1 / 74

Introduction to Hydro Power 15 April 2009 Monterey Institute for International Studies

Introduction to Hydro Power 15 April 2009 Monterey Institute for International Studies. Chris Greacen chris@palangthai.org. Outline. Solar, wind, hydro – brief comparison Hydro system overview Some examples from Thailand and elsewhere Site assessment Head Flow Penstock length

chenoa
Download Presentation

Introduction to Hydro Power 15 April 2009 Monterey Institute for International Studies

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction toHydro Power 15 April 2009 Monterey Institute for International Studies Chris Greacen chris@palangthai.org

  2. Outline • Solar, wind, hydro – brief comparison • Hydro system overview • Some examples from Thailand and elsewhere • Site assessment • Head • Flow • Penstock length • Transmission line length • Civil works • Mechanical • Electrical

  3. Sun, Wind, & Water

  4. Micro-hydropower overview Source: Inversin, A. R. (1986). Micro-Hydropower Sourcebook.

  5. Thai Potential: 1000s of projects - 700 MW (?) Mae Kam Pong, Chiang Mai DEDE + community 40 kW $130,000 cost Sell electricity to PEA – $13,000 per year

  6. Huai Krating, Tak Power: 3 kW Head: 35 meter Flow: 20 liters/second Cost: <$6,000 (turbine - $700 baht)

  7. Kre Khi village, Tak Province 1 kW for school, clinic, church Cost: <$3,500 (turbine $250) Head: 10 meters Flow: 15 lit/sec

  8. Mae Klang Luang, Chaing Mai 200 watts $120 (turbine: $90) Installed: 2007 Head: 1.7 meters

  9. Micro-hydroelectricity: Estimating the energy available Power = 5 x height x flow height meters liters per second Watts Image Source: Inversin, A. R. (1986). Micro-Hydropower Sourcebook.

  10. Measuring height drop (head) • Site level • Pressure gauge

  11. Sight level method

  12. Hose & Pressure Gauge • Accurate and simple method. • Bubbles in hose cause errors. • Gauge must have suitable scale and be calibrated. • Use hose a measuring tape for penstock length. • Feet head = PSI x 2.31 H1

  13. Measuring Flow • Bucket Method • Float Method design flow = 50% of dry-season flow

  14. Bucket Method

  15. Float Method Flow = area x average stream velocity

  16. Civil Works – some golden rules • Think floods, landslides • Think dry-season. • Try to remove sediment • Maximize head, minimize penstock • “wire is cheaper than pipe” Image source: Inversin, A. R. (1986). Micro-Hydropower Sourcebook.

  17. Source: Inversin, A. R. (1986). Micro-Hydropower Sourcebook.

  18. Weir A Sluice allows sediment removal.

  19. Silt Basin Trash Rack Intake Head Race Penstock Weir Locating the Weir & Intake

  20. Intake directly to penstock If spring run-off sediment is not severe, the penstock may lead directly from the weir. Screened Intake Weir Penstock

  21. Side intake

  22. Trash rack: keeps the big stuff out

  23. Screens Screen mesh-size should be half the nozzle diameter. A self-cleaning screen design is best. The screen area must be relatively large. Screen Head Race Penstock Silt Basin

  24. Source: Inversin, A. R. (1986). Micro-Hydropower Sourcebook.

  25. Power Canal (Head Race) It may be less expensive to run low pressure pipe or a channel to a short penstock. Head Race 6” Penstock 4” Penstock

  26. Forebay (Silt basin) • Located before penstock • Large cross-sectional area, volume  Water velocity reduced  sediment (heavier than water but easily entrained in flow) has opportunity to drop out.

  27. Source: Inversin, A. R. (1986). Micro-Hydropower Sourcebook.

  28. Penstocks A vent prevents vacuum collapse of the penstock. Valves that close slowly prevent water hammer. Anchor block – prevents penstock from moving Vent Valve Pressure Gauge Valve Penstock Anchor Block

  29. Penstock diameter Hazen-Williams friction loss equation: headloss friction (meters) =(10.674*(F/1000)^1.85)/(CoefFlow^1.85*D^4.87)*L Where: F = flow (liters/sec) CoefFlow = 150 for PVC D = penstock diameter (mm)

  30. Penstock materials Poly vinyl chloride (PVC) Polyethylene (PE) Aluminium Steel

  31. Anchor and Thrust Blocks

  32. Source: Inversin, A. R. (1986). Micro-Hydropower Sourcebook.

  33. Locating the Powerhouse • Power house must be above flood height. • Locate powerhouse on inside of stream bends. • Use natural features for protection.

  34. Micro-hydro technology Centrifugal pump Pelton Turgo Crossflow Kaplan

  35. Turbine application http://www.tycoflowcontrol.com.au/pumping/welcome_to_pumping_and_irrigation/home4/hydro_turbines/turbine_selection (April 18, 2003)

  36. Efficiency and Flow 100% Pelton and Turgo Crossflow Propeller 50% Efficiency Francis 0% 0 0.2 0.4 0.6 0.8 1.0 Fraction of Maximum Flow

  37. Generators • Permanent magnet • Wound rotor synchronous • Induction (Asynchronous)

  38. Permanent Magnet Generator • Rotor has permanent magnets • Advantages • No brushes • Efficient • Disadvantages • Generally limited in size to several kW • field not adjustable (except ESD) • Some do AC • Some do AC and rectify to DC • Some do both

  39. Adjustable permanent magnet generator

  40. DC Alternator (automotive) • Produces rectified alternating current. • Readily available. • Easy to service. • Brushes need replacing. • A rheostat controls excitation.

  41. DC Alternator (automotive) • May be rewound for lower rpm at low head. • The field may need a battery boost to start. • Use high voltage ac output with a step-down transformer and rectifier for long transmission distance.

  42. (wound rotor) Synchronous Generator • Used in many all stand-alone applications. • Single phase up to 10 kW. • 3-phase up to >100,000 kW • Advantage: • Industrial standard • Frequency and voltage regulation • Disadvantage • Wound rotor – not tolerant to overspeed • Harder to connect to grid

  43. (wound rotor) Synchronous Generator • Most large machines use field coils to generate the magnetic field. • Rotating magnetic field induces alternating current in stator windings. Rectifier Stator Output Winding Exciter Field Winding Rotor Field Winding Exciter Winding AVR

More Related