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Renewable Energy Certificates (RECs)

National REC Tracking Systems

Renewable Energy Certificates (RECs) tracking systems provide a basis for creating, managing, and retiring RECs, ensuring that each REC is counted only once.1 REC tracking systems ensure that RECs are only "retired" (used to meet compliance or substantiate a voluntary claim) once by assigning a unique serial number to each megawatt-hour of renewable energy generation, which constitutes a REC.

Any generator that wants to be issued RECs in a tracking system must first register with the tracking system and provide information about the generator (e.g. type of renewable generation, project location). Tracking systems then issue RECs on a regular schedule based on the output of the generator. Output must satisfy the metering and verification requirements specified by the tracking system. RECs are issued to the generator's account, or to the account of an appointed representative. Market participants who have accounts with the tracking systems can transact the RECs; RECs can only reside in one account at a time.

Currently, nine regional REC tracking systems operate in different regions of North America.

Current Regional North American REC Tracking Systems, or Registries
Tracking System Primary Region(s) Launch Date
Texas Renewable Energy Credit Program, run by the Electric Reliability Council of Texas (ERCOT) Texas 2001
NEPOOL-Generation Information System (GIS) New England 2002
PJM-Generation Attribute Tracking System (PJM-GATS) Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia and the District of Columbia 2005
Western Renewable Energy Generation Information System (WREGIS) Alberta, Arizona, British Columbia, Baja California, California, Colorado, Idaho, Montana, Nebraska, Nevada, New Mexico, Oregon, South Dakota, Texas, Utah, Washington, and Wyoming 2007
Midwest Renewable Energy Tracking System (M-RETS) Arkansas, Illinois, Indiana, Iowa, Louisiana, Manitoba, Minnesota, Mississippi, Missouri, Montana, North Dakota, Ohio, Kentucky, South Dakota, Texas, and Wisconsin 2007
North American Renewables Registry (NAR) States and provinces not covered by the regional markets 2009
Michigan Renewable Energy Certification System (MIRECS) Michigan 2009
Nevada Tracks Renewable Energy Credits (NVTREC) Nevada 2007/2008
North Carolina Renewable Energy Tracking System (NC-RETS) North Carolina 2010

Map of National REC Tracking Systems. Click for a text representation of this image.

       For a larger version of this image.


Environmental Tracking Network of North America

Inter-registry transfer capability


APX. (2014). Using Tracking Systems with the Implementation of Section 111(d) State Plans. October.

Quarrier, R. and Farnsworth, D. (2014). Tracking Renewable Energy for the U.S. EPA's Clean Power Plan: Guidelines for States to Use Existing REC Tracking Systems to Comply with 111(d). Center for Resource Solutions and Regulatory Assistance Project. June.

Heeter, J. (2013). Renewable Energy Certificate (REC) Tracking Systems: Costs & Verification Issues (Presentation). NREL (National Renewable Energy Laboratory). 16 pp.; NREL Report No. PR-6A20-60640.

Environmental Tracking Network of North America (ETNNA), 2010. The Intersection Between Carbon, RECs, and Tracking: Accounting and Tracking the Carbon Attributes of Renewable Energy. White Paper, February.

Environmental Tracking Network of North America (ETNNA), 2009. System Changes to Serve a Federal RES. June.

Environmental Tracking Network of North America (ETNNA), 2009. Inter-registry REC Transfers. June.

Lieberman, D. (2004). The Need for Green-e Certification and Verification in an Era of Renewable Energy Tracking Systems. Center for Resource Solutions. March.



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