How E85 Ethanol Flex Fuel Works

By: Chuck Giametta

E85 Ethanol Flex Fuel Explained

National Ethanol Vehicle Coalition This cycle illustrates how plants, often corn, are turned into ethanol.

Ethanol is an alcohol-based fuel made by fermenting and distilling starch crops, corn mostly. Only a relative handful of renewable energy companies produce it, but virtually all the ethanol they generate comes from renewable crops grown on American farms. On­e acre of corn can be processed into about 330 gallons of combustible ethanol.

Proponents argue that mixing 85 parts ethanol with 15 parts gasoline to create E85 ethanol fuel helps stretch the earth's supply of oil, which is finite. Supporters, such as the Renewable Fuels Association, say E85 ethanol fuel expands the market for U.S. crops and creates jobs in agriculture and refining. By reducing oil imports, backers argue, ethanol eases the nation's trade imbalance and cuts down on the tax dollars and military resources needed to keep foreign oil flowing.


As for environmental benefits, the U.S. Department of Energy says vehicles fueled with E85 ethanol have lower carbon monoxide and carbon dioxide emissions than conventional gasoline or diesel vehicles. Ethanol is water soluble, non-toxic, and biodegradable. E85 ethanol contains far fewer potential contaminants than found in gasoline.

But for nearly every benefit ascribed to E85 ethanol, a detractor is ready with a counterpoint. For example, ethanol production requires burning non-renewable fossil fuels to plant, grow, and harvest the crops and operate refineries. A Cornell University agricultural expert says that, considering the energy costs of growing corn and converting it to ethanol, it takes far more energy to produce ethanol than it yields. (A University of California study, by contrast, insists modern farm efficiency means ethanol generates more energy than it requires to produce.) Critics say ethanol production diverts corn that could be used to feed animals and people, thus shrinking the supply of corn and raising the price of food.

As for environmental concerns, many new ethanol refineries are seeking ways to cut costs by using coal as an energy source. Most now run on natural gas. Coal costs less, but pollutes more. And the U.S. Environmental Protection Agency says that putting more E85 ethanol flex-fuel vehicles on the road will result in more airborne chemicals that create smog, threatening an increase in respiratory ailments.

Detractors also point to burdens on taxpayers. The federal government, along with some agricultural states, has for decades subsidized ethanol production under the banner of farm support. Critics say the main beneficiaries of the billions of dollars in tax exemptions and incentives are giant agribusinesses and corporate refiners. In 2003, Illinois became the first state to remove the sales tax on E85 ethanol fuel. And the federal government provides up to $30,000 in tax credits to gas stations that convert pumps to E85 ethanol fuel.

On the heels of an energy bill signed into law in 2005 that requires refiners to produce more ethanol over the next decade, President Bush has pledged federal dollars to fund additional research into new methods of ethanol production. At the same time, federal regulators anxious to ease administrative burdens on ethanol production have proposed relaxed limits on the amount of air pollution these refineries would be allowed to generate.

This groundswell of support has helped ignite a boom in the number of corn-to-fuel refineries. Some 40 new ethanol-production facilities are expected to come on line by mid-2007. That would bring the national number to slightly over 100, up from just 50 in 1996.

Surprisingly, all this action is directed at what, for now, is a relatively small number of vehicles. Of the roughly 250 million cars, trucks, SUVs, and minivans on America's roads, only about six million are capable of burning E85 ethanol. About half of these E85 ethanol flex-fuel vehicles are in commercial or government fleets.

The majority of private E85 vehicles come from Ford and General Motors, but certain Chrysler, Dodge, Jeep, Mercedes-Benz and Nissan models also are E85 ethanol-compatible. These vehicles have special components installed on the factory assembly line that monitor and compensate for the ethanol/gasoline mix. Their fuel systems are also fortified against the corrosive effects of E85 ethanol.

E85 Throughout the Years

Henry Ford built an ethanol-burning Model T before World War I, and over the years, thousands of fleet vehicles were modified to run on ethanol-based blends. U.S. automakers began making E85 ethanol-compatible components standard on certain models in 1998.

Over the past year, Ford, GM, and DaimlerChrysler have seized the E85 ethanol mantle as a fuel-saving technology and a way to support the environment and promote domestic agriculture. These manufacturers say they plan to put a combined total of 2 million additional E85 ethanol flex-fuel vehicles on the road each year starting in 2007.

They have lobbied Congress for support of E85 ethanol, and GM and Ford help fund campaigns to promote E85 ethanol use and convert gas stations to carry the fuel. GM is even offering owners of its E85 ethanol flex-fuel vehicles who live in Chicago and Minneapolis a $1,000 gas card for E85 ethanol purchases.

For 2007, 29 different models for sale in the U.S. are E85 ethanol flex-fuel capable. That's up from 20 for the 2006 model year. For 2007, GM will offer 17 E85 ethanol flex-fuel models totaling about 400,000 vehicles, compared to nine models in 2006. Ford expects to sell 250,000 E85 ethanol flex-fuel models in 2006.

Still, you'll need to look closely to identify one of these E85 ethanol flex-fuel vehicles. Some early E85 ethanol flex-fuel Fords carry a small road-and-leaf logo and decal reading "FFV," for Flexible Fuel Vehicle. GM identifies its E85 ethanol flex-fuel vehicles with yellow gas caps and "Flex Fuel E85" badges.

­The best ways to determine whether you have an E85 ethanol flex fuel vehicle is to consult your owner's manual or check for an identifying sticker inside the fuel door. A list of E85 ethanol flex fuel-compatible vehicles is also available from several Web sites, ­including and

On the next page, we'll go into more detail about how E85 affects the everyday driver and where this fuel can be found.