Gasoline Alternatives Back In The News
by Bob Hagin
June 25, 2001
They say that what goes around, comes around and the latest subject of this axiom is the assumed need for something to fuel our vehicles besides straight gasoline. Opponents of this venerated liquid state that it burns "dirty," pollutes our air and is adding to the greenhouse problem that's warming our universal atmosphere and will soon lead to the melting of our polar ice caps. Proponents of gasoline as an automotive fuel contend that it's relatively cheap, there's enough of it to fill our needs and that our personal vehicles are built for it.
Vehicular pollution caused by gasoline is again center-stage and the crusade is the need for something to mix with it to make it burn "cleaner." For a while it was felt that MTBE (methyl tertiary butyl ether) and other fuel oxygenates added in small amounts would cut down on auto pollution and help save the world. Unfortunately after a few years of use in California gasolines, it was determined that MTBE was getting into the ground water and contaminating what we drink. Now it's become a pollution problem itself.
The federal government in the form of the George Bush administration is now calling for ethanol as an gasoline additive to "...help reduce ozone-forming emissions, particulates and nitrogen oxides from gasoline," according to the website of Central Minnesota Ethanol Co-op. Ethanol is, of course, a more genteel name for the drinkable alcohol you'll find in your favorite adult beverage. Gasoline can be cut with 10-percent "neat" (almost pure) ethanol and the mixture is a perfectly acceptable fuel, although it produces a bit less power than straight gasoline. The advantages of ethanol as an additive are that it's renewable and the residue after the "mash" is fermented can be sold as cattle feed. Another advantage is that it's a money-maker for corn and grain growers. The Washington lobbying going on for the mandatory use of ethanol is very strong and involves lots of "contribution" money.
But also in the fight for approval and support from the government as a fuel additive is methanol or as us old-timers refer to it, wood-alcohol. Chemically, it's the "evil twin" of ethanol and is very poisonous. It used to be made by distilling wood chips (hence its name since the 17th century) but the more modern method is through a catalytic breakdown of natural gas and steam. It too can be used in a 10-percent mix with gasoline but in some cases, the methanol in the mix (called M85 in the auto industry) has been known to cause some corrosion in engine parts unless the car or truck is designed for it. GM makes vehicles that are especially prepared for M85. In a paper on the subject of ethanol, (the alleged "good twin") in gasoline, the American Methanol Institute claims that rather than decreasing vehicle emissions they are increased by use of ethanol. The struggle boils down to the question of credibility.
As an aside, methanol is used in the production of MTBE as well as the energy source for futuristic "fuel cell" technology that's getting lots of media coverage these days.
As a stand-alone fuel, methanol has been used in oval-track race such as those that run in the Indy 500 since just after World War I. Unused fuel is immediately removed from cars after a race for a variety of reasons including its corrosiveness.
Also a contender for the Alternate Automotive Fuel Crown is compressed natural gas (CNG), the same vapor that piped into many suburban and urban homes for cooking and heating. It's odorless (at least until the gas companies add a distinctive "warning" odor so that a leak can be detected by the homedweller), and very clean burning. In an internal combustion engine, CNG burns so clean that after many hundreds of thousands of hours of daily use, CNG engines show no carbon buildup or oil contamination at tear-down time. In a vehicle, CNG is pumped into a heavy, high-pressure tank that's usually located in the same cavity that traditionally holds the gas tank. Many police departments, taxi fleets, bus systems, indoor fork-lift trucks and, of course, gas company fleets have been converted to CNG.
And while CNG has many attributes for fleet use, for individual "private" transportation, its use is not only difficult but borders on being impossible. An economical "fill-up" at the rare CNG depot is an overnight affair while a quick-fill is more speedy but more expensive. Private parties can get their vehicles converted readily enough but the automakers who build CNG-specific vehicles will only sell to commercial and industrial fleets. Home-fills are possible with some pretty expensive equipment but the various tax collectors try to make sure that natural gas used in cars and trucks generate fuel tax revenue.
There are other fuels that could and are used to power internal combustion engines including propane, liquefied natural gas and even the spent frying oil from the cooking french fries in fast food restaurants.
But as I look out of the window of my office, I see the real reason why gasoline will remain our chief source of energy in personal transportation for a long time. Close at hand is a multi-billion dollar oil refinery complex whose owners are very unwilling to see their investments and incomes jeopardized by "newcomers." Additives? OK - but "replacement," that's a fighting word.