英语六级快速阅读练习：可再生能源

　　Therefore,alternative sources of energy have become very important and relevant to today's world.These sources,such as the sun and wind,can never be exhausted and therefore arc called renewable.They cause less emission and are available locally.Their use can. to a large extent,reduce chemical,radioactive, and thermal pollution. They stand out as a viable source of clean and limitless energy.These are also known as non-conventional sources of energy.Most of the renewable sources of energy are fairfy non-polluting and considered clean though biomass,a renewable source,is a major polluter indoors.

　　Solar Energy

　　Solar energy is the most readily available source of energy.It does not belong to anybody and is,therefore,free.It is also the most important of the non-conventional sources of energy because it is non-polluting and,therefore.helps in lessening the greenhouse effect.

　　Solar energy has been used since prehistoric times.but in a most primitive manner.Before 1970,some research and development was carried out in a few countries to exploit solar energy more efficiently,but most of this work remained mainly academic.After the dramatic rise in oil prices in the 1970s,several countries began to formulate extensive research and development programmes to exploit solar energy.

　　When we hang out our clothes to dry in the sun,we use the energy of the sun.In the same way, solar panels absorb the energy of the sun to provide heat for cooking and for heating water.Such systems are available in the market and are being used in homes and factories.

　　Solar energy can also be ursed to meet our electricity requirements.Through Solar Photovoltaic(SPV)cells,solar radiation gets converted into DC electricity directly.This electricity can either be used as it is or can be stored in the battery.This stored electrical energy then can be used ac night.

　　Hydro Power

　　Hydro power is one of the best,cheapest,and cleanest source of energy,although,with big dams,there are many environmental and social problems.Small dams are,however,free from these problems.This is in fact one of the earliest known renewable energy sources.in the country(since the beginning of the 20th century).

　　In fact,for the last few hundred years,people living in the hills of the Himalayas have been using water mills.or chakki,to grind wheat.Besides being free from the problem of pollution.small hydropower plants are also free from issues and controversies that are associated with the bigger projects.namely affecting the lives of thousands of people living along the banks of the rivers.destruction of large areas under forest.and seismological threats.

　　New environmental laws affected by the danger of global warming have made energy from small hydropower plants more relevant.These small hydropower piants can serve the energy needs of remote rural areas independently.The real challenge in a remote area lies in successful marketing of the energy and recovering the dues.Local industries should be encouraged to use this electricity for sustainable development.

　　It is a technology with enormous potential.which could exploit the water resources to supply energy to remote rural areas with little access to conventional energy sources.It also eliminates most of the negative environmental effects associated with large hydro projects.

　　Energy From the Sea-Ocean Thermal,Tidal and Wave Energy

　　On an averaige,the 60 million square kilometre of the tropical seas absorb solar radiation equivalent to the heat content of 245 billion barrels of oil.Scientists feel that if this energy can be tapped a large source of energy will be available to the tropical countries and to other countries as well.The process of harnessing this energy is called OTEC(ocean thermal energy conversion).It uses the temperature differences between the surface of the ocean and the depths of about lOOOm to operate a heat engine.which produces electric power.

　　Energy is also obtained from wavcs and tides.In some countries such as Japan small scale power generators run by energy from waves of the ocean,have been used as power sources for channcl marking buoys.

　　Biomass

　　Biomass is a renewable energy resource derived from the carbonaceous waste of various human and natural activities.It is derived from numerous sources,including the by-products from the timber industry.agricultural crops,raw material from the forest,major parts of household waste and wood.

　　Biomass does not add carbon dioxide to the atmosphere as it absorbs the same amount of carbon in growing as it releases when consumed as a fuel. Its advantage is that it can be used to generate electricity with the same equipment of power plants that are now burning fossil fuels.Biomass is an important source of energy and the most important fuel worldwide after coal,oil and natural gas.

　　Traditional use of biomass is more than its use in modern application.In the developed world biomass is again becoming important for applications such as combined heat and power generation.In addition,biomass energy is gaining significance as a source of clean heat for domestic heating and community heating applications.In fact in countries like Finland.USA and Sweden the per capita biomass energy used is higher than it is in India.China or in Asia.

　　Geothermal Energy

　　We live between two great sources of energy,the hot rocks beneath the surface of the earth and the sun in the sky.Our ancestors knew che value of geothermal energy;they bathed and cooked in hot springs.Today we have recognized that this resource has potential for much broader application.

　　The core of the earth is very hot and it is possible to make use of this geothermal energy(in Greek it means heat from the earth).These are areas where there are volcanoes.hot springs,and geysers,and methane under the water in the oceans and seas. n some countries,such as in the USA water is pumped from underground hot water deposits and used to heat people's houses.

　　The utilization of geothermal energy for the production of electricity dates back to the early part of the twentieth century.For 50 years the generation of electricity from geothermal energy was confined to Italy and interest in this technology was slow co spread elsewhere.In 1943 the use of geothermal hot water was pioneered in lceland.

　　Co-generation

　　Co-generation is the concept or producing two forms of energy from one fuel.One of the forms of energy must always be heat and the other may be electricity or mechanical energy.In a conventional power plant,fuel is burnt in a boiler to generate high-pressure steam.This steam is used to drive a turbine.which in turn drives an alternator through a steam turbine to produce electric power.The exhaust steam is generally condensed to water which goes back to the boiler.

　　As the low-pressure steam has a large quantum of heat which is lost in the process of condensing,the efficiency of conventional power plants is only around 35%.In a cogeneration plant,very high efficiency levels,in the range of 75%-90%,can be reached.This is so,because the low-pressure exhaust steam coming out of the turbine is not condensed,but used for heating purposes in factories or houses.

　　Since co-generation can meet both power and heat needs, it has otber advantages as well in the form of significant cost savings for the plant and reduction in emissions of pollutants due to reduced fuel consumption.

　　测试题

　　1.High concentrations of harmful gases are resulted from______________.

　　A) ozone depletion B) global warming

　　C) the consumption of fossil fuels D) serious water and air pollution

　　2.The sun and wind are called renewable energy because they are____________.

　　A) natural B) inexhaustible

　　C) newly-found D) clean

　　3.Biomass,though a renewable energy,mainly causes_______________.

　　A) indoor pollution B) outdoor pollution

　　C) industrial pollution D) agricultural pollution

　　4.In the l970s,some countries began to be concerned about solar energy because of___________.

　　A) economic recession B) sharp rise in oil prices

　　C) reduced oil production D) increased research funds

　　5.In the hills of the Himalayas,“chakki”are used for_____________.

　　A) purifying water B) keeping animals

　　C) producing power D) exchanging goods

　　6.What is recommended to be used by the remote rural areas with little access to conventional energy sources?

　　A) Small hydropower plants. B) Solar energy heaters.

　　C) Wind power mills. D) Hot spring thermal energy.

　　7.It is mentioned that,between the surface and the depth of the ocean,there are great differences in_____________.

　　A) dissolved substance B) natural resource variety

　　C) marine life species D) water temperature

　　8.After coal oil and natural gases,the fourth most important fuel is_____________.

　　9.ICeland was the first counfry that______________.

　　10.In the conventional power plants,a large quantum of heat is lost in the process of condensing______________.

　　答案详解

　　1.[C][定位]根据题干中的high concentrations of harmful gases查找到第1段第2句。

　　解析：选项C与题干组成的因果关系与原文该句中的因果关系虽然表述不同，但内容相同，因此选项C为本题答案。选项A和选项B是high concentrations of harmful gases造成的结果，而非原因，因此不能选。

　　2.[B][定位]根据题干中的sun,wind，renewable等词查找到第2段第2句。

　　解析：选项B与原文该句中的can never be exhausted同义，为本题答案。选项A和选项C的内容没有在原文提及，选项D不能与题干构成相应的因果关系。

　　3.[A][定位]根据题干中的biomass查找到第2段最后一句。

　　解析：原文该句中的a major polluter indoors表明biomass主要引起室内的污染，选项A表达了与此相同的内容，故为本题答案。

　　4.[B][定位]根据题干中的数字1970s查找到第1个小标题Solar Energy下第2段最后一句。

　　解析：在四个选项中，只有选项B在原文该句中提及，其他选项都是无中生有。

　　5.[C][定位]根据题干中的大写名词Himalayas和专有名词“chakki”查找到第2个小标题Hydro Power下第2段第1句。

　　解析：原文该句以居住在喜马拉雅山的人们为例说明人们很早就开始“利用水力发电”了，因此，本题应选C。

　　6.[A][定位]根据题干中的remote rural areas和conventional等词查找到第2个小标题Hydro Power下第4段首句。

　　解析：原文该句中的It指代hydro power，该句还是围绕“水力发电”这一话题，由此可排除B、C和D选项，正确答案为A。

　　7.[D][位]根据题干中的surface，depth，ocean等词查找到第3个小标题Energy From the Sea-Ocean Thermal,Tidal and Wave Energy下首段末句。

　　解析：在原文该句中，只有选项D的内容有提及，其他内容均没有原文依据，因此选项D为本题答案。

　　8.[biomass]

　　[定位]根据题干中的coal，oil，gases和fourth等词查找到笫4个小标题Biomass下第2段末句。

　　解析：空白处应为名词词组。题目只是将原文的主语和表语的位置倒转，由此可见，原文中的主语biomass为本题答案。

　　9.[used geothermal hot water]

　　[定位]根据题干中的专有名词Iceland查找到第5个小标题Geothermal Energy下末段末句。

　　解析：空白处应为定语从句的谓宾部分。原文该句中的pioneered表明冰岛是首个使用地热温泉的地方，在回答问题的时候，注意that后应该是定语从句的谓语，由于事情发生在l943年，该谓语动词应为过去式。

　　10.[the low-pressure steam]

　　[定位]根据题干中的conventional power plants和quantum of heat等词查找到最后一个小标题Co-generation下第2段首句。

　　解析：空白处应为名词词组。在原文该句中，condensing后面并没有带任何宾语，但该段末句中的the low-pressure... is not condensed提示了首句中condensing的宾语应该是该句开头的the low-pressure steam，这也就是本题答案。

　　参考译文

　　可再生能源

　　在上个世纪人们看到，消耗不可再生能源对环境造成的损害比任何其他人类活动都大。[1]从煤炭、原油等化石燃料中产生的电能使大气中积聚了高浓度的有害气体，这反过来导致了许多人们今天需要面对的问题，如臭氧层的减少以及全球气候变暖等。汽车污染也是个主要问题。

　　因此，替代性的能源非常重要，与当今的世界密切相关。[2]这些能源(如太阳能和风能)用之不竭，因此称为可再生能源。它们减少了排放物，并且可以就地利用。它们的使用可以在很大程度上减少化学污染、辐射污染和热污染。作为可行的清洁能源，它们用之不尽，具有突出的优势，还被祢为非常规能源。[3]尽管生物作为可再生能源是室内污染的主要来源，但大多数可再生能源基本上不污染环境，因而被看做是清洁能源。

　　太阳能

　　太阳能是遍布最广的随地可用的能源。它不属于任何人，因此可以免费使用。它也是非常规能源中最重要的能源，因为它无污染，因而有助于减轻温室效应。

　　自从史前时代起人们就开始使用太阳能了，不过，其使用方式极为简单。1970年以前，在一些国家人们为了更有效地利用太阳能而做了一些研发工作，但大多数的研发工作主要停留在学术研究上。[4]20世纪70年代石油价格急剧上涨后，有些国家为了利用太阳能开始展开广泛的研发工作。

　　我们把衣服挂到太阳底下晒干，就是在利用太阳能。同样地，太阳能电池板吸收太阳能为煮饭烧水提供热能。这样的设备如今市场上已有销售.正在为家庭和工厂所使用。

　　我们还可以利用太阳能满足对电力的需求。通过太阳能光电板。太阳辐射可以直接转化为直流电。这种电可以直接使用，也可以在电池中储存起来。这样储存起来的电能就可以在夜晚使用。

　　水电

　　水电是最好、最廉价、最清洁的能源之一，虽然建造大坝带来了许多环境和社会问题。但小水坝就不存在这些问题。在这个国家，这实际上是最早为人所知的可再生能源之一(从20世纪初开始)。

　　[5]事实上，在过去的几百年里，居住在喜马拉雅山的人们一直都在利用水磨(或称为chakki)来磨小麦。小水电站除了没有污染问题，也不存在大型项目所带来的种种问题和矛盾-----大水坝影响了住在河岸的成千上万居民的生活，破坏了大面积的森林，并带来地震的危险。

　　地球变暖的危险使得人们通过了新的环境立法，这些新的立法使小水电厂产生的电能更加具有实际价值。这些小水电可以独立地为偏远乡村地区供电。在偏远地区建设小水电的实际挑战在于有效地推销电能并收回电费。为了可持续发展.应该鼓励当地企业使用这种电力。

　　[6]这是一种具有巨大潜力的技术，它可以利用水资源向难以采用常规能源的偏僻乡村地区提供电力。它还避免了大型水利工程对环境所带来的负面影响。

　　海洋能源——海洋热能，潮汐能和波浪能

　　6000万平方公里的热带海洋吸收的太阳辐射平均相当于2450亿桶石油的能量。科学家们觉得，如果这种能量可以得到开发的话，就可以为热带国家以及其他国家提供巨大的能源。利用这种能源的过程叫做“海洋热能转换”。[7]它利用海洋表面海水和大约lOOO米深处的海水的温差来推动热力发动机来发电。

　　人们还从波浪和潮汐中获得能量。在一些国家，比如日本，波浪或海洋能量推动的小规模发电机被用来向标记航道的浮标提供电能。

　　生物能

　　生物能源是种可再生能源，来自各种人类活动或自然活动的含碳废弃物。它有许多来源，包括木材工业的副产品、农作物、森林中的原材料、生活垃圾的主要部分以及木头。

　　生物能源不会给大气增加二氧化碳，因为它用作燃料焚烧时释放的碳和在生产过程中吸收的碳一样多。这种能源的优势是，可以利用目前焚烧化石燃料的发电厂的同样设备来发电。[8]生物能源是一种重要的能源，世界范围内，其重要性仅次于煤炭、石油和是然气。

　　传统上时生物能源的利用远远超出它在现代社会的利用程度。在发达国家，生物能源现在变得再次重要起来，被用于辅助供热、发电。此外，生物能源作为一种家庭和社区供热设施的清洁热源现正益发重要。事实上，在芬兰、美国和瑞典等国，人均使用的生物能比在印度、中国或亚洲其他国家都多。

　　地热能

　　我们居住在两大能源之间：地表下是滚烫的岩石，天上是太阳。我们的祖先知道地热的价值，他们在温泉里沐浴，用温泉煮东西。如今我们意识到，这种能源拥有更广泛的应用前景。

　　地板很热，利用地热能(希腊语中表示“来自地球的热”)是可能的。这些地方包括那些有火山、温泉和间歇泉的地方，还包括海洋水底下的甲烷。在一些国家，比如在美国，人们从地底下的热水池中把水抽出来给房子供暖。

　　利用地热能发电的历史可以追溯到20世纪早期。有50年的时间里只有意大利在利用地热发电，其他地方的人们过了很久才渐渐地对这种技术感兴趣。[9]1943年，首先是冰岛开始着手开发地热温泉。

　　热电联产

　　热电联产是指利用一种燃料同时产生两种形式的能量。其中一种能量一定是热能，另一种能量可以是电能，也可以是机械能。在传统的发电厂，燃料在锅炉里燃烧以便产生高压蒸汽，蒸汽推动涡轮，涡轮又通过蒸汽轮机推动交流发电机发电。废汽通常凝结成水，又回到锅炉里。

　　[l0]因为低压蒸汽含有大量的热能，这些热能在蒸汽凝结的过程中损耗了，因此传统发电厂的热效率只有大约35%。在热电联产的发电厂却可以达到很高的效率水平，在75%-90%之间。[10]这是因为从涡轮冒出的低压废汽并不用来冷凝成水，而是用来为工厂或房屋供暖。

　　因为热电联产可以同时满足供电、供热的需求，它还有其他一些优点：可以为工厂大量节省成本：因为减少了燃料的消耗，可以减少污染物的排放。