Sugar: Friend or Foe?
Authored by Ke-ai Xiao
Submitted to: Ms. Xuehua Wang
Southeast University
Submission date: December 10, 2017
Abstract
    Nuclear energy has become the subject of considerable debate, with its proponents claiming that it is beneficial for the environment. This essay attempts to assess the risks of using nuclear power, in comparison with other sources of energy. The main arguments for employing nuclear energy are first considered, followed by an examination of the safety issues around this source of power, including the safety and security concerns connected with nuclear waste. It appears that many of these concerns are exaggerated, and that nuclea
r energy can be seen as a safe, reliable and cost-effective alternative to using fossil fuels. Clearly more could be done to make nuclear plants safer and more efficient in future. (字数要求: 100-150 words)
    The rationale behind using nuclear energy stems from the need to find alternative energy sources to fossil fuels (i.e. oil, gas and coal), which are finite. This is a growing concern, due to the increase in the global population, which is accompanied by an increase in energy demand. Mathew (2006) indicates that the annual energy consumption rate per capita in developed countries is between 4,000 and 9,000 kg of oil, while the rate in less developed countries is around 500 kg. As a result, the demand for total primary energy, which will accompany the population growth, is projected to increase from 12.1 Mtoe (million tons of oil equivalent) to 16.1 Mtoe in 2030. If this increase occurs the total global stock of oil and gas would only be adequate for 250 years, thus requiring the urgent development of other energy sources, which would not deplete the stock of natural resources available for future generations.
    Wind energy and solar power are frequently presented as alternative energy sources to fossil fuels. Both are freely available in many parts of the world and their use involves no CO2 emissions. Sterrett (1994) claims that sufficient wind energy exists to displace approximately eight billion barrels of oil. However, wind energy is unreliable, as wind turbines do not function if the wind speed is too high or low. Similarly, solar power is only effective during the day, and is uneconomic in cool and cloudy climates. Neither of these sources currently offers an efficient and reliable alternative to energy created from fossil fuels.
    An important reason for using nuclear energy is to reduce the emissions of CO2, which are produced by burning fossil fuels. This type of fuel is the main source of the increase in atmospheric carbon dioxide. The amount of CO2 produced by each source differs due to the differences in their hydrogen content. For example, natural gas contains one carbon atom and four hydrogen atoms, which combine with oxygen to produce CO2. The proportion of CO2 is lower than with the other sources, because the emission depends on the mass of carbon inside the chemical compounds. Although natural gas is thus cleaner th
an the alternatives, burning all three fuels contributes to the greenhouse effect which is causing the earth to heat up.
    Nuclear energy, however, emits no carbon dioxide, sulphur dioxide (SO2) or nitrous oxide (NOx). It is estimated that in 2003, in the USA, nuclear energy prevented the release of 680 million tons of CO2, 3.4 millions tons of SO2 and 1.3 million tons of NOx. If released from coal burning plants, these gases would have caused the deaths of 40,000 people annually.
    Nuclear energy could potentially generate more electricity than other current sources. As Murray (2000, p.73) explains “a typical reactor, which consumes 4 kg/day of uranium U235, generates 3,000 MW of energy a day”, while other sources such as natural gas, coal or oil require many times the equivalent of that amount of uranium to generate the same energy. Therefore nuclear energy is relatively cost efficient as it uses a cheap raw material.
    In recent years the price of oil and natural gas has risen sharply, and this trend seems likely to continue in future. The cost of purchasing fuel for nuclear energy is likely to remain
low compared to other energy sources, so it seems likely that this cost advantage will become a significant factor in the comparison between nuclear and other energy sources.
References
Mathew, S. (2006) Wind Energy: Fundamentals, Resource Analysis and Economics. Berlin: Springer.

Murray, L. R. (2009) Nuclear Energy. An Introduction to the Concepts, System and Application of the Nuclear Process. Oxford: Butterworth.

Sterrett, T. (1994) Nuclear energy engagement: Improving participation in circulation. Recyclable Energy, 53(12), 40-45.
Original sentences:
Mathew, S. (2006):
    “Paraphrasing is a practical method used when wanting to rephrase the content of a sou
reactor thenrce. This technique is useful in preventing plagiarism and excessive quotations.”

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