Ethanol fuel is an alcohol (ethyl alcohol) fuel that can be made from very common renewable materials, such as sugar cane, corn, and cellulose,

and is currently the most widely used alternative to gasoline. Ethanol has long been used in motor fuel, usually as an oxygenate additive or blended with gasoline, because ethanol emits less harmful air pollutants than gasoline does. The standard ethanol fuel is called E85, which is a blend of 85 percent ethanol and 15 percent gasoline. However, ethanol contains less energy per gallon than gasoline, so E85-powered vehicles get roughly 30 percent fewer miles per tankful than equivalent gasoline-powered vehicles. In addition, ethanol's lower fuel economy results in more carbon dioxide (CO2) emissions than a similar gasoline vehicle gives off.

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