Electricity from Wave and Tide

PAUL A. LYNN obtained his B.Sc.(Eng) and Ph.D. degrees from Imperial College London, UK. After several years in the electrical/electronics industry, he lectured at Imperial College and the University of Bristol. As a retired academic, Dr. Lynn's long-term interest in renewable energy has led to a trilogy of Wiley books (including this one), and three solar-powered boats. He is the author of ten other books and numerous technical papers and articles.

• Preface ix Acknowledgements xi1. Introduction 11.1 Marine energy and Planet Earth 11.2 Marine resources 51.2.1 Waves of the world 51.2.2 Tides of the world 111.3 A piece of history 181.3.1 Working with waves 181.3.2 Tapping tides 231.4 Power, energy and performance 271.5 Into the future 34References 372. Capturing marine energy 392.1 Ocean waves 392.1.1 Linear waves 392.1.2 Random waves 432.1.3 Wave spectra482.1.4 Wave modification 522.1.5 Wave measurement 562.2 Wave energy conversion 592.2.1 Introductory 592.2.2 Types of wave energy converter 602.2.3 Principles of wave energy capture 622.2.3.1 Floating devices 622.2.3.2 Tuning and damping 642.2.3.3 When waves meet WECs 682.3 Tidal streams 712.3.1 Hydrodynamics 712.3.2 Tidal harmonics 762.3.3 Predicting tidal streams 832.4 Tidal stream energy conversion 862.4.1 Introductory 862.4.2 Tidal stream turbines 892.4.2.1 Turbine sizes and power ratings 892.4.2.2 Extracting energy: the Betz Limit 932.4.2.3 Lift and drag 962.4.2.4 Rotor speed and power coefficient 1022.4.3 Turbine siting 1052.5 Research and development 1082.5.1 Models and test tanks 1082.5.2 The European Marine Energy Centre (EMEC) 1112.5.2.1 Wave and tidal test sites 1112.5.2.2 Research activities 121References 1243. Generating electricity 1253.1 Introductory 1253.2 Power take-off 1263.3 AC electricity 1303.4 Generators 1413.4.1 Introductory 1413.4.2 Synchronous generators 1473.4.3 Asynchronous generators 1513.4.3.1 Squirrel-cage and wound-rotor induction machines 1513.4.3.2 Doubly-fed induction generators 1573.4.4 Linear motion generators 1623.5 Connecting to the grid 1663.5.1 Setting the scene 1663.5.2 Grid strength and fault levels 1693.5.3 Electrical quality 1733.6 Large-scale renewable energy 1753.6.1 Introductory 1753.6.2 Intermittency and variability1763.6.3 Capacity credit and backup generation 179References 1834. Case studies: Wave energy converters 1854.1 Introductory 1854.2 Case studies 1864.2.1 Pelamis  1864.2.2 Oyster 1924.2.3 Limpet andMutriku 1994.2.4 Wave Dragon 2054.2.5 PowerBuoy® 2114.2.6 Penguin 216References 2215. Case studies: Tidal stream energy converters 2235.1 Introductory 2235.2 Case studies 2245.2.1 Andritz Hydro Hammerfest 2245.2.2 Atlantis Resources 2295.2.3 Marine Current Turbines 2345.2.4 OpenHydro 2405.2.5 Pulse Tidal 2455.2.6 Scotrenewables Tidal Power 2515.2.7 Tidal Generation 258References 262Index 263

“This thoroughly readable and attractively illustrated volume certainly deserves a place on many a bookshelf.”  (Underwater Technology, 1 March 2014)“With 165 full-colour illustrations and photographs of devices at an advanced stage, this book is both a valuable primer on marine energy and an inspiring picture of today’s most promising marine energy devices and developments.”  (Real Power magazine, 1 October 2013)