The Environmental Protection Agency (EPA) and the Department of Transportation submitted their draft final rule on limiting greenhouse gas (GHG) emissions from cars and light duty vehicles to the White House for review on March 9th. The fleet-wide ruling would require passenger cars, light-duty trucks, and medium-duty passenger vehicles to meet an estimated combined average emissions level of 250 grams of carbon dioxide per mile, or the equivalent of a 35.5 miles per gallon (MPG) fuel economy standard by 2016. Requirements would take effect beginning with the 2012 model year, and increase in stringency until the full standard would be met in 2016.

The draft final rule follows a joint Notice of Intent released by the EPA and Department of Transportation in May 2009, indicating that the two agencies would work together to establish national vehicle GHG and fuel economy standards for new cars and trucks sold in the United States. It is supported by energy legislation passed by Congress in 2007 mandating a fuel economy of 35 MPG by 2020, as well a 2007 Supreme Court ruling giving the EPA authority to regulate GHGs from vehicles under the Clean Air Act, contingent on its finding that GHG emissions from vehicles endanger public health and welfare (Dec. 2009).

A resolution tabled in the Senate seeks to repeal the EPA’s authority to regulate GHGs. If successful, regulation limiting GHG emissions from vehicles could not be enacted (see related article Bumpy Road Ahead to EPA Regulation). A final ruling is expected to be filed by the EPA at the end of March.

By Eva Berton, .(JavaScript must be enabled to view this email address)