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					                 The Wind Power

       The Report of The Wind Power Workgroup




      RENEWABLE ENERGIES: MY HOUSE IN THE YEAR 2007 PROJECT

                                  15 Şubat 2009
Written by Neşe Marmara; Oğuz Bölük; Bahattin Tozyılmaz; Alexander Piller; Di Rocco
 Marlyne; Fléjo Alan; İrem Karataş; Melis Tekant; Marta Ros; Patricia Rubio; Posso
                             Caroline; Rémy Severac
                              INDEX

                              WHAT IS THE W IND POWER? ..............................................................................................2
                              THE HISTORY OF THE W IND POWER ...................................................................................3
                              TECHNICAL DETAILS ..........................................................................................................5
                                THE PLACEMENT ...........................................................................................................5
                                  ONSHORE PLACEMENT ...............................................................................................6
                                  NEAR-SHORE PLACEMENT .........................................................................................6
                                  OFFSHORE PLACEMENT .............................................................................................7
                                  AIRBORNE PLACEMENT ..............................................................................................8
                                TECHNICAL ASSEMBLY ...................................................................................................9
                                  CALCULATING THE POWER OF THE WIND ......................................................................9
                                EXAMPLE TYPES .......................................................................................................... 11
                                  ENERCON E-70........................................................................................................ 11
                                REPOWERING .............................................................................................................. 11
                              MAPS ............................................................................................................................. 12
                                FRANCE (FRANCE) ....................................................................................................... 13
                                TURKEY (TÜRKIYE) ...................................................................................................... 14
                                SPAIN (ESPAÑA) .......................................................................................................... 15
                                GERMANY (DEUTSCHLAND) .......................................................................................... 16
                              WINDFARM MODELS ........................................................................................................ 17
                                NEUTSCHER HÖHE ...................................................................................................... 17
                                HAVMOLLE PARK ......................................................................................................... 17
                              ECONOMICAL SCOPE ....................................................................................................... 18
                              ENVIRONMENTAL SCOPE ................................................................................................. 19
                                CO2 EMİSSİONS AND POLLUTİON ................................................................................... 19
                                ECOLOGİCAL FOOTPRİNT .............................................................................................. 19
                                LAND USE.................................................................................................................... 19
                                IMPACT ON WİLDLİFE .................................................................................................... 20
                                  BİRDS ..................................................................................................................... 20
                                  BATS ....................................................................................................................... 21
                                  FİSH ........................................................................................................................ 21
                                OFFSHORE OCEAN NOİSE ............................................................................................. 21
                                SAFETY ....................................................................................................................... 21
                                AESTHETİCS ................................................................................................................ 22
                              ADVANTAGES & DISADVANTAGES ..................................................................................... 24
                                ADVANTAGES .............................................................................................................. 24
                                DISADVANTAGES ......................................................................................................... 24
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                              FREQUENTLY ASKED QUESTIONS ..................................................................................... 25
                              REFERENCES & SOURCES ............................................................................................... 29




   1
                              The Wind Power
                      The Report of The Wind Power Workgroup

What is the Wind Power?
Wind energy is an alternative source of electricity. This technology harnesses the power of
the wind. Specifically, the wind spins turbines which powers generators whose main task is
to produce electricity.

The wind is one of the safest and cleanest sources of renewable energy today. The concept
is similar to those of <http://www.monsterguide.net/how-to-build-a-windmill.shtml"
target="_blank">windmills used for crushing grains or for irrigation. However, in the case of
wind turbines, the force of the wind on the blades creates rotational motion; this motion is
used to generate electricity.

Wind is just a simple movement of air due to differences in temperature between air near the
land's surface and air over bodies of water. In sunny days, the land receives lots of energy in
the form of radiation from the sun. This unequal distribution of energy heats up the air above
land in a much faster rate than the air found over bodies of water.

This creates a difference in temperature between the two masses of air, one is warmer (air
over land) and one is cooler (air over bodies of water). Naturally, as the air becomes warmer,
it expands and rises higher up the atmosphere. It then forces the cooler air on top of bodies
of water to take its place. As the cooler air moves in to take the place of the rising air, wind is
created.

Wind power is the conversion of wind energy into useful form, such as electricity, using wind
turbines. In windmills, wind energy is directly used to crush grain or to pump water. At the
end of 2007, worldwide capacity of wind-powered generators was 94.1 gigawatts.[1]
Although wind currently produces just over 1% of world-wide electricity use, it accounts for
approximately 19% of electricity production in Denmark, 9% in Spain and Portugal, and 6%
in Germany and the Republic of Ireland (2007 data). Globally, wind power generation
increased more than fivefold between 2000 and 2007.

Wind power is produced in large scale wind farms connected to electrical grids, as well as in
individual turbines for providing electricity to isolated locations.

Wind energy is plentiful, renewable, widely distributed, clean, and reduces greenhouse gas
emissions when it displaces fossil-fuel-derived electricity. The intermittency of wind seldom
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creates insurmountable problems when using wind power to supply a low proportion of total
demand, but it presents extra costs when wind is to be used for a large fraction of demand.




                                                                                                      2
                              The History of the Wind Power
                              Since ancient times, man has harnessed the power of the wind to provide motive power for
                              transportation. Likewise, the technique of grinding grain between stones to produce flour is
                              similarly ancient, and widespread. Quite where and when these two came together in the first
                              windmill is unknown, but a likely scenario suggests a Persian origin, from where (tradition
                              has it) the knowledge spread back into Northern Europe as a result of the Crusades.
                              However, since the Persian mills were quite unlike the early European designs it seems just
                              as likely that the adaptation of wind as a power source was independently discovered in
                              Europe, albeit at a later date. (Of course wind was not the first non-human power source
                              applied to the task of grinding corn - it was preceeded by both animal power, and in all
                              probability by water power).

                              European millwrights became highly skilled craftsmen, developing the technology
                              tremendously, and as Europeans set off colonizing the rest of the globe, windmills spread
                              throughout the world. A primary improvement of the European mills was their designer's use
                              of sails that generated aerodynamic lift.

                              The pinnacles of windmill design include
                              those built by the British, who developed
                              many advanced "automatic control"
                              mechanisms over the centuries, and the
                              Dutch (who used windmills extensively to
                              pump water and for industrial uses, as
                              well as to grind grain). The first
                              illustrations (1270 A.D.) show a four-
                              bladed mill mounted on a central post
                              (thus, a "postmill") which was already
                              fairly technologically advanced relative to
                              the Persian mills.

                              The process of perfecting the windmill
                              sail, making incremental improvements in
                              efficiency, took 500 years. By the time the
                              process was completed, windmill sails
                              had all the major features recognized by modern designers as being crucial to the
                              performance of modern wind turbine blades, including 1) camber along the leading edge, 2)
                              placement of the blade spar at the quarter chord position (25% of the way back from the
                              leading edge toward the trailing edge), 3) center of gravity at the same 1/4 chord position,
                              and 4) nonlinear twist of the blade from root to tip (Drees, 1977). Some models also featured
                              aerodynamic brakes, spoilers, and flaps. The machine shown in Figure 4 (which was
                              operating with two of its buddies pumping water about one meter up from one irrigation pond
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                              to another in the Netherlands in 1994) features leading edge airfoil sections.

                              These mills were the "electrical motor" of pre-industrial Europe.

                              Applications were diverse, ranging from the common waterwell, irrigation, or drainage
                              pumping using a scoop wheel (single or tandem), grain-grinding (again, using single or
                              multiple stones), saw-milling of timber, and the processing of other commodities such as
                              spices, cocoa, paints and dyes, and tobacco



   3
                                                 While continuing well into the 19th
                                                 century, the use of large tower mills
                                                 declined with the increased use of steam
                                                 engines.

                                                 So, men have sought other possible uses
                                                 of the wind, including the production of
                                                 electricity

                                                 The first was a three-blades 10 meters in
                                                 diameter with a capacity of 10 kW. His
                                                 speed was 50 rpm. The regulatory
                                                 system was done by using 3 weights. The
                                                 rotor was connected to the engine via a
                                                 multiplier report 1 / 23. The 3 blades were
                                                 braced them. The mat had a height of 15
                                                 meters and it was tie. The windmill was
                                                 replaced by the second because had a
poor performance.

The second windmill was equipped the same as the previous mat but with a whole new
platform, a new pitch commissioned by servo motor and 3 new blades. Its diameter was
10.25 meters, and its speed was up to 75 rpm. The 10 kW engine was replaced by a 12 kW
engine of 750 rpm, which was coupled to a new report multiplier 1 / 8. This turbine was
disassembled because of noise, too fragile mat (at the major rotation speeds), and problems
in the system followed the wind.




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                                                                                               4
                              Technical Details
                                   The Placement
                                   As a general rule, wind generators are practical where the average wind speed is 10
                                   mph (16 km/h or 4.5 m/s) or greater. Usually sites are pre-selected on basis of a wind
                                   atlas, and validated with wind measurements. Obviously, meteorology plays an
                                   important part in determining possible locations for wind parks, though it has great
                                   accuracy limitations. Meteorological wind data is not usually sufficient for accurate
                                   siting of a large wind power project. Site Specific Meteorological Data is crucial to
                                   determining site potential. An 'ideal' location would have a near constant flow of non-
                                   turbulent wind throughout the year and would not suffer too many sudden powerful
                                   bursts of wind. An important turbine siting factor is access to local demand or
                                   transmission capacity.

                                   The most crucial step in the development of a potential wind site is the collection of
                                   accurate and verifiable wind speed and direction data as well as other site
                                   parameters. To collect wind data a Meteorological Tower is installed at the potential
                                   site with instrumentation installed at various heights along the tower. All towers
                                   include anemometers to determine the wind speed and wind vanes to determine the
                                   direction. The towers generally vary in height from 30 to 60 meters. The towers
                                   primarily used in determining site feasibility for potential wind farms are guyed steel-
                                   pipe structures which are left to collect data for one to two years and then usually
                                   disassembled. Data is collected by a data logging device which stores and transmits
                                   data to a server where it is analyzed.

                                   The wind blows faster at higher altitudes because of the reduced influence of drag of
                                   the surface (sea or land) and the reduced viscosity of the air. The increase in velocity
                                   with altitude is most dramatic near the surface and is affected by topography, surface
                                   roughness, and upwind obstacles such as trees or buildings. Typically, the increase
                                   of wind speeds with increasing height follows a logarithmic profile that can be
                                   reasonably approximated by the wind profile power law, using an exponent of 1/7th,
                                   which predicts that wind speed rises proportionally to the seventh root of altitude.
                                   Doubling the altitude of a turbine, then, increases the expected wind speeds by 10%
                                   and the expected power by 34% (calculation: increase in power = (2.0) ^(3/7) – 1 =
                                   34%).

                                   Wind farms or wind parks often have many turbines installed. Since each turbine
                                   extracts some of the energy of the wind, it is important to provide adequate spacing
                                   between turbines to avoid excess energy loss. Where land area is sufficient, turbines
                                   are spaced three to five rotor diameters apart perpendicular to the prevailing wind,
                                   and five to ten rotor diameters apart in the direction of the prevailing wind, to minimize
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                                   efficiency loss. The "wind park effect" loss can be as low as 2% of the combined
                                   nameplate rating of the turbines.

                                   Utility-scale wind turbine generators have minimum temperature operating limits
                                   which restrict the application in areas that routinely experience temperatures less
                                   than −20 °C. Wind turbines must be protected from ice accumulation, which can make
                                   anemometer readings inaccurate and which can cause high structure loads and
                                   damage. Some turbine manufacturers offer low-temperature packages at a few
                                   percent extra cost, which include internal heaters, different lubricants, and different

   5
alloys for structural elements, to make it possible to operate the turbines at lower
temperatures. If the low-temperature interval is combined with a low-wind condition,
the wind turbine will require station service power, equivalent to a few percent of its
output rating, to maintain internal temperatures during the cold snap. For example,
the St. Leon, Manitoba project has a total rating of 99 MW and is estimated to need
up to 3 MW (around 3% of capacity) of station service power a few days a year for
temperatures down to −30 °C. This factor affects the economics of wind turbine
operation in cold climates.

       Onshore Placement
       Onshore turbine installations in hilly or mountainous regions tend to be on
       ridgelines generally three kilometers or more inland from the nearest
       shoreline. This is done to exploit the so-called topographic acceleration. The
       hill or ridge causes the wind to accelerate as it is forced over it. The additional
       wind speeds gained in this way make large differences to the amount of
       energy that is produced. Great attention must be paid to the exact positions of
       the turbines (a process known as micro-siting) because a difference of 30m
       can sometimes mean a doubling in output. Local winds are often monitored for
       a year or more with anemometers and detailed wind maps constructed before
       wind generators are installed.

       For smaller installations where such data collection is too expensive or time
       consuming, the normal way of prospecting for wind-power sites is to directly
       look for trees or vegetation that are permanently "cast" or deformed by the
       prevailing winds. Another way is to use a wind-speed survey map, or historical
       data from a nearby meteorological station, although these methods are less
       reliable.

       Wind farm siting can sometimes be highly controversial, particularly as the
       hilltop, often coastal sites preferred are often picturesque and environmentally
       sensitive (for instance, having substantial bird life). Local residents in a
       number of potential sites have strongly opposed the installation of wind farms,
       and political support has resulted in the blocking of construction of some
       installations.

       Near-Shore Placement
       Near-Shore turbine installations are generally considered to be inside a zone
       that is on land within three kilometers of a shoreline or on water within ten
       kilometers of land. These areas tend to be windy and are good sites for
       turbine installation, because a primary source of wind is convection caused by
       the differential heating and cooling of land and sea over the cycle of day and
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       night. Wind speeds in these zones share the characteristics of both onshore
       and offshore wind, depending on the prevailing wind direction.

       Common issues that are shared within near-shore wind development zones
       are aviary (including bird migration and nesting), aquatic habitat,
       transportation (including shipping and boating) and visual aesthetics. Local
       residents in some potential sites have strongly opposed the installation of wind
       farms due to these concerns.



                                                                                             6
                              Offshore Placement




                              O FFSHORE   W IND TURBINES NEAR   C OPENHAGEN
                              Offshore wind development zones are generally considered to be ten
                              kilometers or more from land. Offshore wind turbines are less obtrusive than
                              turbines on land, as their apparent size and noise can be mitigated by
                              distance. Because water has less surface roughness than land (especially
                              deeper water), the average wind speed is usually considerably higher over
                              open water. Capacity factors (utilization rates) are considerably higher than for
                              onshore and near-shore locations which allows offshore turbines to use
                              shorter towers, making them less visible.

                              In stormy areas with extended shallow continental shelves (such as Denmark),
                              turbines are practical to install — Denmark's wind generation provides about
                              18% of total electricity production in the country, with many offshore wind
                              farms. Denmark plans to increase wind energy's contribution to as much as
                              half of its electrical supply.

                              Locations have begun to be developed in the Great Lakes - with one project
                              by Trillium Power approximately 20 km from shore and over 700 MW in size.
                              Ontario, Canada is aggressively pursuing wind power development and has
                              many onshore wind farms and several proposed near-shore locations but
                              presently only one offshore development.

                              In most cases offshore environment is more expensive than onshore. Offshore
                              towers are generally taller than onshore towers once the submerged height is
                              included, and offshore foundations are more difficult to build and more
                              expensive. Power transmission from offshore turbines is generally through
                              undersea cable, which is more expensive to install than cables on land, and
                              may use high voltage direct current operation if significant distance is to be
                              covered — which then requires yet more equipment. Offshore saltwater
                              environments can also raise maintenance costs by corroding the towers, but
                              fresh-water locations such as the Great Lakes do not. Repairs and
                              maintenance are usually much more difficult, and generally more costly, than
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                              on onshore turbines. Offshore saltwater wind turbines are outfitted with
                              extensive corrosion protection measures like coatings and cathodic protection,
                              which may not be required in fresh water locations.

                              While there is a significant market for small land-based windmills, offshore
                              wind turbines have recently been and will probably continue to be the largest
                              wind turbines in operation, because larger turbines allow for the spread of the
                              high fixed costs involved in offshore operation over a greater quantity of
                              generation, reducing the average cost. For similar reasons, offshore wind


   7
farms tend to be quite large—often involving over 100 turbines—as opposed
to onshore wind farms which can operate competitively even with much
smaller installations.

Airborne Placement
Wind turbines might also be flown in high speed winds at altitude, although no
such systems currently exist in the marketplace. An Ontario (Canada)
company, Magenn Power, Inc., is attempting to commercialize tethered aerial
turbines suspended with helium.

The Italian project called "Kitegen" uses a prototype vertical-axis wind turbine.
It is an innovative plan (still in the construction phase) that consists of one
wind farm with a vertical spin axis, and employs kites to exploit high-altitude
winds. The Kite Wind Generator (KWG) or KiteGen is claimed to eliminate all
the static and dynamic problems that prevent the increase of the power (in
terms of dimensions) obtainable from the traditional horizontal-axis wind
turbine generators. A number of other designs for vertical-axis turbines have
been developed or proposed, including small scale commercial or pilot
installations. However, vertical-axis turbines remain a commercially unproven
technology.




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                                                                                    8
                              Technical Assembly
                              Terminology: Rotornabe= Rotorhub; Gondelnachführung=Yaw Drive;
                              Scheibenbremse = Disc Brake; Lüfter=Ventilator; Blitzableiter=Lightning conductor;
                              Windfahne=Windindicator; Getriebe: Gear Box/transmission; Hauptwelle=MainDrive;
                              Rotorblatt=Rotorblade




                              The power of the wind is transferred to the rotor blades which drive the main shaft of
                              the gearbox. This changes the rotation of the main shaft to the necessary revolutions
                              for the generator which converts the rotations into electric energy. The lightning
                              conductor protects the nacelle against lightning damages. If necessary a disk brake
                              stops the rotor blades, for example during a windstorm…etc. By means of a yaw
                              drive, the nacelle is constantly faced into the wind as the wind direction changes.



                                     Calculating the power of the wind
                                     Part of the kinetic energy of the wind is transformed into rotational energy by
                                     the rotors. These drive an electrical generator which changes the rotational
                                     energy into electricity.




                                     This formula allows to calculate the power of the wind. p stands for air density,
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                                     r is the radius of the rotor, v the wind velocity and t is the time that it takes the
                                     wind to pass through the rotor blades. Example: The air density v averages
                                     1,22 kg/m³, the wind velocity averages 08m/s and the rotor diameter 100 m.
                                     The kinetic energy which passes through the rotor blades averages 2,45 MW.
                                     (4)




   9
With the kinetic energy of the wind and the degree of efficiency of the wind
power station the largest production of energy can be calculated. The degree
of efficiency of all wind power stations averages 59,30%.

With the following formula the power which a wind power station is able to
produce can be calculated:

The degree of efficiency of the wind power station multiplied with the kinetic
energy of the wind results in the maximally producible power. Example-
calculation with the above calculated kinetic energy: Pn=0,593*2,45MW =
1,47MW is the maximum of produced power at 8m/s.

The lower limit of wind velocity for producing of electricity averages 3,5m/s.
Less than 3,5m/s the wind power station is not able to produce electricity
anymore. At more than 25m/s wind velocity the wind power station turns itself
off to avoid damage. The optimum wind velocity averages 12 to16m/s.




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                                                                                 10
                              Example Types
                                     Enercon E-70
                                     Enercon is the German market leader
                                     with a market share of 44%. The wind
                                     power station E-70 has been
                                     developed for locations with higher
                                     wind forcees and has a capacity of
                                     2,3 MW. The diameter of the rotor is
                                     71m. The hight from ground to hub is
                                     between 58 – 113 m with a wind
                                     class 1. That means that this
                                     installation is constructed for wind
                                     speeds of 50 m/s in an extreme case
                                                    or rather an average speed of 10 m/s.

                                                   The system concept is without a gearbox. The rotating direction
                                                   is in a clockwise direction with a speed of approximately 6 – 21
                                                   rotations per minute. The nacelle features 3 rotor blades which
                                                   can be changed individually. The lightning protector is integrated
                                                   in the rotor blades. Generation of electricity is effected by a ring
                                                   generator. As of a wind speed of approximately 28 – 34 m/s the
                                                   installation shuts down.

                                                   Repowering
                                                   Repowering means that old generators with less power are
                                                   replaced by new generators with a better efficiency. Wind
                                                   energy plants constructed in the early 90s have a power output
                                                   of approximately 250 KW, today the most powerful wind energy
                                                   plants have a power output of approximately 5000KW, that is a
                                                   twenty fold raise. The aim is to boost the already installed power
                                                   rating and at the same time minimize the exploitation of
                                                   available locations.

                                                    In this way you can produce fundamentally more power with
                              fewer machines and with that you can release the strain on the environment. A wind
                              park with an old generation of wind energy plants, which produces approximately 18
                              MW, would be a good example for that. If it was repowered it could now produce 39,4
                              MW without any additional windmill. Of course repowering also helps the
                              characteristic landscape, because several wind power plants would disappear.
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                              Legend: Increase of installed power rating: In only 20 years the power rating of wind
                              farms could be increase 100 times. Special SMW plants will multiply the power rating
                              by the factor




11
Maps




       T HE W IND   POW ER   M AP   OF   G ENERAL E UROPE
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                                                            12
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13
                                   France (France)
Turkey (Türkiye)




                W İND S PEED M AP   OF   T URKEY ( AT 100   METERS ABOVE SEA LEVEL )




                                          W İND S PEED ( M / H )



Please click here for more detailed information about Turkey.




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                                                                                       14
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15
                                   Spain (España)
Germany (Deutschland)
This title’s content couldn’t be received from German Team. They were going to send
this part to us via e-mail.




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                                                                                      16
                              Windfarm Models
                                  Neutscher Höhe
                                  An Example of a small
                                  ―wind park‖ is the
                                  Neutscher Höhe in the
                                  Odenwald. 37 private
                                  persons      cooperated
                                  and built 3 wind
                                  installations each with
                                  600 kW at 14,5 m/s.
                                  One installation cost
                                  approximately 600.000
                                  €. The mast of a wind
                                  turbine is approximately 50m high an stands of a 1,8m deep fundament with a
                                  diameter of 12m. The rotor blades have a length of 17m. The wind park was built in
                                  1994/1995 and 2004 was the first year in which a profit was achieved. Every year
                                  approximately 2,1 mio. KWh are delivered which is enough to provide approximately
                                  350 households ( 4 persons) with electricity. Because of the wind park 1320 tons CO2
                                  are saved.

                                  Investors: 37 private persons

                                  Built: 1994/95

                                  Number of wind power stations: 3

                                  Top energy yield of a plant: 600 KW

                                  Costs of a plant: 600.000 €

                                  Annual yield: 2.1 m. kWh

                                  Annual CO2 saving: 1312 tons

                                  Havmolle Park
                                  Location: In front of the southern coast of Lolland in Denmark

                                  Built: 2001-2004

                                  Number of wind power stations: 72

                                  Costs of the plants: 213 m. €
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                                  Performance of a plant: 2.3 megawatt

                                  Performance of all of the plants: 165,6 megawatt




17
Economical Scope
Export markets are growing rapidly. Overseas markets account for about half of the business
of U.S. manufacturers of small wind turbines and wind energy developers. Small wind turbine
markets are diverse and include many applications, both on-grid (connected to a utility
system) and off-grid (stand-alone).

The potential economic benefits from wind are enormous. At a time when U.S. manufacturing
employment is generally on the decline, the production of wind equipment is one of the few
potentially large sources of new manufacturing jobs on the horizon.

AWEA estimates that wind installations worldwide will total more than 100,000 megawatts
over the next decade, or more than $100 billion worth of business. If the U.S. industry could
capture a 25% share of the global wind market through the year 2015, many thousands of
new jobs would be created.




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                                                                                                18
                              Environmental Scope
                                  CO 2 emissions and pollution
                                  Wind power consumes no fuel for continuing operation, and has no emissions directly
                                  related to electricity production. Operation does not produce carbon dioxide, sulfur
                                  dioxide, mercury, particulates, or any other type of air pollution.

                                  It is sometimes said that wind energy, for example, does not reduce carbon dioxide
                                  emissions because the intermittent nature of its output means it needs to be backed
                                  up by fossil fuel plants. Wind turbines do not displace fossil generating capacity on a
                                  one-for-one basis. But it is unambiguously the case that wind energy can displace
                                  fossil fuel-based generation, reducing both fuel use and carbon dioxide emissions.

                                  A study by the Irish national grid stated that "Producing electricity from wind reduces
                                  the consumption of fossil fuels and therefore leads to emissions savings", and found
                                  reductions in CO2 emissions ranging from 0.33 to 0.59 tones of CO2 per MWh.

                                  Ecological footprint
                                  Unlike fossil fuel and nuclear power stations, which
                                  circulate or evaporate large amounts of water for
                                  cooling, wind turbines do not need water to generate
                                  electricity. Leaking lubricating oil or hydraulic fluid
                                  running down turbine blades may be scattered over
                                  the surrounding area, in some cases contaminating
                                  drinking water areas.

                                  Land use
                                  To reduce losses caused by interference between
                                  turbines, a wind farm requires roughly 0.1 square
                                  kilometers of unobstructed land per megawatt of
                                  nameplate capacity. A 200 MW wind farm might
                                  extend over an area of approximately 20 square
                                  kilometers.

                                  Clearing of wooded areas is often unnecessary. Farmers commonly lease land to
                                  companies building wind farms. In the U.S., farmers may receive annual lease
                                  payments of two thousand to five thousand dollars per turbine. The land can still be
                                  used for farming and cattle grazing. Less than 1% of the land would be used for
                                  foundations and access roads, the other 99% could still be used for farming. Turbines
                                  can be sited on unused land in techniques such as center pivot irrigation. The
                                  clearing of trees around tower bases may be necessary for installation sites on
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                                  mountain ridges, such as in the northeastern U.S.

                                  Turbines are not generally installed in urban areas. Buildings interfere with wind,
                                  turbines must be sited a safe distance ("setback") from residences in case of failure,
                                  and the value of land is high. A lakeshore demonstration project by Toronto Hydro in
                                  Toronto has been built.




19
Offshore locations use no land and avoid known shipping channels. Most offshore
locations are at considerable distances from load centers and may face transmission
and line loss challenges.

Wind turbines located in agricultural areas may create concerns by operators of crop-
dusting aircraft. Operating rules may prohibit approach of aircraft within a stated
distance of the turbine towers; turbine operators may agree to curtail operations of
turbines during cropdusting operations.

Impact on wildlife
       Birds
       Danger to birds is often the main complaint against the installation of a wind
       turbine, but actual numbers are very low: studies show that the number of
       birds killed by wind turbines is negligible compared to the number that die as a
       result of other human activities such as traffic, hunting, power lines and high-
       rise buildings and especially the environmental impacts of using non-clean
       power sources. For example, in the UK, where there are several hundred
       turbines, about one bird is killed per turbine per year; 10 million per year are
       killed by cars alone. In the United States, turbines kill 70,000 birds per year,
       compared to 57 million killed by cars and 97.5 million killed by collisions with
       plate glass. An article in Nature stated that each wind turbine kills on average
       0.03 birds per year, or one kill per thirty turbines.

       In the UK, the Royal Society for the Protection of Birds (RSPB) concluded that
       "The available evidence suggests that appropriately positioned wind farms do
       not pose a significant hazard for birds." It notes that climate change poses a
       much more significant threat to wildlife, and therefore supports wind farms and
       other forms of renewable energy.

       Some paths of bird migration, particularly for birds that fly by night, are
       unknown. A study suggests that migrating birds may avoid the large turbines,
       at least in the low-wind non-twilight conditions studied. A Danish 2005 (Biology
       Letters 2005:336) study showed that radio tagged migrating birds traveled
       around offshore wind farms, with less than 1% of migrating birds passing an
       offshore wind farm in Rønde, Denmark, got close to collision, though the site
       was studied only during low-wind non-twilight conditions.

       A survey at Altamont Pass, California, conducted by a California Energy
       Commission in 2004 showed that onshore turbines killed between 1,766 and
       4,721 birds annually (881 to 1,300 of which were birds of prey). Radar studies
                                                                                          The Wind Power | 15.02.2009




       of proposed onshore and near-shore sites in the eastern U.S. have shown that
       migrating songbirds fly well within the reach of large modern turbine blades. In
       Australia, a proposed wind farm was canceled because of the possibility that a
       single endangered bird of prey was nesting in the area.

       A wind farm in Norway's Smøla islands is reported to have affected a colony of
       sea eagles, according to the British Royal Society for the Protection of Birds.
       Turbine blades killed ten of the birds between August 2005 and March 2007,
       including three of the five chicks that fledged in 2005. Nine of the 16 nesting


                                                                                          20
                                     territories appear to have been abandoned. Norway is regarded as the most
                                     important place for white-tailed eagles.

                                     Bats
                                     The numbers of bats killed by existing onshore and near-shore facilities has
                                     troubled bat enthusiasts. A study in 2004 estimated that over 2200 bats were
                                     killed by 63 onshore turbines in just six weeks at two sites in the eastern U.S.
                                     This study suggests some onshore and near-shore sites may be particularly
                                     hazardous to local bat populations and more research is needed. Migratory
                                     bat species appear to be particularly at risk, especially during key movement
                                     periods (spring and more importantly in fall). Lasiurines such as the hoary bat,
                                     red bat, and the silver-haired bat appear to be most vulnerable at North
                                     American sites. Almost nothing is known about current populations of these
                                     species and the impact on bat numbers as a result of mortality at wind power
                                     locations. Offshore wind sites 10 km or more from shore do not interact with
                                     bat populations.

                                     Fish
                                     In Ireland, construction of a wind farm caused pollution feared to be
                                     responsible for wiping out vegetation and fish stocks in the Lough Lee. A
                                     separate landslide is thought to have been caused by wind farm construction,
                                     and has killed thousands of fish by polluting the local rivers with sediment.

                              Offshore ocean noise
                              As the number of offshore wind farms increase and move further into deeper water,
                              the question arises if the ocean noise that is generated due to mechanical motion of
                              the turbines and other vibrations which can be transmitted via the tower structure to
                              the sea, will become significant enough to harm sea mammals. Tests carried out in
                              Denmark for shallow installations showed the levels were only significant up to a few
                              hundred meters. However, sound injected into deeper water will travel much further
                              and will be more likely to impact bigger creatures like whales which tend to use lower
                              frequencies than porpoises and seals. A recent
                              study found that wind farms add 80–110 dB to the
                              existing low-frequency ambient noise (under
                              400 Hz), which could impact baleen whales
                              communication and stress levels, and possibly prey
                              distribution.

                              Safety
                              Operation of any utility-scale energy conversion
The Wind Power | 15.02.2009




                              system presents safety hazards. Wind turbines do
                              not consume fuel or produce pollution during normal
                              operation, but still have hazards associated with
                              their construction and operation.

                              There have been at least 40 fatalities due to
                              construction, operation, and maintenance of wind
                              turbines, including both workers and members of the
                              public, and other injuries and deaths attributed to the

21
wind power life cycle. Most worker deaths involve falls or becoming caught in
machinery while performing maintenance inside turbine housings. Blade failures and
falling ice have also accounted for a number of deaths and injuries. Deaths to
members of the public include a parachutist colliding with a turbine and small aircraft
crashing into support structures. Other public fatalities have been blamed on
collisions with transport vehicles and motorists distracted by the sight and shadow
flicker of wind turbines along highways.

When a turbine's brake fails, the turbine can spin freely until it disintegrates or
catches fire. This is mitigated in most modern designs by aero brakes, variable pitch
blades, and the ability to turn the nacelle to face out of the wind. Turbine blades may
fail spontaneously due to manufacturing flaws. Lightning strikes are a common
problem, also causing rotor blade damage and fires. When ejected, pieces of broken
blade and ice can be thrown hundreds of meters away. Although no member of the
public has been killed by a malfunctioning turbine, there have been close calls,
including injury by falling ice. Large pieces of debris, up to several tons, have dropped
in populated areas, residential properties, and roads, damaging cars and homes.

Often turbine fires cannot be extinguished because of the height, and are left to burn
themselves out. In the process, they generate toxic fumes and can scatter flaming
debris over a wide area, starting secondary fires
below. Several turbine-ignited fires have burned
hundreds of acres of vegetation each, and one
burned 80,000 hectares (200,000 acres) of
Australian National Park.

Electronic controllers and safety sub-systems
monitor many different aspects of the turbine,
generator, tower, and environment to determine if
the turbine is operating in a safe manner within
prescribed limits. These systems can temporarily shut down the turbine due to high
wind, electrical load imbalance, vibration, and other problems. Reoccurring or
significant problems cause a system lockout and notify an engineer for inspection and
repair. In addition, most systems include multiple passive safety systems that stop
operation even if the electronic controller fails.

Wind power proponent and author Paul Gipe estimated in Wind Energy Comes of
Age that the mortality rate for wind power from 1980–1994 was 0.4 deaths per
terawatt-hour. Paul Gipe's estimate as of end 2000 was 0.15 deaths per TWh, a
decline attributed to greater total cumulative generation.
                                                                                            The Wind Power | 15.02.2009




By comparison, hydroelectric power was found to have a fatality rate of 0.10 per TWh
(883 fatalities for every TW·yr) in the period 1969–1996. This includes the Banqiao
Dam collapse in 1975 that killed thousands. Although the wind power death rate is
higher than some other power sources, the numbers are necessarily based on a
small sample size. The apparent trend is a reduction in fatalities per TWh generated
as more generation is supplied by larger units.

Aesthetics


                                                                                            22
                                                      Historical experience of noisy and visually intrusive wind
                                                      turbines may create resistance to the establishment of land-
                                                      based wind farms. Residents near turbines may complain of
                                                      "shadow flicker" caused by rotating turbine blades. Wind
                                                      towers require aircraft warning lights, which create
                                                      bothersome light pollution. Complaints about these lights
                                                      have caused the FAA to consider allowing fewer lights per
                                                      turbine in certain areas.

                              These effects may be countered by changes in wind farm design.

                              Modern large turbines have low sound levels at ground level. For example, in
                              December 2006, a Texas jury denied a noise pollution suit against FPL Energy, after
                              the company demonstrated that noise readings were not excessive. The highest
                              reading was 44 decibels, which was characterized as about the same level as a 10
                              mile/hour (16 km/hr) wind.

                              Newer wind farms have larger, more widely spaced turbines, and so look less
                              cluttered than old installations.

                              Aesthetic issues are important for onshore and near-shore locations in that the
                              "visible footprint" may be extremely large compared to other sources of industrial
                              power (which may be sited in industrially developed areas). Wind farms may be close
                              to scenic or otherwise undeveloped areas. Constructing offshore wind developments
                              at least 10 km from shore may reduce this concern.
The Wind Power | 15.02.2009




23
Advantages & Disadvantages
     Advantages
  1. The wind is free and with modern technology it can be captured efficiently.
  2. Once the wind turbine is built the energy it produces does not cause green house
     gases or other pollutants.
  3. Although wind turbines can be very tall each takes up only a small plot of land. This
     means that the land below can still be used. This is especially the case in agricultural
     areas as farming can still continue.
  4. Many people find wind farms an interesting feature of the landscape.
  5. Remote areas that are not connected to the electricity power grid can use wind
     turbines to produce their own supply.
  6. Wind turbines have a role to play in both the developed and third world.
  7. Wind turbines are available in a range of sizes which means a vast range of people
     and businesses can use them. Single households to small towns and villages can
     make good use of range of wind turbines available today.

     Disadvantages
  1. The strength of the wind is not constant and it varies from zero to storm force. This
     means that wind turbines do not produce the same amount of electricity all the time.
     There will be times when they produce no electricity at all.
  2. Many people feel that the countryside should be left untouched, without these large
     structures being built. The landscape should left in its natural form for everyone to
     enjoy.
  3. Wind turbines are noisy. Each one can generate the same level of noise as a family
     car travelling at 70 mph.
  4. Many people see large wind turbines as unsightly structures and not pleasant or
     interesting to look at. They disfigure the countryside and are generally ugly.
  5. When wind turbines are being manufactured some pollution is produced. Therefore
     wind power does produce some pollution.
  6. Large wind farms are needed to provide entire communities with enough electricity.
     For example, the largest single turbine available today can only provide enough
     electricity for 475 homes, when running at full capacity. How many would be needed
     for a town of 100 000 people?
                                                                                                The Wind Power | 15.02.2009




                                                                                                24
                              Frequently Asked Questions

                              What is wind energy?

                              Wind energy is, in fact, a converted form of solar energy. The sun's radiation heats different
                              parts of the earth at different rates - most notably during the day and night, but also when
                              different surfaces (for example, water and land,) absorb or reflect at different rates. This in
                              turn causes portions of the atmosphere to warm differently. Hot air rises, reducing the
                              atmospheric pressure at the earth's surface, and cooler air is drawn in to replace it. The
                              result is wind.

                              Air has mass and, when it is in motion, it contains the energy of that motion ("kinetic
                              energy.") Some portion of that energy can be converted into other forms of mechanical force
                              or electricity that we can use to perform work.

                              How does a wind turbine make electricity?

                              The simplest way to think about this is to imagine that a wind turbine works in exactly the
                              opposite way to a fan. Instead of using electricity to make wind, like a fan, turbines use the
                              wind to make electricity.

                              Almost all wind turbines producing electricity consist of rotor blades, which rotate around a
                              horizontal hub. The hub is connected to a gearbox and generator, which are located inside
                              the nacelle. The nacelle is the large part at the top of the tower where all the electrical
                              components are located.

                              Most wind turbines have three blades, which face into the wind. The wind turns the blades
                              around, this spins the shaft, which connects to a generator, and this is where the electricity is
                              made.

                              A generator is a machine that produces electrical energy from mechanical energy, as
                              opposed to an electric motor, which does the opposite.

                              How strong does the wind have to blow for the wind turbines to work?

                              Wind turbines start operating at wind speeds of 4 to 5 m/s and reach maximum power output
                              between 10 to 15 m/s.

                              At very high wind speeds, i.e. gale force winds of 25 m/s, wind turbines shut down.

                              What happens when the wind stops blowing?

                              When the wind stops blowing, electricity continues to be provided from the grid. The
                              European electricity system is mostly made up of large power plants, and the system has to
The Wind Power | 15.02.2009




                              be able to cope if one of these goes out of action.

                              How many turbines does it take to make one megawatt (MW)?

                              Most manufacturers of utility-scale turbines offer machines in the 700-kW to 3.0-MW range.
                              Ten 700-kW units would make a 7-MW wind plant, while 10 3-MW machines would make a
                              30-MW facility. In the future, machines of larger size will be available, although they will
                              probably be installed offshore, where larger transportation and construction equipment can
                              be used. Units up to 5 MW in capacity are now under development.


25
What is a wind power plant?

The most economical application of wind electric turbines is in groups of large machines (660
kW and up) called "wind power plants" or "wind farms."

Wind farms can range in size from a few megawatts to hundreds of megawatts in capacity.
Wind power plants are "modular," which means they consist of small individual modules (the
turbines) and can easily be made larger or smaller as needed. Turbines can be added as
electricity demand grows.

How long do wind turbines last?

A wind turbine typically lasts around 20-25 years. During this time, as with a car, some parts
may need replacing.

How much of the time do wind turbines produce electricity?

A modern wind turbine produces electricity 70-85% of the time, but it generates different
outputs depending on wind speed. Over the course of a year, it will generate about 30% of
the theoretical maximum output. This is known as its load factor.

Could I put a turbine in my garden or on the roof of my house?

More and more householders, communities and small businesses are interested in
generating their own electricity by using small-scale wind turbines, either on their roofs or in
their back gardens. For more information on small scale wind energy download "How to
Manual on Small Scale Wind Energy".

Are wind turbines noisy?

The evolution of wind farm technology over the past decade has rendered mechanical noise
from turbines almost undetectable, with the main sound being the aerodynamic swoosh of
the blades passing the tower. There are strict guidelines on wind turbines and noise
emissions to ensure the protection of residential amenity. It is possible to stand underneath a
turbine and hold a conversation without having to raise your voice. As wind speed rises, the
noise of the wind masks the noise made by wind turbines. For more information, why not visit
a wind farm and experience it for yourself?

Why don't they make turbines that look like old fashioned windmills?

The old-fashioned windmill is viewed with nostalgia, and some people prefer the look of them
to their modern counterparts. Just because wind turbines are modern, it doesn't mean they
won't look just as good over time. A modern wind turbine is simply an improved windmill.
Every aspect of their design has been optimised, making them far more efficient than old-
style windmills at generating electricity. To make them look more old-fashioned would just
                                                                                                   The Wind Power | 15.02.2009




result in more expensive electricity.

What are wind turbines made of?

The towers are mostly tubular and made of steel, generally painted light grey. The blades are
made of glass-fibre reinforced polyester or wood-epoxy. They are light grey since this is the
colour which is most inconspicuous under most lighting conditions. The finish is matt, to
reduce reflected light.



                                                                                                   26
                              Do wind turbines frighten livestock?

                              Wind farming is popular with farmers, because their land can continue to be used for growing
                              crops or grazing livestock. Sheep, cows and horses are not disturbed by wind turbines.

                              I already have utility power, so why should I choose Wind Energy?

                              Photovoltaic systems allow you to lock in your electric rates at today's prices. With fossil fuels
                              likely to become more expensive in the future, purchasing a Wind Energy system today is a
                              smart economic move. In some countries, there is the possibility of having feed in tariffs or
                              incentives to invest. Wind Energy systems also offer greater self-sufficiency, reduce
                              dependence on imported oil, and are far better for the environment than power from
                              conventional power plants.

                              What about electrical interference?

                              Wind turbines, like all electrical equipment, produce electromagnetic radiation, which can
                              interfere with broadcast communications. This interference can be overcome through the
                              installation of deflectors or repeaters.

                              What is a grid connected Wind Energy system?

                              Grid connected means that your system is connected to the utility lines or the quot;grid". A
                              grid connected Wind Energy system is designed to meet all, or a portion of your daily energy
                              needs. This connection enables you to obtain the balance of your electricity from your local
                              utility. It also allows you to send excess solar electricity back to your power company for use
                              later.

                              Isn't Wind Energy electricity expensive?

                              No. The cost of Wind Energy technology has dropped dramatically in last years and, thanks
                              to government incentives or subsidies, a Wind Energy system may be your most cost-
                              effective power solution.

                              Can I use a grid connected Wind Energy system as a back-up source during a utility
                              power outage?

                              A grid connected Wind Energy system can continue to provide electricity to your home during
                              an outage if it has a inverter and batteries.

                              Does my grid connected Wind Energy system have to include batteries?

                              No. Batteries are only essential if you want 'back-up' power in the case of a utility outage.
                              Otherwise, your grid connected Wind Energy system will send any excess generated
                              electricity back to the utility, using the utility grid (rather than batteries) as the storage
The Wind Power | 15.02.2009




                              medium.

                              Can I sell excess wind electricity back to my utility?

                              Electrical utilities in many countries give retail credit to customers who feed excess wind
                              electricity back into the power grid. Known as "net metering," this utility policy is implemented
                              by letting your electric meter spin backwards when you feed excess electricity into the grid. In
                              many countries, the whole amount of wind electricity generated is purchased by the utility
                              company at a rate higher than the tariff applied for consumed electricity. In this case, a
                              dedicated metering exists for wind generation, plus a second metering for domestic

27
consumption. Each applies different tariffs. So in this case, not only the excess electricity is
remunerated, but so too is the total amount of wind production.

What is Net Metering?

If you take the AC output of your Inverter and run it to the mains coming from your utility
power meter, any excess power you generate will feed back into the utility grid and drive your
power meter backwards. This is called Net Metering. Effectively, you will be paid the going
retail price for your electricity up to the amount of energy you use per billing period. Any
excess energy you generate will be credited at a lower rate, or perhaps not at all.

In many countries, the whole amount of wind electricity generated is purchased by the utility
company at a rate higher than the tariff applied for consumed electricity. In this case, a
dedicated metering exists for wind generation, plus a second metering for domestic
consumption. Each applies different tariffs, so in this case, not only the excess electricity is
remunerated, but the total amount of wind production.




                                                                                                   The Wind Power | 15.02.2009




                                                                                                   28
                              References & Sources
                                 Windmillworld.com - http://www.windmillworld.com/windmills/history.htm, 11/4/2008
                                 Wikipedia.org - http://en.wikipedia.org/wiki/Windmill#History 11/4/2008
                                 Telosnet.com - http://www.telosnet.com/wind/early.html 11/4/2008
                                 About.com
                                  http://environment.about.com/od/windpower/Environmental_Issues_Wind_Power.htm, 9/4/2008
                                 Wikipedia - http://en.wikipedia.org/wiki/Wind_power, 11/4/2008
                                 ― Clean Power for Generation ‖ , EWEA
                                 ― The Future of Energy ― , The Economist
                                 http://images.google.com/images?hl=en&q=spain+maps+wind&btnG=Search+Images&gbv=2
                                 http://images.google.com/images?hl=en&q=spain+maps+wind+energy&btnG=Search+Images&gb
                                  v=2
                                 General Department of Electricity Power in Turkey (Elektrik İşleri Etüt İdaresi Genel Müdürlüğü) -
                                  http://www.eie.gov.tr/
                                 The Turkish Wind Power Union - http://www.ruzgarenerjisibirligi.org.tr/bilgibank-uretim-lisans-
                                  alan.htm
                                 http://www.wikipedia.com
                                 http://www.awea.org/faq/wwt_economy.html
                                 http://www.buzzle.com/articles/advantages-disadvantages-wind-energy.html
                                 http://www.climate.org/2002/topics/green/wind.shtml
                                 http://www.expertvillage.com/article/640_wind-energy-advantages.htm
                                 http://www.innovations-report.de/html/berichte/umwelt_naturschutz/bericht-42890.html
                                 http://www.leonardo-energy.org/drupal/faq/557
                                 Free.fr - http://eoliennes.free.fr/eole1_c.html, 11/4/2008
                                 Alwaysdata.net - http://oooxygene.alwaysdata.net/eolienne.html
                                 Windpower.org - http://www.windpower.org/en/tour/wres/euromap.htm
                                 www.wikipedia.de
                                 Vgl. Quaschning Volker; Regenerative Energiesysteme , Hanser 2007, S. 213,214
                                 www.wind-energie.de
                                 Odenwaldwind Gesellschaft für regenerative Energie mbH
                                 Federal association wind industry
                              
The Wind Power | 15.02.2009




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