Wind Energy

1. Wind Energy Modified from : The KidWind Project www.kidwind.org

2. There are lots of exciting career possibilities • Developers • Turbine Technicians • Manufacturing • Sales & Marketing • Utility Engineers • Geophysical Engineers • Concrete/Structural Engineering • Turbine Engineering (ME/EE/Aerospace) • Site/Civil Engineering • Microelectronic/Computer Programming • Business Expertise (Financial) • Legal Expertise • Meteorologists

3. History of Wind Energy, Types of Turbines, and Applications of Wind Energy

4. “Windmills have fascinated us for centuries and will continue to do so. Like campfires or falling water, they’re mesmerizing; indeed, entrancing.” Paul Gipe, Wind Power for Home, Farm, & Business

5. Basic Nomenclature • Wind Machine • Kinetic device used to capture the wind and put it to work • Windmill • Wind machine that generates mechanical motion (i.e.. water pumping, grain grinding, etc.) • Wind Turbine • A device that produces electricity from the kinetic energy of wind

6. Wind Energy has been Popular for a long time The first settlers arrived under the power of wind. Wind helped fuel our country’s early economy.

7. Early “WINDMILL” in Afghanistan (900AD)

8. Dutch Style Windmills used for 100s of years across the World

9. Water Pumping Windmills helped settle the Canadian West

10. Early Electric Wind Turbines helped Electrify Remote Farms in the early 1900’s

11. Birth of the Modern Wind Turbine California Wind Turbines 1980’s Smith-Putnam 1.25 MW Turbine Vermont, 1940's

12. Wind is Fastest Growing Energy Source US Installed Wind Capacity

13. Drivers for Wind Power • Rising Fuel Price and Uncertainty • Declining Wind Costs • Federal and State Policies & Incentives • Local Economic Development • Environmental Stewardship • Energy Security • Consumer Demand • Climate Change • Oil Costs

14. Need to Change Perceptions…

15. Types of Wind Turbines Today • Medium • Village Power • Hybrid Systems • Distributed Power • $80,000-$500,000 • 20-150 ft. diameter • 10-250 kW • Small • Homes & Farms • Remote Applications • $5,000-$50,000+ • 2-20 ft. diameter • 10 kW • Large (250 kW – 5 MW) • Central Station Wind Farms • Distributed Power • $750,000 - $3,000,000 (per turbine) • 150 – 300 ft. diameter

17. Micro <1.25 m (4 ft) rotor diameter Mini / Cabin-size 1-3 m (3-10 ft) rotor diameter Household 4-10 m (13-33 ft) rotor diameter Medium 10-60 m (33-200 ft) rotor diameter Small & Medium Turbines

18. US Small Wind Manufacturers • Bergey, Oklahoma • Southwest, Arizona Abundant Renewable Energy (ARE), Oregon

19. Medium & Large Wind Turbines • Hub height : • 160’ - 260’ • Blade tip height: • 240’ - 390’

20. US Large Wind Manufactures • General Electric • Clipper

21. Workers Blade 112’ long Nacelle 56 tons Tower 3 sections Wind Turbine Perspective

22. 231 ft. 211 ft. Wide Sweep

24. Turbine Technology

25. Orientation Turbines can be categorized into two overarching classes based on the orientation of the rotor Vertical AxisHorizontal Axis

26. Lift vs. Drag VAWTs Lift Device “Darrieus” • Low solidity, aerofoil blades • More efficient than drag device Drag Device “Savonius” • High solidity, cup shapes are pushed by the wind • At best can capture only 15% of wind energy

27. VAWT’s have not been commercially successful, yet… Every few years a new company comes along promising a revolutionary breakthrough in wind turbine design that is low cost, outperforms anything else on the market, and overcomes all of the previous problems with VAWT’s. They can also usually be installed on a roof or in a city where wind is poor. WindStor Mag-Wind WindTree Wind Wandler

28. Horizontal Axis Wind Turbines • Rotors are usually Up-wind of tower • Some machines have down-wind rotors, but only commercially available ones are small turbines

30. Inside a Wind Turbine

31. Airfoil Nomenclaturewind turbines use the same aerodynamic principals as aircraft

32. Active & Passive Yaw • 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

33. Pitch Control vs. Stall Control • Pitch Control • Blades rotate out of the wind when wind speed becomes too great • Stall Control • Blades are at a fixed pitch that starts to stall when wind speed is too great • Pitch can be adjusted for particular location’s wind regime • Active Stall Control • Many larger turbines today have active pitch control that turns the blades towards stall when wind speeds are too great

34. “The rotor is the single most critical element of any wind turbine… How a wind turbine controls the forces acting on the rotor, particularly in high winds, is of the utmost importance to the long-term, reliable function of any wind turbine.” Paul Gipe Micro Turbines May not have any controls Blade flutter Small Turbines Furling (upwind) – rotor moves to reduce frontal area facing wind Coning (downwind) – rotor blades come to a sharper cone Passive pitch governors – blades pitch out of wind Medium Turbines Aerodynamic Stall Mechanical Brakes Aerodynamic Brakes Rotor Controls

35. What is Wind Power Used For?

36. Wind Turbine Applications • Generating electricity at Remote Sites • Producing electricity in parallel with utility • Water Pumping

37. Electricity for Remote Sites • North American Farms in 30’s & 40’s • Backcountry homes/cabins • Research Stations • Telecommunications • Boats & RV’s • Nomadic people • Cathodic protection • …

38. Hybrid Systems & Rural Electrification

39. Merchant Electricity Generation

40. Net Metering

41. Wind Farms

42. Offshore Wind

43. How Wind Works Wind energy is created by uneven heating of the earth’s surface.

44. Where is the Wind?

47. Wind Varies Seasonally

48. Wind Varies Daily • Wind varies daily not only because of weather but because of convective heating • Winds typically strongest in mid-late afternoon • Convective heating is less of an influence in winter, when storms dominate wind patterns

49. Power in the Wind

50. Calculation of Wind Power • Power in the wind • = ½  A V3 • 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).