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Non-traditional Sources of Energy
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It is known that much is being done in the world today for the development of non-traditional sources of energy. Now we are using traditional power sources, that is, oil, natural gas, coal and water power with the consumption of more than 50 billion barrels per year. It is evident that these sources are not unlimited. That's why it is so important to use such renewable sources of energy as the sun, wind, geothermal energy and others.
Research is being carried out in these fields. One of the most promising researches is the development of power stations with direct transformation of solar energy into electricity on the basis of photo effect. It was Russia that was the first in the world to develop and test a photoelectric battery of 32,000 volts and effective area of only 0.5 square meters, which made it possible to concentrate solar radiation.
However, the efficiency of solar power station is considerably reduced because of the limited time of its work during the year. But it is possible to improve the efficiency of such stations by developing different combinations of solar power stations and traditional ones – thermal, atomic and hydraulic. It is planned that plants working on the energy of the solar heat provided by the sun will be built on a larger scale.
In Kamchatka there are geothermal power stations operating on hot water-steam mixture from the depths of about a kilometer. In some projects water is supposed to be heated by the warmth of mountains at a depth of four-five km.
That different wind energy plants are being built is also well-known. They can be small (of several kilowatts) and large powerful systems.
It is important that all these advances in developing new sources of energy and improving the old ones help to solve the energy problem as a whole and they do not have negative effects on the environment.
Vocabulary
| renewable | восполняемый |
| oil | нефть |
| coal | каменный уголь |
| wind | ветер |
| however | однако |
| solar | солнечный |
| hydraulic | гидравлический |
| depth | глубина |
| warmth | тепло |
| environment | окружающая среда |
| it is evident | очевидно |
| on a larger scale | более масштабно |
| as a whole | в целом |
Ответьте на следующие вопросы:
Ø What traditional power sources are we using now?
Ø Why is it so important to use non-traditional renewable sources of energy? What are they?
Ø What reduces the efficiency of a solar power station?
Ø How can this problem be solved?
Ø What are advantages of using non-traditional sources of energy?
Выполните письменный перевод текста, пользуясь словарём.
In Search of New Sources of Energy
Two concrete blocks on the bottom of the sea off the north coast of Scotland are all that is left of the world's first attempt to build a commercial wave-power plant1.
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When the large yellow 2-megawatt generator was wrecked by waves that were meant to power it, hope died. But the dream of using wave power to generate endless 'clean' electricity hasn't faded.
Wave power is not easily obtained. Researchers had a number of other devices ready to be tested in the water. They learnt lessons from the power plant mentioned above which was wrecked, just as they had from other disappointments. They revised their designs and created new ones. Today, the prospects for wave power have never looked better2. For the first time, independent analysts think that the electricity which could be produced from wave power will cost less than that produced from new nuclear and coal-fired stations.
At least3 15 wave-power generators are planned across the globe: nine in Europe, four in the Far East, one in the US and one in India. All are robust, realistic designs, shaped by years of trial and error4.
Some international experts on wave power think it could supply more than 10 per cent of the world's electricity and help to solve shortages of drinking water by desalinating sea water. Inspired by this prospect, researchers in Britain have been in the vanguard of 5 wave power research.
Примечания
1. wave - power plant – электростанция, работающая на энергии морской волны;
2. have never looked better – никогда не выглядели более обнадеживающими;
3. at least – по крайней мере;
4. shaped by years of trial and error – созданные в результате многолетних испытаний и ошибок;
5. to be in the vanguard of – быть в авангарде, возглавлять.
UNIT 2: Conductivity and Superconductivity
Text 2A
1. Выпишите значения данных слов, пользуясь словарём. Обратите внимание на произношение:
conductor n., insulator n., flow п., v.,resist v.,length п.,employ v.,pipe п.,short a.,copper n.,iron п.,socket п.,silver п.,cord п., cover v., rubber n.,glass n.,hence adv., though.
Conductors and Insulators
All substances have some ability of conducting the electric current; however, they differ greatly in the ease with which the current can pass through them. Metals, for example, conduct electricity with ease while rubber does not allow it to flow freely. Thus, we have conductors and insulators.
Substances through which electricity is easily transmitted are called conductors. Any material that strongly resists the electric current flow is known as an insulator.
Let us first turn our attention to conductance that is the conductor's ability of passing electric charges. The four factors conductance depends onare: the size of the wire used, its length and temperature as well as the kind of material to be employed. It is not difficult to understand that a large water pipe can pass more water than a small one. In the same manner, a large conductor will carry the current more readily than a thinner one.
It is quite understandable, too, that to flow through a short conductor is certainly easier for the current than through a long one in spite of their being made of similar material. Hence, the longer the wire, the greater is its opposition, that is, resistance, to the passage of current.
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There is a great difference in the conducting ability of various substances. For example, almost all metals are good electric current conductors, nevertheless, copper carries the current more freely than iron; and silver, in its turn, is a better conductor than copper. Generally speaking, copper is the most widely used conductor. That is why the electrically operated devices in your home are connected to the wall socket by copper wires.
A material which resists the flow of electric current is called an insulator. There are many kinds of insulations used to cover the wires. The kind used depends upon the purposes the wire or cord is meant for. The insulating materials we generally use to cover the wires are rubber, asbestos, glass, plastics and others. Rubber covered with cotton, or rubber alone is the insulating material usually used to cover desk lamp cords and radio cords. Glass is the insulator to be often seen on the poles that carry the telephone wires in city streets. One of the most important insulators of all, however, is air.
Упражнения
I. Найдите в тексте:
Ø английские эквиваленты следующих слов: ток, медь, проводник, сопротивление, способность, протекать, изолятор, покрывать, розетка, проводить (ток), резина, таким образом, отличаться, короткий, в свою очередь, воздух, серебро, железо;
Ø слова, противоположные по значению данным: long, different, thicker, easy, worse.
II. Дайте определения:
Ø подберите готовые определения к данным словам:
current, resistance, socket, cover, flow.
Ø the ability of a substance to stop the flow of an electric current through it;
Ø a place in a wall where you can connect electrical equipment to the supply of electricity;
Ø a smooth, steady movement of liquid, gas or electricity;
Ø to put something over or be over something in order to protect;
Ø a flow of electricity through a wire;
Ø выпишите из текста определения следующих слов: conductor, insulator, copper, rubber, conductance;
Ø выучите наизусть все определения.
III. Ответьте на вопросы, не обращаясь к тексту.
o What is a conductor?
o Are all metals good electric current conductors? What is the most widely used conductor?
o How can you define the word 'conductance'?
o What factors does conductance depend on?
o Is it easier for the current to flow through a short or a long conductor?
o What is a better conductor: copper or iron; silver or copper?
o What is called an insulator?
o What are the most widely used insulators?
o What does the kind of insulator used depend on?
IV. Перескажите текст 2А.
Text 2Б
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