Wind Energy
Where is Wind Energy Found?
~ Places where there is constant wind
~ Some places are better for wind
turbines
~ How is the wind extracted?
Wind Turbines
• Wind turbines capture the wind’s energy with 2 or 3
propeller-like which are mounted on a rotor, to generate
electricity.
• Wind blows and a pocket pressure air forms on the
downward side of the blade.
• Low-pressure pulls the blade toward it, causes the rotor
to run.
• A lift and drag occur making the generator to work to
make electricity.
How Does Wind Energy Work?
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Kinetic energy in the wind changes to electronic energy to be used.
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The wind blows on the blades and makes them turn.
The blades turns a shaft inside the nacelle (the box at the top of
the turbine)
The shaft goes into a gearbox which increases the rotation speed
enough for...
The generator, which uses magnetic fields to convert the
rotational energy into electrical energy. These are similar to those
found in normal power stations.
The power output goes to a transformer, which converts the
electricity coming out of the generator at around 700 Volts (V) to
the right voltage for distribution system, typically 33,000 V.
The national grid transmits the power around the country.
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Parts of a Wind Turbine
Where is the best place to have a wind
farm?
• California has many windy areas
• It’s normally windier in summer months when
wind comes from cooler areas inland. The ocean
replaces the hot raising air in California’s warm
deserts & central valleys.
• 3 windiest places:
– Altamont Pass (east of San Francisco)
– San Gorgonio (near Palm Springs)
– Tehachapi (south of Bakersfield)
~ These 3 places = electricity to supply a city the size of
San Francisco
For a wind turbine to work…
• Need 12-15 miles/hour winds
• Produce about 50-300 kilowatts of
electricity each (kilowatts = 1,000 watts)
• 100 watt light bulb = 1,000 watts
• 300 kilowatt wind turbine = 3,000 light
bulbs that use 100 watts!
• As of 1999, there were 11,368 wind
turbines in California
Offshore Wind Turbines
• East coast sparked interest for turbines to
harvest offshore winds
• Offshore = more expensive
• Northeast coast offshore development is
attractive alternative
• Europeans have some experience, but
w/shallow and sheltered water cites
• Designed w/confidence in offshore winds
(higher energy and lower turbulence)
Wind as a replacement
Fossil Fuels
• Coal
• Oil
Nuclear Power
Advantages
• Produce No pollution
• Entirely renewable
• Infinite Resource
Ready to Become a Significant
Power Source
coal
coal
petroleum
petroleum
natural gas
natural gas
nuclear
nuclear
hydro
hydro
other renewables
other renewables
wind
wind
Wind currently produces less than
1% of the nation’s power.
Source: Energy Information Agency
Wind could
generate
6% of
nation’s
electricity
by 2020.
Technologies Improving
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Larger turbines
Specialized blade design
Power electronics
Computer modeling produces more
efficient design
• Manufacturing improvements
U.S. Department of Energy Advanced Small Wind Turbine
Program
• Advanced airfoils
• "Super-magnet"
generators
• Low cost manufacturing
• Smart power electronics
• Very tall towers
• "Stealth" low noise
& visual impact
Wind Energy Technologies
• Horizontal Axis Turbines (HAWT)
• Vertical Axis Turbines (VAWT)
• Windmills
Horizontal Axis Turbines
• Propeller Type
• Most Common
• Utility Scale
Vertical Axis Turbines
• Lift Base Turbine
Vertical Base Turbines
• Drag Base Turbine
Windmills
Wind
*Wind energy has minor impacts on our environment.
*Wind energy plants produce no air pollutants or greenhouse gases.
Impacts that are most commonly
addressed.
• Wildlife and wildlife habitat, including avian
impacts.
• Visual environment
• Social and economic considerations
Wind Impacts
• Positive impacts
• Negative impacts
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*Wind turbines are relatively quiet. (they
are compared to the sound level of a
refrigerator)
Now they coexist safely with many land
uses, including schools, highways,
hiking trails and farms.
*In the Renewable Energy Policy project
studied 25,000 property transactions and
did not find evidence of wind power
reducing property values.
*The FAA requires turbines to be lit and
to be at least 200 ft. tall.
***Air quality in the U.S. has improved
since the Clean Air Act of 1970 because
of these wind turbines.
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*Have caused bird and bat
collisions…mainly in the 80’s and
the 90’s, so far only in the U.S.
*Negative environmental impacts of
wind power come from the change
in habitat that results from the
clearing of the land.
***The fact that our growing energy
still harms us and the environment.
When using the wind turbines we
have to use electricity from fossil
fuels, which emits CO2,SO2,NOx, and
much more.
Would you spend your tax dollars
to fund this source?
• Yes, we most definitely would…
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Wind power is a clean, renewable source of energy which produces no greenhouse
gas emissions or waste products.
A modern wind turbine is designed to operate for more than 20 years and at the end
of its working life, the area can be restored at low financial and environmental costs.
Wind power provides at least 10% of our nation’s electricity needs.
Wind is an abundant resource.
Wind power is currently the most cost effective renewable energy technology.
The cost of generating electricity from wind has fallen dramatically over the past few
years. (wind is a free and widely available fuel source)
On average 80% of people support wind energy.
Wind energy is technology with no associated emissions, harmful pollutants, or waste
products.
Almost all wind turbines have an undetectable sound.
Bibliography
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"Alternative Energy." Palmdale Water District. 23 Oct. 2005
<http://www.palmdalewater.org/OC/AE/wind.html>.
"Wind Energy." 19 July 2005. American Wind Energy Association. 23 Oct.
2005 <http://www.awea.org/#Wind%20energy>.
"Wind Energy." Energy Story. 26 Oct. 2005
<http://www.energyquest.ca.gov/story/chapter16.html>.
"Wind Energy; How Does Wind Energy Work?" Wind Energy. 13 Oct. 2005.
The British Wind Energy Association. 24 Oct. 2005
<http://www.bwea.com/energy/how.html>.
"Wind Energy Topics." U.S. Department of Energy. 23 Oct. 2005
<http://www.eere.energy.gov/RE/wind.html>.
"Wind Power: Impacts and Issues." Ceere. 13 Oct. 2005. Renewable
Energy Research Laboratory, University of Massachusetts at Amherst. 26
Oct. 2005
<http://www.ceere.org/rerl/about_wind/RERL_Fact_Sheet_3_Impacts&Issue
s.pdf>.