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Alternate Fuels Essay Research Paper Jennifer Allers (стр. 2 из 2)

Electric Power:

Electric powered vehicles also qualify as alternatively powered vehicles. Three types of vehicles are currently being developed not including solar powered vehicles. These include 100% electric vehicles, vehicles with range extending generators and regenerative braking devices, and electric, ICE hybrids, (Moore, 92). Battery powered vehicles have the advantage of zero emissions. This does not necessarily make them environmentally friendly. Power does not come from the air (unless its solar). Electric must be generated at some point. In California, where 30% of electricity is produced by coal, electric vehicles lose some of their luster. In the east, 50% of power is produced with coal. Power plants are not located in cities, they are located outside of city limits which helps the local smog situation, but not the environment, (Derr, 32). A power plant burning natural gas in the LA basin by 2001 and supplying electric power will contribute .9 lb/Yr. ozone precursors per car. Gas fired generators will produce 7 to 12 lb/yr. Coal fired plants will produce 30 to 42 lb/Yr. which is three times what new 1995 gasoline powered vehicles produce. This is not the only pollution. Batteries wear out and have to be replaced at approximately $2000. They contain heavy metals which must be recovered so as not to be released to the environment. Batteries also weigh 1000+ lb. Technology has limited their range to city driving until this point. A Massachusetts firm has used a nickel metal hydride battery to extend the range of its Sunrise concept car to 238 miles in a recent road rally in New England. The battery, developed by Ovonic Battery Corp. in Michigan, will begin sales of the battery in January of 1996. The Sunrise concept car will enter full production in 1998 with 20,000+ cars per year, (Nadis, 45). Cost is still high. Robert Eaton, chairman of Chrysler, was quoted as saying his company will have to sell electric minivans for less than $18,000 even though they cost up to $45,000 to build. He will make up for the loss by adding $2000 to every other vehicle he sells in California, (Derr, 32).

Electric vehicles also have a limited driving range, are still technically inferior, and are not “consumer familiar,” (Moore, 93). According to a new analysis by the International Energy Agency (IEA), Cars and Climate Change, it is estimated that an electric car operated on coal power could contribute as much as 200% more emissions than a petrol car over its life cycle.

Environmentally, electric cars would make sense in countries such as France, Sweden, Switzerland, Norway, New Zealand, and Iceland, which have a high percentage of nuclear or hydro electricity production. However, such cars would increase emissions in the UK, where 68% of the nationally generated electricity comes from coal, and throughout the United States, (Bond, 13). The U.S. has few hydro electric generating stations and is in the process of closing its nuclear power plants thereby rendering the electric car without advantage monetarily, technologically, realistically, and environmentally. This source is not only unwise to pursue, it is also only feasible in a limited sense. In only one sense is electric a wise avenue to pursue; when it is coupled with the hydrogen fuel cell, (Williams,25).

Hydrogen:

Hydrogen is the last alternative fuel warranting significant attention and it will quite possibly be the fuel of the future one century from now if no new methods of propulsion and / or power are discovered in the next century. Hydrogen has many advantages and disadvantages most of which seem solvable by existing technology. The most obvious advantages are that it is by far the most abundant element in the universe, it packs more energy per unit of weight than any other fuel, and it burns cleanly, (Johnstone, 90). BMW has currently been researching the hydrogen alternative for one decade, (Siuru, 65).

Hydrogen fuel cells are the most popular area of research at the moment in an attempt to deal with the dangerous hydrogen storage problem. The cells convert a fuel’s energy directly into electricity, without combustion and without moving parts. The main features of the fuel-cell system are a fuel supply, an oxidant (typically oxygen from the air), and two electrodes with an electrolyte sandwiched between them. A type of fuel cell that promises to be both compact and inexpensive enough for a practical automobile is the proton-exchange-membrane fuel cell. Aside from cost, the features of the fuel-cell car of greatest interest to the consumer are fuel economy, performance, refueling time, and range between refueling. Fuel-cell cars operated directly on hydrogen would be 3 times as energy-efficient as comparable gasoline cars. They would also be much quieter and require less maintenance than ICE’s, (Williams, 27). Current cell weight includes 97% weight for the cell, and 3% weight for the gas. A high efficiency, light weight cell is needed that will not rupture causing explosion in an automobile accident, (Knott, 28). A hydrogen fuel cell hybrid has been suggested and estimated to be 50% efficient, (Knott, 30). Ammonia can also be used as a hydrogen carrier, spawning ammonia fueled vehicles. Ammonia also has the advantage of being carbon free and has a substantial infrastructure, (Knott, 30). The U.S. Army tested but abandoned ammonia as fuel in the 1960’s.

Engineers at Johns Hopkins are again researching the concept. Automobile makers in Germany have experimented with hydrogen-burning cars for 2 decades, and it will be years before they come to market. The Persian Gulf war piqued interest in alternative fuels, and new clean-air laws make hydrogen seem more sensible than it once did. Burning it mainly creates steam, most of which condenses and trickles out

the tail pipe with only a few nitrous oxides left over. Japan’s Mazda Motor Corp. hopes to sell a few hydrogen cars in California within 10 years. The main problem, according to Wolfgang Reitzle of BMW, is how to produce and distribute hydrogen. So far, Mercedes-Benz, BMW, and Mazda prototypes are using gasoline engines that have been modified for hydrogen, although not yet optimized. The key question is how the fuel should be stored. Mercedes has opted for gaseous hydrogen that bonds in the fuel tank with powdered metals, a fuel cell; Mazda plans a tank that stores hydrogen in metal alloy balls; BMW uses cryogenic liquid hydrogen injected directly into the cylinders, (Hoffman, 24), as well as fuel cell technology. Used correctly, the companies insist, hydrogen is as safe as gasoline, (Templeman, 59). Hydrogen is being readily researched and certainly evidences itself as being a feasible alternative fuel.

Turbine:

Finally I will briefly touch on turbine cars / engines. They are of course not alternative fuels, but can run on them more efficiently than any conventional ICE. Although most of the work on alternative car engine technologies has concentrated on electric vehicles, run by either fuel cells or batteries, another option deserving of a hard look is the gas turbine engine. Compared with the ICE, gas turbine engines weigh less, are longer-lasting, and break down less frequently. The gas turbine engine excels in terms of emissions; it is the only automotive engine technology to have met the most stringent limits tentatively set by the Environmental Protection Agency. The gas turbine vehicle also has some clear benefits over batteries and fuel cells. They can burn a variety of fuels and are compact sources of power, capable of producing 3-4 kilowatts per kilogram, versus less than 1.5 kilowatts per kilogram from a fuel cell and 0.5-1.0 kilowatts per kilogram from a battery system of a size sufficient to provide an acceptable range, (Wilson, 55).

As mentioned in the beginning of this paper, there are advancements in the automotive and engine field constantly. The advancements in this field coupled with the viable alternative fuel options discussed in this paper could produce a vehicle excelling monetarily, technologically, realistically, and environmentally.

Brazil:

Brazil is becoming more and more capitalist, but the government still con- trols fuel prices. Alcohol is more expensive to produce these days than gasoline, but at the pump the prices of alcohol and gas are the same per liter. The price translates into about $2/gallon. The government is subsidizing the price of the alcohol by setting a high price for gasoline. People are buying less and less cars powered by alcohol for several reasons.

1. It is still slow to start the car when cold. As you know, you can start a

gasoline-powered car and move right away, even when it is cold.

Alcohol-powered cars have to be warmed before moving in cool weather, or

you risk having the engine die in the middle of the road.

2. Alcohol-powered cars are more expensive than their gasoline

counterparts because the metal requirements are more stringent to

minimize corrosion by the flue gases. Furthermore, they need a small, 1

liter gasoline tank just to start the engine. There is not enough energy

content in the anhydrous ethanol to start the engine. A few seconds

after start-up, the gasoline flow stops and the alcohol flow starts.

3. Even with better metals, corrosion problems are far worse than those

of gasoline engines.

4. Even with a subsidy, it is more expensive to operate alcohol-powered

cars because they make less kilometers per liter of alcohol (or should I

say miles per gallon)?

At the peak of the oil crisis, in the early 80’s, alcohol-powered sales

were about 50% of the market. Nowadays it is less than 10% of the total

car sales. It is not zero because of the subsidy (Kumpinsky).

United States:

Similarly, in the U.S. chemical companies cannot keep up with ethanol demand. The market for fuel grade ethanol has grown explosively in the past decade; however, corn prices are rising (the “biomass” source of ethanol) and the market’s long term viability is uncertain. “The renewable fuels requirement didn’t happen the way people expected,” (Hoffman, 5). Currently ethanol sales are “through the roof” and companies are selling every gallon manufactured, (Hoffman, 5).

“Indeed the alcohol program is getting smaller and smaller, but it will

not go away. In case there is another fuel crisis, the country, [Brazil], will

have the technology to satisfy its energy, if people replace their gasoline

powered engines with alcohol powered ones. Even with better alloys and

coatings, corrosion is still a problem.

I think the problem of corrosion and lower mileage per gallon is due to

the same problem in complete combustion. You ca