42.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 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, 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.
2017届高中英语一轮复习精品学案:【外研版】必修4 Module1—6
2017高考英语一轮复习(大纲版)限时提能精练1-5
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 19-20
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 1-2
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅡ Units 13-14
2017高考英语一轮复习(大纲版)限时提能精练2-4
2017高考英语一轮复习(大纲版)限时提能精练1-1
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅡ Units 9-10
2017高考英语一轮复习(大纲版)限时提能精练1-14
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 7-8
2017高考英语一轮复习(大纲版)限时提能精练2-11
2017届高中英语一轮复习精品学案:【外研版】选修7 Module1—6
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 11-12
2017高考英语一轮复习(大纲版)限时提能精练2-2
2017高考英语一轮复习(大纲版)限时提能精练1-4
2017届高中英语一轮复习精品学案:【外研版】选修6 Module1—6
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅡ Units 19-20
2017高考英语一轮复习(大纲版)限时提能精练1-22
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 17-18
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 9-10
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 3-4
2017高考英语一轮复习(大纲版)限时提能精练1-3
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅡ Units 15-16
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 13-14
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 5-6
2017届高中英语一轮复习精品学案:【外研版】选修8 Module1—6
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅡ Units 1-2
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅡ Units 5-6
2017高考英语一轮复习(大纲版)精品课件 专题1
【人教大纲版】2017届高考英语一轮复习精品学案:SBⅠUnits 21-22
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |