1. Alternative Energy Sources

2. Wind Turbines

3. Wind: A General Description Wind energy- is a renewable resource that is used to create electrical energy. Wind- is a natural force that results from the uneven heating of the earth from the sun.

4. What are wind turbines made of? All wind turbines, are comprised of the following components: The Rotor is used to convert the kinetic energy of wind into rotational force used to turn a generator The Gearbox is used to change the speed and torque of the Rotor The Generator (makes electricity) Tower

5. How is the energy in the wind captured? Wind turbines, are like aircraft propeller blades that turn in the moving air. They power an electric generator, which supplies electrical energy. Modern wind turbines fall into two basic groups Horizontal-axis variety, like the traditional farm windmills used for pumping water Vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor.

6. How is the energy in the wind captured? Modern wind turbines fall into two basic groups Horizontal-axis variety, like the traditional farm windmills used for pumping water Vertical-axis design, like the eggbeater-style Darrieus model, named after its French inventor.

7. Wind: Current Technology Use of wind the fastest growing renewable, unlimited energy resource. Wind maps determine suitable locations for “Wind farms” “Wind farms” currently provide ________ MW of electricity.

8. Wind Technology: “Wind Map”

10. Jiminy Peak, Hancock Mass.- The Zephyr Turbine www.jiminypeak.com

12. The purpose of a wind turbine rotor is to convert the kinetic energy of wind into rotational force used to turn a generator.

13. Blade Design Tradeoffs Blade size Bigger = more surface available to catch wind Bigger blades weigh more

14. Blade Design Tradeoffs Shape & number All blades must produce lift to work. To do this an airfoil must be created, this is done in many ways depending on size, price and material used.

15. Airfoil Airfoil A surface designed to produce lift from the movement of air over it.

16. Aerodynamics Aerodynamics the study of the flow of air around and through an object.

17. Blade Orientation Leading edge of each blade needs to point towards the next blade’s trailing edge. In order to sustain motion. HUB Wind Turbine Blade Leading Edge Trailing Edge

18. Blade Pitch The Blade Pitch is the angle of the rotor blade in relation to the rotor. When you have the correct pitch your rotor will spin When you have too much pitch the rotor will stall (will not spin)