Contents More Information

Cambridge University Press 978-0-521-74763-9 - Wind Power Peter Musgrove Table of Contents More information

Contents

Preface page xiii Acknowledgements xiv

1 Wind power and our energy needs: an overview 1 Traditional windmills 1 Power and energy in the modern world 2 Global warming and climate change 3 Renewable energy sources 6 Wind energy conversion 7 Energy payback and wind energy costs 8 Intermittency issues 9 Wind or nuclear? 9 Costs compared with conventional generation 10 Wind power’s growth and potential 11 2 The ﬁrst windmills 15 Hero’s toy windmill 15 Early Persian drag-driven windmills 15 Chinese drag-driven windmills 19 The European windmill 20 How post mills work 21 Origins and economics 22 3 Seven centuries of service 27 Post mills 27 Diffusion through Europe 27 Medieval milling capacity 28 Controlling the mill 29 Sail developments 30

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Milling the grain 33 Design evolution 35 Smock mills and tower mills 37 Control refinements 40 The power output from traditional windmills 41 Land drainage and other applications 46 The windmill’s nineteenth-century peak 47 Causes of decline 48 Steam power 48 White bread 49 Roller mills 51 The American multi-bladed windpump 52 4 Generating electricity: the experimental years, 1887 to 1973 57 The first wind-powered electricity generation 58 Danish beginnings: Poul la Cour 63 The inter-war years 65 Small wind-electric systems 68 Grandpa’s Knob, Vermont: the first megawatt-plus machine 70 Wartime shortages rekindle Danish interest 73 Post-war energy concerns, and Denmark’s Gedser mill 75 French and German post-war programmes 79 The UK post-war programme 81 5 The evolution of the modern wind turbine, 1973 to 1990 87 The 1973 oil crisis 87 The American Federal wind power program 89 First generation machines, Mod-0 and Mod-1 89 Second- and third-generation machines, Mod-2 and Mod-5 92 The American/Swedish WTS-4 94 The Darrieus vertical-axis wind turbine 95 European national wind power programmes 99 Sweden 99 Germany 101 Denmark 102 A different Danish way forward 105 The Tvind machine 105 Small grid-connected wind turbines 106 The Californian wind boom 112 The first wind farms 113 Danish imports 115

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The market peaks 118 Environmental concerns 119 Design evolution 120 Danish success factors 123 6 Progress and economics in Europe, 1973 to 1990 125 Denmark 125 Stall control or pitch control? 126 Shut-down in high wind speeds 128 Costs relative to the annual energy output 129 Costs per unit energy output 131 Cost comparisons 132 The Netherlands and Germany 133 7 UK progress, 1973 to 1990 137 Wind power: the least promising renewables option? 137 The offshore wind potential 138 Managing wind power’s variability 140 The Department of Energy wind programme 142 The Orkney multi-megawatt wind turbine 142 Offshore wind farm assessment 143 Vertical-axis wind turbines 145 Other UK wind turbine developments 149 Lawson-Tancred 149 Fair Isle 150 Carmarthen Bay wind turbine test centre 151 Howden 151 Wind Energy Group 153 Institutional barriers 153 Privatisation and the Non-Fossil Fuel Obligation (NFFO) 155 8 Development and deployment, 1990 to 2008 159 Global overview 159 Denmark 162 The 1990s, a decade of growth 162 Offshore wind makes progress 165 Danish overview 169 Germany 171 1991: a feed-in tariff established 171 Domestic manufacture 172 From 2000: the Renewable Energy Law 174 German overview 176

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Spain 178 The 1994 feed-in tariff 178 Spanish overview 180 United Kingdom 181 The disappointing 1990s 181 Why NFFO failed 185 The Renewables Obligation 187 Offshore wind farms 189 UK overview 193 United States 194 Low growth beginnings 194 The Production Tax Credit (PTC) and ‘green power’ 195 Momentum builds 197 US overview 199 Canada, Netherlands and Japan 202 India 203 China 205 9 The future: from marginal to mainstream 209 Low-carbon options for electricity generation 210 Carbon capture and storage 210 Nuclear power 211 Renewables 212 Wind power’s progress 214 Cost-of-energy comparisons 216 Variability: keeping the lights on 219 Wind power’s global growth 221

Appendix A The power output from wind turbines 227 The Betz limit 229 How many blades? The effect of solidity 229 Efﬁciency 231 Rotor drag 231 Appendix B The performance of traditional windmills 233 The power required to grind wheat 233 Smeaton’s 1759 measurements using model windmills 234 Coulomb’s 1781 measurements on working windmills 236 Dutch measurements on windmills in the 1920s and 1930s 239 Smeaton’s anomalous results 241 The power available from traditional windmills 243 Comparison with drag-driven Persian windmills 245

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Appendix C Wind characteristics 247 Wind speed variation with height 247 Wind speed distribution 247 Notes 250 References 306 Index 320