Why focus on the fuel economy of cars and light trucks?
These vehicles account for about 40 percent of all U.S. oil consumption. As a nation, we substantially improved our fuel economy in the late 1970s and early 1980s. However, our average fleet fuel economy actually started to decrease by the early 2000s with the popularity of sport utility vehicles and trucks. Why address greenhouse gases? Cars and light trucks currently emit about 16% of our total greenhouse gas emissions. Under the new rule, cars and trucks will release less of the greenhouse gas carbon dioxide (CO2) by using gasoline more sparingly. Other potent greenhouse gases like methane, nitrous oxide, and hydroflourocarbons (i.e., air conditioning gases) will drop too. Fuel economy has been regulated for decades, but the authority to regulate greenhouse gases under the Clean Air Act was not confirmed until the 2007 Massachusetts v EPA US Supreme Court decision. [exit DNR] What will the new rule require? Manufacturers of passenger cars, light-duty trucks, and medium-duty passenge
