1. Ocean Renewable Energy: Overview & Progress Moo-Hyun Kim Professor Ocean Engineering Program Dept. of Civil Engineering Texas A&M University

2. Fossil Fuels US oil consumption = 25% US oil consumption = 25% US oil production = 3% US oil production = 3% More than 70% oil imported More than 70% oil imported Energy Independence: #1 Economy, Security Energy Independence: #1 Economy, Security

3. Ocean Renewable Energy Wave Wave Wind Wind Current Current Tide Tide OTEC OTEC Salinity (Osmotic Pressure) Salinity (Osmotic Pressure)

4. Ex. Relative Cost (cents/kwh) Coal & Oil 3-5 Nuclear11-14 Hydro4-10 bio6-11 Wind 5-7 (6-8) Wave7-9 Solar10-15

5. Wave & tidal power distribution

6. Man-made Tidal Energy Plant France La Rance dam and typical turbine/generator configuration: environmental concern

7. Natural Tidal-Current Energy Promising West Coast Sites

8. Natural Current Power: Korea

11. 2TW of energy, the equivalent of twice the world’s electricity production, could be harvested from the world’s oceans Wave Enegy Resource

12. Wave Energy Conversion Oscillating Water Column Fixed Oscillating Water Column Attenuator Floating Attenuator Overtopping Floating Overtopping FloatingPointAbsorber

13. Land-based OWC Land-based OWC Oscillating Water Column Oscillating Water Column Islay, Scotland

15. Wind Energy

16. 2007 Wind Energy Use Worldwide Wind Total=74 GW Worldwide Wind Total=74 GW Less than 1% of the global electricity use Rapidly Growing Green-Wind Industry: Annual Growth Rate = 25%

17. Winner of 2006: US, Ger, India, Spain

18. Texas Wind Energy Projection

19. Wind Energy Pros & Cons Pros Endless/renewable Endless/renewable No CO 2 Emission No CO 2 Emission No Land Space (Offshore) No Land Space (Offshore) No cooling, No pollution, No waste No cooling, No pollution, No wasteCons Noise, Shade, Unsightly, Birds Noise, Shade, Unsightly, Birds Survive? Severe Environment (Offshore) Survive? Severe Environment (Offshore)

20. Wind-Energy Turbine

22. Feasibility/Economy grows with blade size Blade Dia (m) Hub height (m) Power (MW) Ref (# of homes) 70551.6500 100703.61200 1208051600

23. What 500-MW Wind-E Farm Can Do! Provide clean energy for 160K homes Provide clean energy for 160K homes Eliminating (per year) Eliminating (per year) - 60-mil lb of CO 2 (leading green-house gas) - 130K lb of NOx (main comp. of smog) - 300K lb of Sulfur Dioxide (leading precursor of acid rain)

24. Why Offshore Wind-Farm? Future Stronger-steadier quality wind (20-30% better wind, 30-40% more cost) Stronger-steadier quality wind (20-30% better wind, 30-40% more cost) More space More space Easier regulatory approval Easier regulatory approval Less noise constraint (operable at higher speed) Less noise constraint (operable at higher speed) No visual pollution No visual pollution

25. Offshore Wind Energy: stronger-steadier REpower - Scotland Norskhydro - Norway Fixed (tower) 44m depth Floating (spar) >200m 5mw 3mw demo unit underway 126m rotor diameter 90m rotor diameter

26. Various Types of Floating WF

27. Status of Offshore Wind  Offshore ~900 MW of 75,000 MW+ world-wide – less than 2%  11,000 MW+ offshore is projected for 2010 Current Future - 2010

28. Wind Energy Cost Trends 1981: 40 cents/kWh Increased Turbine Size R&D Advances Manufacturing Improvements 2007: 5 - 9 cents/kWh 2012: 3.6 cents/kWh? 2007: 9-12 cents/kWh 2014: 5 cents/kWh Multi-megawatt Turbines High reliability systems Infrastructure Improvements Land-based Class 4 Offshore Class 6

29. KEY: Synergy & Storage 3 times more valuable if provided on demand

30. Synergy with Fish Farm

36. Structural Failure!

37. Floating Wind-F: Dynamic/Fatigue Failure Rotor dynamics and control Rotor dynamics and control Platform motions and mooring dynamics Platform motions and mooring dynamics

38. Questions?