It Blows You Away

1. It Blows You Away

2. "Coal, gas and oil will not be the three kings of the energy world for ever. It is no longer folly to look up to the sun and wind, down into the sea's waves"

3. Introduction

4. Energy is a major input for overall socio-economic development of any society • The prices of the fossil fuels steeply increasing • So renewables are expected to play a key role • Wind energy is the fastest growing renewable • Wind turbines are up to the task of producing serious amounts of electricity

5. Principles

6. Uneven heating of earth’s surface and rotation

7. Beaufort Scale

9. Velocity with Height

10. Power vs. Velocity

11. Lift and drag forces

12. Solidity and Tip speed ratio

13. Performance co-efficient and Betz criterion

14. Potential

15. Huge potential exists • Available potential can contribute five times the world energy demand • 0.4% contribution to total energy

16. Wind is currently the world’s fastest growing energy source

18. Growth of Wind Energy MW Installed Year

20. Wind Energy generating capacity by country, 1980-2003

21. Installed Capacity (MW) in 2005

22. Available potential in India

23. Wind Power Density of India

24. All India Fuel wise Installed Capacity, 2004

26. State wise potential in India, 2005

27. Technology

28. Turbine Evolution • Used for • Pumping water • Grinding grain • Mainly used for • Generating Electricity

29. Types of turbines VAWT • Drag is the main force • Nacelle is placed at the bottom • Yaw mechanism is not required • Lower starting torque • Difficulty in mounting the turbine • Unwanted fluctuations in the power output

30. HAWT • Lift is the main force • Much lower cyclic stresses • 95% of the existing turbines are HAWTs • Nacelle is placed at the top of the tower • Yaw mechanism is required

31. Two types of HAWT DOWNWIND TURBINE UPWIND TURBINE

32. Counter Rotating HAWT • Increase the rotation speed • Rear one is smaller and stalls at high wind speeds • Operates for wider range of wind speeds

33. Offshore turbines • More wind speeds • Less noise pollution • Less visual impact • Difficult to install and maintain • Energy losses due long distance transport

34. A Typical HAWT

35. Turbine design and construction • Blades • Material used • Typical length • Tower height • Heights twice the blade length are found economical

36. Number of blades • Three blade HAWT are most efficient • Two blade turbines don’t require a hub • As the number increases; noise, wear and cost increase and efficiency decreases • Multiple blade turbines are generally used for water pumping purposes

37. Rotational control • Maintenance • Noise reduction • Centripetal force reduction • Mechanisms • Stalling • Furling

38. Yaw Mechanism • To turn the turbine against the wind • Yaw error and fatigue loads • Uses electric motors and gear boxes • Wind turbine safety • Sensors – controlling vibrations • Over speed protection • Aero dynamic braking • Mechanical braking

39. Improvements • Concentrators

40. Future Wind Turbines Wind Amplified Rotor Platform

41. Disc type wind turbine • Much more efficient than HAWT • Requires less height • Low noise • Works in any wind direction

42. Economics

43. Determining Factors • Wind Speed • Turbine design and construction • Rated capacity of the turbine • Exact Location • Improvements in turbine design • Capital

44. Wind Speed Matters Assuming the same size project, the better the wind resource, the lower the cost.

45. Size Matters Assuming the same wind speed of 8.08 m/s, a large wind farm is more economical

46. Overall cost distribution

47. Break down of capital cost

48. Energy Cost Trend 1979: 40 cents/kWh 2000: 4 - 6 cents/kWh • Increased Turbine Size • R&D Advances • Manufacturing Improvements 2004: 3 – 4.5 cents/kWh

49. Typical cost statistics • Size: 51 MW • Wind Speed: 13-18 miles/hour • Capital cost: $ 65 million ($1300/MW) • Annual production: 150 million kW-hr • Electricity costs: 3.6-4.5 cents • Payback period: 20 years

50. Economic Advantages