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Ethanol

Alternative Fuels Pump

Ethanol is an alcohol-based fuel made by fermenting and distilling starch crops, such as corn. It can also be made from "cellulosic biomass" such as trees and grasses. The use of ethanol can reduce our dependence upon foreign oil and reduce greenhouse gas emissions.

E10 (gasohol)

E10 (also called “gasohol”) is a blend of 10% ethanol and 90% gasoline sold in many parts of the country. All auto manufacturers approve the use of blends of 10% ethanol or less in their gasoline vehicles. However, vehicles will typically go 3–4% fewer miles per gallon on E10 than on straight gasoline.1

E85

E85, a blend of 85% ethanol and 15% gasoline, can be used in flexible fuel vehicles (FFVs), which are specially designed to run on gasoline, E85, or any mixture of the two. FFVs are offered by several vehicle manufacturers. To determine if your vehicle can use E85, consult your owner’s manual or check the inside of your car's fuel filler door for an identification sticker.

Cost. Cost varies regionally. It is cheaper than gasoline in some areas, such as the Midwest, and more expensive in others.

Availability. More than two thousand filling stations in the U.S. sell E85, and that number is increasing rapidly. Visit the Alternative Fueling Station Locator for locations of service stations selling E85.

Performance. No noticeable difference in vehicle performance when E85 is used.

MPG. FFVs operating on E85 usually experience a 25–30% drop in miles per gallon due to ethanol’s lower energy content.2

Advantages & Disadvantages of E85
Advantages Disadvantages
  • Domestically produced, reducing use of imported petroleum
  • Lower emissions of air pollutants
  • More resistant to engine knock
  • Added vehicle cost is very small
  • Can only be used in flex-fuel vehicles
  • Lower energy content, resulting in fewer miles per gallon
  • Limited availability
  • Currently expensive to produce

MotorWeek Videos

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Ethanol Videos

More Information

Fuel Economy Information for Ethanol Flexible Fuel Vehicles - Find a Car

Alternative Fuels and Advanced Vehicles Data Center (U.S. Department of Energy)

Data Sources

1. Knoll, Keith, Brian West, Wendy Clark, Ronald Graves, John Orban, Steve Przesmitzki, and Timothy Theiss. 2009. Effects of Intermediate Ethanol Blends on Legacy Vehicles and Small Non-Road Engines, Report 1 – UpdatedAdobe Acrobat Icon. NREL/TP-540-43543. National Renewable Energy Laboratory, Golden, Colorado, p. 3-3.

2. West, Brian H., Alberto J. Lopez, Timothy J. Theiss, Ronald L. Graves, John M. Storey, and Samuel A. Lewis. 2007. Fuel Economy and Emissions of the Ethanol-Optimized Saab 9-5 Biopower. SAE Technical Paper 2007-01-3994.