Coal-fired power plants
[size=3][color=#29384e][font=Times New Roman]The invention of the incandescent light bulb by Thomas A. Edison in 1879 created a demand for a cheap[/font][font=宋体]，[/font][font=Times New Roman] readily available fuel with which to generate large amounts of electric power. Coal seemed to fit the bill[/font][font=宋体]，[/font][font=Times New Roman] and it fueled the earliest power stations. [/font][font=宋体]（[/font][font=Times New Roman]which were set up at the end of the nineteenth century by Edison himself[/font][font=宋体]）。[/font][font=Times New Roman] As more power plants were constructed throughout the country[/font][font=宋体]，[/font][font=Times New Roman] the reliance on coal increased throughout the country[/font][font=宋体]，[/font][font=Times New Roman] the reliance on coal increased. Since the First World War[/font][font=宋体]，[/font][font=Times New Roman] coal-fired power plants had a combined in the United States each year. In 1986 such plants had a combined generating capacity of 289[/font][font=宋体]，[/font][font=Times New Roman]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[/font][font=宋体]，[/font][font=Times New Roman] 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.[/font][/color][/size][size=3][color=#29384e][font=Times New Roman] [/font][/color][/size]
[size=3][color=#29384e][font=宋体] [/font][font=Times New Roman]Yet[/font][font=宋体]，[/font][font=Times New Roman] in spite of the fact that coal has long been a source of electricity and may remain on for many years[/font][font=宋体]（[/font][font=Times New Roman]coal represents about 80 percent of United States fossil-fuel reserves[/font][font=宋体]），[/font][font=Times New Roman] 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[/font][font=宋体]；[/font][font=Times New Roman] it is difficult to transport[/font][font=宋体]，[/font][font=Times New Roman] and it is associated with a host of environmental issues[/font][font=宋体]，[/font][font=Times New Roman] among them acid rain. Since the late 1960[/font][font=宋体]‘[/font][font=Times New Roman]s 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[/font][font=宋体]，[/font][font=Times New Roman] have also made such plants less attractive from a purely economic perspective.[/font][/color][/size]
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[color=#29384e][font=宋体][size=10.5pt] [/size][/font][size=10.5pt]Changes in the technological base of coal-fired power plants could restore their attractiveness[/size][font=宋体][size=10.5pt]，[/size][/font][size=10.5pt] however. Whereas some of these changes are intended mainly to increase the productivity of existing plants[/size][font=宋体][size=10.5pt]，[/size][/font][size=10.5pt] completely new technologies for burning coal cleanly are also being developed.[/size][/color]
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