Ethanol Myths

1. Ethanol is very rarely used in American cars.

Most likely, you're using ethanol in your car without even knowing it. In many regions, small amounts of ethanol are blended with gasoline to reduce emissions. Mixtures as high as E10 (10 percent ethanol and 90 percent gasoline) are safe for use in most vehicles.

Much of the news lately has been about fuel blends that have higher ethanol content. The most common is E85 (85 percent ethanol and 15 percent gasoline), which only can be used in vehicles that are designed for that fuel.

2. Using ethanol will eliminate global warming.

One might expect that by using E85, net carbon dioxide emissions would be almost zero. The crops used to make the ethanol absorb CO2 from the atmosphere during their growth, then this CO2 is put back into the atmosphere when the ethanol is burned in an automobile engine. In reality, this cycle is overly simplistic because it fails to recognize other greenhouse gas emissions that occur during the cultivation and production of ethanol. Modern farming, for example, relies heavily on diesel-powered equipment that emits greenhouse gases. Distilling ethanol is also an energy-intensive process that often uses electricity generated from coal, another source of greenhouse emissions.

Researchers at the University of California at Berkeley recently examined six major studies of ethanol production and concluded that using ethanol made from corn instead of gasoline would lead to a moderate 13 percent reduction in greenhouse emissions. However, the researchers note that more dramatic reductions are possible if technology advances make it economical to make ethanol from cellulosic materials such as switchgrass, a crop currently grown by some U.S. farmers to control erosion on idle fields. Using cellulosic ethanol, they project, could result in 88 percent less greenhouse gas emissions.

The UC Berkeley study also contradicts a common criticism of ethanol: that it takes more energy to produce it than it delivers as a motor fuel. The study concludes that ethanol made from corn does indeed have a positive "net energy balance," particularly if you consider that other valuable products, such as corn oil, are byproducts of the ethanol-making process.

3. Ethanol is cheaper than gasoline.

Data on fuel prices from the Department of Energy shows that in the Midwest-where much of the country's ethanol is produced-E85 sells for nearly 30 cents less per gallon than conventional gasoline. However, on the West Coast, filling up with ethanol would cost a driver 35 cents more per gallon. In the mid-Atlantic states, E85 had an even higher premium: 44 cents per gallon.

The higher price of E85 in many areas is made worse by another of ethanol's drawbacks: ethanol, regardless of the price you pay for it, contains less energy than gasoline. This means that your car won't go as far on a gallon of E85, and your fuel economy will decrease by 20-30 percent. This is bad news for consumers because even if the price of E85 at the pump is cheaper than gasoline, using ethanol may not be less expensive in the end.

4. Ethanol-ready vehicles are equally available in all sizes.

If you're looking for small, fuel-efficient vehicles that use E85, you may be disappointed. Half of the 2006 flexible-fuel vehicles are full-sized pickups or SUVs, including the Dodge Durango (rated at 12 mpg in the city and 15 mpg on the highway).

With minor changes and expense, DaimlerChrylser can make the Dodge Durango compatible for E85 fuel. As a result, the E85 Durango can be rated for 23 mpg-instead of the 13 mpg rating for the conventional Durango -even if its owners never use E85 fuel.

Automakers' tendency to make their largest vehicles E85 compatible is rooted in America's fuel economy rules. Since 1988, automakers have been allowed to assign flexible-fuel vehicles higher fuel economy ratings under the government's CAFE fuel economy regulations. This means that a vehicle like the Durango, which averages 13 mpg would be rated at roughly 23 mpg for CAFE purposes, even if its owner never fueled it with E85.

In fact, very few flex-fuel vehicles are using E85, largely because it's not widely available. The DOE lists more than 600 E85 stations in the United States, but nearly half of those are in two states: Minnesota and Illinois. Other areas, even populous ones, have little E85 infrastructure. For example, New York, California, Texas and Florida have just 15 E85 stations combined, only two of which allow sales to the general public.