2. 考研
  3. The Features of Solar and Wind Energy Solar and wind energy seem to have captured the public’s support as potentially being

The Features of Solar and Wind Energy Solar and wind energy seem to have captured the public’s support as potentially being

admin2013-07-08  54
问题                  The Features of Solar and Wind Energy
    Solar and wind energy seem to have captured the public’s support as potentially being the primary or total answer to our electric power needs despite the fact that solar cells and wind energy systems don’t always provide electric power.
    Solar cells and wind turbines are attractive because they are "renewables" and because they emit no C02, during operation. But because solar and wind electricity are available only part of the time that consumers demand power, they cannot provide energy " on demand", something that the public requires. We expect the lights to go on when we turn on a switch, and we do not expect our computers to shut down as nature dictates.
    Large-scale electric energy Storage with hydroelectric dams is a good way to solve the problem, but when we use hydroelectric dams for electric energy storage, we reduce their electric power output, which would otherwise have been used by consumers. In other words, we suffer a loss to gain power on demand from wind and solar.
    At locations without such hydroelectric dams, which are most places, solar and wind electricity systems must be backed up 100 percent by other forms of generation to ensure against blackouts. In today’s world, that backup power can only come from fossil fuels. Then the public will pay a large amount of money for solar and wind—paying once for the solar and wind system and again for the fossil fuel system.
    Finally, because solar and wind have the capacity to deliver only 30 to 40 percent of their full power ratings in even the best locations, they provide a C02 reduction of less than 30 to 40 percent, considering the fossil fuels needed for the backup. That’s far less than the 100 percent that many people believe, and it all comes with a high cost.
    The United States will need an array of electric power production options to meet its needs in the years ahead. Solar and wind will have their places, as will other renewables. Realistically, however, solar and wind will probably only provide a modest percentage of future US power. Some serious realism in energy planning is needed, especially from analysts who are not backing one horse or another.
Which of the following statements is true according to Para. 5?
选项 A、Solar and wind energy are very efficient and effective.
B、Solar and wind energy can reduce half of the greenhouse gas.
C、Many people believe solar and wind energy are completely clean.
D、Many people know that they will spend more on the new project.
答案C
解析 事实细节题。由题干定位到第五段可知，本段主要讲述太阳能和风力发电的最后一个缺点，那就是效率不高，花费巨大且不如想象的环保。故[C]“许多人认为太阳能和风能是绝对无污染的”符合文意，故为答案。[A]“太阳能和风能效率高，效果好”，与本段意思相悖，故排除；[B]“二者可以减少50％的温室气体排放”，根据本段第一句可知，只能降低30％至40％的二氧化碳，故排除;[D]“许多人都知道他们要安装新系统需要花更多的钱”，而实际上，人们并没有意识到这一点，与文章意思不符，故排除。
转载请注明原文地址:https://www.kaotiyun.com/show/KzO4777K
0

考研英语一

相关试题推荐
随机试题
最新回复(0)