Ethanol 85 or E85 is a fuel which blends up to 85% ethanol with gasoline. This type of fuel can be used in flexible fuel cars which are designed to run on blends of gasoline and ethanol. Use of E85 has been promoted as an alternative to fossil fuels which could reduce dependence on oil-producing nations for energy supplies, although there are some problems with this fuel product which must be addressed. Availability of ethanol 85 varies, depending on where one lives; the American Midwest, for example, has a number of sources for this fuel, while people in Canada may have more trouble getting it.
This fuel has a higher octane rating, which can contribute to increased efficiency. However, pure gasoline may not work effectively in the engine of a flex fuel vehicle which is designed to run on ethanol concentrations as high as 85%, which can be a problem when E85 is not available. Furthermore, like other high octane fuels, ethanol 85 delivers less miles (or kilometers) per gallon (or liter) than other fuels, which means that people can actually end up spending more on fuel with E85 than with conventional gasoline, depending on fuel prices.
This fuel also requires special retrofitting of an engine and its fuel system. Several car companies make flex fuel vehicles which can run on ethanol 85 or other ethanol/gasoline blends, including cars, light trucks, buses, and heavy trucks. In other cases, it may be necessary to convert a vehicle so that it can accept this fuel. Using ethanol 85 in a vehicle which is not equipped for it can have some unpleasant results, including damage to the fuel lines.
Sourcing of ethanol has also been raised as a concern by people who are troubled about the use of ethanol 85. Ethanol is a biofuel, which initially sounds appealing because it is a renewable resource. However, some base materials used for biofuels are very inefficient, and a few types of biomass used for ethanol production are actually so inefficient that more fuel is expended than is produced, and this is a serious problem. Some critics are also concerned about the food versus fuel debate, which centers around the idea that certain countries may be replacing the production of food with the production of fuel.
AGE 85 or aviation grade ethanol 85 is a version of ethanol 85 which is designed for use in aircraft. Aviation fuels need to meet some very specific standards which have made AGE 85 a tough sell to the aviation industry.
By Mary McMahon
Ever since she began contributing to the site several years ago, Mary has embraced the exciting challenge of being a About Mechanics researcher and writer. Mary has a liberal arts degree from Goddard College and spends her free time reading, cooking, and exploring the great outdoors.