Interconnection Standards (Maine)

From Open Energy Information

Last modified on February 12, 2015.

Rules Regulations Policies Program

Place Maine
Name Interconnection Standards
Incentive Type Interconnection
Applicable Sector Commercial, Fed. Government, Industrial, Local Government, Nonprofit, Residential, Schools, State Government
Eligible Technologies Biomass, Geothermal Electric, Hydroelectric, Municipal Solid Waste, Other Distributed Generation Technologies, Photovoltaics, Small Wind, Solar Thermal Electric, Tidal Energy, Wave Energy, Wind
Active Incentive Yes
Implementing Sector State/Territory
Energy Category Renewable Energy Incentive Programs
Applicable Utilities Transmission and distribution utilities

External Disconnect Switch Not required

Insurance Requirements Not required for inverter-based systems up to 1 MW; vary by system size and/or type for other systems

Net Metering Required No

Standard Agreement Varies by system size
System Capacity Limit No limit specified

Date added to DSIRE 2010-01-19
Last DSIRE Review 2013-01-16

References DSIRE[1]


The Maine Public Utility Commission (PUC) adopted interconnection procedures in January 2010. These rules apply to all transmission and distribution utilities operating in the state and apply to all distribution generation (not just renewables). Maine's interconnection procedures, based in part on the Interstate Renewable Energy Council Inc. 2006 Model Interconnection Procedures,* identify four different tiers with corresponding technical screens. These are:

  • Level 1: Small certified generating, inverter-based facilities 10 kilowatts (kW) or less;
  • Level 2: Certified facilities 2 megawatts (MW) or less;
  • Level 3: Non-exporting, certified facilities 10 MW or less;
  • Level 4: Any generating facility that does not qualify for the aforementioned levels of review, and are not subject to jurisdiction of the Federal Energy Regulatory Commission (FERC).

Fees for interconnection requests increase with each Level. A Level 1 request must submit $50 fee; a Level 2 request must submit a fee of $50 plus $1/kW of generator capacity; a Level 3 request must submit $100 plus $1.50/kW of generator capacity; and a Level 4 request must submit an application fee not to exceed $100 plus $2.00/kW. In addition, Level 4 applicants are responsible for fees associated with the interconnection study as well as any utility upgrades required to accommodate the requested interconnection.

The PUC specifies that IEEE Standard 1547 (“Standard for Interconnecting Distributed Resources with Electrical Power Systems”) or IEEE Standard 929 (for inverters less than 10 kW) and the standard UL 1741 for inverters, converters, and controllers as the technical standards of evaluation. Systems are considered to be certified for interconnection if the components have been tested and listed by a Nationally Recognized Testing Laboratory (NRTL) and if they meet the definition of certification under the FERC Order 2006 for Small Generator Interconnection Procedures, according to these standards. Additional controls (such as external disconnect switches) are not permitted when facilities use certified equipment.

Depending on the size of the small generator facility, insurance requirements differ. No insurance is required for inverter-based facilities with rated capacity 1 MW or less. Inverter-based facilities with rated capacity exceeding 1 MW but less than or equal to 5 MW must carry liability insurance with coverage of at least $1 million. Facilities with rated capacity greater than 5 MW must carry liability insurance with coverage of at least $2 million. Insurance coverage for non-inverter-based generating facilities ranges from no insurance (50 kW or less) to $3 million (for facilities greater than 5 MW).

* IREC updated its model interconnection procedures in 2013. The 2013 model is available on IREC's website.
The information provided here covers several important classification criteria and provides a brief summary of the procedures. Consult the actual rule for official definitions, additional restrictions, and comprehensive information on the technical screens.

Incentive Contact

Contact Name Mitchell Tannenbaum
Department Maine Public Utilities Commission
  1. 18 State House Station

Place Augusta, Maine
Zip/Postal Code 04333
Phone (207) 287-3831


Authorities (Please contact the if there are any file problems.)

Authority 1: Resolve, Chapter 183, 123rd Legislature
Date Enacted 2008-04-07

Authority 2: 2009-219: Order Adopting Interconnection Rule
Date Enacted 2010-01-04

Authority 3: CMR 65-407-324
Date Enacted 2010-01-04

  • Incentive and policy data are reviewed and approved by the N.C. Solar Center's DSIRE project staff.[1]


  1. 1.0 1.1  "Database of State Incentives for Renewables and Efficiency (DSIRE)"