最近中文字幕完整版高清,宅男宅女精品国产av天堂,亚洲欧美日韩综合一区二区,最新色国产精品精品视频,中文字幕日韩欧美就去鲁

首頁(yè) > 優(yōu)秀作文 > 英語(yǔ)作文 > 考研英語(yǔ)作文 > Coal-fired power plants

Coal-fired power plants

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. (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 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(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 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.

Coal-fired power plants 相關(guān)內(nèi)容:
  • Folk Cultures

    A folk culture is a small isolated, cohesive, conservative, nearly self-sufficient group that is homogeneous in custom and race with a strong family or clan structure and highly developed rituals....

  • Bacteria

    Bacteria are extremely small living things. While we measure our own sizes in inches or centimeters, bacterial size is measured in microns. One micron is a thousandth of a millimeter: a pinhead is about a millimeter...

  • Sleep

    Sleet is part of a person's daily activity cycle. There are several different stages of sleep, and they too occur in cycles. If you are an average sleeper, your sleep cycle is as follows....

  • Cells and Temperature

    Cells cannot remain alive outside certain limits of temperature and much narrower limits mark the boundaries of effective functioning. Enzyme systems of mammals and birds are most efficient only within a narrow range...

  • Two Attitudes Toward Part-time Jobs

    Some peolpe think there are more advantages for colleges students to take part-time jobs than disadvantages, others don't think so. What's your view on this? And tell why....

  • 2003年考研胡敏預(yù)測(cè)英語(yǔ)范文14篇

    如何是作文的時(shí)態(tài)簡(jiǎn)單化,以最大程度地避免錯(cuò)誤?參加國(guó)際上的任何一場(chǎng)考試,只要是寫(xiě)英語(yǔ)作文,主體上應(yīng)該是一般現(xiàn)在時(shí)態(tài);只有當(dāng)你提到具體的、過(guò)去的、某一事件段發(fā)生的具體的某一件事情作為例證時(shí),可以一般過(guò)去時(shí)。...

  • 考研英語(yǔ)作文經(jīng)典結(jié)尾

    考研英語(yǔ)作文經(jīng)典結(jié)尾說(shuō)完了,畢竟要?dú)w納一番,相信各位都有這樣的經(jīng)歷,領(lǐng)導(dǎo)長(zhǎng)篇大論,到最后終于冒出個(gè)總而言之之類的話,我們馬上停止開(kāi)小差,等待領(lǐng)導(dǎo)說(shuō)結(jié)束語(yǔ)。...

  • 考研英語(yǔ)作文經(jīng)典開(kāi)頭實(shí)例

    考研英語(yǔ)作文經(jīng)典開(kāi)頭實(shí)例名人名言 開(kāi)頭有人問(wèn)了,我沒(méi)有記住名言,怎么辦?尤其是英語(yǔ)名言?,很好辦:編!原理:我們看到的東西很多都是創(chuàng)造出來(lái)的,包括我們欣賞的文章也是,所以盡管編,但是一定要聽(tīng)起來(lái)很有道理呦!...

  • 真正的富有(Real rich)

    擁有金錢(qián)和權(quán)利是很多人追逐的,也是他們認(rèn)為富有的標(biāo)志,但是擁有了這些就是真正地富有了么?affluence is the thing most people are longing for all their lives. to pursue wealth is their goal of life....

  • 考研英語(yǔ)作文