Is that good to use ethanol as an alternative fuel.doc

1、Issue investigationIs that good to use ethanol as an alternative fuel?G5MaxWord count: 1035Ethanol fuel also known as alcoholic gasoline is a new kind of clean and green car fuel which is a mixture of certain percentage of denatured ethanol fuel and gasoline through a specific process according to n

2、ational standard GB18351-2004 quality requirements by the ethanol gasoline deployment centre. Nowadays, the boom of ethanol has being keeping rising. According to Wikipedia, World ethanol production for transport fuel tripled between 2000 and 2007 from 17 billion to more than 52 billion liters. From

3、 2007 to 2008, the share of ethanol in global gasoline type fuel use increased from 3.7% to 5.4%. Due to its special properties, it is very favored around the world. Firstly, ethanol fuel has a good effect of combustion-supporting. If we add ten percent of ethanol into gasoline, its oxygen content c

4、an reach 3.5 percent. So the combustion of gasoline will be completed easily because less oxygen is needed. Equation of combustion for gasoline and ethanol: )(2)(2)(2)(18 18165C2 lggl OHCOH)()()(5 33llSecondly, because its solubility is good, this can clean the oil circuit of the car. The ethanol in

5、 ethanol gasoline is an excellent organic solvent. So it can effectively eliminate the impurities of precipitation and condensation in the fuel tanks and oil circuit system of the automobile. It plays an important role in cleaning the oil circuit.Thirdly, because ethanol makes the gasoline combust c

6、ompletely, it can reduce the carbon deposition effectively. The carbon deposition at spark plug, valve, piston crown, exhaust pipe, muffler and other parts of the engine would be reduced effectively, so that the life of the engine and other major components would be extended.Last but not least, it i

7、s a kind of clean fuel. When it burn, it would not release any toxic and harmful gases. (Under the condition of complete combustion) The equation of combustion is: )(2)(22)(52 33lgl OHCOHCSo it wont cause any air pollution.However, does ethanol fuel really bring people benefits? Actually the way we

8、used nowadays to produce the ethanol does not have many advantages. The commercial ethanol we use nowadays is all made from corn. This kind of production is energy-intensive modes of production. Some studies suggest that the energy consumption of refining a gallon of ethanol is even higher than the

9、energy it can supply when it burns. Even some studies suggest that the net income created by the corn-based ethanol is next to nothing. Another oppose study showed that compared to the crude oil - gasoline cycle, the effect of corn - ethanol cycle that we used to reduce greenhouse gases is almost ne

10、gligible. So before ethanol manufacturers improve the way of using cellulosic to produce ethanol, corn-based ethanol has nothing to do with economic or environmental significance.Many people believe that the ethanol produced by corn is a kind of renewable energy. Because the energy generated by usin

11、g a kind of resource, sunlight, cannot be depleted. According to Wikipedia, creation of ethanol starts with photosynthesis causing a feedstock, such as sugar cane or a grain such as maize (corn), to grow. This feedstock is processed into ethanol. However, according to the latest survey, to produce o

12、ne gallon of corn-based ethanol cannot make ends meet. The consumption of other energy like natural gas or diesel is almost close to or even higher than the energy it produced. Moreover, the carbon dioxide released in each process of production is also contrary to the original intention of clean ene

13、rgy. Most of the ethanol produced in the world has been used as a class of gasoline additive. It can be mixed with gasoline in the ratio of 1:9 which is the highest proportion that ordinary engines are able to use without been damaged. For ordinary engine, ethanol is like the alcohol contained in th

14、e distilled liquor. It will corrode the seals in the engine and fuel system. So 10 percent is the highest rate which can be accepted.And many other problems have appeared too. The first problem is a standard barrel (42 gallons) of ethanol is only equal to 28 gallons of gasoline. This is because a st

15、andard barrel of regular unleaded gasoline contains about 125,545,000 joules of energy. In contrast, a standard barrel of ethanol contains only 84,400,000 joules of energy. Therefore, when you fill the oil tank with ethanol gasoline, you actually didnt fill the same amount of gasoline. Even if the p

16、rice of a gallon of ethanol is cheaper, if you want to drive the same mile of a gallon of gasoline that can drives you, you have to buy more ethanol. The second problem is that we are lacking of some necessary resources we need to produce the ethanol. Corn is indeed a rich resource. However, produci

17、ng ethanol needs a large amount of natural gas. Yeast can turn the sugar into alcohol and carbon dioxide. The equation is:)(2)(52)(6126C glyeasts COHCOH Then evaporate the alcohol after distillation. The last step is to collect and condense the alcohol. Each step in production processes needs to use

18、 natural gas to heat. At present, the production of a gallon of ethanol (contains 80,000 British thermal units of energy) will need about 3.6 million British thermal units of natural gas. The efficiency is too low. Some ethanol producers are trying to use coal to replace natural gas. But this is als

19、o contrary to the definition of clean energy and renewable energy. Burning coal will release large amounts of carbon dioxide. Thus, the vehicles which use ethanol fuel will do much more serious effect on climate changes than the vehicles use regular gasoline. In theory, they can use electricity. But

20、 electricity is also produced by burning coal. The production of ethanol also needs some other form of energy. Ethanol cant use pipeline to transmit like gasoline or diesel. Because water is easy to get into this kind of pipeline and ethanol is a polar molecule which can form hydrogen bond with wate

21、r while gasoline or diesel is not soluble in water. Once it mixed with water, it will undermine the calorific value of ethanol fuel. To transmit ethanol to market, we need to use the truck. Sometimes it is a long-distance transport which must consume a lot of diesel. In addition, using reaper to har

22、vest corn also consume diesel and also the production process of fertilizer that is used to plant corn also can not be separated from natural gas.After Investigated a variety of research reports, Assistant Professor Alexander E Farrell of University of California and his co-operation writer conclude

23、d that the ethanol produced by natural gas is a little bit better than gasoline in the aspect of air pollutants. However, the ethanol produced by coal is worse. (http:/ Although there are disagreements with this argument, it is still evident. So using the limitation of carbon dioxide emissions as th

24、e reason to advocate ethanol fuel is unreliable. The benefits brought by ethanol in the aspect of reduction of greenhouse gases are negligible. Wed better find other ways to replace our traditional fuel.Bibliography1. en.wikipedia.org/wiki/Ethanol_fuel2. Muchu Qin, May 27, 2012 http:/ Nelson, July 22, 2012 http:/www.thealternativeenergy.info/4. Paul Frisman, September 5, 2006http:/www.cga.ct.gov/2006/rpt/2006-r-0524.htm