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.
以a-开头的形容词用法新探•aflutter
以a-开头的形容词用法新探·amiss
以a-开头的形容词用法新探 • agog
as…as结构的几点用法说明
以a-开头的形容词用法新探‧agape
多个形容词做定语时的排列顺序
以a-开头的形容词用法新探·awake
以a-开头的形容词用法新探·ablaze
以a-开头的形容词用法新探 • aghast
形容词absent后接介词说明
heavy traffic还是crowded traffic
你知道“the+形容词”的用法吗
sure与certain的用法区别
误用形容词或副词的常用表达
以a-开头的形容词用法新探·alone
形容词able的用法说明
以a-开头的形容词用法新探·afloat
以a-开头的形容词用法新探·asleep
表示类别和整体的形容词
形容词和副词的基本用法
以a-开头的形容词用法新探•ajar
以a-开头的形容词用法新探·astir
as good as的用法
形容词与介词的常用搭配归纳
以a-开头的形容词用法新探•alight
形容词作后置定语的规律
以a-开头的形容词用法新探 • aground
形容词和副词的语法特点
定语形容词和表语形容词
以a-开头的形容词用法新探·averse
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