ppt

1. UNIT 3
Wind Energy Systems and Current
technologies in wind energy

2. History of Wind Energy
 Until the late nineteenth century windmills would only produce mechanical
power for their tasks such as grinding grain or pumping water.
 With the creation of electricity, windmill makers found that windmills could be
attached to a generator and used to create power for heating and lighting.
 The first windmill used to produce electric energy was created in 1888 by
Charles F. Brush.
 By the end of the nineteenth century there were over 30,000 windmills in
Europe. They were used for more than just pumping water and grinding grain,
people used them to run saw mills and other industrial plants.
 These windmills needed to produce 500 revolution per minute in order to power
a generator.

3.  From the 1930’s to the 70’s coal and oil were relatively inexpensive and wind
energy lost its popularity in America though windmills were used in many
other countries throughout the world
 In 1973 America was affected by the Arab oil embargo. This caused
focus to turn toward wind power.
 The U.S. Federal Wind Energy Program was established in 1974.
 By the late 1980’s it was becoming very difficult to attract funding for wind
energy because people did not believe that wind power could be strong
enough to produce the same amount of power as oil.
 Modern wind power is a strong option for alternative energy, and its rich
history proves it can be used effectively
History of Wind Energy

4. Wind Energy is an indirect form of solar energy which can be used continuously
unlike solar energy
Wind energy classified in two types
1.- Planetary winds
2.- Local winds
Planetary winds are cause due to greater heating of earth’s surface near the
equator as compared to solar heating near the south & north poles.
Local winds are caused due to differential heating of land & water in coastal
areas these are due to uneven heating in hills and mountains along the slopes.
Wind is a form of solar energy. Winds are caused by the uneven heating of the
atmosphere by the sun, the irregularities of the earth's surface, and rotation of the
earth. Wind flow patterns are modified by the earth's terrain, bodies of water, and
vegetative cover. This wind flow, or motion energy, when "harvested" by modern
wind turbines, can be used to generate electricity.
Concept of Wind Energy

5. Wind Energy as renewable energy resource
Wind energy is a form of solar energy. Wind energy (or wind power) describes the process by
which wind is used to generate electricity. Wind turbines convert the kinetic energy in the
wind into mechanical power. A generator can convert mechanical power into electricity.
Mechanical power can also be utilized directly for specific tasks such as pumping water.
Wind Energy basics
Wind is caused by the uneven heating of the atmosphere by the sun, variations in the earth's
surface, and rotation of the earth. Mountains, bodies of water, and vegetation all influence
wind flow patterns. Wind turbines convert the energy in wind to electricity by rotating
propeller-like blades around a rotor. The rotor turns the drive shaft, which turns an electric
generator. Three key factors affect the amount of energy a turbine can harness from the wind:
wind speed, air density, and swept area.
Global Wind Energy contribution
At the end of 2019, worldwide installed wind power capacity was 623 GW. Wind-generated
electricity met nearly 4% of global electricity demand in 2015, with nearly 63 GW of new
wind power capacity installed. Wind energy was the leading source of new capacity in
Europe, the US and Canada, and the second largest in China. In Denmark, wind energy met
more than 40% of its electricity demand while Ireland, Portugal and Spain each met nearly
20%.

6. Components of Wind Turbine

7. Wind turbines are used to generate electricity from the kinetic power of the
wind.
Wind turbines convert the kinetic energy in the wind into mechanical power.
This mechanical power can be used for specific tasks ( a generator can
convert this mechanical power into electricity)
The energy in the wind turns two or three propeller-like blades around a rotor.
The rotor is connected to the main shaft, which spins a generator to create
electricity.

8. Main components of wind turbine are shown below:

9. Main components of wind turbine
Rotor Blades:
Converts kinetic energy of wind into rotational energy of shaft that is connected to nacelle. As
wind passes through the blades, a pressure differential is created between the upper and
lower surface of blade which creates a lift that is perpendicular to the direction of wind.
The WTG consists of three blades madeof glass fibre-reinforced plastic; the length of the
blades is 37.5 meter.
The blades are directly bolted to the hub.
Hub
The hub is fixed to the rotor shaft which drives the
generator through
a gearbox. The blades are directly bolted to the hub and
hence are controlled by
the help of motors installed inside the hub.

10. Nacelle:
Nacelle is a casing that holds Drive shaft, gearbox and generator, yaw Motor drive,
brakes, anemometer and controller.
The nacelle is made of fiber-rein forced plastic and designed in a way to protect
internal components against various ambient conditions. It also
ensures adequate noise dampening.

11. Shaft: transfers the rotational energy of rotor into generator . Shaft
which spins a generator to create electricity
 Gearbox: converts the low speed shaft of rotor to a high speed shaft connected to
generator.
 Gearboxes are made up of cast steel with one planetary two spur gear stages.

12. •Wind power generators convert wind energy
(mechanical energy) to electrical energy.
•The generator is attached at one end to the wind
turbine, which provides the mechanical energy.
•At the other end, the generator is connected to
the electrical grid.
•The generator needs to have a cooling system to
make sure there is no overheating.
Generator:
produces electricity of medium voltage through electromagnetic induction

13. Yaw drive : New technology
Yaw system rotates the turbine to keep it in the direction of wind for maximum output.
The yaw drive is an important component of the horizontal axis wind turbines' yaw system.
The yaw system comprises of geared motors and brakes. The yaw drive is used to keep
the rotor facing into the wind as the wind direction changes.

14. Brakes: are used to stop the turbine in case of high wind speed to protect the blades and
power overloading. It can also be done by changing the Pitch of blades.

15. Controller :
monitors the entire system and controls all the operation.

16. Anemometry System
The main function of the anemometry system is to accurately measure and record Wind Speed,
Wind Direction, Ambient Temperature, Humidity and other necessary information relevant to the site
conditions. This information is monitored and transmitted at the same time to many set locations.
The anemometry system comprises of two Wind Masts, Wind Mast is mounted with a Data Logger
installed at 80 meters height, equivalent to the turbine height.
These data loggers are calibrated in accordance with applicable standards;

17. Tower: Tower holds the entire structure at height.
The tower height of every WTG is 80 meters, equipped with internal tower
ladder along with safety harness & elevator. The tower supports the nacelle
assembly which holds the hub along with the blades.

18. Electrical system:
It takes the electricity from top to the bottom of the tower . The installed Wind turbines use
Asynchronous generator whose shaft is connected with a gear box which is coupled with
Hub blades. The WTG produce 690 Volts, which after synchronization thru a frequency
converter is stepped up to 22kV. It is then sent to a substation where it is stepped up
through power transformers to 132kV

19. Electrical Layout:
The installed Wind turbines use Asynchronous generator whose shaft is connected with a gear box
which is coupled with Hub blades. The WTG produce 690 Volts, which after synchronization thru a
frequency converter is stepped up to 22kV through Generator, Step up transformer installed with
each turbine. Each WTG is connected with its own Ring Main Unit switchgear. The voltage produced
by each WTG is fed into system thru Ring Main unit switchgear is interconnected with other RMUs by
underground power cables and fed into MV substation at the site.
The 22Kv is then stepped up through power transformers up to 132kV & then power is evacuated into
132kV national Grid.

20. Auxiliary Plant Facilities
Earthing System
The earthing system is erected together with the foundation.
Safety for persons: The ring earthing reduces the shock hazard voltage for persons being near the
tower foundation during a lightning stroke.
Operational safety: The deep earthing guarantees a low and stable earth resistance for the whole
earthing system.
Lightning protection
The lightning and overvoltage protection for the overall system follows the concept of lightning
protection zones.
The wind turbine is equipped with a complete external and internal lightning protection system
considering a direct lightning stroke. to the ground.
Fire protection
Most components of the wind turbine generator system are predominantly metal. This applies, for
example, to the tower, the machine supports, shaft, gear unit, hydraulic unit, brake, generator, clutch,
drives, etc.
A temperature sensor is installed in the machine house and measures the temperature inside the
machine house. If a certain limit value is exceeded, a warning message is sent automatically to the
remote monitoring office and the system is automatically shut down.

21. Advantage and Disadvantage of Wind Power Plant
The wind blows day and night, which allows windmills to produce electricity
throughout the day. (Faster during the day)
Non-Polluting Resources : Wind energy has no cost, renewable source. It is a
source of clean non-polluting.
Cost Issue : Wind cost are much more competitive with other technologies
because there is no need of fuel to purchase and minimal
operating expenses. Although wind power has decreased its cost dramatically.
Supply and Transport Issue : It is a big issue that wind energy cannot
stored and does not always blow when electricity is needed, but wind
generated electricity can be stored ,if batteries are used ,
and further good wind sites are located in remote location which is far from
that area where electricity are required.

22. Environmental Concern :
Although wind power plants have little impact on the environment as compared
to fossil fuel plants ,there is some concern over the noise produced by
rotor blade and birds and bats are also killed by flying into the
rotor .
Sound from Wind Turbines
- Increasing tip speed  less sound
- The closest neighbor is usually 300 m  experiences almost no noise
• Environment study revealed that power lines are a much greater danger to birds than the
wind turbines.
• Some birds even nest on cages on Wind Towers.