1. Introduction to Microhydro 15 Apr 2012 Monterey Institute for International Studies Introduction to Microhydro 15 Apr 2012 Monterey Institute for International Studies Chris Greacen chris@palangthai.org

2. Outline • Micro-hydro system overview • Site assessment – Head – Flow • Civil works • Mechanical • Electrical

3. Sun, Wind, & Water

4. Financial analysis pico-hydropower ESMAP, 2005 4 Mattijs, Smits, presentation at Chulalungkorn University

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

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

7. Abney level (the method we’ll be using today)

8. Sight level method

9. 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 H1H1

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

11. Bucket Method ( probably the method we’ll be using today )

12. Float Method Flow = area x average stream velocity

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

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

15. Weir A Sluice allows sediment removal.

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

19. Side intake

20. 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 PenstockHead Race Silt Basin

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

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

25. 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.

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

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

28. Penstock diameter Hazen-Williams friction loss equation: • C = roughness coefficient

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

30. Anchor and Thrust Blocks

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

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

33. Micro-hydro technology PeltonTurgoCrossflowKaplan Centrifugal pump

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

35. Efficiency and Flow 0.20.80.60.41.0 Fraction of Maximum Flow Efficiency 50% 0 0% 100% Pelton and Turgo Crossflow Francis Propeller

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

37. Thank you For more information, please contact chris@palangthai.org chris@palangthai.org This presentation available at: www.palangthai.org/docs