MTBE or Ethanol or ?

Over the past few months a relatively quiet debate has been ongoing in Washington. The result of this debate will be very significant for air and water quality as well as for the price of gasoline.

The issue is which fuel additive will be used in gasoline sold in the most polluted areas of the country: MTBE, which has been used for a number of years now as a result of federal clean air legislation passed by Congress a decade ago, or ethanol, whose principal producer is agribusiness giant Archer Daniels Midland (ADM).

In March, Carol Browner of the Environmental Protection Agency (EPA) announced plans to phase out the use of MTBE, which has about 80 percent of the $4.5 billion market for so-called “reformulated gas.” Reformulated gas is supposed to burn cleaner than normal gasoline because it is “oxygenated” and therefore produces less toxic emissions.

The problem with MTBE (methyl tertiary butyl ether) is that it has been leaking from underground storage tanks and contaminated water supplies in 31 states. In addition, water-well owners in 16 states filed a class-action lawsuit against some of the biggest oil companies saying that they have long known about MTBE’s hazards. Besides the leakage problem, people have also complained about getting headaches and other symptoms by using MTBE gas in their cars.

Browner said that MTBE should be at least partly replaced with ethanol-alcohol distilled from corn, which is supposed to be safer and “renewable.” If that happens, according to Andrew Fairbanks, an energy industry analyst at Merrill Lynch, gasoline prices would increase by three to five cents. Naturally, senators from the corn-belt states are highly enthusiastic, as is Vice-President Gore and George W. Bush—they both want votes from those areas.

Obviously, with a legal onslaught in the works, MTBE is on its way out. But is ethanol any better? The weight of scientific evidence has shown that neither MTBE nor ethanol benefits air quality, and both cause serious damage to the environment.

As said before, the purpose of oxygenated gas is to decrease carbon monoxide emissions thus increasing the amount of oxygen emitted. If this fuel was used in cars built during the 1970s and 1980s, the results would have been cleaner tailpipe emissions. However, today, through the use of computer controls, oxygen sensors and catalytic converters, there is little if any measurable benefit by using ethanol blended gas over normal gas.

In addition:

• It takes almost as much energy to produce ethanol as the ethanol itself can generate—76 BTUs of energy to produce 100 BTUs of ethanol. Automobile engines are only about 20 percent efficient, so if 100 BTUs of ethanol are in your gas tank, you’ll only get 20 BTUs of usable energy. In addition, the energy used to manufacture ethanol comes from primarily fossil fuels (coal, oil) which add to the atmosphere the pollutants that ethanol is supposed to reduce.

• It takes more reformulated gasoline to equal normal gasoline. In other words, oxygenated gasoline reduces gas mileage by 2.3-3.5 percent.

• Ethanol is a very caustic substance. It dries out and destroys your car’s fuel system’s o-rings and gaskets and also damages those electronic components, such as fuel-injectors, it comes into contact with. While this is more prevalent in older cars, new cars can still be damaged. And according to a 1997 study conducted by Argonne National Laboratory, the burning of ethanol-blended fuel leads to increased levels of toxins (e.g. aldehydes and peroxyacyl nitrates). This is a new group of toxins that little is known about.

Yet, in the last ten years, since the passage of the Clean Air Act, tailpipe emissions have been drastically reduced—but this was not due to oxygenated gasoline. The oil companies were required by the act to reduce emissions, and since oxygenated gas didn’t do the job, they found other ways to do it. They adjusted the aromatics, sulfur content and vapor pressure of gasoline. The result has been that tailpipe emissions have fallen to levels below what was called for in the 1990 reformulated gas amendment.

Still, the oxygenate requirement in the act makes it harder and more expensive for refiners to reduce toxic emissions. What the EPA wants to do is substitute the unneeded MTBE with an equally unneeded ethanol. Two California lawmakers, Democratic Senator Dianne Feinstein and Republican Representative Brian Bilbray, have proposed another solution. They have introduced a bill that would eliminate using oxygenated fuels, but that would still require oil companies to meet lowered emission standards through other methods. Some environmental groups and most of the big oil companies support the measure—while the ethanol lobby and ADM are against it.

Let’s hope the measure passes.

[Peter C. Sessler is the author of 25 books on cars, published by Motorbooks International, Tab Books, Smithmark Publishers, and HP Books. Some of his titles include “Ford Pickup Red Book,” “Muscle Car Greats,” and “Car Collector’s Handbook.” Publication is pending on his latest book, “Model Car Handbook,” to be published by Scale Sports.]