffs; customers may continue to interconnect and net meter above the 100 MW aggregate cap, but these customers must switch to the alternative tariffs once they are available.

The PUC's rules for net metering, which distinguish between small customer-generators (up to 100 kilowatts) and large customer-generators (greater than 100 kW and up to 1 MW), include interconnection provisions. Interconnection for large systems is generally governed by each utility’s interconnection practices as set forth in the utility’s tariff filed with the PUC.

The interconnection provisions include timelines for the application process and inspection process, and guidance for technical studies and analysis (if necessary). Utilities generally may not require an external disconnect switch for inverter-based systems that comply with the IEEE 1547 & UL 1741 technical standards. Specific safety requirements apply to non-inverter-based systems.

Utilities may not require customers to purchase or maintain property insurance or comprehensive personal liability insurance to protect against potential liability resulting from the installation, operation, or ownership of the generation and interconnection facility. A mutual indemnity agreement is generally required.

Utilities generally may not require customers who comply with these provisions to meet additional requirements, perform or pay for additional tests, or pay additional interconnection-related charges.

* CHP systems up to 30 kW must have a system efficiency of at least 80% to be eligible. CHP systems greater than 30 kW and up to 1 MW must have a fuel system efficiency of at least 65%. CHP systems may account for a maximum of 4 MW of the state’s aggregate net metering limit.