What Is E85 Octane Fuel?

by Lexa W. Lee

E85 octane is a fuel blend of 85 percent ethanol and 15 percent gasoline, according to the Renewable Fuels Association. Ethanol is produced from grain, such as corn, in the United States. It has a 105 octane rating.


E85 burns more cleanly than gasoline, producing fewer benzene and hydrocarbon emissions. It also breaks down quickly in water, causing less damage to the environment, according to E85Fuel.com.


E85 is an alternative fuel approved for use in flex-fuel vehicles or FFVs, which can use different blends of ethanol as well as ordinary gasoline. More than 8 million FFVs are on U.S. roads in 2010 -- a number that is steadily increasing each year.

Future Production

Although E85 is produced primarily from corn, research and innovation are moving toward producing ethanol more cheaply from agricultural wastes from rice, sugar cane and wood waste. Such materials require less energy to produce.

About the Author

Lexa W. Lee is a New Orleans-based writer with more than 20 years of experience. She has contributed to "Central Nervous System News" and the "Journal of Naturopathic Medicine," as well as several online publications. Lee holds a Bachelor of Science in biology from Reed College, a naturopathic medical degree from the National College of Naturopathic Medicine and served as a postdoctoral researcher in immunology.