Car manufacturers and governments have been eagerly seeking a replacement for the automobile's main source of power, the internal-combustion engine. By far the most promising alternative source of energy for cars is the hydrogen-based fuel-cell engine, which uses hydrogen to create electricity that, in turn, powers the car. Fuel-cell engines have several advantages over internal-combustion engines and will probably soon replace them.
One of the main problems with the internal-combustion engine is that it relies on petroleum, either in the form of gasoline or diesel fuel Petroleum is a finite resource;. Someday, we will run out of oil The hydrogen needed for fuel-cell. engines can not easily be depleted. Hydrogen can be derived from various plentiful sources, including natural gas and even water. The fact that fuel-cell engines utilize easily available, renewable resources makes them particularly attractive.
Second, hydrogen-based fuel cells are attractive because they will solve many of the world's pollution problems. An unavoidable by-product of burning oil is carbon dioxide, and carbon dioxide harms the environment. On the other hand, the only byproduct of fuel- cell engines is water.
Third, fuel-cell engines will soon be economically competitive because people will spend less money to operate a fuel-cell engine than they will to operate an internal-combustion engine This is true for one simple reason:. A fuel-cell automobile is nearly twice as efficient in using its fuel as an automobile powered by an internal-combustion engine is. In other words, the fuel-cell powered car requires only half the fuel energy that the internal-combustion powered car does to go the same distance.
The reading states that the fuel-cell engine advantages and provides three reasons of support. However, the professor explains that the fuel-cell engines are not an alternative to replace the current engines and refutes each of the author's claims.
First, the article claims that because this new technology does not rely on petroleum, it cannot easily be depleted. Moreover, fuel cell engines can be obtained from plentiful sources, such as water and natural gas. The professor refutes this point by saying that this new engine cannot be used in the form the reading explains. Furthermore, fuel-cell engine is needed in a pure liquid stage, which has to be maintained in cold temperatures in order to store and produce correctly. Thus, cell engines are not practical and easy to use as the reading stated.
Second, the reading posits that this new source of energy will completely solve the world pollution. Since carbon dioxide is released when burning oil, it endangers the environment, but water is obtained after producing the hydrogen cell engines, which does not harm the planet. However, the professor says that this technology won't solve pollution problems. He states that hydrogen has to be purified by factories to be used. Therefore, manufacture companies will generate pollution while burning coal and oil. Perhaps, the contamination will not come from cars, but from factories.
Third, the reading says that the new way of creating energy will be eventually cost effective, yet it will compete with traditional engine prices. The professor opposes to this point by explaining that it will cost a lot of money to produce fuel-cell engines since they require a platinum material expensive to find or produce artificially. Therefore, it cannot compete with the cost of engines of traditional automobiles
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The reading states that the fuel-cell engine advantages and provides three reasons of support.
The reading states the fuel-cell engine advantages and provides three reasons of support.
Attribute Value Ideal
Score: 26 in 30
Category: Very Good Excellent
No. of Grammatical Errors: 1 2
No. of Spelling Errors: 0 2
No. of Sentences: 16 12
No. of Words: 291 250
No. of Characters: 1492 1200
No. of Different Words: 148 150
Fourth Root of Number of Words: 4.13 4.2
Average Word Length: 5.127 4.6
Word Length SD: 2.617 2.4
No. of Words greater than 5 chars: 117 80
No. of Words greater than 6 chars: 93 60
No. of Words greater than 7 chars: 58 40
No. of Words greater than 8 chars: 41 20
Use of Passive Voice (%): 0 0
Avg. Sentence Length: 18.188 21.0
Sentence Length SD: 6.405 7.5
Use of Discourse Markers (%): 0.75 0.12
Sentence-Text Coherence: 0.333 0.35
Sentence-Para Coherence: 0.525 0.50
Sentence-Sentence Coherence: 0.047 0.07
Number of Paragraphs: 4 4