Fuel producers refine ethanol from 100 percent pure-grain alcohol. Although ethanol helps the world meet its commitment to pollution reductions, ethanol also decreases the gas mileage a person gets from their car.
Ethanol usually gets mixed into gasoline, with concentrations usually not going past 85 percent, called E85. Ethanol's effect on a car's fuel efficiency depends on the blend that the person uses. E85, for instance, reduces fuel economy by 7 to 8 miles per gallon when compared to gasoline, according to the Environmental Protection Agency.
Ethanol has 34 percent less energy than gasoline per gallon, which equates to about 2 to 3 miles per gallon for E10 (10 percent ethanol), according to the New York Times.
Many fuel stations put ethanol in gasoline automatically due to a U.S. law that demands 36 billion gallons of alternative fuel be made available in the United States by 2022.
Consumers who do not wish to use any amount of ethanol in their vehicle should look for gas stations that claim to sell only 100 percent pure gasoline.
Consumers who do want ethanol in their fuel can counteract the effects of this additive by practicing better driving habits. Cars should stay between 40 and 60 miles per hour for optimum fuel usage and use cruise control to keep the vehicle going at a constant speed, according to Edmunds.com.
