Fuels, Alternative

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FUELS, ALTERNATIVE

FUELS, ALTERNATIVE. The phrase "alternative fuels" is usually used to mean fuels for motor vehicles that are not gasoline. Alternative fuels can also refer to any fuel that is not a fossil fuel. Sometimes the phrase is used inaccurately to refer to alternative sources of energy or power, for example, hydroelectric dams and geothermal power plants. The search for alternative fuels has a long history in the United States. For instance, the Stanley Steamer automobile, unlike cars with internal combustion engines, could be powered with several different fuels: gasoline, raw petroleum, coal, charcoal, oil, and wood. By the mid-1920s, however, the Stanley Steamer was no longer manufactured, and gasoline was the fuel of choice for motor vehicles.

Smog created by the burning of coal, gasoline, and other petroleum derivatives created serious health hazards in American cities by the 1940s, and thereafter caused environmental damage even in remote wilderness areas by poisoning trees and other wildlife. By the 1970s, acid rain was a significant presence and poison in the nation's waters. Individual states and the federal government began enacting laws intended to limit and eventually end air pollution. By the 1980s, manufacturers of motor vehicle engines were in a bind, because they were simultaneously required by law to lower the pollution of their fuels while increasing the mileage per gallon of their engines. Ethanol-powered vehicles were introduced for public sale in 1992 in an effort to meet the regulations of the 1990 Clean Air Act. Their fuel was a blend of 85 percent ethanol and 15 percent gasoline. Ethanol was made at first from corn but eventually many plants were used; by 2000, ethanol was generating about $5 billion per year in revenue for farmers. When the fuel additive MTBE was found to be very toxic to humans and a pollutant of water supplies, manufacturers began replacing it with ethanol, beginning with Getty Oil in 1999.

Automobile manufacturers also experimented with vehicles powered by electricity; their range was too limited, at first, and recharging them was difficult. By 2001, however, California cities were installing recharging stations in public parking lots in an attempt to comply with California laws requiring electric vehicles be available to consumers. Chrysler, Ford, General Motors, Honda, Mazda, Nissan, Toyota, Shell, and Solectra all offered assembly-line vehicles with electric engines by 2000, with the Nissan Atra EV meeting with early popular success. By 2002, manufacturers were experimenting with fuel cells that use hydrogen, thus increasing the distance a vehicle could travel on one charge. Chrysler took an early lead in the use of fuel cells with its NECAR 4, but motor vehicles powered by fuel cells were still primarily experimental in 2002.

To meet the requirements of antipollution laws, manufacturers also worked with "biodiesel,"—an alternative to traditional diesel fuel that is derived from vegetable oil. Biodiesel fuel pollutes far less than diesel oil but requires engines to be remanufactured to adjust for a different compression force. By 1999, Arizona, California, Nevada, and Utah were working on creating fuel stations for trucks that used biodiesel. A rival to biodiesel is dimethyl ether, which contains far fewer contaminants than diesel and biodiesel fuels. However, it requires methanol in its mix and by 2002 was too hard to produce on a scale large enough to meet the needs of trucks and other diesel-powered vehicles.

Methanol, derived from natural gas, has found favor with American motor vehicle manufacturers. Usually used in a mix of 85 percent methanol and 15 percent gasoline, its drawbacks include difficulty in starting cold engines and difficulty in mixing consistently with oxygen when in use. Compressed natural gas has become a popular alternative to gasoline, especially in large vehicles such as busses. A significant drawback to compressed natural gas is its expense—some bus companies and other transportation firms need government subsidies to pay for it. Even so, it pollutes far less than gasoline. In 1999, Syntroleum, in partnership with Chrysler, began working on trapping and cleaning (primarily a matter of removing sulfur) "waste" natural gas that is usually burned off at oil wells. An alternative use for natural gas is synthetic fuel, which produces hydrogen that could be used to power vehicles or in fuel cells.

Supposedly free of most pollutants, methane is a potentially an enormous source of fuel. Using methane presents technological problems, however. Manufacturers have not yet determined how to harvest enough methane to make its sale profitable. Propane, popular for heating homes, is easy for consumers to buy. Its weaknesses include difficulty in starting an engine and keeping a motor vehicle at highway speeds.