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A Driving Force David Holzman Abstract
Alternative fueled vehicles have long been the dream of many scientists. To date, impractical fuel systems, underwhelming mileage rates, and whopping purchase prices have effected a lukewarm reception to such vehicles. But the technology appears to be heating up.
Fuel cells, cleaner gasoline, diesel engines, internal combustion/electric hybrids, Stirling engines, and battery packs are all candidates for alternative fueling. Many of these fuels were once considered impractical for use in automobiles. But recent advances have made engines that were designed to power spacecraft small enough and light enough to fit in a car.
Meanwhile, reducing the weight of cars is a major goal. One principle of alternative fueled vehicles is that major reductions in body mass lead to other reductions in mass–for example, smaller motors and smaller brakes–to the point that ancillary systems such as power steering and power brakes become superfluous. The use of advanced composite materials in place of steel can reduce a car's mass by 50–67%.
Why develop alternative fuels and vehicles? The two primary answers are the cost of importing oil and the need to reduce air pollution. Alternative fuels would ideally increase fuel mileage at least 5-fold, to over 125 miles per gallon, though some claim that 300 mpg is possible. In addition, reduction in carbon dioxide emissions would be proportional to–or better than–fuel mileage improvement, depending on the motive technology: CO2 emissions could drop as much as 100-fold with some technologies.
Detractors argue that alternative fuel proponents don't understand the complexities of creating a workable engine design. But probably the most intractable obstacle to developing alternative fuels and vehicles is the lack of a market infrastructure, because it is the one problem that may require a political rather than a technological solution.
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