亚洲精品一区-91视频免费在线观看-老司机精品福利视频-日本国产一区-国产黄色精品-久久久久久亚洲精品

GRE寫作范文——Coal-fired power plants

雕龍文庫 分享 時間: 收藏本文

GRE寫作范文——Coal-fired power plants

  The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap, readily available fuel with which to generate large amounts of electric power. Coal seemed to fit the bill, and it fueled the earliest power stations. . As more power plants were constructed throughout the country, the reliance on coal increased throughout the country, the reliance on coal increased. Since the First orld War, coal-fired power plants had a combined in the United States each year.

  In 1986 such plants had a combined generating capacity of 289,000 megawatts and consumed 83 percent of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of nuclear ower and in the supply of oil and natural gas, coal-fired power plants could well provide up to 70 percent of the electric power in the United States by the end of the century.

  Yet, in spite of the fact that coal has long been a source of electricity and may remain on for many years, it has actually never been the most desirable fossil fuel for power plants. Coal contains less energy per unit of weight than weight than natural gas or oil; it is difficult to transport, and it is associated with a host of environmental issues, among them acid rain. Since the late 1960s problems of emission control and waste disposal have sharply reduced the appeal of coal-fired power plants. The cost of ameliorating these environment problems along with the rising cost of building a facility as large and complex as a coal-fired power plant, have also made such plants less attractive from a purely economic perspective.

  Changes in the technological base of coal-fired power plants could restore their attractiveness, however. Whereas some of these changes are intended mainly to increase the productivity of existing plants, completely new technologies for burning coal cleanly are also being developed.

  

  The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap, readily available fuel with which to generate large amounts of electric power. Coal seemed to fit the bill, and it fueled the earliest power stations. . As more power plants were constructed throughout the country, the reliance on coal increased throughout the country, the reliance on coal increased. Since the First orld War, coal-fired power plants had a combined in the United States each year.

  In 1986 such plants had a combined generating capacity of 289,000 megawatts and consumed 83 percent of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of the nearly 900 million tons of coal mined in the country that year. Given the uncertainty in the future growth of nuclear ower and in the supply of oil and natural gas, coal-fired power plants could well provide up to 70 percent of the electric power in the United States by the end of the century.

  Yet, in spite of the fact that coal has long been a source of electricity and may remain on for many years, it has actually never been the most desirable fossil fuel for power plants. Coal contains less energy per unit of weight than weight than natural gas or oil; it is difficult to transport, and it is associated with a host of environmental issues, among them acid rain. Since the late 1960s problems of emission control and waste disposal have sharply reduced the appeal of coal-fired power plants. The cost of ameliorating these environment problems along with the rising cost of building a facility as large and complex as a coal-fired power plant, have also made such plants less attractive from a purely economic perspective.

  Changes in the technological base of coal-fired power plants could restore their attractiveness, however. Whereas some of these changes are intended mainly to increase the productivity of existing plants, completely new technologies for burning coal cleanly are also being developed.

  

主站蜘蛛池模板: 国产成人综合日韩精品无 | 亚洲人成综合网站在线 | 免费 成年人 | 国产亚洲欧美日韩在线观看一区二区 | 久久久久久日本一区99 | 亚洲欧美成人影院 | 玖玖爱zh综合伊人久久 | 一级做a爱过程免费观看 | 国产伦久视频免费观看 视频 | 欧美观看一级毛片 | 久久精品网站免费观看 | 国产农村乱子伦精品视频 | 午夜伦4480yy妇女久久久 | 亚洲美女综合网 | 一色屋色费精品视频在线观看 | 三级视频在线 | 欧美 亚洲 中文字幕 | 天天草综合| 国产在视频线精品视频二代 | 欧美精品另类hdvideo | 亚洲美女视频在线观看 | 亚洲免费高清视频 | 国产精品资源手机在线播放 | av av片在线看 | 男女在线观看视频 | 亚洲精品久久久久午夜三 | 91精品国产免费久久国语蜜臀 | 亚洲欧美综合一区二区三区四区 | 国内精品国语自产拍在线观看55 | 久久美女精品国产精品亚洲 | 国产精品久久视频 | 最近日本免费观看视频 | 成熟女人免费一级毛片 | 欧美在线综合视频 | 亚洲成人福利网站 | 久久久精品国产免费观看同学 | 久久久免费精品 | 成人国产免费 | 国产美女精品视频 | 国产成人精品午夜二三区 | 成人在线免费网站 |