背景: #EDF0F5 #FAFBE6 #FFF2E2 #FDE6E0 #F3FFE1 #DAFAF3 #EAEAEF 默认  
英语学习网 www.enfang.com  添加到百度搜藏 添加到百度搜藏   

Coal-fired power plants

[日期:2006-12-02] 来源:  作者: [字体: ]
收藏到QQ书签

3854本英语图书  英语交友 - 学习英语的朋友都在这里    ★5天5夜突破英语听说,100%保证!点击进入

   免费英语口语在线测试   武林三国网页游戏   广告位招商:英语培训机构的选择

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. (which were set up at the end of the nineteenth century by Edison himself). 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 World 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 power 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(coal represents about 80 percent of United States fossil-fuel reserves), 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 1960's 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.

阅读:


推荐 】 【 打印
上一篇:《考研英语考前30天狂背作文》二
下一篇:Museums
英语学习相关资料       考研  作文 
本文评论       全部评论
发表评论


点评: 字数
姓名:

  • 英语学习MSN群:group2058@bbqun.com