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The
Second Sought - After Renewable Energy
Since early 5000 B.C, it is stated in the world history
that human kinds have been harnessing the energy of the wind, for example to
propel boats along the Nile River. By 200 B.C, rather simple windmills in China
were used to pump water, while vertical-axis windmills with woven reed sails
were grinding grain in Persia and the Middle East.
Eventually, new ways of using the wind energy spread around the world. People
in the Middle East used windmills extensively in the 11th century. They used
windmills for food production. Such technology was then adopted by the returning
merchants and crusaders and carried it back to Europe. The Dutch refined the
windmill and adapted it for draining lakes and marshes in the Rhine River Delta.
Later in the 19 th century, when the settlers took this technology to the New
World, they began using windmills to pump water for farms and ranches, and then,
to generate electricity for homes and industry.
In the early era of world industrialization, which started in Europe and later
in America, when the steam engine replaced European water-pumping windmills,
another technology was developed. Commonly called wind turbines,
these machines appeared in Denmark as early as 1890. In 1940s, the largest wind
turbine of the time began operating on a Vermont hilltop known as Granpas
Knob. The turbine, rated at 1.25 megawatts in winds of about 30mph, fed electric
power to the local utility network for several months during World War II.
Today, as the world of modern technology is expanding massively, more and more
research is being carried out on the wind energy. It has also become the worlds
fastest-growing technology.
As for Asian region, such technology is unfortunately not suitable as the region
is hidden from the strong wind blow, compared to other regions. According to
the director of Research Management Centre of the Malaysian National University
(UKM), Prof. Dr. Mohd Yusof Othman, based on the research conducted on the wind
energy here, the speed of the wind blowing in this country is only at 3 metre
per second, while the speed of the wind needed to generate the electricity power
is at least 5 metre per second.
In certain places, Prof. Dr. Mohd Yusof said the wind is blowing seasonally,
compared to Europe and the United States.
A wind turbines machine that could generate electricity power for 1 megawatt
(1,000 kilowatt) has been developed in a Western country.
Thus, for these countries, especially the Scandinavian countries, where consistency
of wind speed and direction is more predictable, wind power is able to produce
more energy compared to the solar energy.
Prof. Dr. Mohd Yusof is however optimistic that as time goes by, with the latest
development on research done on such technology, people will soon realise the
great potential of wind energy to generate electricity and accept it for the
use of basic utilities as it is also environmentally friendly.
Nonetheless, he added that in overseas, such technology is getting more popular
with more countries using the wind turbines to generate electricity power.
On the other hand, the Public Works Department (JKR)s research and development
unit (RDU)s engineering assistant, Sydney Wee, said, in Sarawak, wind
energy is only use for small scale at specific selected sites where wind turbine
may be installed as complimentary power storage, which is for battery charging
in combination to solar photovoltaic system.
Potential areas for such technology which however still under further field
study include Teluk Melano at Tanjung Datu, Bario and Ba Kelalan Highlands
in the interior.
Despite that wind power tends to get cheaper as the capacity increases but vary
if areas of distribution to consumers involved long distant of physical transmission
lines and maintenance.
It is learnt that Sarawak rural community (20% at present are without power)
has been eager to have power supply extension ever since post independence.
The villages readily accept any forms of power generation either from grid or
small scale embedded system.
As long as they (the rural folks) get electricity for lightings and basic
needs, they are not bothered with how government delivers the services,
Wee said.
He also disclosed that RDU is now going into secondary research application
on evolving technology on hybrid system that can be developed for local site
condition. This would give the government more choices and options to deliver
these services to the rural areas that are not covered by grid extension.
Meanwhile, based on an international graduate research in wind energy, it is
expanding globally at a rate of 30% per annum. This means, it is the fastest
growing energy sector worldwide. Research into the subject has increased leading
to improvements in design, development and deployment.
However, despite the increasing popularity of wind energy, there are some advantages
and disadvantages such as explained below:
How Do The Wind Turbines Work
A wind turbine works the opposite of a fan. Instead of using
electricity to make wind, like a fan, wind turbines use wind to make electricity.
The wind turns the blades, which spin a shaft, connects to a generator and makes
electricity.
Types of Wind Turbines
Modern wind turbines fall into two basic groups, which are;
The horizontal-axis variety
having two or three blades (the two blades are operated downwind turbine,
while the three blades operated upwind, with the blades facing the wind.
The vertical-axis design, like the eggbeater-style Darrieus model, named
after its French investor
Understanding the Term Wind Energy
or Wind Power
The terms wind energy describes the process by which the wind is used to generate
mechanical power or electricity. It converts the kinetic energy in the wind
into mechanical power. This mechanical power can be used for specific tasks
(such as grinding grain or pumping water), or a generator can convert this power
into electricity.
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WIND ENERGY
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Advantages
Wind energy is a clean fuel source as it is fuelled by the wind.
It doesn't pollute the air like power plants, which rely on combustion of
fossils fuels, for example, coal or natural gas. The wind turbines do not
produce atmospheric emissions that cause acid rain or greenhouse gasses.
Wind energy relies solely on the renewable power of the wind, which
can't be used up. It actually a form of solar energy (winds are caused by
the heating of the atmosphere by the sun, the rotation of the earth, and
the earth's surface irregularities).
It is one of the lowest-priced renewable energy technologies available
today, costing between 4 and 6 cents per kilowatt-hour, depending upon the
wind resource and project financing of the particular project.
The wind turbines can be built on farms or ranches, thus benefiting
the economy in rural areas, where most of the best wind sites are found.
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Disadvantages
Wind power must compete with conventional generation sources on a
cost basis. Depending on how energetic a wind site is, the wind farm may
or may not be cost competitive, even though the cost of the wind power has
decreased dramatically in the past ten years, the technology requires a
higher initial investment than fossil-fuelled generators.
The major challenge is that the wind is intermittent and it does
not always blow when electricity is needed.
Its resource development may compete with other uses for the land
and those alternative uses may be more highly valued than electricity generation.
Although its environmentally clean compared to the conventional power
plants, there is some concern over the noise produced by the rotor blades,
aesthetic (visual) impacts, and sometimes birds have been killed by flying
into the rotors. |
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