Cap-and-trade is a market-based way to reduce pollution. It was first used successfully in the U.S. in the 1990’s, under former President George H.W. Bush to reduce sulfur dioxide, which causes acid rain.
Around the world,Ā more than 40 governments, in an effort to combat climate change, have put some sort of price on carbonāeither by directly taxing fossil fuels, implementing cap-and-trade, or doing both. In the U.S., cap-and-trade systems are in place in California, and in the Northeast.
Pennsylvania is currently studying a citizen-led petition to implement an economy wide cap-and-trade system, modeled on California’s.
Here’s a brief explainer:
The Environmental Quality Board voted Tuesday to approve a draft regulation that would have Pennsylvania join RGGI. It next goes up for public comment.
By
Rachel McDevitt 
House Bill 2025 would require legislative approval for Pennsylvania to enter a program such as the Regional Greenhouse Gas Initiative.
By
Rachel McDevitt 
The bill would bar the Department of Environmental Protection from taking any action that is designed to control carbon dioxide emissions, including participation in a regional greenhouse gas cap-and-trade program such as RGGI, unless the action is authorized by the General Assembly.Ā Ā
Pennsylvania may soon join a regional program meant to limit greenhouse gas emissions and increase investments in green transportation.
By
Kathleen Davis/WESA 
By
Scott Blanchard 
The bill would allow Pennsylvania to set its own cap, or negotiate with a group of other states in a regional program.
By
Dana Bate/WHYY 
The organization is trying to walk a fine line between respecting statesā rights while figuring out how to incorporate diverse climate polices into its wholesale electricity market.
The ramifications of the petition could be politically significant– allowing significant climate policy to be implemented without new legislation.
Dozens of groups including environmental organizations, legal scholars, churches, and local governments argue Pennsylvania has the legal authority and constitutional duty to act on climate change.
