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.
《惊声尖叫4》女主角回归 新三部曲正式启动
美剧资讯:邪恶力量、24、绯闻女孩、绝望主妇、加州靡情
影视资讯:《绯闻女孩》第三季首款预告
《丑女贝蒂 Ugly Betty》第四季华丽
《玩具总动员3》的超绚超清晰海报抢鲜看
2009-2010年美剧节目播出计划
2009年奥斯卡外语片报名官方名单公布
《暮光之城:新月》剧照曝光 诡异惹人眼(组图)
2009年秋季美剧播出时间表
影视资讯:绝望主妇》《超能英雄》《真爱如血》等
希斯·莱杰遗作《帕纳萨斯博士的奇幻剧院》之华丽海报
“纳尼亚”编剧执笔《飞行人》
麦莉·塞拉斯将客串《欲望城市2》演自己
“火车头托马斯”和他的朋友将再次登上大银幕
不容错过的精彩美剧《美女上错身》
麻省理工要求本科生三年看完的电影
2亿年后动物长啥样?华纳将把《未来狂想曲》拍成电影
为说服电影公司拍摄《波斯王子》而制作的宣传片曝光
《绯闻女孩》第三季首播 恰克变情圣观众受不了
2009年MTV音乐录影带颁奖礼完整版
2009年8月北美电影票房排行榜
美剧一周收视排行榜(08.10-08.16)
真田广之成为《迷失》第六季重要角色
好莱坞十大最性感的单身女星
欧美电影中最美的5条裙子
第13届好莱坞电影节好莱坞电影奖获奖名单
绯闻少女第三季剧装大盘点
影视资讯:暮光之城,绯闻女孩成美国青少年选择奖大赢家
2009年好莱坞九大最有特色明星
《僵尸领地》第二支预告片
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |