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　　Coal-fired power plants 燃煤电厂

　　The invention of the incandescent light bulb by Thomas A. Edison in 1879created a demand for a cheap, readily available fuel with which to generatelarge amounts of electric power. Coal seemed to fit the bill, and it fueled theearliest power stations. (which were set up at the end of the nineteenth centuryby Edison himself). As more power plants were constructed throughout thecountry, the reliance on coal increased throughout the country, the reliance oncoal increased. Since the First

　　World War, coal-fired power plants had a combined in the United States eachyear. In 1986 such plants had a combined generating capacity of 289,000megawatts and consumed 83 percent of the nearly 900 million tons of coal minedin the country that year. Given the uncertainty in the future growth of thenearly 900 million tons of coal mined in the country that year. Given theuncertainty in the future growth of nuclear

　　power and in the supply of oil and natural gas, coal-fired power plantscould well provide up to 70 percent of the electric power in the United Statesby the end of the century.

　　Yet, in spite of the fact that coal has long been a source of electricityand may remain on for many years(coal represents about 80 percent of UnitedStates fossil-fuel reserves), it has actually never been the most desirablefossil fuel for power plants. Coal contains less energy per unit of weight thanweight than natural gas or oil; it is difficult to transport, and it isassociated with a host of environmental issues, among them acid rain. Since thelate 1960’s problems of emission control and waste disposal have sharply reducedthe appeal of coal-fired power plants. The cost of ameliorating theseenvironment problems along with the rising cost of building a facility as largeand complex as a coal-fired power plant, have also made such plants lessattractive from a purely economic perspective.