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BEST IELTS General Reading Test 540
IELTS GENERAL READING TEST 540 – PASSAGE – 3
IELTS GENERAL READING TEST – 540
READING PASSAGE – 3
Solar Energy
A. The increasing need for sustainable and renewable sources of energy to replace oil, coal and gas has led to rapid improvements in the design of systems for gathering the greatest source of energy easily available to humanity – the sun. Despite great interest in these solar power systems, a great deal of research and promotion is still needed: in 2008 they accounted for less than 0.02% of global power generation.
B. The sun’s energy can be harnessed in a number of ways, including the direct conversion of its light energy into electricity by the use of photovoltaic cells. Many householders and businesses in developed countries have now installed photovoltaic solar panels on their roof spaces and in some regions are even feeding power back into a country’s electrical grid systems and receiving income or reduced power bills in return.
IELTS General Reading Test
C. A less well-known method of harnessing solar energy on a large scale is that of solar thermal (heat) energy, or STE. This method is based on a principle obvious to all – that the sun’s energy heats air and other materials such as stone, water, or cement. This method has in fact been in use in some form since ancient Roman times. Stone chimneys, heated by the sun, were used as a way of drawing air through buildings to provide ventilation. Such systems are still in use in traditional building designs in the Middle East.
D. Contemporary researchers in many countries including the USA, Germany, China, Spain and Australia are working on a variety of technologies to utilise STE. One attraction is that STE does not require any fuel and generates almost no pollutants. This is not to say that there are no costs in STE: all renewable technologies require significant inputs in research and development and capital infrastructure costs. But proponents of STE and other renewables argue that the costing of current fuel sources ignores their environmental impacts such as the contribution to global warming and the long-term costs associated with that. Hence the interest in developing sustainable long-term STE systems.
IELTS General Reading Test
E. STE systems are often divided into three basic types, that is low-, medium- and high- energy. In the first two, the main aim is to collect the sun’s energy directly in water storage systems on roofs, to heat water for a variety of household purposes. One interesting experimental design by Harold Hay in the 1960’s uses a water storage bladder on the roof, with a moveable cover. In hot weather, the roof bladder stores heat rising from the building during the day, and when uncovered, releases it to the atmosphere at night. When heating is required, the cover is removed in daytime to absorb heat, and replaced at night so that heat is radiated back into the building.
F. The most exciting developments for large-scale power generation require high- temperature systems which concentrate the sun’s heat (CSP, or concentrated solar power). These systems are obviously more suited to large areas of relatively empty desert. Temperatures up to 600-800oc can be achieved in these plants. The heat is then used in various ways to drive turbines which generate electricity. When combined with methods of storing the heat and releasing it at night, CSP has the potential to replace traditional fossil fuels as a way of generating power available 24 hours a day for the basic needs that we take for granted.
IELTS General Reading Test
G. Several designs for CSP use massive arrays of ground-level mirrors to reflect the sun’s heat and turn water into steam. Another design uses a tower (a Solar Updraft Tower) covering a massive area, allowing air heated by the sun to rise through it and turn large turbines to produce electricity.
H. Issues with all CSP designs include the huge area of land required for the mirrors or towers, and the height of updraft towers, which could reach up to 750 metres in one ambitious European project. Even though in experiments in the USA one solar dish design managed to convert 31% of the solar energy falling on it into electricity, in a typical STE plant much of the land used is not actually covered in equipment and producing power, and so conversion rates are closer to 2.5%.
IELTS General Reading Test
Questions 29 – 35
The text “Solar Energy” has eight paragraphs, A – H. Choose the correct heading for paragraphs B – H from the list of headings below. Write the correct number, i – x.
i. Environmental problems with renewable energy systems
ii. Solar thermal energy for heating and cooling
iii. Possibility of uninterrupted power supply from solar
iv. Overall contribution of solar to world energy production
v. Solar energy benefits the nation and the individual
vi. Widespread attention to the importance of investment in STE
vii. Problem with large-scale solar plants
viii. Research funding for solar energy
ix. Early uses of solar thermal energy
x. Different technologies for concentrating solar heat
IELTS General Reading Test
Questions 36 – 40
Do the following statements agree with the information given in the text above? In boxes 36 – 40 on your answer sheet, write:
TRUE If the statement agrees with the information
FALSE If the statement contradicts the information
NOT GIVEN If there is no information on this
IELTS General Reading Test
36. Photovoltaic cells can only be set up on homes and small businesses.
37. The building costs for solar thermal energy plants are low.
38. In CSP systems, the sun’s energy is indirectly used for heating domestic water.
39. CSP systems are too dangerous to be used near cities.
40. USA-based commercial CSP systems are now turning around 30% of sunlight into electricity.
IELTS General Reading Test
IELTS General Reading Test
ANSWERS
29. V
30. IX
31. VI
32. II
33. III
34. X
35. VII
36. NOT GIVEN
37. FALSE
38. TRUE
39. NOT GIVEN
40. FALSE
IELTS General Reading Test