Publisher: Earthscan, UK Homepage: www.earthscan.co.uk/?tabid=101808 Energy and the New Reality, Volume 2: C-Free Energy Supply Chapter 7: Ocean Energy L. D. Danny Harvey harvey@geog.utoronto.ca Publisher: Earthscan, UK Homepage: www.earthscan.co.uk/?tabid=101808 This material is intended for use in lectures, presentations and as handouts to students, and is provided in Powerpoint format so as to allow customization for the individual needs of course instructors. Permission of the author and publisher is required for any other usage. Please see www.earthscan.co.uk for contact details.

Figure 7.1 Wave power density (kW per m of coastline) along the world’s coastline Source: Boud (2002, Status and Research and Development Priorities 2003, Wave and Marine Current Energy, International Energy Agency, Implementing Agreement on Ocean Energy Systems)

Figure 7.2a A shoreline wave energy conversion device Source: Khan and Bhuyan (2009, Ocean Energy: Global Technology Development and Status, IEA-OES Document T0104 )

Figure 7.2b A floating wave energy conversion device Source: Khan and Bhuyan (2009, Ocean Energy: Global Technology Development and Status, IEA-OES Document T0104 )

Figure 7.3 Rotation of the Earth and moon around a common centre and the resulting bulge in the ocean surface due to the resulting centrifugal force Source: Elliott (1996, Renewable Energy: Power for a Sustainable Future, Oxford University Press, Oxford)

Figure 7.4 The variation in tidal range within the Severn Estuary of the UK Source: Elliott (1996, Renewable Energy: Power for a Sustainable Future, Oxford University Press, Oxford)

Figure 7.5a Variation in water level outside and inside a tidal barrage (dam) designed to produce power only during the flood flow Source: Elliott (1996, Renewable Energy: Power for a Sustainable Future, Oxford University Press, Oxford)

Figure 7.5b Variation in water level outside and inside a tidal barrage (dam) designed to produce power only during the ebb flow Source: Elliott (1996, Renewable Energy: Power for a Sustainable Future, Oxford University Press, Oxford)

Figure 7.5c Variation in water level outside and inside a tidal barrage (dam) designed to produce power during both the flood and ebb flows Source: Elliott (1996, Renewable Energy: Power for a Sustainable Future, Oxford University Press, Oxford)

Figure 7.6a A bulb tidal turbine Source: Boud (2002, Status and Research and Development Priorities 2003, Wave and Marine Current Energy, International Energy Agency, Implementing Agreement on Ocean Energy Systems)

Figure 7.6b A stratflo tidal turbine Source: Boud (2002, Status and Research and Development Priorities 2003, Wave and Marine Current Energy, International Energy Agency, Implementing Agreement on Ocean Energy Systems)

Figure 7.6c A tubular tidal turbine Source: Boud (2002, Status and Research and Development Priorities 2003, Wave and Marine Current Energy, International Energy Agency, Implementing Agreement on Ocean Energy Systems)

Figure 7.7 Potential sites for tidal barrages along with the tidal range (m) and potential installed power capacity (GW) Source: Elliott (1996, Renewable Energy: Power for a Sustainable Future, Oxford University Press, Oxford)

Figure 7.8 Proposed tidal current energy devices Source: Boud (2002, Status and Research and Development Priorities 2003, Wave and Marine Current Energy, International Energy Agency, Implementing Agreement on Ocean Energy Systems)

Figure 7.9 Proposed tidal-current turbines Source: www.e-tidevannsenergi.com

Figure 7. 10 Vertical variation in temperature in the upper 1 Figure 7.10 Vertical variation in temperature in the upper 1.5 km of the ocean at various tropical and subtropical locations Source: www.xenesys.com

Figure 7.11 Geographical variation in the difference in temperature between the ocean surface and ‘deep’ water (typically at a depth of 1000 m) Source: www.xenesys.com

Figure 7.12 A closed-cycle OTEC process based on the Rankine cycle Source: Khan and Bhuyan (2009, Ocean Energy: Global Technology Development and Status, IEA-OES Document T0104 )

Figure 7.13 A pressure-retarded osmosis process for generating electricity from a salinity gradient Source: Khan and Bhuyan (2009, Ocean Energy: Global Technology Development and Status, IEA-OES Document T0104 )