1. Second Oxford Tidal stream Workshop 2013 Are Nearly all Tidal Stream Turbines Designs Wrong? Stephen Salter Institute for Energy Systems University of Edinburgh S.Salter@ed.ac.uk www.see.ed.ac.uk/~shs S.Salter@ed.ac.uk

2. No names, no pack drill. S.Salter@ed.ac.uk

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

4. Unswept flow passage ≡ leaky pipes ≡ Vortex wake pollution ≡ Ignorance of flow angles

5. 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

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

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

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

9. Open flow field Duct

11. Bending moment at blade root http://www.google.co.uk/search?q=Tidal+stream+turbine+Alstom&hl=en&client=safari&rl s=en&tbm=isch&tbo=u&source=univ&sa=X&ei=BOBOUbPSJY6o0wXh2ICIBw&ved=0CE IQsAQ&biw=1042&bih=1505

12. GOOGLE IMAGES

14. NASA

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

17. Pitch variation gives control of rotor forces Contra-rotation cancels cross force and torque reaction in wake

22. Work goes through restricted passage to congested generation space

31. Second Oxford Tidal stream Workshop 2013 Are Nearly all Tidal Stream Turbines Designs Wrong? Stephen Salter Institute for Energy Systems University of Edinburgh S.Salter@ed.ac.uk www.see.ed.ac.uk/~shs

32. Google images

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

34. Something for the simpletons

35. 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 = ? Google images.

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

37. Friction coefficients for Fshear = 0.5 ρ U 2 Cf 6.165 TW x 0.04 = 247 GW

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