Text 1

Energy　

by Terru Bell

    All forms of energy are important, whether man-made like electricity, or natural like wind-power. Basically, it is energy that makes the world go round. But, what are the different forms of energy? How are they formed? Can we find and develop new sources of energy? Questions like these are discussed in the following passage.

    The sun is the most important source of energy that the earth has. It gives out energy in the form of light and heat to plants or animals or people and helps them to grow. Any changes in the heat produce wind and rain. As the plants receive energy from the sun, they give out oxygen, which is necessary for human and animal life. Human beings also take in energy from the sun but this alone is not enough for a person to live. People also need other forms of energy which they get by eating plants and meat of animals.

    Finding the power of fire was an important step in the changing and growing use of energy. It was probably discovered by accident when the sun made something burn-perhaps a dry tree in a hot summer. Soon fire began to be used as a source of energy. There were many things in the world which would burn and they could be found easily. There were plenty of bushes and trees and there were also pieces of black rock which would also burn; this black rock was coal. There were also pools of oil which burned.

    All these things which burn in the air are called fuels and are all natural materials.

    A lot of coal was found on the earth many years ago but most of the coal could only be found under the ground. The reason for this is that coal was made by trees which died millions of years ago. The trees sank into mud which was carried along by rivers; and the wood slowly changed into coal. The coal was buried deep in the ground by the movement of rocks, earth and plants which pressed down on it and formed different layers above it. Coal is the same as wood, therefore; but it burns much longer and produces much more heat so it is more useful as a source of energy than wood.

    Oil was probably made from very small sea animals. When they died, they sank to the bottom of the sea. The weight of heavy rocks pushed all the dead bodies together and after many millions of years, they changed into oil. Like coal, oil is found deep in the earth, often in places which are very difficult to reach. Men drill into the ground to get oil.

    Natural gas is also a fuel; it will burn in air. It is very often found together with oil sources, caught between the oil and the rocks. At first, when oil was discovered under the ground, the gas was not considered useful. It was seen only as one more problem in the search for oil and was burned off so that the oil could be reached more quickly. But after many years of burning off the gas, it was realized that the gas was also a useful fuel. Then gas pipelines were built under the ground so that the gas could be taken to different parts of the country. Gas can also be taken in liquid form in large lorries. But this is dangerous because if the liquid gas escapes and reaches the air it can explode.

    A large area of the world is covered with water, most of which is always moving. It did not take very long before people began to make use of the power of water. When water falls, the force which is created is quite powerful and it is possible to turn a large wheel by this force. This wheel will then turn another wheel which can carry out a certain job such as moving two stones together to cut corn into small pieces.

    Hydro-electricity (water power) is probably the most-used form of energy given by nature. There are many countries which use hydro-electricity: India, Pakistan, Egypt, America, Australia and Uganda all produce power from water and then use the water again on the land in order to grow food. More than 90% of the electricity used in Sweden, Norway, Portugal, Switzerland and some South African states is produced by hydro-electric generators .

    Apart from water power, people found they could make use of the force of the wind to create power and windmills were built. The wind turned the windmill which then turned a large stone in order to make flour out of corn.

    Both water and wind power are cheap forms of energy and they are easily available but they can only create a small quantity of energy. Another problem is that these forms of energy can only be produced when the weather is right.
    All the sources of energy discussed here are natural forms of energy, all created directly or indirectly by the sun. The natural fuels, such as coal, oil and gas, are more useful than wind or water power because the amount of energy they produce is greater. However, burning natural fuels is not the best way to use them, as much of the energy is wasted: it disappears into the air. But scientists found that they can put fuels to better use by turning them into a different form of energy.

    For example, if coal is heated in a container without any air, it does not burn but changes into another form of fuel called coke. Coke produces less smoke than coal and is very good for heating but it is quite difficult to start it burning. As the coal is changed into coke, a gas is also produced. This gas is called coal gas and can be stored in large containers called gas-holders and used for heating and lighting. So, from one fuel, two other more useful forms of energy have been created. Not all coal, however, is suitable to be made into coke.

    The oil which is found under the ground comes to the surface as crude oil. This means that the oil is in its natural state and has not been changed in any way. It is, in fact, a mixture of different sorts of oils which can be separated from each other. To do this, the crude oil is heated and cooled many times and different parts can then be taken away. Some sorts of oils are used to heat buildings or to put into machines so that they work efficiently. Others are especially suitable forms for transport. Probably the most important function of coal and oil is to heat water for the steam engine, or steam turbine where electricity is produced. Electricity can then be supplied to all parts of the country through cables.

    A fuel such as coal or oil heats water in a boiler and steam is produced. The steam is under great pressure and turns the blades of a turbine. As the turbine turns, electrical energy is produced through a generator. The electricity is then sent out to houses and factories.

    Instead of using steam to turn the blades of the turbine, electricity can also be produced by the force of water which falls onto the turbine blades. The amount of water which falls must be very great, however, and so dams are built to give the necessary amount of water. Some dams produce large amounts of electricity.

    An atom is something very small which cannot be seen by the eye. But it exists; in fact everything known on the earth is made out of atoms. Atoms join together to form gases, liquids and solids. All atoms contain energy. About 35 years ago, scientists began to make use of the energy source which is found in atoms. They are very small but it is possible to break them into smaller pieces. When this is done, great heat is produced; this heat can be used to produce electricity in the same way as the heat produced by burning fuels is used. The heat which is given off by the atoms, however, is very much greater than any other form of fuel we know and so more electricity can be made. In Britain and in many other parts of the world, electricity from atoms, called nuclear energy, provides one more source of power.

( 1,353 words )              TOP

课文一

能源
泰瑞·贝尔

    无论是电这样的人造能，还是风一类的自然能，各种形式的能都很重要。从根本上说，正是这些能推动世界不断运转。能有哪些不同形式？它们之间的分别是如何形成的？人类能不能发掘出新的能源呢？下文将讨论这些问题。

    太阳是地球最重要的能源。它以光和热的形式向动植物和人类提供能，促进万物生长。热量变化，就会产生风和雨。植物在从太阳那里吸收能的同时释放出人和动物需要的氧气。人类从太阳那里直接汲取能量，但这无法满足基本生活需求。人类还需要通过食用动植物来获得其他形式的能量。

    火的发现使人类在不断改进、加强能利用的过程中迈出了重要的一步。一个夏天，在阳光的酷晒下，枯树枝燃烧起来，于是火被人类十分偶然地发现了。很快火开始作为一种能源被广泛使用。在地球上，很容易找到大量可燃物质：茂密的灌木丛，大片的树林，还有可燃的黑石块，也就是煤，以及大量的石油！

    所有这些可以在空气中燃烧的物质都叫燃料。这些燃料都是自然物质。

    很多年以前，地球上发现了大量的煤，但其中大部分都埋在地表以下，这是因为煤是从几百万年前死去的树木演变而来的。树木沉陷到泥土中，随河流漂荡，渐渐地就变成了煤。岩层、土壤和植被的运动将煤向下挤压，并在其上方形成不同的地层。这样，煤就被深埋在地下了。可见，煤与木头实际上是一样的。不过，煤燃烧得更为持久，释放的能量也比木头多得多。因此，同为能源，煤的用处比木头要大些。

    石油可能来自微小的海洋生物。海洋生物死亡以后，它们的尸体向海洋底层沉淀下去。海底硕大的石块把它们挤压到一起，经过几百万年就转化成石油。石油和煤一样，是在地底深层被发现的，而且常常出现在一些人类很难到达的地方。因此，人们要向地下钻孔以开采石油。

    天然气也是一种燃料，它可以在空气中燃烧。人们在发现石油资源的同时，往往会在石油层和岩石层之间发现天然气。起初，人们只开采石油，认为天然气毫无用处，反而是石油开采的又一障碍。为了更快采到石油，人们将天然气白白烧掉。这种做法持续了很久。后来，人们渐渐意识到天然气也是一种大有用处的燃料。于是开始在地下修筑管道，把天然气运输到各地。还将天然气以液态形式装在大卡车里运送。但这样做有些危险，因为一旦液化气泄漏，接触到空气，便能引发爆炸。

    地球表面很大一部分为水覆盖，而这些水多为流动的活水。人们很早就开始利用水能。倾泻而下的水流会产生极大的力量，完全可以推动一只大水轮。这只水轮又带动另一只轮子转动，这样就可以干很多活儿了。比如，带动两块碾石将玉米碾成碎粒。

    各种天然能中，水力应用也许最为广泛。很多国家都采用水力发电的形式，如：印度、巴基斯坦、埃及、美国、澳大利亚和乌干达。各国均先从水资源中获取能量，然后再用它灌溉耕地，生产粮食作物。在瑞典、挪威、葡萄牙、瑞士和南部非洲一些国家，超过90%的电能都是由水力发电机产生的。

    人们发现除了水力，风力也可以用来创造能量，于是风车出现了。风带动风车旋转，风车又驱动石块将玉米磨成面粉。

    水力和风力都是成本低廉、极易获取的能源形式。它们容易得到，但是创造的能量很小。还有一个问题是二者均只有在天气适宜的情况下才能产生。

    在此谈及的种种能源都属于自然形态能，均由太阳以直接或间接的方式生成。煤、石油、天然气等天然燃料所产生的能量比水力和风力巨大得多，故具有更大的用途。然而，燃烧天然燃料并非能源利用的最佳途径。因为在燃烧的过程中，许多能量被释放到空气中，造成了能量浪费。科学家发现，将燃料转换成其他形式的能，然后再加以利用，可以提高其使用价值。

    例如：把煤放入真空容器并加热。这时，煤并不会燃烧，而是转化成一种叫做焦炭的燃料。燃烧时，焦炭比煤产生的烟要少，因此非常适用于采暖装置，但是它不易点燃。在煤转换成焦炭的同时产生了一种气体，被称作煤气。煤气可以被贮存在叫做煤气罐的大容器里，用来取暖和照明。这样，从一种燃料中便产生了两种不同形态的能源，但并非所有的煤都适于制成焦炭。

    地底探测到的石油被带到地表时仍处于原油状态，即处于未经任何改变的、天然的状态。事实上，它是一种由多种可分离的油类共同构成的混合物。对原油进行多次加热、冷却的反复操作，其不同组成成分就会被一一分离。其中一些油可用于建筑物供暖或为机器的高效运作提供动力。有些则尤其适用于交通运输。煤和石油最重要的功能是为蒸汽发动机和涡轮机中的蓄水加热，以产生电力。接下来，电力通过电缆被运送到四面八方。

    燃料（如煤、石油）加热锅炉中的水，产生蒸汽。承受高压的蒸汽推进涡轮机的叶片转动。涡轮机转动时，电能便通过发电机产生了。然后电被传送到各家各户和工厂。

    不采用蒸汽的话，水流冲泻到叶片上也可产生电能。这要求有足够的水量。于是水坝应运而生，为发电提供必需的水量。不少水坝可以产生大量的电能。

    原子体积微小，人们无法用肉眼来观察它。可它的的确确存在。事实上，地球上一切可知的物质都是由原子构成的。原子聚合起来，形成气体、液体和固体。所有原子都包含能量。大约35年前，科学家开始利用原子中发现的能。原子如此微小，却还可分解成更小的微粒。原子裂变会产生巨大的热量。通过与燃料发电相似的方式，这种热量也可用来生产电能。不过，与我们所知的任何其他燃料相比，原子所释放出的热能要大得多，因而也能产生更多的电能。在英国和其他很多地区，由原子产生的电能，即原子能，已成为又一大能量来源。

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Text 2

Energy in the Future
by Terry Bell

    Great sources of energy are needed if governments want to develop industry and make life more comfortable. However, fuels which are used to produce energy at the moment will soon run out. It seems certain that people will have to depend on nuclear power as the source of energy. But a lot of people do not want this form of energy; they think it is dangerous and so would like some other source of power. Many suggestions have been made; some of them are not very practical but others could be used successfully.

    People who are against nuclear power would rather use the forces of nature, for example the wind, the sea, the rivers and the sun. It is strange to think that these sources of energy were used long ago for windmills or for watermills but then were almost forgotten. Hydro-electricity is probably the most used form of energy supplied by nature. Yet only a small part of the water energy which could be used is indeed used. In countries such as Britain, America, Canada and Russia, there are great possibilities for developing hydro-electricity but only a small number of generators have been built.

    Hydro-electricity cannot be developed in certain countries, however, because mountains or hills are needed to give the necessary force to the water as it falls. More than three-quarters of the earth is covered by the sea, which is always moving. The movement of the water depends on the moon which pulls at the earth. The sea moves first in one direction and then back again; this movement backwards and forwards is called the "tide".
In some parts of the world the tide is very strong and water moves very quickly. It is possible to produce electricity by using the forces of tides to turn the blades of a turbine. This source of power is called "tidal energy". It is surprising to find that only one country in the world produces energy in this way: France.

    The sea can provide energy in other ways. The movement of waves is quite different from the movement of tides. Waves are caused by winds and storms. Each wave moves across the surface of the ocean with an up and down motion. Think of the sea on a stormy day. You can see the energy of the waves.

    One way of using the movement of waves as source of energy is to build a Cockerell raft. This is actually a series of rafts. They move up and down on the waves. This movement is made into pressure, which is used to produce electricity. There are several other ways of using wave power. But they are still in the early stages. There are no commercial schemes yet.

    Another way we can get energy from the sea is to use the power from under the oceans. Sunshine and its energy is absorbed by the oceans, and stored in them. Scientists are now looking for ways to use this energy.

    One possibility is to use the difference in temperature between the warm surface of the sea and the colder layers of water underneath. This can be used to generate electricity. Underwater cables then can carry the electricity to the land.

    Power plants like this are called Ocean Thermal Electric Conversion plants (OTEC). The best seas for this sort of energy are the Caribbean and the Pacific. There, the temperature difference between the surface of the water and the colder layers can be as much as 4.4 C.

    Another natural source of energy is wind power. Wind is produced by the heating and cooling of the earth; some countries have more wind than others because of great changes in the heat. Britain is a good example of a country with strong winds for many months of the year. Some parts of Britain are especially windy and in these places energy from the wind could be generated most easily. In the north of Scotland, for example, plans were made to build a large number of windmills. Each windmill would be 24 metres high with three blades, each 7 metres long. With enough windmills it would be possible to generate power for the whole of Scotland. However, the number of windmills which would have to be built and the high cost of the plan means that this is not very practical. Probably a cheaper source, such as nuclear energy, will be used. But wind power has not been forgotten completely. Work is going on in France, the USA and Russia to try to develop a low-cost windmill.

    In some parts of the world, large amounts of hot water and steam come out of the ground at great speed. This is because there are lakes of water deep down inside the earth. It is very hot indeed deep down in the earth and so the water is heated; steam is produced which forces its way to the earth's surface. The hot water and steam which shoot into the air are called geysers and can be found in America, New Zealand and Iceland. In New Zealand and Iceland the energy produced by the steam is used for power stations. Geothermal energy, as it is called, is a cheap source of energy. After the power stations have been built there are no further costs for the electricity supply. Only a few countries have geysers but it is also possible to produce energy of this sort by drilling holes deep into the ground and pouring water down the pipes so that it becomes so hot as to produce steam.

    The sun is the most powerful source of energy known on the earth. More energy is produced by the sun than the world could ever use. If the energy from the sun could be caught and used to make electricity, then the energy crisis would disappear and there would be a cheap, never-ending source of energy without any danger to human life. During the last few years, solar energy has been used to heat water and make steam to drive a turbine for electricity. This is done by using mirrors to make the sunlight very strong. This system works very well in some countries with a lot of sunshine. In Europe, where the sun is not always very strong, the cost of making electricity from solar energy is not practical for the amount of electricity produced. But it is possible to heat enough water for a family to use each day for washing, by building metal plates into the roof of the house. Even the sunlight in Britain is strong enough to heat water in pipes behind the metal plates. This warm water then flows from the water taps in the house. In this way other forms of fuel can be saved. During the next few years a lot of new designs for solar energy will be invented and introduced into people's homes.

    This form of solar energy and a fuller development of wind energy together with more hydro-electric power are ways in which the fuel problems could be solved. At the moment, however, most countries seem happy to develop plans for nuclear power stations. But one question which some people are asking is this: is it right to continue living as people do now, developing industry, wasting fuels and building everything bigger and more powerful than before, without thinking of the possible dangers? Or is it better to change ideas about industrial progress? At the moment people waste very much of what they have or of what they produce. They waste their fuel supplies by burning up energy carelessly; they waste materials which are produced and throw them away; they buy more products which are then also thrown away. However, a few scientists in Britain have decided to save energy by doing something about all these waste products. They have found a way to make good oil from waste products, especially from waste plastic. At the moment they are still testing the oil but there is hope that the new oil will be suitable for driving engines and for heating.

(1,380 words )                TOP

课文二

未来的能源

泰瑞·贝尔

    政府要发展工业，并带给人民更为舒适的生活，拥有巨大的能源是先决条件。然而，目前用来提供能量的燃料很快就会用光。显然，人们得依靠核能作为能源。但是很多人认为核能很危险。他们想使用核能之外的能源。人们提出了很多建议，有些不甚实用，但也有些颇为可行。

    反对使用核能的人宁愿使用自然能源，如风、海洋、河流和太阳。想起来有点奇怪，这些能源很久以前就应用在各种磨坊上，可后来却几乎被完全遗忘了。事实上，水力发电是人们利用自然力得到能源的最普遍的方式。但是，可用的水能中，只有很少一部分真正被人类利用。在英国、美国、加拿大、俄罗斯等一些国家，利用水力发电的可能性很大。但这些国家都只有极少量的水力发电机。

    不过，由于山脉稀少，水流不能获得足够的冲击力，一些国家根本无法开发水力资源。超过四分之三的地表为流动的海水覆盖。海水的流动是由月球对地球的引力引起的。海水先向一个方向流动，再向反方向流回，这种来回的运动叫做海潮。世界上有些地方海潮很大，水流湍急。可以通过海潮的力量来带动涡轮机发电。这种能源叫做潮汐能。令人惊讶的是，世界上只有法国在用这种方式产生能量。

    海洋还以其它方式提供能量。海浪的运动与海潮的运动不同。海浪由风暴引起。每一朵浪都会在海面上经历无数个一起一伏的运动过程。想象一下暴风雨中的大海，就能了解海浪的能量。

    利用海浪能的方法之一是建造一个考克尔瑞尔筏。事实上，它是随着海浪上下浮动的一组筏。这种浮动产生的压力被用来发电。还有几种别的方法来利用海浪能源，但都是刚刚起步，还没形成商业性的开发计划。

    另外一种开发海洋能源的方法是利用海洋深处的动力。海洋吸收并储存了太阳光及其能量。科学家们正在寻找利用这种能源的方法。

    利用洋面和洋底之间的温差发电也不失为一种可能。水下电缆可以将电输送到陆地。

    这种发电站被称为海洋电热转换站。加勒比海和太平洋最容易通过这种方式发电，因为水表与低温层的温差高达4.4摄氏度。

    风力也是一种自然能源。地球上的冷热变化形成了风。一些国家由于温度变化大，风也较多。英国就是如此，一年中好几个月都刮大风。有些地区风尤其大，就很容易利用风力发电。在苏格兰北部，曾经拟订过这样一个计划：造许多许多的风车，高24米，带有三个七米长的桨片。只要有足够的风车，供应整个苏格兰的用电不成问题。但是，所需风车数量之多，要投入的成本数额之大，都说明这个计划不太现实。相对廉价的能源， 如核能，更可能被采用。但风力并未被彻底遗忘。在法国、美国和俄罗斯，人们仍在努力工作，试图开发出成本低廉的风车。

    在世界某些地区，会有大量热水和蒸汽快速溢出地表，那是因为地层深处存在着地下湖。地层深处温度极高，因此地下湖处于一种持续加热的状态。产生的蒸汽会冒出地面。这些喷涌出来的热水和蒸汽被称作天然喷泉。美国、新西兰和冰岛都有这种天然喷泉。在新西兰和冰岛，这种蒸汽的能量常被发电站采用。人们称之为地热能。它是一种廉价能源。一旦建起了发电站，就不再需要任何其它成本投入了。尽管只有一些国家有天然喷泉，但是要获得这种能量是可能的。可以在地面钻个洞，深入地底。将水导入管道，使其变热来产生蒸汽。

    地球上为人所知的能源中，太阳能是最为巨大的。它所提供的能量远远超出了人们的需求。如果来自太阳的能量都能被人类捕获并用来发电的话，能源危机就会消失得无影无踪。太阳能廉价，无害，取之不尽，用之不竭。过去几年中，太阳能被用来加热水，以及产生水蒸气来带动涡轮机发电。方法是用镜子集中太阳光，以增加其强度。这种方法在光照较强的国家很适用。但是在欧洲，阳光并不总是很强。由于太阳能所生产的电量与所花费的成本不成比例，这种方法并不实用。但是用太阳能烧水还是很划算的。在屋顶上安装一些金属板就可以提供全家人每天所需的热水。即使在英国，阳光也足以加热金属板背面水管里的水。加热后的水再流向屋内的水龙头。这样，其它燃料就省下来了。在今后的几年里，会有许多新方法、新发明走入千家万户，以便我们更好地利用太阳能，。

    水力发电、风能和太阳能的充分开发和利用，都是解决燃料问题的良策。但是，现在大多数国家都在全力发展核电站。很多人都想问：人类是否应该继续发展工业、浪费燃料、把任何事物都构建得比以前更宏伟更有气势，而全然不顾各种隐患？还是应该改变关于工业进步的一些看法？人类浪费了大量资源和产品。他们不珍惜能源，结果浪费了大量燃料。他们不珍惜产品，结果浪费了大量资源。他们购买超出所需的物品，最后又统统抛掉。一些英国科学家决定通过废物利用来节约能源。他们已经找到了一种利用废物产油的方法，尤其是从废弃的塑料制品中提炼油。现阶段，他们仍在测试这种方法，但这种新型油有望被用来驱动引擎和加热。

（刘 霞译）       返回