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Wind energy harvesting basics,                    resource assessment and                 application for off grid systems...
OutlineThursday, November 10, 2011
Outline              •      part II (2 hours)Thursday, November 10, 2011
Outline              •      part II (2 hours)                   •      Example projectThursday, November 10, 2011
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Outline              •      part II (2 hours)                   •      Example project                         •      Esti...
Resource: ITDG_2001_bookletwind.pdf                                Example projectThursday, November 10, 2011
Small wind development by technology                                 transferThursday, November 10, 2011
Small wind development by technology                                         transfer                  • ITDG (now called ...
Small wind development by technology                                         transfer                  • ITDG (now called ...
Small wind development by technology                                         transfer                  • ITDG (now called ...
Small wind development by technology                                         transfer                  • ITDG (now called ...
Small wind development by technology                                         transfer                  • ITDG (now called ...
Small wind development by technology                                         transfer                  • ITDG (now called ...
Small wind development by technology                                         transfer                  • ITDG (now called ...
Small wind development by technology                                         transfer                  • ITDG (now called ...
Small wind development by technology                                         transfer                  • ITDG (now called ...
Current situation           •      12V Car batteries are used for                  radios and TVs           •      60Ah or...
Estimating the wind           •      Anecdotal evidence           •      The local vegetation           •      The Beaufor...
Beaufort scaleThursday, November 10, 2011
Siting the        wind turbine           •      The highest                  point           •      Open to               ...
Siting the                  Highest                                      point        wind turbine           •      The hi...
Siting the                                       Highest                                     Too far from loads    point  ...
Choosing AC vs. DC           •      For a wind turbine installed far from                  the load normally the battery v...
Choosing AC vs. DC           •      But cost of DC-AC inverter                  can be substantial           •      Altern...
Conservative estimate of monthly                               electricity production      •      Assuming efficiency is 15...
Estimating the loads           •      What the wind shouldn’t power:                 •      Electric heaters              ...
Single householdThursday, November 10, 2011
Single household                                           Rule of thumb -                                       battery c...
Breaking down the load for a typical dayThursday, November 10, 2011
3 households sharing a turbineThursday, November 10, 2011
3 households sharing a turbineThursday, November 10, 2011
3 households sharing a turbineThursday, November 10, 2011
3 households sharing a turbineThursday, November 10, 2011
Sizing the turbine            In an ideal world -           1. Identify wind resource           2. Identify electricity ne...
Sizing the turbine for our two examplesThursday, November 10, 2011
Sizing the turbine for our two examples                              Enough spare energyThursday, November 10, 2011
Sizing the turbine for our two examples                                Not enough energyThursday, November 10, 2011
Sizing the battery      • The battery is charged and discharged            over a period of hours or days.      • This is ...
Sizing the batteryThursday, November 10, 2011
Sizing the batteryThursday, November 10, 2011
Sizing the batteryThursday, November 10, 2011
Sizing the Battery           •      Calculate Ep, the daily consumption in                  Wh                  (for examp...
Sizing the Battery                          Calculate C, battery capacity:           •      Calculate Ep, the daily consum...
Cost of wind turbine - 2 meter                                diameter, 100 watt ratedThursday, November 10, 2011
Economics                   •          Financing ownership by battery charging services                   •          Curre...
EconomicsThursday, November 10, 2011
Final system componentsThursday, November 10, 2011
Final system components            Sizing according to local            need and wind resourceThursday, November 10, 2011
Final system componentsThursday, November 10, 2011
Final system components                              Sizing according to wind                               variability an...
Final system componentsThursday, November 10, 2011
Final system components                                  For an AC system -                                according to ma...
Final system componentsThursday, November 10, 2011
Small wind turbine marketThursday, November 10, 2011
WT brochure                                                                                                               ...
Small wind turbine marketThursday, November 10, 2011
Source -  American magazine.   2 mph = 1 m/s               Small wind turbine marketThursday, November 10, 2011
Small wind turbine marketThursday, November 10, 2011
Most important       parameter               Small wind turbine marketThursday, November 10, 2011
Small wind turbine marketThursday, November 10, 2011
Case studiesThursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
small wind:                                      0.2$-1.15$ / kWh                                solar PV:                ...
African Wind PowerThursday, November 10, 2011
•       Example of                 technology                 transfer                          African Wind PowerThursday...
•       Example of                 technology                 transfer         •       Turbines now                 instal...
AWP - Zimbabwe - Masampa Village Lake Kariba                   •          AWP3.6 - 48V 13.5M tilt up tower, 275Ahr 48V Bat...
AWP - Zimbabwe - Masampa Village Lake Kariba   •      AWP3.6 - 48V 13.5M tilt up tower, 275Ahr 48V Battery bank, 3KW sine ...
WindAid - PeruThursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Thursday, November 10, 2011
Comet-METhursday, November 10, 2011
Comet-METhursday, November 10, 2011
Comet-METhursday, November 10, 2011
Comet-METhursday, November 10, 2011
Comet-METhursday, November 10, 2011
Comet-ME      •       The systems are designed for producing 2-3 kWh/              day for a large beduin family.      •  ...
ResourcesThursday, November 10, 2011
ResourcesThursday, November 10, 2011
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Small wind power for rural locations - part 2

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Transcript of "Small wind power for rural locations - part 2"

  1. 1. Wind energy harvesting basics, resource assessment and application for off grid systems. part 2 Hanan Einav-Levy M.Sc.Thursday, November 10, 2011
  2. 2. OutlineThursday, November 10, 2011
  3. 3. Outline • part II (2 hours)Thursday, November 10, 2011
  4. 4. Outline • part II (2 hours) • Example projectThursday, November 10, 2011
  5. 5. Outline • part II (2 hours) • Example project • Estimating the wind resource (5)Thursday, November 10, 2011
  6. 6. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10)Thursday, November 10, 2011
  7. 7. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5)Thursday, November 10, 2011
  8. 8. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5)Thursday, November 10, 2011
  9. 9. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10)Thursday, November 10, 2011
  10. 10. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10) • Sizing the inverter (5)Thursday, November 10, 2011
  11. 11. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10) • Sizing the inverter (5) • Economics (10)Thursday, November 10, 2011
  12. 12. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10) • Sizing the inverter (5) • Economics (10) • Small wind turbine product comparison (10)Thursday, November 10, 2011
  13. 13. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10) • Sizing the inverter (5) • Economics (10) • Small wind turbine product comparison (10) • Case studiesThursday, November 10, 2011
  14. 14. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10) • Sizing the inverter (5) • Economics (10) • Small wind turbine product comparison (10) • Case studies • Practical action - Peru (10)Thursday, November 10, 2011
  15. 15. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10) • Sizing the inverter (5) • Economics (10) • Small wind turbine product comparison (10) • Case studies • Practical action - Peru (10) • AWP - Zimbabwe (10)Thursday, November 10, 2011
  16. 16. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10) • Sizing the inverter (5) • Economics (10) • Small wind turbine product comparison (10) • Case studies • Practical action - Peru (10) • AWP - Zimbabwe (10) • WindAid - Peru (10)Thursday, November 10, 2011
  17. 17. Outline • part II (2 hours) • Example project • Estimating the wind resource (5) • Estimating the needs (10) • Sizing the turbine (5) • AC or DC (5) • Sizing the battery bank (10) • Sizing the inverter (5) • Economics (10) • Small wind turbine product comparison (10) • Case studies • Practical action - Peru (10) • AWP - Zimbabwe (10) • WindAid - Peru (10) • CometME - Israel / Palestinian authority (10)Thursday, November 10, 2011
  18. 18. Resource: ITDG_2001_bookletwind.pdf Example projectThursday, November 10, 2011
  19. 19. Small wind development by technology transferThursday, November 10, 2011
  20. 20. Small wind development by technology transfer • ITDG (now called Practical Action)Thursday, November 10, 2011
  21. 21. Small wind development by technology transfer • ITDG (now called Practical Action) • One method to develop wind turbines for rural communities - there are others.Thursday, November 10, 2011
  22. 22. Small wind development by technology transfer • ITDG (now called Practical Action) • One method to develop wind turbines for rural communities - there are others. • We will use this to study the design of the systemThursday, November 10, 2011
  23. 23. Small wind development by technology transfer • ITDG (now called Practical Action) • One method to develop wind turbines for rural communities - there are others. • We will use this to study the design of the system • Estimating the wind resourceThursday, November 10, 2011
  24. 24. Small wind development by technology transfer • ITDG (now called Practical Action) • One method to develop wind turbines for rural communities - there are others. • We will use this to study the design of the system • Estimating the wind resource • Estimating the needsThursday, November 10, 2011
  25. 25. Small wind development by technology transfer • ITDG (now called Practical Action) • One method to develop wind turbines for rural communities - there are others. • We will use this to study the design of the system • Estimating the wind resource • Estimating the needs • Sizing the turbineThursday, November 10, 2011
  26. 26. Small wind development by technology transfer • ITDG (now called Practical Action) • One method to develop wind turbines for rural communities - there are others. • We will use this to study the design of the system • Estimating the wind resource • Estimating the needs • Sizing the turbine • AC or DCThursday, November 10, 2011
  27. 27. Small wind development by technology transfer • ITDG (now called Practical Action) • One method to develop wind turbines for rural communities - there are others. • We will use this to study the design of the system • Estimating the wind resource • Estimating the needs • Sizing the turbine • AC or DC • Sizing the battery bankThursday, November 10, 2011
  28. 28. Small wind development by technology transfer • ITDG (now called Practical Action) • One method to develop wind turbines for rural communities - there are others. • We will use this to study the design of the system • Estimating the wind resource • Estimating the needs • Sizing the turbine • AC or DC • Sizing the battery bank • Sizing the inverterThursday, November 10, 2011
  29. 29. Current situation • 12V Car batteries are used for radios and TVs • 60Ah or 90Ah battery typically used • A large market for existing battery users (300,000 households) • Monthly battery cost 6.5$ (5$ battery replacement, 1$ travel, 0.5$ charging)Thursday, November 10, 2011
  30. 30. Estimating the wind • Anecdotal evidence • The local vegetation • The Beaufort scale • Wind map • Installing an anemometer+data logging equipment - 200-1000$ • Installing a wind turbine with data logging equipment with the same fundsThursday, November 10, 2011
  31. 31. Beaufort scaleThursday, November 10, 2011
  32. 32. Siting the wind turbine • The highest point • Open to prevailing winds • Not too far from load • On a tall tower!Thursday, November 10, 2011
  33. 33. Siting the Highest point wind turbine • The highest point • Open to prevailing winds • Not too far from load • On a tall tower!Thursday, November 10, 2011
  34. 34. Siting the Highest Too far from loads point wind turbine • The highest point • Open to prevailing winds • Not too far from load • On a tall tower!Thursday, November 10, 2011
  35. 35. Choosing AC vs. DC • For a wind turbine installed far from the load normally the battery voltage will be as high as possible (48V) • If not enough - using an DC-AC inverter at the tower makes sense • Allows to work at 230 volts, and therefor less current • Losses are proportional to the current squared • Benefit: Allows to work with regular 230V AC loadsThursday, November 10, 2011
  36. 36. Choosing AC vs. DC • But cost of DC-AC inverter can be substantial • Alternative - site wind turbine close to load • Shorter cables - less loss • Downside: only DC loadsThursday, November 10, 2011
  37. 37. Conservative estimate of monthly electricity production • Assuming efficiency is 15% (see previous lecture for more refined estimate by Paul Gipe) D × V ⎡ kWh ⎤2 3 • E= 10 ⎢ month ⎥ ⎣ ⎦ V = average wind speed [m/s] D = diameter [m]Thursday, November 10, 2011
  38. 38. Estimating the loads • What the wind shouldn’t power: • Electric heaters • Electric cookers • For whom will the system be designed? • Single household • Several householdsThursday, November 10, 2011
  39. 39. Single householdThursday, November 10, 2011
  40. 40. Single household Rule of thumb - battery charging lossesThursday, November 10, 2011
  41. 41. Breaking down the load for a typical dayThursday, November 10, 2011
  42. 42. 3 households sharing a turbineThursday, November 10, 2011
  43. 43. 3 households sharing a turbineThursday, November 10, 2011
  44. 44. 3 households sharing a turbineThursday, November 10, 2011
  45. 45. 3 households sharing a turbineThursday, November 10, 2011
  46. 46. Sizing the turbine In an ideal world - 1. Identify wind resource 2. Identify electricity needs 3. Size turbine accordingly 4. Size battery bank according to measured wind patternThursday, November 10, 2011
  47. 47. Sizing the turbine for our two examplesThursday, November 10, 2011
  48. 48. Sizing the turbine for our two examples Enough spare energyThursday, November 10, 2011
  49. 49. Sizing the turbine for our two examples Not enough energyThursday, November 10, 2011
  50. 50. Sizing the battery • The battery is charged and discharged over a period of hours or days. • This is a cycle • Two parameters important in a battery life: • Number of cycles • The depth of dischargeThursday, November 10, 2011
  51. 51. Sizing the batteryThursday, November 10, 2011
  52. 52. Sizing the batteryThursday, November 10, 2011
  53. 53. Sizing the batteryThursday, November 10, 2011
  54. 54. Sizing the Battery • Calculate Ep, the daily consumption in Wh (for example Ep = 400 Wh/day) • Choose N, number of days of autonomy, typically 3-5 days (for example N = 3 days) • Choose maximum allowable depth of discharge, D (for example D = 0.5, which means 50%) • Choose U, battery voltage (typically 12,24 or 48 volts) (for example U = 12V)Thursday, November 10, 2011
  55. 55. Sizing the Battery Calculate C, battery capacity: • Calculate Ep, the daily consumption in Ep × N Wh C= [Ah] (for example Ep = 400 Wh/day) D ×U 400 × 3 • Choose N, number of days of autonomy, = = 200[Ah] typically 3-5 days (for example N = 3 days) 0.5 × 12 • Choose maximum allowable depth of discharge, D (for example D = 0.5, which means 50%) • Choose U, battery voltage (typically 12,24 or 48 volts) (for example U = 12V)Thursday, November 10, 2011
  56. 56. Cost of wind turbine - 2 meter diameter, 100 watt ratedThursday, November 10, 2011
  57. 57. Economics • Financing ownership by battery charging services • Current batteries are 60 Ah car batteries (DOD 50%) • To charge battery (with efficiency of charging loss of 25%) 0.5X60X12X1.25 = 450 Wh • 2 meter diameter at 3.5 m/s site produces 17 kWh/ month or 600 Wh/day on average • Therefor one battery charged per day • charging 1 day a week for the owner, and the rest for customersThursday, November 10, 2011
  58. 58. EconomicsThursday, November 10, 2011
  59. 59. Final system componentsThursday, November 10, 2011
  60. 60. Final system components Sizing according to local need and wind resourceThursday, November 10, 2011
  61. 61. Final system componentsThursday, November 10, 2011
  62. 62. Final system components Sizing according to wind variability and “spares” requirementThursday, November 10, 2011
  63. 63. Final system componentsThursday, November 10, 2011
  64. 64. Final system components For an AC system - according to maximum loadThursday, November 10, 2011
  65. 65. Final system componentsThursday, November 10, 2011
  66. 66. Small wind turbine marketThursday, November 10, 2011
  67. 67. WT brochure Proven WT6000 6kW Wind Turbine Proven TM900 9m (or TM1500 15m) Self-Supporting Mast            Performance Cut-In Wind Speed 2.5 metres/second (5.6 mph) Cut-Out Wind Speed none Rated Wind Speed 12 metres/second (25 mph) Rotor • Type Down-wind, Self-Regulating Includes many details Number of Blades 3, Flexible Rotor Diameter 5.6 metres Blade Material Wood/Epoxy/PU Generator Type Brushless, Direct Drive, • Permanent Magnet Most important parameter - (No Gear-Box, Zero Maintenance) Output 48V/120V/240V/300V 3-phase AC 7000 (25Hz nom) 6000 Rated RPM 200 nominal diameter, or swept area 5000 Rated Power 6000 Watts Power Output (Watts) 4000 3000 Annual Output 7000-18 000 kWh depending on site 2000 1000 TM900 Mast 0 Type Self supporting/Tilt Down. Hub Height 9m • 0 5 10 15 20 Wind speed in m etres/second (m ultiply by 2.2 for m .p.h.) Foundations 35 Newton Concrete Pad 2.5 x 2.5 x 1 m Make sure is intended for Rotor Speed Control Tube ∅ 175 mm top A/F 350 mm bottom A/F 530 mm square mast base battery charging Above 12m/s (25mph) the blade TM1500 Mast pitch is automatically adjusted to Type Self supporting/Tilt Down. maintain 200 rpm and full output Hub Height 15m Foundations 35 Newton Concrete Pad 3 x 3 x 1.2 m High Build Quality Tube ∅ 200 mm top A/F All components are hot-dipped 440 mm bottom A/F • galvanised steel, stainless steel or 750 mm x 739mm mast base plastic. Must have aerodynamic Low Speed Equals Durability Low rotor speed (half the speed of Noise <45dB <60dB (approximate) At 5m/s At 20m/s control option comparable machines) ensures 70-80dB Car 15m away at approx 40 mph. extended durability of blades and bearings. It also means that Weight Proven WTs are the quietest in the world! WT6000 500 kg TM900/6000 360 kg (+ 70kg gin pole) TM1500/6000 656 kg (+ 240kg gin pole) z : a l l wi n d t u r b s a l e s l i t m a n u a l w t 6 0 0 0 s s s p e c s h ee t s 6 0 0 0 s s 0 0 1 r e v 2 . d o cThursday, November 10, 2011
  68. 68. Small wind turbine marketThursday, November 10, 2011
  69. 69. Source - American magazine. 2 mph = 1 m/s Small wind turbine marketThursday, November 10, 2011
  70. 70. Small wind turbine marketThursday, November 10, 2011
  71. 71. Most important parameter Small wind turbine marketThursday, November 10, 2011
  72. 72. Small wind turbine marketThursday, November 10, 2011
  73. 73. Case studiesThursday, November 10, 2011
  74. 74. Thursday, November 10, 2011
  75. 75. Thursday, November 10, 2011
  76. 76. Thursday, November 10, 2011
  77. 77. Thursday, November 10, 2011
  78. 78. Thursday, November 10, 2011
  79. 79. Thursday, November 10, 2011
  80. 80. Thursday, November 10, 2011
  81. 81. Thursday, November 10, 2011
  82. 82. small wind: 0.2$-1.15$ / kWh solar PV: 1.21$ / kWhThursday, November 10, 2011
  83. 83. African Wind PowerThursday, November 10, 2011
  84. 84. • Example of technology transfer African Wind PowerThursday, November 10, 2011
  85. 85. • Example of technology transfer • Turbines now installed from Africa to Antarctica! African Wind PowerThursday, November 10, 2011
  86. 86. AWP - Zimbabwe - Masampa Village Lake Kariba • AWP3.6 - 48V 13.5M tilt up tower, 275Ahr 48V Battery bank, 3KW sine wave inverter, 12V battery charging station.Thursday, November 10, 2011
  87. 87. AWP - Zimbabwe - Masampa Village Lake Kariba • AWP3.6 - 48V 13.5M tilt up tower, 275Ahr 48V Battery bank, 3KW sine wave inverter, 12V battery charging station. • This fishing co-operative village is on the shores of Lake Kariba, 45Km by boat from the nearest town. Crocodiles inhabit the shore line and Hippos amble through the village at night while foraging ( startling a hippo is not good for your health). With funds provided by the Dutch government via the NGO ZERO, AWP implemented the entire project in all its stages: • (1) Initial location of the people in need • (2) discussions with the village committee • (3) resulting in motivation of the villagers to contribute labour to the installation, transportation of all materials to site, construction and commissioning • (4) and finally training of operators. • The system provides lighting for the main thoroughfares and also a popular 12v car battery charging center which draws customers from a 20 Km radius. Income from this activity is used for village development.Thursday, November 10, 2011
  88. 88. WindAid - PeruThursday, November 10, 2011
  89. 89. Thursday, November 10, 2011
  90. 90. Thursday, November 10, 2011
  91. 91. Thursday, November 10, 2011
  92. 92. Thursday, November 10, 2011
  93. 93. Thursday, November 10, 2011
  94. 94. Thursday, November 10, 2011
  95. 95. Thursday, November 10, 2011
  96. 96. Thursday, November 10, 2011
  97. 97. Thursday, November 10, 2011
  98. 98. Thursday, November 10, 2011
  99. 99. Thursday, November 10, 2011
  100. 100. Thursday, November 10, 2011
  101. 101. Comet-METhursday, November 10, 2011
  102. 102. Comet-METhursday, November 10, 2011
  103. 103. Comet-METhursday, November 10, 2011
  104. 104. Comet-METhursday, November 10, 2011
  105. 105. Comet-METhursday, November 10, 2011
  106. 106. Comet-ME • The systems are designed for producing 2-3 kWh/ day for a large beduin family. • Systems are DIY wind turbines and solar PV panels • Systems used for powering: • Lights • Refrigirator • Butter churn • TV • Cellphone charging • Costs are between 5000$-8000$Thursday, November 10, 2011
  107. 107. ResourcesThursday, November 10, 2011
  108. 108. ResourcesThursday, November 10, 2011
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