Ethanol is a renewable fuel made from plants. Essentially non-drinkable grain alcohol, it is produced by fermenting plant sugars. It can be made from corn, sugar cane and other starchy agricultural product. The cellulose in agricultural wastes such as waste woods and corn stalks (cellulosic ethanol) can also be used as a base. In the U.S., most ethanol is currently made from corn, although because of rapidly developing research, cellulosic ethanol may soon become a larger part of the market.
While pure ethanol is rarely used for transportation fuel, there are several ethanol-gasoline blends in use today. E85 is a blend of 85 percent denatured ethanol and 15 percent gasoline. In certain areas, higher percentages of gasoline will be added to E85 during the winter to ensure that vehicles are able to start at very cold temperatures.
E85 cannot be used in a conventional, gasoline-only engine. Vehicles must be specially designed to run on it. The only vehicles currently available to U.S. drivers are known as flex fuel vehicles (FFVs), because they can run on E85, gasoline or any blend of the two. Much like diesel fuel, E85 is available at specially-marked fueling pumps. Today, nearly 700 fueling stations offer it. (Source: EPA / Photo: photosbyjim/iStockphoto)