The effort isn’t unprecedented: California already has a plan to curb transportation emissions, and many East Coast states are members of the Regional Greenhouse Gas Initiative (RGGI). Since 2009, the initiative known as “Reggie” has capped the overall carbon dioxide produced by power plants and required plant operators to buy permits for their emissions.

Power plant emissions have fallen by 51 percent in the region since the program began, according to an analysis of RGGI data by the Acadia Center, an environmental nonprofit with offices in five Northeast states. States have used the permit proceeds to weatherize homes and to give consumers rebates on their electric bills. But the region faces significant hurdles in replicating that reduction with transportation emissions.

Read the full article from Stateline here.