reading

Cover
Title Page
List of Contributors
Foreword
Acknowledgements
1 Introduction
1. 1.1 Background
2. 1.2 History of Wave and Tidal Energy
3. 1.3 Unknowns and Challenges Remaining for Wave and Tidal Energy
4. 1.4 Synopsis
5. References
2 The Marine Resource
1. 2.1 Introduction
2. 2.2 The Wave Resource
3. 2.3 The Tidal Stream Resource
4. Acknowledgements
5. References
3 Wave Energy Technology
1. 3.1 Introduction
2. 3.2 Fundamentals
3. 3.3 Hydrodynamics of Wave Energy Conversion
4. 3.4 Classification of Wave Energy Converters
5. 3.5 Oscillating Water Columns
6. 3.6 Overtopping Systems
7. 3.7 Oscillating Bodies
8. 3.8 Other Technologies
9. 3.9 The Wave Energy Array
10. References
4 Tidal Energy Technology
1. 4.1 General Introduction
2. 4.2 Location of Operation
3. 4.3 Environmental Impacts
4. 4.4 Tides
5. 4.5 Tidal Range Generation
6. 4.6 Tidal Stream
7. 4.7 Types of Devices
8. 4.8 Oscillating Hydrofoils
9. 4.9 Venturi Effect Devices
10. 4.10 Other Devices
11. 4.11 Computational Fluid Dynamics
12. 4.12 Security, Installation and Maintenance
13. 4.13 Worked Examples
14. References
5 Device Design
1. 5.1 Standards and Certification in Marine Energy
2. 5.2 Reliability
3. 5.3 Moorings and Anchors
4. 5.4 Foundations
5. References
6 Power Systems
1. 6.1 Introduction to Power Take-Off Systems
2. 6.2 Electrical Generators
3. 6.3 Turbines for WEC Power Take-Off
4. 6.4 Hydraulic Power Transmission Systems
5. 6.5 Hydraulic PTO Designs for WECs
6. 6.6 Direct Mechanical Power Take-Off
7. 6.7 Control for Maximum Energy Capture
8. 6.8 Electrical Infrastructure and Grid Integration
9. 6.9 Summary of Challenges for PTO Design and Development
10. References
7 Physical Modelling
1. 7.1 Introduction
2. 7.2 Device Development and Test Planning
3. 7.3 Scaling and Similitude
4. 7.4 Model Design and Construction
5. 7.5 Fixing and Mooring
6. 7.6 Instrumentation
7. 7.7 Model Calibration
8. 7.8 Modelling the Environment
9. 7.9 Test Facilities
10. 7.10 Recommended Tests
11. References
8 Numerical Modelling
1. 8.1 Introduction
2. 8.2 Review of Hydrodynamics
3. 8.3 Numerical Modelling Techniques
4. 8.4 Numerical Modelling of Water Waves
5. 8.5 Commonly Used Open-Source Software
6. 8.6 Applicability of Numerical Models in MRE
7. References
9 Environmental Effects
1. 9.1 Introduction
2. 9.2 Wave Farm Effects on the Wave Field
3. 9.3 Wave Farm Effects on Coastal Processes
4. 9.4 Tidal Stream Farm Effects on Hydrodynamics and Sedimentary Processes
5. 9.5 Marine Biota
6. 9.6 The Environmental Impact Assessment
7. References
10 Consenting and Legal Aspects
1. 10.1 Introduction
2. 10.2 International Law
3. 10.3 Regional Law
4. 10.4 EU Law and Policy
5. 10.5 National Consenting Systems
6. 10.6 Gaps and Opportunities
7. Acknowledgement
8. References
11 The Economics of Wave and Tidal Energy
1. 11.1 Individual Costs
2. 11.2 Levelised Cost
3. 11.3 Externalities
4. References
12 Project Development
1. 12.1 Introduction
2. 12.2 Alstom Ocean Energy OCEADE™ Tidal Stream Turbine: The Route to Commercial Readiness
3. 12.3 Seabased Wave Energy Converter
4. 12.4 Lake Sihwa Tidal Power Plant, Korea
5. 12.5 Mutriku Wave Power Plant
6. References
13 Regional Activities
1. 13.1 Europe
2. 13.2 North America
3. 13.3 Latin America
4. 13.4 Asia-Pacific
5. 13.5 China
6. References
Epilogue: The Future of Wave and Tidal Energy
Index
End User License Agreement

List of Tables

Chapter 02
1. Table 2.1 Tidal constituents at the mouth of the Severn Estuary [44].
2. Table 2.2 Correlation coefficient (R) and RMSE values of predicted and measured currents.
Chapter 03
1. Table 3.1 Theoretical limits to capture width [42–44].
Chapter 04
1. Table 4.1 Ranked UK possible sites for tidal stream energy.
Chapter 05
1. Table 5.1 Probability of failure bands and corresponding frequencies.
2. Table 5.2 Input parameters typically required by mooring system software.
3. Table 5.3 Typical frequency-dependent hydrodynamic parameters calculated by potential theory codes.
4. Table 5.4 Selected properties of steel and several synthetic fibre materials [47].
5. Table 5.5 Compatibility matrix for MRE foundations based on support structure and seafloor type (soil suitability for pile and GBS foundations from [59] and suction caissons from [60]).
6. Table 5.6 Typical soil index properties and laboratory test methods.
7. Table 5.7 Soil–foundation interaction performance metrics based on [59, 60].
8. Table 5.8 Constitutive soil models used in conventional foundation analysis.^a
Chapter 06
1. Table 6.1 Evaluation of common types of generators used for wave and tidal energy. A grade point system is used in which 1 is the worst and 5 is the best [10].
2. Table 6.2 Pump types and characteristics.
Chapter 07
1. Table 7.1 Technical output of TRLs 1–5 and the three first development phases of an MRE, based on [1].
2. Table 7.2 Geometric similitude scaling ratios for Froude and Reynolds criteria between model and prototype.
3. Table 7.3 Standard tests for wave energy devices.
4. Table 7.4 Survivability tests for wave energy devices.
Chapter 08
1. Table 8.1 Values of model coefficients [8]
2. Table 8.2 Boundary conditions for the model [8].
3. Table 8.3 Values of model coefficients [8].
4. Table 8.4 Boundary conditions for the model [8].
5. Table 8.5 Boundary conditions for elliptic flows solved with RSM [8].
6. Table 8.6 Classification of physical behaviours for low Mach numbers [8].
7. Table 8.7 Physical processes according to the depth of the sea.
8. Table 8.8 Model applicability based on the governing equations for various physical processes.
9. Table 8.9 Efficiency of the numerical models.
10. Table 8.10 Suitability of numerical models for different aspects of MRE projects [4].
Chapter 09
1. Table 9.1 Model configurations, wave conditions and values of the transmission coefficient (α = angle between hulls; F = freeboard; H_s = significant wave height; T_e = energy period (in model values); K_t = transmission coefficient) [7].
2. Table 9.2 Case studies, wave conditions and wave farm configurations (H_s = significant wave height; T_e = energy period; θ = wave direction; CONF = configuration (I, II or BL, baseline)).
3. Table 9.3 Parameters of the case studies (d = farm-to-coast distance (– means no wave farm, i.e. the baseline case); h = reference water depth; H_s = significant wave height; T_e = energy period; θ = mean wave direction).
4. Table 9.4 FEA and NER factors for profiles P1 and P2 at different points in time: 1 month (M1), 3 months (M3) and 6 months (M6) into the study period.
5. Table 9.5 Wave conditions: significant wave height (H_s), peak period (T_p), direction (θ) and directional spreading (s), and wave transmission coefficient (K_t).
6. Table 9.6 Marine renewable energy environmental stressors occurring during the different phases of deployment.
7. Table 9.7 Examples of relevant environmental receptors that are usually considered during the EIA process of ocean energy projects. C: construction; O: Operation; D: Decommissioning.
8. Table 9.8 Ocean energy stressors and receptors during different project phases.
9. Table 9.9 Methods used to monitor MRE impacts on fish populations.
10. Table 9.10 Techniques for monitoring cetacean species in MRE parks.
11. Table 9.11 Techniques used for pinniped monitoring.
Chapter 10
1. Table 10.1 International legal instruments with possible implications for Ocean Energy developments.
2. Table 10.2 Estimation of total contribution (installed capacity, gross electricity generation) expected from ocean (wave and tidal) and offshore wind to meet the binding 2020 targets and the indicative interim trajectory for the shares of energy from renewable resources in electricity for 2015–2020.
3. Table 10.3 Qualitative descriptors used in determining GES under Annex I of the MSFD.
4. Table 10.4 Overall device/technology risk.
5. Table 10.5 Other applicable Federal Statutes and their possible implications for MHK projects.
Chapter 11
1. Table 11.1 Capital cost quotations used in previous studies.
2. Table 11.2 Operation and maintenance cost [37, 42–48].
Chapter 12
1. Table 12.1 Annual energy output of Lake Sihwa Tidal Power Plant.
2. Table 12.2 Power production in the first year of operation.
3. Table 12.3 Power production of the Mutriku wave energy plant exported to the grid (kWh, breakdown by month and year of operation.
Chapter 13
1. Table 13.1 National support schemes for MRE technologies [19].
2. Table 13.2 Chile’s marine energy development potential by region.
3. Table 13.3 Research projects for wave energy converters, Korea [296].
4. Table 13.4 Research projects for tidal energy, Korea [296].

List of Illustrations

Chapter 02
1. Figure 2.1 The so-called Death Coast (Costa da Morte) in Galicia, NW Spain: general map (above) and detailed map of the area around the nearshore hotspot (below), with average wave power values. The nearshore hotspot considered in Section 2.4 is depicted by a black circle.
2. Figure 2.2 Offshore resource characterisation matrix including wave power isolines for the Death Coast (Costa da Morte), Galicia, NW Spain. The numbers in the greyed squares represent the occurrence of the respective energy bins, expressed in hours in a typical year. The greyscale indicates the contribution of each energy bin to the annual resource.
3. Figure 2.3 Offshore resource characterisation matrix for the Death Coast (NW Spain), with improved resolution: 0.5 s (ΔT_e) × 0.5 m (ΔH_s).
4. Figure 2.4 Computational grid for the Death Coast case study. For the sake of clarity, only one in three nodes is represented.
5. Figure 2.5 Offshore resource characterisation matrix limited to the wave cases selected for propagation, i.e. 95% of the total resource.
6. Figure 2.6 Resource characterisation matrix at the nearshore hotspot in Figure 2.1.
7. Figure 2.7 Resource characterisation matrix at the nearshore hotspot in terms of mean wave direction and significant wave height (θ_m, H_s). A wave power rose is also included.
8. Figure 2.8 Resource characterisation matrix at the nearshore hotspot in terms of mean wave direction and energy period (θ_m, T_e). A wave power rose is also included.
9. Figure 2.9 The Severn Estuary and Bristol Channel (case study I).
10. Figure 2.10 Model validation: observed (gauge) and computed (model) time series of tidal levels at four stations in the Bristol Channel.
11. Figure 2.11 Annual tidal stream energy density (MWh m^–2) in the Severn Estuary and Bristol Channel (UK).
12. Figure 2.12 Ria de Ortigueira, Galicia (NW Spain).
13. Figure 2.13 Computational grid of Ria de Ortigueira (NW Spain).
14. Figure 2.14 TSE index in the inner estuary. The area with greatest potential for tidal stream exploitation between Pt. Postiña and Pt. Cabalar (Figure 2.13) is conspicuous in the graph.
15. Figure 2.15 Flow velocity at mid-flood and mid-ebb in the surface and bottom layers of the inner estuary, Ria de Ortigueira (NW Spain).
Chapter 03
1. Figure 3.1 Early UK wave energy converter concepts. (a) Salter’s duck [3] (b) Cockerell raft [5] with kind permission of dover publications (c) Bristol cylinder [6] (d) NEL OWC [7] with kind permission of dover publications.
2. Figure 3.2 Early Norwegian wave energy converter concepts. (a) TAPCHAN [12] (b) Kværner OWC [13].
3. Figure 3.3 Six degrees of freedom motion of a floating body.
4. Figure 3.4 Schematic of heaving buoy.
5. Figure 3.5 Schematic of wavemaker.
6. Figure 3.6 Wave energy classification [14].
7. Figure 3.7 Schematic of oscillating water column.
8. Figure 3.8 Shoreline OWCs. (a) Pico, Azores, Portugal [55] (b) Limpet, Islay, Scotland [54] (c) Mutriku Spain [67.]
9. Figure 3.9 Floating OWCs. (a) Oceanlinx (Australia) [78] (www.oceanlinx.com) (b) Mighty whale, Gokasho Bay (Japan) [59] (c) The OE12 quarter-scale device on test at sea in Galway Bay (Ireland).
10. Figure 3.10 Schematic of floating OWC.
11. Figure 3.11 Seawave Slot-Cone Generator (SSG) [99].
12. Figure 3.12 Floating overtopping devices. (a) Wave Dragon [52] (www.wavedragon.net) (b) Schematic of the WaveCat concept [100].
13. Figure 3.13 Seabed reacting point absorbers. (a) Archimedes wave swing (AWS) [103] (www.teamwork.nl) (b) Seabased [66] (http://www.seabased.com) (c) BOLT, Norway (Fred Olsen) [104].
14. Figure 3.14 Two-body floating WECs. (a) PowerBuoy [63], USA with kind permission of ocean power technologies, Inc. (b) WaveBob [58] Ireland (en.wikipedia.org/wiki/Wavebob) (c) AquaBuOY [57] (http://nnmrec.oregonstate.edu/finavera-point-absorber).
15. Figure 3.15 Floating multibody heaving WECs. (a) O3 [105] Norway (www.seewec.org) (b) Wavestar [106], Denmark (http://wavestarenergy.com).
16. Figure 3.16 McCabe Wave Pump [56] (http://oceanenergysys.com).
17. Figure 3.17 Oscillating WECs with internal reacting body. (a) Searev (Courtesy of ECN) [107] (b) Penguin [108], Wello (www.wello.eu).
18. Figure 3.18 Pelamis [51].
19. Figure 3.19 M4 [109].
20. Figure 3.20 Flap-type WECs. (a) Oyster [111], UK (b) Waveroller [65], Finland (aw-energy.com/).
Chapter 04
1. Figure 4.1 Tidal range resources around the UK [16].
2. Figure 4.2 Selection of tidal turbines technologies.
3. Figure 4.3 Tidal stream resources around the UK [36].
4. Figure 4.4 Basic definitions of a hydrofoil.
5. Figure 4.5 Profile of a hydrofoil and the resultant, lift and drag forces.
6. Figure 4.6 Example relation between coefficients of lift and drag and angle of attack.
7. Figure 4.7 Turbine characteristics for different size turbines (ϕ = 10–30 m) and different upstream velocities (1–3.08 m s^–1).
8. Figure 4.8 Variation in C_p with number of blades for the Cardiff Tidal Turbine.
9. Figure 4.9 Effects of blade pitch angle on turbine characteristics for the Cardiff Tidal Turbine.
10. Figure 4.10 Rated turbine characteristics.
11. Figure 4.11 Resultant shaft bending moments: (a) with no stanchion; (b) with stanchion upstream; and (c) with stanchion downstream.
12. Figure 4.12 Whirl characteristics of a shaft.
13. Figure 4.13 OpenHydro’s Open Centre Turbine [54].
14. Figure 4.14 CoRMat rotor concept [58].
15. Figure 4.15 Lift and drag diagram for a three-bladed VATT.
16. Figure 4.16 Oxford University’s THAWT
17. Figure 4.17 Deep Green device [75].
18. Figure 4.18 (a) Turbine geometry and (b) example mesh
19. Figure 4.19 Turbine upstream of stanchion.
20. Figure 4.20 Turbine downstream of stanchion.
21. Figure 4.21 Tetrahedral meshed rotating domain and quadrilateral channel mesh with non-conformal interface.
22. Figure 4.22 Velocity attenuation with depth using the 1/7 law.
Chapter 05
1. Figure 5.1 Organisation of IEC.
2. Figure 5.2 Summary of the process for standards-making.
3. Figure 5.3 Organisation of certification activity.
4. Figure 5.4 Outline diagram of a type certification process.
5. Figure 5.5 Project certification outline.
6. Figure 5.6 ‘Bathtub’ curve failure rate behaviour, modelled with Weibull distribution with λ = 1 [8].
7. Figure 5.7 Reliability block diagram of generic floating marine energy converter.
8. Figure 5.8 Example reliability block diagram of four devices in an array.
9. Figure 5.9 Risk priority number colour codes.
10. Figure 5.10 Examples of MRE arrays: (a) Wave Star wave energy converter; (b) Sabella tidal turbine array [30].
11. Figure 5.11 Example WEC devices: (a) BlueTEC floating platform (b) Poseidon Floating Power Plant (c) two Pelamis P2 WECs; (d) CETO 5 and CETO 6 WECs [33].
12. Figure 5.12 Schematic of possible mooring arrangements for a single MRE device: (from left) taut-moored systems with single and multiple lines; basic catenary system; catenary system with auxiliary surface buoy; and lazy wave system with subsea floater and sinker. The combined use of synthetic ropes and chains (dashed and solid lines, respectively) may be feasible.
13. Figure 5.13 FPSO with turret mooring system [35].
14. Figure 5.14 Schematic of proposed array layouts comprising (a) seven and (b) nine buoys with interconnecting lines (grey) and shared connection points (black dots) [39].
15. Figure 5.15 Example design tool applications: (a) an MRE device WAMIT mesh [45]; (b) CFD simulation of a tidal turbine using ANSYS
16. Figure 5.16 Visualisation of a simplified Orcaflex model of the South West Mooring Test Facility.
17. Figure 5.17 Examples of mooring components: (a) Studlink anchor chain (b) Bridon Diamond Blue wire rope (c) Lankhorst TIPTO^®EIGHT 8-strand plaited rope
18. Figure 5.18 Load-extension behaviour of a new nylon mooring rope sample subjected to 10 cycles of bedding-in (tests reported in [50]).
19. Figure 5.19 (a) Atlantis AR-1000 turbine with GBS (b) quadrapod support structure for use with pin piles [55]; (c) schematic of a shallow foundation with shear keys; (d) suction bucket foundation.
20. Figure 5.20 Typical failure modes of offshore piles installed in rock reproduced from [59]: uplift failure of (a) pile and rock mass and (b) grout-to-rock bond; (c) lateral bending failure of rock and pile.
Chapter 06
1. Figure 6.1 Alternative power take-off configurations.
2. Figure 6.2 Alternative electrical power system configurations for variable or fixed speed generators.
3. Figure 6.3 A schematic of a linear electrical generator based on a permanent magnet generator.
4. Figure 6.4 Common types of generators for wave and tidal energy applications: (a) wound rotor induction generator; (b) squirrel cage induction generator; (c) wound rotor synchronous generator; (d) permanent magnet synchronous generator [10].
5. Figure 6.5 MRE device topology type A.
6. Figure 6.6 MRE device topology type B.
7. Figure 6.7 MRE device topology type C.
8. Figure 6.8 MRE device topology type D.
9. Figure 6.9 MRE device topology type E.
10. Figure 6.10 Operating principle of the Wells turbine [14].
11. Figure 6.11 Operating principle of an air impulse turbine [16].
12. Figure 6.12 Performance comparison of Wells and impulse turbines [16].
13. Figure 6.13 Operating principle of the Pelton Wheel.
14. Figure 6.14 Operating principle of the Kaplan turbine.
15. Figure 6.15 Operating principle of the Francis turbine [18].
16. Figure 6.16 Comparison of operating regions for different turbines.
17. Figure 6.17 Example hydraulic circuit.
18. Figure 6.18 Hydraulic circuit symbol key.
19. Figure 6.19 Common pump designs.
20. Figure 6.20 Symbols for pump variants.
21. Figure 6.21 Symbols for motor variants.
22. Figure 6.22 Variable ratio hydrostatic transmission.
23. Figure 6.23 Hydraulic cylinders.
24. Figure 6.24 Detail of typical hydraulic cylinder.
25. Figure 6.25 Rotary vane actuator.
26. Figure 6.26 Simple hydraulic PTO.
27. Figure 6.27 Discrete-level force control PTO.
28. Figure 6.28 Variable displacement pump PTO.
29. Figure 6.29 Manchester Bobber PTO.
30. Figure 6.30 Latching control displacements.
31. Figure 6.31 Pelamis moment control concept.
32. Figure 6.32 Force control by varying motor displacement and generator torque.
33. Figure 6.33 Buoy position, velocity, and flow to high-pressure accumulator for simple hydraulic PTO of Figure 6.26 [33].
34. Figure 6.34 Symbols for different types of converter: (a) the generator-side converter; (b) the grid-side converter or inverter; and (c) the back to back frequency converter and the variable frequency generator.
35. Figure 6.35 Different types of offshore connection hubs, (a) aggregation-only hub; (b) aggregation and transformation hub; and (c) conversion, aggregation and transformation hub, for the two possible configurations with one (left-hand side) and multiple grid-side medium voltage converters (right-hand side).
36. Figure 6.36 Array types for offshore electrical grids: (a) directly connected devices; (b) star cluster array; and (c) radial array.
37. Figure 6.37 Low voltage ride-through test curves for different European countries [44].
Chapter 07
1. Figure 7.1 The Wavestar model at different stages of development. Top left: an early-stage 1 : 40 model being tested in the laboratory (TRL 2). Top right: model with an advanced PTO being tested in the laboratory (TRL 4–5). Bottom left: model of a large single float being tested in the laboratory with real-time control PTO and force measurements on bearings and floater surface (TRL 5). Bottom right: full device model with 38 floats being tested at the Nissum Bredning nursery test centre from 2006 until 2011 (TRL 6).
2. Figure 7.2 Typical pathway of a physical model test.
3. Figure 7.3 Orifice plate used in an OWC model; image shows an orifice plate mounted on the top lid of an OWC model, the wave gauge used to measure the free surface oscillation inside the OWC chamber and the four tubes used to measure the internal air pressure [24].
4. Figure 7.4 Wavestar model using a hydraulic actuator as PTO being tested at the COAST laboratory.
5. Figure 7.5 WaveCat being tested [37, 38].
6. Figure 7.6 WaveCat’s Bilge pump PTO and control system being calibrated [37, 38].
7. Figure 7.7 SQ3 device restrained to heave with linear guide rails in Plymouth University’s COAST laboratory [24].
8. Figure 7.8 Qualysis^® cameras used to track targets attached to a floating body [24].
9. Figure 7.9 Accuracy versus precision.
10. Figure 7.10 Floating WEC model being tested with the bifilar suspension method [24].
11. Figure 7.11 The model inclined at pitch angle θ_S by a mass m_d hung at a distance L_S from the pivot point P (left) and the model being excited in two different modes of motion (pitch and surge) by applying two different angles θ₁ and θ₂ (right).
12. Figure 7.12 Free oscillation test in heave of an OWC buoy scale model.
13. Figure 7.13 Forced oscillation test in heave for an OWC Masuda buoy.
14. Figure 7.14 Variation of the power coefficient (C_P) with tip speed ratio (λ) for different Reynolds numbers for vertical axis turbine tidal model [75].
15. Figure 7.15 Validity of several theories for periodic water waves, according to Le Méhauté [77].
16. Figure 7.16 Three extracts of surface profiles generated for a 1 : 30 scale representation of a three-hour-long sea condition with a once in 100 years return period at Wave Hub. Time series have been shifted so that the largest wave in each profile occurs at time t = 0.
17. Figure 7.17 Time series of focused NewWave at focus location. Focus occurs at time t = 0, with a crest amplitude of 0.3 m. Generated using a Pierson–Moskowitz spectrum with a peak frequency of 0.5 Hz.
18. Figure 7.18 Regular waves power matrix of an OWC Masuda buoy model, 1 : 50 scale [38].
19. Figure 7.19 Regular wave heave RAO (left) and pitch RAO (right) of an OWC Masuda buoy model, 1 : 50 scale [38].
Chapter 08
1. Figure 8.1 Technical aspects of an MRE project [4].
2. Figure 8.2 Typical measurement of the x-component of the velocity in turbulent flows [8].
3. Figure 8.3 Illustration of the domain of influence of the central particle in meshless numerical approaches.
4. Figure 8.4 Hexagonal lattice.
Chapter 09
1. Figure 9.1 Optimum array configuration. G and P stand for the genetic algorithm and parabola intersection method, respectively. The number signifies the objective pursued: (1) to maximise power in an array of real-tuned devices, (2) to maximise power in an array of reactively tuned devices, and (3) to minimise power in an array of reactively tuned devices [14, 16].
2. Figure 9.2 Wave amplitude around a set of (a) one or (b) three heaving cylinders in a nine-body array: (a) the wave amplitude around the white cylinder; (b) the wave amplitude around the three white cylinders in interaction [18].
3. Figure 9.3 Perturbed wave field normalised by recorded undisturbed wave field for the 5 × 5 WEC array configuration [19]. The basin width (X, columns) and length (Y, rows) are expressed in number of WEC unit diameters, D = 0.315 m.
4. Figure 9.4 Calculated disturbance coefficient, K_D, for an aligned (left) and staggered (right) array formed by nine Wave Dragon WECs for irregular long-crested waves [21].
5. Figure 9.5 Calculated disturbance coefficient, K_D, of an array of nine Wave Dragons arranged in two rows with a spacing of (a) D, (b) 2D and (c) 3D, with D = 260 m, for irregular long-crested waves [20].
6. Figure 9.6 Map of the WaveHub area (left) and change in significant wave height in magnitude (a) and percentage (b) along the coastline for varying wave energy transmission percentages under a reference sea state with H_s0 = 3.3 m, T_m = 11 s and direction = N.
7. Figure 9.7 Impacts of a wave farm on the wave conditions with a series of 100 m barriers arranged in a row (left) and two staggered rows of 100 m barriers [23].
8. Figure 9.8 Results along the 25 km grid transect in the lee of the barrier representing the wave farm, at 100 m intervals [23].
9. Figure 9.9 Modification of the significant wave height in the following scenarios: (a) no structure, (b) solid structure and (c) structure with porosity n = 0.7 [24].
10. Figure 9.10 Disturbance coefficient ratio for different porosity values (n) along the line from offshore to the coast crossing device no. 3 [24].
11. Figure 9.11 Values of significant wave height (colour scale) and wave direction in the baseline scenario (a) and for the different wave farm configurations ((b)–(f), for configurations A–E, respectively) under the January offshore wave condition: H_s = 2.9 m, T_e = 11.1 s, direction = NW [25].
12. Figure 9.12 Wave height (left) and variation in the wave height (right) along the 10 m contour for the following scenarios: without (configuration X) and with wave farms (configurations A–E) [25].
13. Figure 9.13 Map of the Costa da Morte, or Death Coast, in NW Spain, with the location of the SIMAR-44 grid node from which offshore wave data were obtained.
14. Figure 9.14 WaveCat schematic (above) [31] and model in the Ocean Basin of the University of Plymouth (below).
15. Figure 9.15 Coarse (left) and fine (right) grids for the SWAN model. For clarity, only one in three and one in nine coordinate lines is shown of the coarse and fine grid, respectively.
16. Figure 9.16 Configurations I (left) and II (right) superimposed on the bathymetry. The 10 m contour and a line at a distance of 3000 m from the wave farm and parallel to it are also delineated for later use.
17. Figure 9.17 Spatial distribution of the undisturbed wave power (baseline) under energetic wave conditions (case study CS 1) as computed with the fine (left) and coarse (right) model grids, with grid spacings of 18 m and 36 m, respectively [7].
18. Figure 9.18 Spatial distribution of wave power in configurations I (above) and II (below), with H_s = 3m, T_e = 10.8 s and direction = NW (case studies CS2 and CS3, respectively) [7].
19. Figure 9.19 Wave farm impact on wave power (ΔJ) and significant wave height (ΔHm₀) along the line passing through the centre of the farm under energetic wave conditions from NW (case studies CS1, CS2 and CS3). Points (1) and (2) denote the position of the first and second row of WECs.
20. Figure 9.20 Wave farm impact on wave power (ΔJ) and significant wave height (ΔHm₀) along a 3000 m distance contour in the lee of the wave farm under energetic wave conditions from NW (case studies CS1, CS2 and CS3). Vertical lines (1) and (4) denote the DAP of the one-row farm, and vertical lines (2) and (3) the DAP of the two-row farm.
21. Figure 9.21 The three wave farm locations considered, at distances to the coast of d = 2 km (CS2, CS6), d = 4 km (CS3, CS7), and d = 6 km (CS4, CS8). The 10 m contour is depicted by a black line, and the Direct nearshore Array Projection (DAP) extends from points P1 to P3.
22. Figure 9.22 Wave power pattern in the baseline scenario (far left) and with the farm located at distances of 6 km (left), 4 km (middle) and 2 km (right) under winter conditions. The wave farm area is delineated by a box [29].
23. Figure 9.23 Variation in wave power (ΔJ) and significant wave height (ΔH_m0) along the centreline of the wave farm (P2*–P2 in Figure 9.21) relative to the values incident on the farm in winter (above – CS2, CS3 and CS4) and summer (below – CS6, CS7 and CS8). For each case the position of the first and second rows of WECs is indicated by markers (1) and (2), respectively.
24. Figure 9.24 NI and significant wave height deficit, ΔH_m0, caused by the wave farm along the 10 m contour in winter (left – CS1, 2, 3, 4) and summer (right – CS5, 6, 7, 8) conditions. NI_max values are depicted by circles.
25. Figure 9.25 RNI in winter, summer and average (of winter and summer) for the three values of farm-to-coast distance. The points where the absolute value of RNI has a local maximum (RNI_max), indicative of maximum impact, are indicated by circles, and the line corresponding to RNI = −5% is also plotted.
26. Figure 9.26 Ratio between local and incoming (target) wave height in presence of the wave farm. The white area represents the emerged beach extension [39].
27. Figure 9.27 Variation of the wave height (left) and the transport flux (right) under the following wave conditions: H_S = 6 m, T_p = 15 s and direction = NW [35].
28. Figure 9.28 Effects of a wave farm consisting of 13 Wave Dragon devices on the wave conditions in Santander Bay, analysed by means of the disturbance coefficient, K_d, for long-crested (above) and short-crested (below) waves [40].
29. Figure 9.29 Wave farm effects on the wave conditions at Santander Bay: a three Wave Dragon wave farm (left) and an eight Blow-Jet wave farm (right). The wave conditions are indicated in the upper line [8].
30. Figure 9.30 Wave height reduction nearshore for Santander Bay under different wave farm configurations [8].
31. Figure 9.31 Location of Perranporth Beach and the Wave Hub in SW England (left; water depths in m), and aerial photo of the beach (right; courtesy of Coastal Channel Observatory).
32. Figure 9.32 Computer-modelled bathymetry at Perranporth Beach, including profiles P1, P2 and P3 (water depth in metres).
33. Figure 9.33 Damage at Perranporth Beach after the storms in winter 2013/2014.
34. Figure 9.34 Boundaries of the computational grids used by the wave propagation and coastal processes models (SWAN and XBeach, respectively; water depths in metres).
35. Figure 9.35 The array of WECs, or wave farm, off Perranporth (water depths in metres).
36. Figure 9.36 Time series of modelled (H_{s, SWAN}) versus observed (H_{s, buoy}) significant wave height.
37. Figure 9.37 Significant wave height in the baseline (H_s, left) and wave farm (H_sf, right) scenarios at the storm peak on 10 March 2008, 1800 UTC. Profiles P1 and P2 are delineated for reference.
38. Figure 9.38 Profiles P1 and P2: initial (1 November 2007, 0000 UTC) and after 3 months (M3) with the wave farm.
39. Figure 9.39 Beach face section of profile P2 at the beginning of the simulated period (1 Nov 2007, 0000 UTC) and after three months (M3) with and without the wave farm [22 Jan 2008, 15:47 UTC].
40. Figure 9.40 BLI values along profiles P1 and P2 at different points in time: 1 month (M1), 3 months (M3) and 6 months (M6) into the study period.
41. Figure 9.41 Bed level impact indicator after the storm, at the end of the study period.
42. Figure 9.42 Beach face eroded area in the baseline (FEA_b) and wave farm (FEA_f) scenarios after the storm.
43. Figure 9.43 Nondimensional erosion reduction on the beach face after the storm.
44. Figure 9.44 The three locations considered for the wave farm, at distances of 2 km, 4 km and 6 km from the reference (10 m water depth) contour.
45. Figure 9.45 Significant wave height (in metres) in the baseline scenario and in the presence of the farm at distances of 2 km, 4 km and 6 km from the reference (10 m water depth) contour in CS1 (clockwise from above left). Line AA′ defines the outer boundary contour for the XBeach coastal processes model.
46. Figure 9.46 Significant wave height (in metres) in the baseline (no farm) scenario (H_s,b) and with the farm at a distance of 2 km (H_s,2km), 4 km (H_s,4km) and 6 km (H_s,6km) from the reference (10 m) contour across the AA′ line in case studies CS1 (top) and CS2 (bottom).
47. Figure 9.47 Bed level impact with the wave farm at a distance of 2 km (BLI_2km), 4 km (BLI_4km) and 6 km (BLI_6km) from the reference contour after the storm in case study CS1.
48. Figure 9.48 Beach face eroded area in the following scenarios: baseline (FEA_b) and with the wave farm at a distance of 2 km (FEA_2km), 4 km (FEA_4km) and 6 km (FEA_6km) at the end of the storm in case studies CS1 (top) and CS2 (bottom). The y-coordinate is the alongshore coordinate, with y increasing towards the north of the beach.
49. Figure 9.49 Non-dimensional erosion reduction on the beach face with the wave farm at distances of 2 km (NER_2km), 4 km (NER_4km) and 6 km (NER_6km) at the end of the storm in case studies CS1 (top) and CS2 (bottom). The y-coordinate is the alongshore coordinate, with y increasing towards the north of the beach.
50. Figure 9.50 Pelagic and benthic division of the oceans.
51. Figure 9.51 Comparison of the global catch data analysed by (a) FAO [72], and (b) recently published research analysis.
52. Figure 9.52 Schematic representation of the EIA methodology.
53. Figure 9.53 Risk analysis process (adapted from Gormley [120]).
54. Figure 9.54 Risk matrix for general risk analysis.
Chapter 11
1. Figure 11.1 Cost breakdown [4–6].
2. Figure 11.2 Rotor costs as a function of diameter.
3. Figure 11.3 LCOE estimates for renewable energy [58].
4. Figure 11.4 R&D efforts in: (a) tidal technology and (b) wave energy types [63].
5. Figure 11.5 Components of social costs.
6. Figure 11.6 Levelised cost of different technologies, including external costs (costs referred to 2006). PWR, pressurised-water reactor; CCGT, combined cycle gas turbine; IGCC, integrated gasification combined cycle; CCS, carbon capture storage.
7. Figure 11.7 Externalities: main valuation techniques [113].
Chapter 12
1. Figure 12.1 Technology Readiness Level and Commercial Readiness Index [1].
2. Figure 12.2 The Alstom concept embodied in the 1MW ReDAPT prototype.
3. Figure 12.3 Path of a successful technology [11].
4. Figure 12.4 Development pedigree of the Alstom Oceade™ tidal turbine.
5. Figure 12.5 Example LCOE contributions for a 10 MW tidal farm.
6. Figure 12.6 Patent filing profile for Alstom Ocean Energy.
7. Figure 12.7 The wave energy converter.
8. Figure 12.8 The Seabased Buoy.
9. Figure 12.9 The linear generator.
10. Figure 12.10 The electrical schedule for the wave power park.
11. Figure 12.11 A schematic illustration of the control system.
12. Figure 12.12 Measurement of the voltage and leakage testing.
13. Figure 12.13 Transfer sequence.
14. Figure 12.14 Deployment of the Seabased device.
15. Figure 12.15 Location map of Lake Sihwa Tidal Power Plant.
16. Figure 12.16 Various tide levels referred to the Incheon mean sea level at Sihwa Dyke.
17. Figure 12.17 Controlled water levels in Lake Sihwa.
18. Figure 12.18 One-way flood generation scheme of Lake Sihwa Tidal Power Plant.
19. Figure 12.19 General layout for construction of Lake Sihwa Tidal Power Plant.
20. Figure 12.20 Construction schedule of Lake Sihwa Tidal Power Plant.
21. Figure 12.21 Powerhouse of Lake Sihwa Tidal Power Plant.
22. Figure 12.22 Sluice of Lake Sihwa Tidal Power Plant.
23. Figure 12.23 Installation of draft tubes of turbine generators in the powerhouses.
24. Figure 12.24 Installation of turbine generators in the powerhouses.
25. Figure 12.25 Aerial view of construction of Lake Sihwa Tidal Power Plant.
26. Figure 12.26 Installed turbine generators just before filling with seawater.
27. Figure 12.27 Aerial view of the Lake Sihwa Tidal Power Plant just after completion.
28. Figure 12.28 Historical water level changes at Lake Sihwa.
29. Figure 12.29 Restored tidal flat after opening of Lake Sihwa Tidal Power Plant.
30. Figure 12.30 Variation of ignition loss in tidal flat sediment before and after the plant opening.
31. Figure 12.31 Orthophoto of Mutriku village.
32. Figure 12.32 Plan of the site layout (kindly supplied by the Basque Energy Agency).
33. Figure 12.33 Final design (kindly supplied by the Basque Energy Agency).
34. Figure 12.34 Wave energy plant under construction (kindly supplied by the Basque Energy Agency).
35. Figure 12.35 Summary of the consenting process in Spain. The coloured rectangles indicate the competent authority for approval or licensing [29].
36. Figure 12.36 Tank testing (kindly supplied by the Basque Energy Agency).
37. Figure 12.37 Breakwater and OWC plant (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
38. Figure 12.38 Thre-dimensional simulation (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
39. Figure 12.39 Cross-section of the OWC plant (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
40. Figure 12.40 Plan of the OWC plant (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
41. Figure 12.41 Storage of precast parts (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
42. Figure 12.42 Positioning of precast parts (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
43. Figure 12.43 Vertical section and breakwater separated (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
44. Figure 12.44 Power plant and breakwater joined together (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
45. Figure 12.45 Columns before closure (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
46. Figure 12.46 Layout of the permanent formwork (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
47. Figure 12.47 Construction of the turbine room (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
48. Figure 12.48 Wave impact during construction of the turbine room (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
49. Figure 12.49 External view of the turbine area, with masonry and impost (kindly supplied by the Directorate of Ports and Maritime Affairs of the Basque government).
50. Figure 12.50 Breakwater and OWC plant, June 2013 (kindly supplied by the Basque Energy Agency).
Chapter 13
1. Figure 13.1 (a) Wave energy maps, identifying technology developers (light grey) and dedicated infrastructure (dark grey) existing in Europe [8].
2. Figure 13.2 Wave and tidal energy research and development facilities accessible through the FP7 MARINET project [33].
3. Figure 13.3 Distribution of wave energy developers in the world [52].
4. Figure 13.4 Wave Dragon in operation.
5. Figure 13.5 Wello’s Penguin WEC in operation at EMEC in Orkney.
6. Figure 13.6 Distribution of tidal energy developers in the world [125].
7. Figure 13.7 Map of the Latin America region (created with Cartopy [252]).
8. Figure 13.8 Point absorber developed by the FURJ at scale 1:10 (from [252]).
9. Figure 13.9 Mexico’s marine energy development potential.
10. Figure 13.10 Point absorber for deployment at El Sauzal, Ensenada. Prototype II, 1 : 4 scale (from [274]).
11. Figure 13.11 Floating pendulum wave energy converter (KRISO, MOF) [297]. (a) artist impression of the device (b) front view of a scale physical model of the device (c) side view of a scale physical model of the device.
12. Figure 13.12 Project allocation.
13. Figure 13.13 Funding allocation.
14. Figure 13.14 Marine trial operation of engineering prototype.
15. Figure 13.15 The duck-shape wave energy converter.
16. Figure 13.16 The 100 kW eagle wave energy converter under working conditions.
17. Figure 13.17 120 kW oscillating buoy wave energy converter.
18. Figure 13.18 Nezha II marine instrument wave energy base station.
19. Figure 13.19 Zhejiang Ocean University wave energy converter.
20. Figure 13.20 Haineng I vertical-axis tidal current energy converter sea trial.
21. Figure 13.21 Haineng I horizontal-axis tidal current energy converter sea trial.
22. Figure 13.22 Horizontal-axis pitch-varying tidal current converter.
23. Figure 13.23 Dalian University of Technology 15 kW tidal turbine.
24. Figure 13.24 Coupled tidal current energy and wave energy system.
25. Figure 13.25 Haiyuan horizontal-axis tidal current energy generation device.
26. Figure 13.26 Sea trial of Haineng II.