Wind Energyfor Students

The Kidwind ProjectThe Kidwind Projectwww.kidwind.orgwww.kidwind.org

Copyright 2008Copyright 2008

Electricity!

• How much would it cost to run this 100 Watt bulb for a full day (24 hrs)?

• 100 Watts x 24 hours = 2400 Watt Hours (2400 Watt Hours = 2.4 Kilowatt Hours)

• 2.4 kWh x $0.08/kWh = $0.19

• What about this 25 Watt CFL light bulb, which produces the same amount of light?

• 25 Watts x 24 hours = 600 Watt Hours (600 Watt Hours = 0.6 Kilowatt Hours)

• 0.6 kWh x $0.08/kWh = $0.05

More efficient light bulbs are great, but what is the BEST way to conserve electricity and reduce our consumption of fossil fuels???

TURN IT OFF!!!Be conscious of your energy choices!

Where do we get our electricity?Where do we get our electricity?

What is a Fossil Fuel???

What is “Renewable Energy?”

Types of Electricity Generating Windmills

Small (10 kW)•Homes•Farms•Remote Applications (e.g. water

pumping, telecom sites, icemaking)

Large (250 kW - 2+MW)

•Central Station Wind Farms

•Distributed Power

Intermediate (10-250 kW)•Village Power•Hybrid Systems•Distributed

Power

Parts of a Wind Turbine

Wind Turbine Perspective

Nacelle56 tons

Tower3 sections

Workers Blade112’ long

150 m2

250 m2

800 m2

1,800 m2

3,700 m2

19801985

1990

19952000

A= 12,000 m2

2005 How big will wind turbines be?

2010

Slide courtesy NREL

Large Wind Turbines

• 450’ base to blade• Each blade 112’• Span greater than 747• 163+ tons total• Foundation 20+ feet deep• Rated at 1.5 – 5 megawatt• Supply at least 350 homes

Yawing – Facing the WindYawing – Facing the Wind• Active Yaw (all medium &

large turbines produced today, & some small turbines from Europe)– Anemometer on nacelle tells

controller which way to point rotor into the wind

– Yaw drive turns gears to point rotor into wind

• Passive Yaw (Most small turbines)– Wind forces alone direct rotor

• Tail vanes• Downwind turbines

Why do windmills need to be high in the sky??

Importance of Wind Speed• No other factor is more

important to the amount of power available in the wind than the speed of the wind

• Power is a cubic function of wind speed– V X V X V

• 20% increase in wind speed means 73% more power

• Doubling wind speed means 8 times more power

Calculation of Wind Power

•Power in the wind Effect of air density,

– Effect of swept area, A– Effect of wind speed, V

R

Swept Area: A = πR2 Area of the circle swept by the rotor (m2).

Power in the Wind = ½ρAV3

Carnage!

Jobs in the Wind Industry

Construction

Operations/Maintenance

Engineering/Design

Public Relations/Organizing Support

Environmental Impact Assessment

Questions???