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Ethanol Frequently Asked Questions

Questions and Answers about E85 and Flexible Fuel Vehicles

Q: What is Ethanol?
A: Ethanol is alcohol used in transportation fuels. It is a high octane, liquid, renewable fuel, produced by the fermentation of plant sugars. In the United States, ethanol is typically produced from corn and other grain products, although in the future it may be economically produced from other biomass resources such as agricultural and forestry wastes, specially grown energy crops, or even municipal garbage!

Q: What is E85?
A: E85 is the term for motor fuel blends of up to 85 percent ethanol and just 15 percent gasoline. E85 also has a much higher octane (ranging from 100 to 105) than gasoline. It is sold at normal gas stations for use in flexible fuel vehicles and is always labeled so you know when you are pumping it.

Q: Why should I use ethanol?
A: Besides its superior performance characteristics, ethanol burns cleaner than gasoline; it is a completely renewable, domestic, environment friendly fuel that enhances the nation's economy and energy security. Today the U. S. imports more than half of its oil, and overall consumption continues to increase. By supporting ethanol production and use, U.S. drivers can help reverse that trend and keep billions of dollars from leaving the U.S. economy.

85% ethanol can reduce pollution. Government tests have shown that E85 vehicles reduce harmful hydrocarbon and benzene emissions when compared to vehicles running on gasoline.

E85 can also reduce carbon dioxide (CO2), a harmful greenhouse gas and a major contributor to global warming. Although CO2 is released during ethanol production and combustion, it is recaptured as a nutrient to the crops that are used in its production. Unlike fossil fuel combustion, which unlocks carbon that has been stored for millions of years, use of ethanol results in low increases to the carbon cycle.

Ethanol also degrades quickly in water and, therefore, poses much less risk to the environment than an oil or gasoline spill.

Q: What is a flexible fuel vehicle?
A: A flexible fuel vehicle (FFV) is specially designed to run on any ethanol blend up to 85% ethanol. Special onboard diagnostics "read" the fuel blend, enabling drivers to fuel with E85 or gasoline in any combination from a single tank. There are no switches to flip, no mixing or blending. The computer adjusts the FFV's fuel injection and ignition timing to compensate for the different fuel mixtures.

Click here for an abbreviated list of flexible fuel vehicles. If you are unsure that your vehicle is a flexible fuel vehicle, the National Ethanol Vehicle Coalition maintains a flexible fuel vehicle guide on their website at

Q: Will I hurt a gasoline-only vehicle if I use E85?
A: Yes. Longer-term use of E85 in gasoline-only vehicles may cause damage because of the incompatibility of the alcohol fuel with some parts in gasoline-only engines. Performance and emissions will also be compromised.

Q: What happens when E85 is not available?
A: The FFV system allows the driver to use any combination of gasoline or ethanol-from 100 percent unleaded gasoline to 85 percent ethanol. A driver can therefore use unleaded gasoline if ethanol is not available.

Q: How will my car's mileage per gallon change with E85?
A: Ethanol has less energy content than gasoline. Because of this, vehicles may cars experience about a 25% drop in fuel economy. This will vary based on type of vehicle, temperature and driving practices. For comparison purposes, aggressive driving habits can result in a 20% loss of fuel economy and low tire pressure can reduce mileage by 6%.

Q: What are the differences in an FFV compared to a regular gasoline-only model? Are different parts used?
A: There In addition to the fuel sensor that detects the ethanol/gasoline ratio, a number of other parts on the FFV's fuel delivery system are modified so that they are ethanol compatible. The fuel tank, fuel lines, fuel injectors, computer system, anti-siphon device and dashboard gauges have been modified slightly. Alcohols are corrosive, and any part that comes in contact with the fuel has been upgraded to be tolerant to alcohol. Normally, these parts include a stainless steel fuel tank and Teflon lined fuel hoses.

Q: Does an FFV cost more than a gasoline-only model?
A: When manufacturers offer a flexible fuel engine as an option in their vehicles, typically there is no additional cost. In model year 1998, manufacturers began making flexible fuel engines standard equipment on certain makes and models, therefore, no additional cost is incurred. You might be driving an FFV right now and not know it!

Q: Will we deplete human and animal food supplies by using corn and other grains for fuel production?
A: No, actually the production of ethanol from corn uses only the starch of the corn kernel, and all of the valuable protein, minerals and nutrients remain. One bushel of corn produces about 2.7 gallons of ethanol AND 11.4 pounds of gluten feed (20% protein) AND 3 pounds of gluten meal (60% protein) AND 1.6 pounds of corn oil.

Q: Does it take more energy to produce a gallon of ethanol than the energy we get out of it?
A: No. Current research indicates an approximate 38% gain in the overall corn-to-ethanol process and use of that ethanol for fuel. Corn yields and processing technologies have improved significantly over the past 20 years and they continue to do so, making ethanol production less and less energy intensive.

Q: Is E85 more toxic or dangerous than gasoline?
No. 100% ethanol is non-toxic and biodegradable. However E85 contains 15% petroleum gasoline, which is toxic and should be handled the same way as you would handle gasoline.