​​​​Maryland is committed to finding real bipartisan, common sense solutions to protect our environment, combat climate change, and improve our air quality. By working together, we are showing that it is possible to find consensus to protect our natural resources, promote clean energy, and grow our economy for current and future generations.
Governor Larry Hogan
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Regional Greenhouse Gas Initiative (RGGI) in Maryland

RGGI Updates

  • On December 17, 2018, the New Jersey Department of Environmental Protection made public a draft proposed regulation to reduce greenhouse gases from the electricity sector, which was open for public comment from December 17, 2018 to February 15, 2019.  In developing this rule, New Jersey has taken an important step towards resuming participation in the RGGI program.  Maryland and the other RGGI participating states continue conversations with New Jersey as its state-specific process for the rule moves forward, including the gathering of stakeholder input.

  • ​​On February 21, 2019, the RGGI participating states submitted joint comments to Virginia regarding the compatibility of Virginia's re-proposed regulation with the RGGI participating states' existing 2017 Model Rule.  As Virginia continues to refine its re-proposed rule, the RGGI participating states will continue to engage in discussions with and provide assistance to Virginia as its state-specific process continues.

RGGI in Maryland


Science has demonstrated with a high degree of certainty that Earth's climate is being altered by human activities, principally by the emission of heat-trapping greenhouse gases (GHGs), such as carbon dioxide (CO2), into the atmosphere.1 According to the 2014 Report of the Intergovernmental Panel on Climate Change (IPCC), "effective adaptation and mitigation responses will depend on policies and measures across multiple scales: international, regional, national and sub-national".2

The actions Maryland takes to mitigate climate change at the state level are integral to protecting the future and prosperity of not only the state of Maryland but also the United States of America and the global community to which it belongs.

The RGGI Program is a central component of Maryland's GHG reduction strategy. As the first program of its kind in the United States, RGGI serves as a model and inspiration to other states and regions to either participate in RGGI or implement their own regional CO2 trading initiatives.

Program Overview

RGGI is a cooperative effort by nine northeast and mid-Atlantic states to reduce CO2 emissions generated by fossil fuel-fired power plants while benefiting the regional economy. Guiding the program are the shared commitments to reducing CO2 and allowing flexibility and autonomy among the states. Maryland has participated in RGGI since 2007. Other states currently participating are Connecticut, Delaware, Maine, Massachusetts, New Hampshire, New York, Rhode Island, and Vermont.

RGGI is structured as a "cap and invest" program, with a regional cap or limit on CO2 emissions that declines by a certain amount annually. The states establish individual emission budgets, which they distribute as "allowances" permitting the holder to emit one short ton (2,000 lbs.) of CO2 per allowance. The regional cap consists of the sum of the states' emission budgets. Each state participating in the regional initiative has developed its own program and regulations based on the blueprint provided by the RGGI Model Rule. States sell a majority of emission allowances at regional quarterly auctions, and auction proceeds fund various state and local programs which promote energy efficiency, renewable energy, bill assistance, or other consumer benefits.

Last year, the participating states reached consensus on a series of improvements to the program. The Model Rule contains four major improvements:

  1. Reduce the emissions cap by an additional 30% from 2020 to 2030;
  2. Add the innovative new Emissions Containment Reserve, which will reduce emissions, even more, when it is inexpensive to do so;
  3. Adjust for the allowance bank remaining at the end of 2020; and
  4. Improve and maintain the Cost Containment Reserve, which is an important element to manage compliance costs.

Upcoming stakeholder meetings may be found on the MDE calendar and the RGGI website.

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1Maryland Commission on Climate Change Scientific and Technical Working Group, 2015. Appendix 1 of 2015 Maryland Commission on Climate Change Report. "Reducing Emissions of Greenhouse Gases Beyond 2020".
2Intergovernmental Panel on Climate Change, 2014. Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, R.K. Pachauri and L.A. Meyer (eds.)]. IPCC, Geneva, Switzerland, 151 pp.