emission trading

A coal power plant in Germany. Due to emissions trading, coal may become a less competitive fuel than other options. Emissions trading is a market-oriented approach to controlling pollution by providing economic incentives for reducing the emissions of pollutants. The concept is also known as cap and trade (CAT) or emissions trading scheme (ETS). One prominent example is carbon emission trading for CO2 and other greenhouse gases which is a tool for climate change mitigation. Other schemes include sulfur dioxide and other pollutants.

In an emissions trading scheme, a central authority or governmental body allocates or sells a limited number (a "cap") of permits that allow a discharge of a specific quantity of a specific pollutant over a set time period. Polluters are required to hold permits in amount equal to their emissions. Polluters that want to increase their emissions must buy permits from others willing to sell them.