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Wind energy

By KUSHAGRA JAIN
Wind in action:

When wind strikes an object, it exerts a force in an attempt to move it out
of the way. Some of the winds’ energy is transferred to the object, in this
case the windmill, causing it to move.
Wind Today!!!
Windmills are used for pumping
water from deep underground.
Modern wind turbine is the result of
design and material advances made
during the 1980s and 1990s, which
enabled wind turbines to become
increasingly efficient.
Today, wind turbines are size same
as the traditional European windmill.
It can generate 250 to 300 kilowatts of
power- a nearly tenfold increase in
efficiency.

History of Wind usage:
 one of the earliest energy resources.
Recorded in history, first to power boats
and grind grain, later to pump water, press
oil, saw lumber and make paper.
Windmills were mentioned at the
beginning of Islamic civilization (7th century).
Windmills were developed in Persia and
used paddles made of bundled reeds.
Egyptians may have been the first to go up
the Nile river around 4th century B.C,
powered by wind.
Ancient Chinese used vertical axis
windmills to grind grain and pump water.
Windmills were introduced to Europe by
the crusaders around 1300 A.D
*windmills used for pumping water.
Wind turbines convert 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 mechanical
power into electricity.
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, which
The energy in the wind turns two or three
connects to a generator and makes electricity.
propeller-like blades around a rotor. The rotor
is connected to the main shaft, which spins a
generator to create electricity.
Wind turbines are mounted on a tower to
capture the most energy. At 100 feet (30
meters) or more above ground, they can take
advantage of faster and less turbulent wind.
A Wind Turbine
Pitch

A Wind Turbine

Rotor

Blades

Generator

Tower
Specific components
Description
Wind turbine

2. Is the rotor. The rotor provides the
blades to rotate.
4. This is brake. It’s very important to
have a brake in a wind turbine, if
something is wrong or it is going to
fast. Then it will brake and stop the
wind turbine. 5. is a low-speed shaft, it
goes into a big cog wheel and this goes
into a smaller cog wheel. The small
cog wheel rotates faster than the big
cog wheel.
7. This is the generator. It’s almost
like a generator in a car.
13. It’s a yaw draw, it makes the wind
turbine rotate in the wind direction.
15. Is the tower. The entrance is
placed in the bottom of the tower
How the does a wind turbine works?
Wind turbines operate on a simple principle:
The energy in the wind turns the propeller-like blades
around a rotor. The pitch of the blades makes optimum
use of the wind direction.
The rotor is connected to the main drive shaft, which
spins a generator to create electricity.
Wind turbines are mounted on a tower to capture the
most energy. At 30 metres or more above ground, they
can take advantage of faster and less turbulent wind.
Wind turbines can be used to produce electricity for a
single home or building, or they can be connected to an
electricity grid for more widespread electricity
distribution.
Advantages and Disadvantages???
Advantages:
No pollution.
Lowest prices renewable resources
Don’t produce atmospheric
emissions that cause acid rains and
green house effects.
Disadvantages:
Depending on how energetic a wind site is, the wind
farm may or may not be cost competitive.
Wind energy cannot be stored (unless batteries are
used)
Good wind sites are often located in remote locations
Wind resource development may compete with other
uses for the land and those alternative uses may be more
highly valued than electricity generation.
sometimes birds have been killed by flying into the
rotors
Jaisalmer wind farm
[The 2 largest off shore wind farm in the world]
Onshore advantages






A regular onshore turbine
last for around 20 years
Normally it takes about 2-3
months before the wind
turbine has paid itself back.
This also includes the
energy, which were used to
produce, install, maintain
and remove the wind
turbine.
Cheaper foundation
Cheaper integration with
electrical-grid network

Onshore disadvantages





Wind turbines are noisy
Each one can generate
the same level of noise
as a family car
travelling 70 mph
Some people thinks
that the large towers of
wind turbines destroys
the view of the
landscape
Onshore or offshore?
Offshore advantages

Offshore disadvantages

• A offshore wind turbine is • More expensive to built
stronger than a onshore
• More difficult to
turbine. It lasts around
maintain and access
25-30 years, and produces
about 50 % more energy
than a onshore turbine.
• When a strong wind blows,
it produces around 3-5
MW per hour.
• Higher and more constant
wind speed
London Array
[Worlds largest on shore wind farm]
General advantages
• Wind energy is friendly to the surrounding
environment, as no fossil fuels are burnt to
generate electricity from wind energy
• Wind turbines requires less space than
average power stations.
• When combined with solar electricity, this
energy source is great for developed and
developing countries to provide a steady,
reliable supply of electricity
General disadvantages
• The main disadvantage regarding wind
power is down to the winds unreliability
factor. In many areas, the winds
strength is not enough to support a wind
turbine
• Wind turbines generally produce allot
less electricity than the average fossil
fuelled power station, which means that
multiple wind turbines are needed to
make an impact.
Thank you

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Wind Energy

  • 2. Wind in action: When wind strikes an object, it exerts a force in an attempt to move it out of the way. Some of the winds’ energy is transferred to the object, in this case the windmill, causing it to move. Wind Today!!! Windmills are used for pumping water from deep underground. Modern wind turbine is the result of design and material advances made during the 1980s and 1990s, which enabled wind turbines to become increasingly efficient. Today, wind turbines are size same as the traditional European windmill. It can generate 250 to 300 kilowatts of power- a nearly tenfold increase in efficiency. History of Wind usage:  one of the earliest energy resources. Recorded in history, first to power boats and grind grain, later to pump water, press oil, saw lumber and make paper. Windmills were mentioned at the beginning of Islamic civilization (7th century). Windmills were developed in Persia and used paddles made of bundled reeds. Egyptians may have been the first to go up the Nile river around 4th century B.C, powered by wind. Ancient Chinese used vertical axis windmills to grind grain and pump water. Windmills were introduced to Europe by the crusaders around 1300 A.D *windmills used for pumping water.
  • 3. Wind turbines convert 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 mechanical power into electricity. 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, which The energy in the wind turns two or three connects to a generator and makes electricity. propeller-like blades around a rotor. The rotor is connected to the main shaft, which spins a generator to create electricity. Wind turbines are mounted on a tower to capture the most energy. At 100 feet (30 meters) or more above ground, they can take advantage of faster and less turbulent wind.
  • 6. Specific components Description Wind turbine 2. Is the rotor. The rotor provides the blades to rotate. 4. This is brake. It’s very important to have a brake in a wind turbine, if something is wrong or it is going to fast. Then it will brake and stop the wind turbine. 5. is a low-speed shaft, it goes into a big cog wheel and this goes into a smaller cog wheel. The small cog wheel rotates faster than the big cog wheel. 7. This is the generator. It’s almost like a generator in a car. 13. It’s a yaw draw, it makes the wind turbine rotate in the wind direction. 15. Is the tower. The entrance is placed in the bottom of the tower
  • 7. How the does a wind turbine works? Wind turbines operate on a simple principle: The energy in the wind turns the propeller-like blades around a rotor. The pitch of the blades makes optimum use of the wind direction. The rotor is connected to the main drive shaft, which spins a generator to create electricity. Wind turbines are mounted on a tower to capture the most energy. At 30 metres or more above ground, they can take advantage of faster and less turbulent wind. Wind turbines can be used to produce electricity for a single home or building, or they can be connected to an electricity grid for more widespread electricity distribution.
  • 8. Advantages and Disadvantages??? Advantages: No pollution. Lowest prices renewable resources Don’t produce atmospheric emissions that cause acid rains and green house effects. Disadvantages: Depending on how energetic a wind site is, the wind farm may or may not be cost competitive. Wind energy cannot be stored (unless batteries are used) Good wind sites are often located in remote locations Wind resource development may compete with other uses for the land and those alternative uses may be more highly valued than electricity generation. sometimes birds have been killed by flying into the rotors
  • 9. Jaisalmer wind farm [The 2 largest off shore wind farm in the world]
  • 10. Onshore advantages     A regular onshore turbine last for around 20 years Normally it takes about 2-3 months before the wind turbine has paid itself back. This also includes the energy, which were used to produce, install, maintain and remove the wind turbine. Cheaper foundation Cheaper integration with electrical-grid network Onshore disadvantages    Wind turbines are noisy Each one can generate the same level of noise as a family car travelling 70 mph Some people thinks that the large towers of wind turbines destroys the view of the landscape
  • 11. Onshore or offshore? Offshore advantages Offshore disadvantages • A offshore wind turbine is • More expensive to built stronger than a onshore • More difficult to turbine. It lasts around maintain and access 25-30 years, and produces about 50 % more energy than a onshore turbine. • When a strong wind blows, it produces around 3-5 MW per hour. • Higher and more constant wind speed
  • 12. London Array [Worlds largest on shore wind farm]
  • 13. General advantages • Wind energy is friendly to the surrounding environment, as no fossil fuels are burnt to generate electricity from wind energy • Wind turbines requires less space than average power stations. • When combined with solar electricity, this energy source is great for developed and developing countries to provide a steady, reliable supply of electricity
  • 14. General disadvantages • The main disadvantage regarding wind power is down to the winds unreliability factor. In many areas, the winds strength is not enough to support a wind turbine • Wind turbines generally produce allot less electricity than the average fossil fuelled power station, which means that multiple wind turbines are needed to make an impact.
  • 15.