Alternate Fuels Essay Research Paper Jennifer Allers — страница 2

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magnetohydrodynamic engine that converts the chemical energy of liquid or gaseous fuels into variable-frequency alternating- current electrical power. Nicholaos Pahis of Vernon, Connecticut, has developed a rotary internal combustion engine with an Inherently balanced 8-cylinder design that ingests a constant air/fuel mixture. SSI Corporation of Atkinson, New Hampshire, has developed a computer-controlled engine that operates intermittently, driving a fixed- volume hydraulic pump/motor,” (Lynch 66). An ICE is no longer required to power a vehicle. In the November issue of Popular Science, a fuel delivery system was overviewed; developed by an Italian auto maker, it uses an existing gasoline ICE, but adapts the fuel tank and fueling port to accept propane, methane/natural gas,

and gasoline. The tank can be running low on gasoline, and the car fueled with natural gas or vice versa! Natural gas is an alternative fuel with the added bonus of cleaner and more complete combustion and thus emissions of carbon dioxide and water as opposed to hydrocarbons. Natural Gas: Natural gas does seem a promising alternative. Currently there are an estimated one million natural gas vehicles in service, many of them used by natural gas companies, as city busses, and 250,000 of them used in Italy alone (Birch, 26). A CNG (compressed natural gas) vehicle currently emits less toxic fumes than do gasoline powered vehicles. For comparison, a CNG vehicle emits 8 lb/Yr. “ozone precursors,” (Derr, 31). CNG vehicles are one of the most viable alternative options in the U.S.

due to our country’s enormous supply of natural gas which could power autos for decades to come (Reed, 74). Also, natural gas would be cheaper to purchase than gasoline (Moore, 92). As of 1992, there were an estimated 30,000 NG autos in use in the U.S. (Reed, 74) The natural gas option is certainly not without its drawbacks. The most significant drawback would be a retrofit of existing vehicles with high pressure tanks. Retrofit costs are estimated to be $1500 to $3000 by Gene Moore, a fleet manager in Sacramento, California (Moore, 92). New CNG vehicle cost, detailed by Kenneth Derr, CEO of Chevron, in a speech, and estimated by the the U.S. Department of Energy, is $2500 to $5000 more than a “conventional car,” (Derr, 31). “Natural gas needs to be highly compressed and

requires a special high-pressure fueling station,” (Moore, 92). “Natural gas fuel is stored on the vehicle in either compressed or liquefied form.” CNG autos store at 16 to 25 MPa, and LNG’s (liquefied natural gas vehicles) use pressures of 70 to 210 kPa and -160 ?C (Reed, 74). However, this installation of high pressure fueling stations is not an unrealistic idea; for example, Italy’s countryside is inundated with high pressure natural gas fueling stations for their 250,000 natural gas powered automobiles. Many Italian citizens with CNG vehicles purchase compressors so that they may fuel their vehicles overnight. In the U.S., “natural gas utilities are expanding the infrastructure of delivery systems to make their fuels more available,” (Valenti, 42). Finally, as

required by law, many company fleets are converting or have converted to CNG fleets, proving that the change is indeed possible (Kisiel, 3). This renewable energy approach is feasible. Propane (LPG): Propane, or LPG (liquefied petroleum gas) is one other option similar to CNG but with less viability (due to vehicle manufacturers not for technical reasons). LPG has been used in vehicles since the 1920’s and powers nearly 500,000 vehicles in the U.S. (Moore, 93), over 350,000 vehicles in other countries (Reed, 74). Conversions to LPG powered vehicles peaked in the early 1980’s due to the gasoline price increase, (Reed, 74). Benefits include the potential to reduce CO and hydrocarbon emissions, and the fuel is readily available in regions with natural gas or petroleum refining

industries, (Reed, 74). “There is a substantial infrastructure in place and advanced technologies for storing and dispensing LPG,” (Moore, 93). The cost of storage devices is also less for LPG than for CNG, or LNG, (Moore, 93). Propane does however have its disadvantages. It does not burn as cleanly as CNG. In addition, propane vapors are heavier than air and tend to collect in low spots in explosive concentrations. Vehicle collisions that cause leaks might create dangerous situations quickly,” (Moore, 93). Finally, retrofitted propane vehicles are void of warranty by all manufacturers, (Moore, 93). Until LPG vehicles are made attractive to the consumer, they will never catch on; however, certainly a cost-effective LPG vehicle seems feasible. Alcohols: The next category of