As of 2014, burning 1 gallon of U.S. gasoline results in 17.68 pounds of CO2, according to the Energy Information Administration. The EIA states that the majority of gasoline contains 10 percent ethanol, and is referred to as E10.
CO2 production from ethanol-free gasoline is higher than E10, at a rate of 19.64 pounds per gallon and 22.38 pounds per gallon for diesel fuel. In addition, biodiesel fuel, or B20, is sold in several states, with 1 gallon producing 17.90 pounds of CO2. Overall, the EIA reports that U.S. gasoline consumption in 2013 produced 1,095 million metric tons of CO2.