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1. The Use of Solar Energy

The Sun possesses a limitless amount of energy and mankind is looking for different ways to uti1ize it because time will come when we shall not have any other energy but the Sun's. Coal, oil and gas will be used up.

The most primitive device for using the heat of the Sun is the gardener's greenhouse. Usually this device consists of the solar water-heater placed on the roof of the greenhouse and covered with g1ass. The water circulating in it is heated by the Sun, then pumped into a hot-water tank warming the greenhouse. Such a 100 square-metre greenhouse was built in Turkmenia: solar energy is used to grow flowers and vegetab1es all the year round on a commercial basis.

Solar energy is used both for heating houses and for cooling them. For example in Florida many "solar houses" have been built. In these houses some material is used to take it and to keep heat of the Sun and to give it away gradually as required. Water is a good material for the purpose, but Glauber's salt is even more efficient. It melts at a temperature of 90' talking in a large amount of heat which it gives back when it turns into crystals again. Another interesting material is gravel in the walls of the house, which it keeps warm on sunless days. In Ashkhabad there are many houses cooled with the help of solar energy. Ten children's institutions in the same city have been equipped with showers. They look like any other showers, except that water for them is heated by the Sun to a temperature of 70' C on the south sides of the houses. As Turkmenia gets more than 180 sunny days each year (as many as Egypt and California) solar showers can be used from early spring till late autumn.

2. The Use of Solar Energy (2)

A solar plant to distil underground water has been operating for several years in the Central Kara-Kum Desert. Its initial capacity was three cubic meters of water daily. After the evaporator has been installed the area had been increased to one hectare, the capacity went up four-fold. This is enough to provide water for a large number of sheep.

One group of scientists from Turkmenian Academy of Sciences has made experiments on solar energy concentrators and gathered enough data on possible potential performance of solar electric stations generating cheap electricity in the Kara-kum Desert. As a result a solar furnace deve1oping temperatures of 3000 (in a sunray foca1 point) has been built. Electricity generated by this furnace costs a half of that generated by thermal stations. In the near future Kara-kum will become a large producer of cheap e1ectricity. The amount of solar energy per square meter here is equivalent to the energy got from burning 200 kg of the best coal.

The most efficient way of generating electricity from sunlight, however, seems to be the "solar battery". The first solar batteries were semiconductor crystals of germanium or silicon similar to those used in transistors. When the sun lights such a crystal, an electric current is generated. Since their first demonstration in 1954 the solar battery has been extensively developed and used in one of the greatest achievements of mankind – in space research on boards space ships, space rockets and sputniks. Solar batteries are very good for the purpose because of their 1ong 1ife.

In 1985 the first solar power-station will be put into operation in the Crimea. its power being 5 MWt – such was the power of the first Soviet atomic power-station in Obninsk.