Renewables Portfolio Standard (Maine)

From Open Energy Information

Last modified on February 12, 2015.

Rules Regulations Policies Program

Place Maine
Name Renewables Portfolio Standard
Incentive Type Renewables Portfolio Standard
Applicable Sector Investor-Owned Utility, Retail Supplier
Eligible Technologies Biomass, CHP/Cogeneration, Fuel Cells, Geothermal Electric, Hydroelectric, Landfill Gas, Municipal Solid Waste, Other Distributed Generation Technologies, Photovoltaics, Solar Thermal Electric, Tidal Energy, Wind
Active Incentive Yes
Implementing Sector State/Territory
Energy Category Renewable Energy Incentive Programs

Credit Trading Yes (NEPOOL-GIS)

Standard Total: 40% by 2017
Class I (New Resources): 10% by 2017
Technology Minimum No

Date added to DSIRE 2000-01-01
Last DSIRE Review 2013-07-22
Last Substantive Modification
to Summary by DSIRE

References DSIRE[1]


Maine's original Renewable Resource Portfolio Requirement was passed as part of the state's 1997 electric-utility restructuring law. In 1999, Maine's Public Utility Commission (PUC) adopted rules requiring each electricity provider to supply at least 30% of their total electric sales using electricity generated by eligible renewable and certain energy efficiency resources. Actually, at the time of passage, the required percentage of renewables was actually lower than the existing percentage supplied.

Eligible facilities include those up to 100 megawatts (MW) in capacity that use fuel cells, tidal, solar, wind, geothermal, hydro, biomass or municipal solid waste in conjunction with recycling. Electricity generated by efficient combined heat and power (CHP) facilities and other systems that qualify as "small power production facilities" under the federal Public Utility Regulatory Policies Act of 1978 (PURPA) also are eligible.

Since 1999, the renewables portfolio standard (RPS) has been amended several times and two separate classes designated. Class II includes existing renewables, which are eligible to meet the 30% requirement described above. Class I is composed of new renewables that have come on-line after September 1, 2005. Unlike Class II, municipal solid waste facilities and CHP facilities are not eligible for Class I and there are more stringent hydropower qualifying requirements. In addition, new wind installations may exceed 100 MW.

The schedule for the Class I standard is as follows:

  • 1% for the period from 1/1/2008 to 12/31/2008
  • 2% for the period from 1/1/2009 to 12/31/2009
  • 3% for the period from 1/1/2010 to 12/31/2010
  • 4% for the period from 1/1/2011 to 12/31/2011
  • 5% for the period from 1/1/2012 to 12/31/2012
  • 6% for the period from 1/1/2013 to 12/31/2013
  • 7% for the period from 1/1/2014 to 12/31/2014
  • 8% for the period from 1/1/2015 to 12/31/2015
  • 9% for the period from 1/1/2016 to 12/31/2016
  • 10% for the period from 1/1/2017 to 12/31/2017, and for each year thereafter.

The PUC has approved the use of NEPOOL Generation Information System (GIS) certificates (which are similar to renewable-energy credits, or RECs) to satisfy the portfolio requirement. GIS certificates are awarded based on the number of kilowatt-hours (kWh) of eligible electricity generated. GIS certificates used to meet the Class I standard may not also be used to satisfy the Class II standard. There is a 1.5 credit multiplier available for qualifying community-based renewable energy projects (see the Community-Based Renewable Energy Production Incentive for more information).

The PUC sets an alternative compliance payment (ACP) that utilities may pay instead of satisfying the standard by procuring GIS certificates. The PUC set the ACP base rate for the Class I standard at $57.12 per megawatt-hour (MWh) in 2007; this rate is adjusted annually for inflation beginning in 2008. The 2011 ACP rate is $62.10. Revenues from ACPs will be directed to the state's Renewable Resource Fund).

Legislation enacted in 2011 (Public Act 413) requires the PUC to study the renewable portfolio standard. The PUC engaged London Economic International to conduct the analysis. The results were published in January 2012 in the comprehensive report, MPUC RPS Report 2011 - Review of RPS Requirements and Compliance.

Maine Wind Energy Goals

In addition to the above, there are three goals for wind-energy development in Maine: (1) at least 2,000 MW of installed capacity by 2015; (2) at least 3,000 MW of installed capacity by 2020, of which there is a potential to produce 300 MW from facilities located in coastal waters or offshore; and (3) At least 8,000 MW of installed capacity by 2030, of which 5,000 MW should be from facilities in coastal waters or offshore. The first two goals were established in April 2008 (L.D. 2283), and the third was established in April 2010 (L.D. 1810).

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: 35-A M.R.S. § 3210
Date Effective 3/2000
Date Enacted 1999

Authority 2: 35-A M.R.S. § 3210-C
Date Enacted 2006-06-01

Authority 3: CMR 65-407-311
Date Effective 2007-11-06
Date Enacted 2007-10-22

Authority 4: Public Law 413
Date Enacted 2011-06-29

  • 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)"