考研英语 学英语,练听力,上听力课堂! 注册 登录
> 考研英语 > 考研英语阅读 >  内容

《考研英语阅读理解100篇 基础版》第4章 科学研究类 Unit 47

所属教程:考研英语阅读

浏览:

2019年01月13日

手机版
扫描二维码方便学习和分享

Usually alternating current(AC)transmission suffers lower losses than direct current(DC),and thus,AC became the industry standard.Some people,however,question that standard because over long distances high-voltage DC lines suffer lower losses than AC.Not only does that make them better in their own right,but employing them would allow electricity grids to be restructured in ways that would make wind power more attractive. That would reduce the need for new conventional(and polluting)power stations. 
Wind power has some problems.You don’t always get it where you want it and you don’t always get it when you want it.The question of where the wind is blowing would no longer matter because it is almost always blowing somewhere.If it were windy in Spain but not in Ireland,current would flow in one direction.Dealing with when the wind blows is a subtler issue.For instance,an important part of Dr Schmid's continental grid is the branch to Norway.It is not that Norway is a huge consumer.Rather,the country is well supplied with hydroelectric plants.These are one of the few ways that energy from transient sources like the wind can be stored in grid-filling quantities.The power is used to pump water up into the reservoirs that feed the hydroelectric turbines.That way it is on tap when needed.The capacity of Norway's reservoirs is so large,according to Dr Schmid,that should the wind drop all over Europe—which does happen on rare occasions—the hydro plants could spring into action and fill in the gap for up to four weeks. 
Put like this,a Europe-wide grid seems an obvious idea.That it has not yet been built is because AC power lines would lose too much power over such large distances.Hence the renewed interest in DC.Dr Schmid calculates that a DC grid of the sort he envisages would allow wind to supply at least 30% of the power needed in Europe.Moreover,it could do so reliably—and that means wind power could be used for what is known in the jargon as base-load power supply. 
Though wind power has its opponents,too,its environmental virtues might be enough to swing things in its favour if it were also reliable.Indeed,a group of Norwegian companies have already started building high-voltage DC lines between Scandinavia,the Netherlands and Germany,though these are intended as much to sell the country's power as to accumulate other people’s.And Airtricity—an Irish wind-power company—plans even more of them.It proposes what it calls a Supergrid.This would link offshore wind farms in the Atlantic Ocean and the Irish,North and Baltic seas with customers throughout northern Europe. 
注(1):本文选自Economist; 
注(2):本文习题命题模仿对象为2004年真题Text 3。 
1.By saying“make them better in their own right” (Lines 3~4,Paragraph 1),the author means to _______. 
A) realize the right of DC 
B) make DC suffer lower losses 
C) make DC more useful than AC 
D) make better use of DC to transfer power 
2.By saying“Dealing with when the wind blows is a subtler issue” (Line 4,Paragraph 2),the author actually implies that _______. 
A) it is more difficult to predict the time when the wind blows 
B) it is more intricate to deal with the wind since it is always transient 
C) it is more complex to control the wind in the temporal sense 
D) it is more complicated to utilize the wind power 
3.How will consumers think of a DC electricity grid? 
A) Not feasible yet. 
B) Quite economical. 
C) Somewhat troublesome. 
D) Too bold. 
4.Why is Dr Schmid's continental grid located in Norway? 
A) To make use of the country's capacity of reservoirs so as to store temporary power. 
B) To make use of the country's rich wind power so as to meet consumers’ demand. 
C) To make better use of the country's rich hydroelectric power to supply other European countries. 
D) It is simply Dr Schmid's personal preference of that country. 
5.Which of the following is TRUE according to the passage? 
A) Wind power has won universal support. 
B) Companies hesitate to invest in wind power. 
C) The prospect of wind power so far seems very positive. 
D) Wind farms on oceans can supply power demand of the whole Europe in the future. 

一般来说,交流电传输比直流电传输损失的电量要少,因此,交流电成为了工业上的标准。但是一些人却在质疑这个标准,因为从远距离传输来看,高压直流电缆损失的电量比交流电缆少。这不仅能有利于电流的传送,而且通过使用高压直流电缆,人们可以对电网进行改造,从而更加有利于风能发电。如此一来,对于新建更多传统(也是污染的)发电站的需求就会减少。 
风能发电存在一些问题。风能不是随处都在,也非随时可得。但是现在哪里有风的问题已经得到解决,因为总有地方在刮风。如果现在西班牙多风而爱尔兰却无风,那么电流就会朝一个方向传送。但是,风在什么时候吹则是一个更微妙的问题。比如说,史密德博士设计的大陆电网的重要一部分就位于挪威。但这并不是因为挪威消费很多的电能,而是这个国家到处都是水电站。利用水电站是可以把如风能等稍纵即逝的能源大量储存起来的方式之一。通过使用这些风能,人们可以把水往上抽到水库中推动水电涡轮。水电站以这个方式就可以随时把水抽上来。史密德博士认为挪威水库容量如此之大,以至于如果欧洲所有的地方都不刮风了——这种现象确实偶尔会发生——挪威的水电站仍然可以继续运转并供应整个欧洲的用电量达四周之久。 
如果情况真是这样的话,那么建设一个跨欧洲的电网是势在必行的了。此前没有进行该项目建设是因为交流电缆在进行如此远距离传输的时候会损失大量的电能。而现在人们开始思考用直流电缆来实现这一设想。史密德博士估计,他设想的这种直流电缆能够使风能满足全欧洲至少30%的用电需求。此外,这样做也非常可靠——从术语上说,这意味着风能可以被称为是基本负荷型电能供应。 
尽管对于风力发电也有反对者,但是如果风能可靠的话,那么其清洁环保的特点足以赢得广泛的支持。实际上,一些挪威的公司已经开始在斯堪的纳维亚、荷兰和德国之间建设高压直流电缆,尽管他们的目的在于销售本国的能源并积累他人的能源。此外,一家爱尔兰风能公司Airtricity则计划比挪威的公司们做的更多。该公司提出了一个所谓的超级电网的概念,该电网能够将大西洋、爱尔兰海、北海和波罗的海上的风能电厂与整个北欧的消费者们连接起来。 
用户搜索

疯狂英语 英语语法 新概念英语 走遍美国 四级听力 英语音标 英语入门 发音 美语 四级 新东方 七年级 赖世雄 zero是什么意思长沙市蓝色港湾英语学习交流群

  • 频道推荐
  • |
  • 全站推荐
  • 推荐下载
  • 网站推荐