Wind turbines convert the kinetic energy of wind into mechanical energy using rotor blades, a shaft, and a generator. As wind passes through rotor blades, lift and drag forces cause them to spin, transferring mechanical energy to the generator via the shaft. Within the generator, this mechanical energy is converted into electrical energy via electromagnetic induction. Additional gearing is often used to increase the rotor shaft's RPM to a rate suitable for efficient electricity production. Horizontal axis wind turbines also use yaw systems to face rotor blades into the wind for maximum energy capture as wind direction changes. Braking mechanisms limit blade speed during high winds to prevent equipment damage.

1. HOW WIND TURBINES GENERATE ELECTRICITY

2. First, let’s answer a very important question.

3. What are Wind Turbines?

4. What are Wind Turbines? Wind turbines are devices that convert the wind’s kinetic energy into mechanical energy.

5. What are Wind Turbines? If it further converts the mechanical energy to electricity, then we call it a wind generator.

6. WARNING!

7. WARNING! For convenience, whenever you see the word “wind turbine” after this slide, it will refer specifically to a wind generator.

8. Wind turbines have a variety of shapes and sizes…

10. But they’re all composed of the same 3 basic parts.

11. Basic Parts

12. Basic Parts A. Rotor Blades

13. Basic Parts A. Rotor Blades

14. Basic Parts B. Shaft A. Rotor Blades

15. Basic Parts B. Shaft A. Rotor Blades

16. Basic Parts B. Shaft A. Rotor Blades C. Generator

17. Basic Parts B. Shaft A. Rotor Blades C. Generator

18. Basic Parts A. Rotor Blades The rotor blades are the “wind catchers” of a wind turbine.

19. Basic Parts A. Rotor Blades They’re long projections that have aerodynamic designs.

20. Basic Parts A. Rotor Blades When wind passes, it forces these rotor blades to turn.

21. Basic Parts B. Shaft The shaft is a rod that connects the rotor blades to the generator.

22. Basic Parts B. Shaft Its main purpose is to transfer the rotational mechanical energy of the rotor blades to the generator.

23. 3 Basic Parts C. Generator Finally, the generator is a device designed to convertmechanical energy into electrical energy.

24. 3 Basic Parts C. Generator It uses the principle of electromagnetic induction.

25. Now that you know its basic parts, let’s understand how wind turbines generate electricity.

26. Basic Processes

27. Basic Processes A. Capturing Wind Energy

28. Basic Processes A. Capturing Wind Energy B. Converting to Electricity

29. Basic Processes A. Capturing Wind Energy

30. Basic Processes A. Capturing Wind Energy Wind energy is captured using the wind turbine’s rotor blades.

31. Basic Processes A. Capturing Wind Energy Wind energy is captured using the wind turbine’s rotor blades.

32. Basic Processes A. Capturing Wind Energy When wind passes through the blades, two aerodynamic forces are at work.

33. Basic Processes A. Capturing Wind Energy Rotor Blade

34. Basic Processes A. Capturing Wind Energy LIFT Rotor Blade

35. Basic Processes A. Capturing Wind Energy LIFT Rotor Blade DRAG

36. Basic Processes A. Capturing Wind Energy These two forces cause the rotor blades to turn, depending on how much force the wind exerts on them.

37. Basic Processes A. Capturing Wind Energy The process converts the wind’s kinetic energy to mechanical energy (turning of rotor blades)

38. After this, it’s time to convert the mechanical energy into electricity.

39. Basic Processes B. Converting to Electricity The turning of the rotor blades would simultaneously cause the shaft to turn, which is connected to a generator.

40. Basic Processes B. Converting to Electricity When the rotor blades turn,

41. Basic Processes B. Converting to Electricity When the rotor blades turn,

42. Basic Processes B. Converting to Electricity the shaft also turns.

43. Basic Processes B. Converting to Electricity the shaft also turns.

44. Basic Processes B. Converting to Electricity Which makes the generator produce electricity!

45. Basic Processes B. Converting to Electricity Which makes the generator produce electricity!

46. Basic Processes B. Converting to Electricity In this process, the rotational mechanical energy of the shaft is converted to electricity by the generator.

47. Thanks to technology, modern wind turbines

48. have a host of other features

49. that help in solving some other problems.

50. Other Processes Involved

51. Other Processes Involved Increasing RPM

52. Other Processes Involved Increasing RPM You might notice that large wind turbines turnslowly.

53. Other Processes Involved Increasing RPM On average, their rotor blades rotate at a speed of 20 rpm (rotations per minute).

54. Other Processes Involved Increasing RPM 20 rpm is tooslow to power up a generator!

55. Other Processes Involved Increasing RPM Large wind turbines use a gearbox to increase the rpm from 20 rpm to as much as 2000 rpm!

56. Other Processes Involved Increasing RPM To understand the process, let’s examine these two gears:

57. Other Processes Involved Increasing RPM Gear A Gear B

58. Other Processes Involved Increasing RPM Gear A Gear A has 9 gear teeth Gear B

59. Other Processes Involved Increasing RPM Gear A while Gear B only has 6. Gear A has 9 gear teeth Gear B

60. Other Processes Involved Increasing RPM Gear A while Gear B only has 6. This would mean that 1 revolution of Gear A would be equal to 1.5 (9÷6) revolutions for Gear B. Gear A has 9 gear teeth Gear B

61. Other Processes Involved Increasing RPM Gear A while Gear B only has 6. So if Gear A revolves at a rate of 20 rpm, Gear B would revolve at a faster rate of 30 (20×1.5) rpm. Gear A has 9 gear teeth Gear B

62. Other Processes Involved Increasing RPM In large wind turbines, they use a variety of gears (hence the name, gearbox) to multiply the rpm of the shaft.

63. Other Processes Involved Yaw Adjustment (HAWT only) HAWTs (horizontal-axis wind turbines) should be directed the same direction as the wind to maximize the energy collected.

64. Other Processes Involved Yaw Adjustment (HAWT only) Wind direction isn’t constant though,

65. Other Processes Involved Yaw Adjustment (HAWT only) So modern HAWTs use a yaw-adjustment system

66. Other Processes Involved Yaw Adjustment (HAWT only) To position the rotor blades in the correct direction.

67. Other Processes Involved Yaw Adjustment (HAWT only) The system usually consists of a sensor to monitor wind direction

68. Other Processes Involved Yaw Adjustment (HAWT only) and a motor to adjust turbine direction.

69. Other Processes Involved Braking Mechanism Finally, there are places where wind speeds can reach extremely high levels.

70. Other Processes Involved Braking Mechanism Overspeeding of the rotor blades can cause malfunctions on the wind turbine’s system.

71. Other Processes Involved Braking Mechanism This is why a braking mechanism should exist to limit the maximum speed of the rotor blades.

72. Image Credits All other illustrations are properties of:

73. To learn more about the wind turbine community, visit WindTurbines.Net.

74. END