Are Nearly all Tidal Stream Turbines Designs Wrong for the Pentland Firth?

1. Are Nearly all Tidal Stream Turbines Designs Wrongfor the Pentland Firth? Stephen Salter Institute for Energy Systems University of Edinburgh S.Salter@ed.ac.uk www.see.ed.ac.uk/~shs

2. No names, no pack drill.

3. EWTEC Patras 1998 Edinburgh vertical-axis, variable-pitch with rim power take off.

4. . . . just like wind turbines but under water. Frederick Lanchester 1868-1946 Albert Betz 1885-1968

5. Turbine in a duct:

6. Open flow field Duct

9. McAdam RA, Houlsby GT, Oldfield MLG. Experimental measurements of the hydrodynamic performance and structural loading of the transverse horizontal axis water turbine: part 1. Renewable Energy vol. 59 pp. 105-114. 2013

10. O’Doherty DM. Mason-Jones, Morris, O’DohertyT, Bryne, Pricket, Grosvenor. Interaction of Marine Turbines in Close Proximity. EWTEC 2011

14. NASA

15. EWTEC Patras 1998 Edinburgh vertical-axis, variable-pitch with rim power take off.

16. Flow Impedance The determination of the water to flow despite the introduction of obstacles.

17. Flow Impedance The determination of the water to flow despite the introduction of obstacles. Ratio of head increase to flow-rate reduction.

18. Flow Impedance The determination of the water to flow despite the introduction of obstacles. Ratio of head increase to flow-rate reduction.

19. Flow Impedance The determination of the water to flow despite the introduction of obstacles. Ratio of head increase to flow-rate reduction.

20. Flow Impedance The determination of the water to flow despite the introduction of obstacles. Ratio of head increase to flow-rate reduction.

21. Flow Impedance The determination of the water to flow despite the introduction of obstacles. Ratio of head increase to flow-rate reduction.

22. Laminaria Hyperborea (kelp) are found along the edges of the Pentland Firth at depths up to 30 m. Length can reach 3.5 metres. Cf = ?

23. 68 mm bob Pentland bed stills. P Hayes. Fisheries Research Aberdeen 2006-8

24. Friction coefficients for Fshear = 0.5ρ U2 Cf 6.165 TW x 0.04 = 247 GW

28. GOOGLE IMAGES MoD order the stretcher bearers to be at the same end ?

33. No tip-to-hub velocity reduction No squeezing torque through a bearing. On-line shirt-sleeve access at the surface. Thousands of force lines. Contact-free gutter seal. Lots of space.

38. Are Nearly all Tidal Stream Turbines Designs Wrongfor the Pentland Firth? Stephen Salter Institute for Energy Systems University of Edinburgh S.Salter@ed.ac.uk www.see.ed.ac.uk/~shs

39. Google images

40. Google images Speed up x 30 Range up x 6000 Payload up x 20,000 Cost per ton-mile down ÷ 100

41. Something for the simpletons

43. R.A. McAdam , G.T. Houlsby , M.L.G. Oldfield Structural and Hydrodynamic Model Testing of the Transverse Horizontal Axis Water TurbineEWTEC 2011

44. O’Doherty DM. Mason-Jones A, Morris C, O’DohertyT, Bryne C, Pricket PW, Grosvenor RI. Interaction of marine turbines in close proximity. EWTEC 2011

46. No names, no pack drill.

49. R.A. McAdam, G.T. Houlsby, M.L.G Oldfield. Structural and Hydrodynamic Model Testing of the Transverse Horizontal Axis Water Turbine. EWTEC 2011