The Regional Greenhouse Gas Initiative (RGGI, pronounced "Reggie") is the first mandatory market based program in the United States to reduce greenhouse gas emissions. RGGI is a cooperative effort among the states of Connecticut, Delaware, Maine, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Rhode Island, Vermont, and Virginia to cap and reduce carbon dioxide (CO2) emissions from the power sector. RGGI compliance obligations apply to fossil-fueled power plants 25MW and larger within the ten-state region. As of 2020, Pennsylvania is pending RGGI membership with an anticipated start in early 2022.