Flex-Fuel Dilemma: Fill 'er up with Gasoline or Ethanol?

By KBB.com Editors on July 10, 2001 8:05 PM

If you own a flex-fuel vehicle the personal decision to fill your vehicle's fuel tank with gasoline or E85 (a mix consisting of 85-percent ethanol and 15-percent gasoline) involves some value choices and financial trade-offs. Do you want to show your concern for the environment? Are you worried about the cost? Is driving range to your next stop important?

Those are the personal issues. Your everyday decision might be a very different one, and is often no decision at all. Currently there are about 1,400 fueling stations offering E85, most of them clustered in the Midwest. There are only 11 states that have 50 or more E85 stations and over half the states have 20 or fewer -- most small towns will have that many gas stations. Furthermore, many of those "fueling stations" are private or for government-vehicle use only, so you couldn't really pull up at the pump even if you wanted. So if your everyday reality is you can't buy it in the first place, the personal decision is irrelevant.

One major advantage claimed by the proponents of E85 is that it helps us move further away from dependence on foreign oil. If so, that movement isn't very far; some estimates are that current ethanol use may be moving us no more than a very few percentage points away from foreign oil dependence, if at all. According to the EPA, E85 currently accounts for less than three percent of the gasoline market. The EPA also says that "ethanol and other biofuels could replace 30 percent or more of U.S. gasoline demand by 2030," but "other biofuels" will be a considerable part of that. And, according to the National Ethanol Vehicle Coalition (NEVC), which on its website bills itself as the nation's primary advocate for expanded use of E85, "If every kernel of corn (grown in this country) was used solely for refining E85," it would replace 24 percent of foreign oil used for gasoline. But that's not going to happen, since corn is a basic feed substance for cattle, hogs, chickens, turkeys and whatever else, and it's also a fundamental sweetener in the form of corn syrup. Corn is in beef, milk, butter, cheese, pork, deli sandwiches, Thanksgiving dinners, breakfast cereal, soda pop, taco shells and popcorn at the movies. Thus, there is no shortage of opponents of E85 who readily point out that the impact on our environment, higher worldwide food prices and the energy and water needed to produce corn-derived E85 far outweigh the advantages.

Here are some relevant points: The recent drastic development and investment in ethanol and its production have driven up the price of corn around the world. This is causing some profound changes in agriculture. As to the issue of the production of ethanol requiring more energy than the ethanol has in it when the process is complete, the NEVC says that "has been a common misconception of the ethanol industry" and claims a "38-percent gain in the overall energy input/output equation for the corn-to-ethanol process." But a study done by researchers at the University of California, Berkeley, said that the cumulative energy consumed in corn farming and ethanol production is six times greater than the energy the ethanol provides in the car engine. According to Tad Patzek, the professor who led the study, "We're embarking on one of the most misguided public-policy decisions to be made in recent history," and one of the participating students, Jason Lee, said "It's ridiculous to think it would decrease our dependence on oil."

One conclusion of the Cal Berkeley study was that the energy input of 4.93 gallons of gasoline equivalent (to produce the ethanol) results, disappointingly, in an energy output of 1.74 gallons of gasoline equivalent from the ethanol produced or a net energy loss of 65 percent. Another study, conducted by David Pimental of Cornell University, calculated that running an average American car for one year on corn-based ethanol blended with gasoline would require 11 acres of farmland or the same area needed to grow a year's worth of food for seven people. Pimental concluded that "Abusing our precious croplands to grow corn for an energy-inefficient process that yields low-grade automobile fuels amounts to unsustainable subsidized food burning."

There are also differences of opinion regarding how it operates in a car's engine. Some sources claim that ethanol-fueled vehicles make more power, which requires some explanation. Ethanol has an octane rating of 113, so mixing it into gasoline increases the octane rating of the blend. This would allow the engine to be designed and built with a higher compression ratio and to be tuned with more spark advance, both of which would increase power output. So it's not exactly true that ethanol delivers "more power," but building and tuning engines to take advantage of ethanol's higher octane could result in more power.

The truth is that ethanol has much less energy by volume than gasoline, so using E85 in the vehicle will result in significantly higher fuel consumption. Again, there are differences of viewpoint and presentations of facts. The NEVC says vehicles running on E85 "experience a 10 to 15-percent drop in fuel economy." But, according to the EPA's own official mileage estimates, the differences are much greater, with typical fuel-economy penalties for ethanol in flex-fuel vehicles in the range of 25 to 30 percent.

The U.S. Department of Energy (www.fueleconomy.gov) states E85 has about 27-percent less energy than gasoline. The same report says that while you pay a little more for E85 fuel, by using it you help reduce the consumption of petroleum and therefore reduce our dependence on foreign oil.

The Department of Energy's website allows easy comparisons of fuel costs of various flex-fuel vehicles operating on either E85 or gasoline. The problem is that, currently, fuel costs are changing so rapidly that what was valid yesterday is useless tomorrow. But it also gives information about various vehicles' carbon footprints, which would not change based upon price. According to the comparison chart, running a 2008 Chrysler Sebring solely on E85 for one year would reduce carbon dioxide emissions by about 2,800 pounds, while driving a GMC Yukon XL on E85 for one year would reduce carbon dioxide by about 4,400 pounds.

One factor weighing heavily on consumers' minds is the price per gallon, particularly when gasoline has passed four dollars per gallon and seems headed for five. It's difficult to get good information on such a moving target, but E85 seems to be roughly 25-percent less at the pump than gasoline as this is being written. However, as we pointed out earlier, the availability is spotty at best, unless you live in the corn belt of the Midwest, and prices vary even more widely than do gasoline prices. Besides, you can't travel as far on a gallon of E85, so if the tank's empty you have to take what you can find.

This limited availability is one reason vehicle manufacturers point out to owners that they can mix gasoline or E85 in any combination. The fuels are completely compatible and mix well, and that convenience of the flex-fuel vehicle is a plus. Another plus is that E85 is biodegradable, so spilling it doesn't pose the same issues as running gasoline down a storm drain.

Ethanol was once seen as a kind of easily renewable fuel source that would cure a world of environmental ills and we could grow oodles of it right here in America's heartland and not have to depend on foreign oil. There are numerous indications that none of that is turning out to be true, at least in the current environment when the bulk of our ethanol comes from corn. About all you can say for sure is that, once you have it, burning E85 in the engine of a flex-fuel vehicle will dump less carbon dioxide into the air, and you'll have to stop more often to fill up the tank. All the rest is still being debated.