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.
初一英语阅读理解:我是Jim
MODULE 3 My new school
英语导读1000句(九)
初一英语阅读理解汇总
初一英语阅读理解:周末
初一英语阅读理解:Mr. Martin
初一英语自我介绍精选范文
What does he look like
初一英语阅读理解:招聘老师
英语导读1000句(二)
初一英语阅读理解:新公园
英语导读1000句(八)
初一英语阅读理解:西方的购物方式
初中生必备短语:P(2)
初中生必备短语:P(1)
初一英语自我介绍范文
初中英语知识点归纳:主动语态与被动语态
英语导读1000句(十五)
Unit 9 My favorite subject is science教案及反思
MODULE 4 My family
潮流英语词汇集锦(一)
英语导读1000句(十二)
初中生必备短语:S(2)
MODULE 7 My school day
英语导读1000句(十)
初中生必备短语:R(2)
英语导读1000句(四)
潮流英语词汇集锦(四)
七年级英语Unit 3 Family and friends教案
初一英语阅读理解:美食
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