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IELTS Reading Sample
Wind Power in the US
Prompted by the oil crises of the 1970s,
a wind-power industry flourished briefly in the United States. But then
world oil prices dropped, and funding for research into renewable energy
was cut. By the mid 1980s US interest in wind energy as a large-scale
source of energy had almost disappeared. The development of wind power
at this time suffered not only from badly designed equipment, but also
from poor long-term planning, economic projections that were too
optimistic and the difficulty of finding suitable locations for the wind
turbines.
Only now are technological advances
beginning to offer hope that wind power will come to be accepted as a
reliable and important source of electricity. There have been
significant successes in California, in particular, where wind farms now
have a capacity of 1500 megawatts, comparable to a large nuclear or
fossil-fuelled power station, and produce 1.5 per cent of the state's
electricity.
Nevertheless, in the U.S., the image of
wind power is still distorted by early failures. One of the most
persistent criticisms is that wind power is not a significant energy
resource. Researchers at the Battelle Northwest Laboratory, however,
estimate that today wind turbine technology could supply 20 per cent of
the electrical power the country needs. As a local resource, wind power
has even greater potential. Minnesota's energy commission calculates
that a wind farm on one of the state's south western ridges could supply
almost all that state's electricity. North Dakota alone has enough sites
suitable for wind farms to supply more than a third of all electricity
consumed in the continental US.
The prevailing notion that wind power is
too costly results largely from early research which focused on turbines
with huge blades that stood hundreds of metres tall. These machines were
not designed for ease of production or maintenance, and they were
enormously expensive. Because the major factors influencing the overall
cost of wind power are the cost of the turbine and its supporting
systems, including land, as well as operating and maintenance costs, it
is hardly surprising that it was thought at the time that wind energy
could not be supplied at a commercially competitive price. More recent
developments such as those seen on California wind farms have
dramatically changed the economic picture for wind energy. These
systems, like installations in Hawaii and several European countries,
have benefited from the economies of scale that come through
standardised manufacturing and purchasing. The result has been a
dramatic drop in capital costs: the installed cost of new wind turbines
stood at $1000 per kilowatt in 1993, down from about $4000 per kilowatt
in 1980, and continues to fall. Design improvements and more efficient
maintenance programs for large numbers of turbines have reduced
operating costs as well. The cost of electricity delivered by wind farm
turbines has decreased from about 30 cents per kilowatt-hour to between
7 and 9 cents, which is generally less than the cost of electricity from
conventional power stations. Reliability has also improved dramatically.
The latest turbines run more than 95 per cent of the time, compared with
around 60 per cent in the early 1980s. Another misconception is that
improved designs are needed to make wind power feasible. Out of the
numerous wind turbine designs proposed or built by inventors or
developers, the propeller-blade type, which is based on detailed
analytical models as well as extensive experimental data, has emerged as
predominant among the more than 20,000 machines now in commercial
operation world-wide. Like the gas-driven turbines that power jet
aircraft, these are sophisticated pieces of rotating machinery. They are
already highly efficient, and there is no reason to believe that other
configurations will produce major benefits. Like other ways of
generating electricity, wind power does not leave the environment
entirely unharmed. There are many potential problems, ranging from
interference with telecommunications to impact on wildlife and natural
habitats. But these effects must be balanced against those associated
with other forms of electricity generation. Conventional power stations
impose hidden costs on society, such as the control of air pollution,
the management of nuclear waste and global warming. As wind power has
been ignored in the US over the past few years, expertise and commercial
exploitation in the field have shifted to Europe. The European Union
spends 10 times as much as the US government on research and development
of wind energy. It estimates that at least 10 per cent of Europe's
electrical power could be supplied by land-based wind-turbines using
current technology. Indeed, according to the American Wind Energy
Association, an independent organisation based in Washington, Denmark,
Britain, Spain and the Netherlands will each surpass the US in the
generating capacity of wind turbines installed during the rest of the
decade.
Glossary
fossil fuel: coal, oil and natural gas
kilowatt: 1,000 watts; a watt is a unit of power
kilowatt-hour: one kilowatt for a period of one hour
megawatt: one million watts
wind farm: a group of wind turbines in one location producing a large
amount of electricity
wind turbine: a machine which produces energy when the wind turns its
blades
Questions 1 - 5
Complete the summary below using words from the box. Write your
answers in boxes 1-5 on your answer sheet.
NB There are more words or phrases than you will need to fill the
gaps. You may use any word or phrase more than once.
Example
The failure during the late 1970s and early 1980s of an attempt to
establish a widespread wind power industry in the United States resulted
largely from the ...(1)... in oil prices during this period. The
industry is now experiencing a steady ...(2)... due to improvements in
technology and an increased awareness of the potential in the power of
wind. The wind turbines that are now being made, based in part on the
...(3)... of wide-ranging research in Europe, are easier to manufacture
and maintain than their predecessors. This has led wind-turbine makers
to be able to standardise and thus minimise ...(4)... . There has been
growing ...(5)... of the importance of wind power as an energy source.
| criticism |
success |
design costs |
production costs |
failure |
| stability |
operating costs |
fall |
growth |
recognition |
| scepticism |
decisions |
effects |
decline |
results |
|
Questions 6 - 10
Look at the following issues (Questions 6-10) and the list of
implications below (A-C). Match each issue with the correct implication.
Write the correct letter A-C in boxes 6-10 on your answer sheet.
N.B. You may use any letter more than once.
Example
The current price of one wind-generated kilowatt... Answer A
Issues
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6. |
The recent installation of systems taking advantage
of economies of scale ...
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7. |
The potential of meeting one fifth of current US
energy requirements by wind power ...
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8. |
The level of acceptance of current wind turbine
technology ...
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9. |
A comparison of costs between conventional and wind
power sources ...
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10. |
The view of wind power in the European Union ... |
Implications
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A |
provides evidence against claims that electricity
produced from wind power is relatively expensive.
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B |
supports claims that wind power is an important
source of energy.
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C |
opposes the view that wind power technology
requires further development. |
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