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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-fueled power station, and
produce 1.5 per cent of the state’s electricity.
Nevertheless, in the US, 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
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 standardized 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 organization 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.
Questions 10 - 14
10. Which one of the statements is true?
a) Cost was a big factor in preventing the development of wind power
b) Wind power has developed steadily since the 1970s.
c) Wind power can provide enough electricity for the United States
d) Some US states are powered solely by wind
11. What is the general view of wind energy in the United States?
a) very positive
b) it can only provide small amounts of energy
c) it will reduce global warming
d) very negative
12. Which of these factors has not contributed to the reduced cost of wind energy?
a) state subsidies
b) economies of scale
c) standardization of design
d) more efficient maintenance
13. Wind turbine designs ...
a) are already very good
b) are expected to improve in the future
c) will be much more efficient in the future
d) are good for the environment
14. Wind energy is more developed in Europe than the USA