The invention of the incandescent1 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 uncertainty2 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
emission3 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
purely4 economic perspective.
Changes in the
technological5 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.
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1
incandescent
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adj.遇热发光的, 白炽的,感情强烈的 |
参考例句: |
- The incandescent lamp we use in daily life was invented by Edison.我们日常生活中用的白炽灯,是爱迪生发明的。
- The incandescent quality of his words illuminated the courage of his countrymen.他炽热的语言点燃了他本国同胞的勇气。
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2
uncertainty
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n.易变,靠不住,不确知,不确定的事物 |
参考例句: |
- Her comments will add to the uncertainty of the situation.她的批评将会使局势更加不稳定。
- After six weeks of uncertainty,the strain was beginning to take its toll.6个星期的忐忑不安后,压力开始产生影响了。
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3
emission
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n.发出物,散发物;发出,散发 |
参考例句: |
- Rigorous measures will be taken to reduce the total pollutant emission.采取严格有力措施,降低污染物排放总量。
- Finally,the way to effectively control particulate emission is pointed out.最后,指出有效降低颗粒排放的方向。
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4
purely
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adv.纯粹地,完全地 |
参考例句: |
- I helped him purely and simply out of friendship.我帮他纯粹是出于友情。
- This disproves the theory that children are purely imitative.这证明认为儿童只会单纯地模仿的理论是站不住脚的。
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5
technological
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adj.技术的;工艺的 |
参考例句: |
- A successful company must keep up with the pace of technological change.一家成功的公司必须得跟上技术变革的步伐。
- Today,the pace of life is increasing with technological advancements.当今, 随着科技进步,生活节奏不断增快。
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