Contents
List of figures, tables and boxes xi
Preface xxxi
Online supplemental material xxxiii
Acknowledgements xxxv
Chapter highlights xxxvii
List of abbreviations xlv
Chapter 1 Introduction and Key Points from Volume 1 1
1.1 The scientific basis for concern about global warming 1
1.2 Kaya identity and efficiency versus C-free energy tradeoffs 2
1.3 Potential reductions inend-use energy demand 5
Chapter 2 Solar Energy 9
2.1 Seasonal, latitudinal and diurnal distribution of solar energy 10
2.2 Photovoltaic electricity 17
2.3 Solar thermal generation of electricity 55
2.4 Solar thermal energy for heating and hot water 66
2.5 Solar thermal energy for air conditioning 77
2.6 Solar cogeneration: Integrated PV modules and thermal collectors 82
2.7 Industrial uses of solar thermal energy 84
2.8 Direct use of solar energy for desalination, in agriculture and for cooking 86
2.9 Dealing with the intermittent nature of solar energy 88
2.10 Synthesis and global potential 91
Chapter 3 Wind Energy 95
3.1 Introduction 95
3.2 Components and characteristics of wind turbines 95
3.3 Wind turbine aerodynamics 101
3.4 Wind turbine generators 105
3.5 Variation of wind speed and turbulence with height near the earth’s surface 107
3.6 Power output from a wind turbine 108
3.7 Available wind resources 114
3.8 Wind farms 116
3.9 Scaling relationships and implications for required land area 117
3.10 Offshore wind power 121
3.11 Mitigating the adverse effect of fluctuations in available wind energy 129
3.12 Long-distance transmission 138
3.13 Economics 140
3.14 Baseload wind-derived electricity: Strategies and costs 154
3.15 Energy payback time and GHG emissions 161
3.16 Noise and impact on birds 164
3.17 Benefits to farmers 164
3.18 Overcoming local opposition 164
3.19 Global and regional wind energy potential and cost 165
3.20 Scenario of future wind energy use 169
3.21 Summary 170
Chapter 4 Biomass Energy 173
4.1 Introduction 173
4.2 Sources of biomass for energy 175
4.3 Processes for extracting energy from biomass 184
4.4 Electricity from biomass 201
4.5 Environmental and social considerations in the use of biomass for energy 206
4.6 Net energy yield and GHG balance of biomass energy 223
4.7 Biomass as a chemical feedstock 244
4.8 Comparison of CO2 emission savings for alternative uses of land 249
4.9 Global biomass energy potential 256
4.10 Cost of biomass and biomass products 266
4.11 Vulnerability of biomass energy production to climatic change 273
4.12 Summary and synthesis 273
Chapter 5 Geothermal Energy 279
5.1 Introduction 279
5.2 Geothermal resources 279
5.3 Technologies for utilizing geothermal energy 281
5.4 Environmental considerations 288
5.5 Current and potential utilization and costs 289
5.6 Concluding comments 295
Chapter 6 Hydroelectric Power 297
6.1 Physical principles 297
6.2 Hydroelectric configurations and types of runners 298
6.3 Existing hydroelectric capacity and electricity generation 300
6.4 Technical and economic potential for further hydropower 301
6.5 Upgrading existing facilities 305
6.6 Social and environmental considerations 306
6.7 GHG emissions 306
6.8 Cost 309
6.9 Concluding comments 310
Chapter 7 Ocean Energy 311
7.1 Introduction 311
7.2 Wave energy 311
7.3 Tidal energy 313
7.4 Tidal currents and other marine currents 319
7.5 Ocean thermal energy conversion 320
viii CARBON-FREE ENERGY SUPPLY
7.6 Energy from oceansalinity gradients 323
7.7 Resource potential 323
7.8 Concluding comments 324
Chapter 8 Nuclear Energy 325
8.1 Introduction 325
8.2 Basics of nuclear energy physics 325
8.3 Nuclear powerplant reactor technologies 336
8.4 The nuclear fuel chain 341
8.5 Safety 355
8.6 Nuclear weapons, arms proliferation and terrorism risks 356
8.7 Cost 360
8.8 Lifecycle energy balance and GHG emissions from nuclear powerplants 366
8.9 Operational Constraints 378
8.10 Current nuclear capacity 379
8.11 Potential contribution of nuclear energy to future world energy needs 380
8.12 Concluding comments 386
Chapter 9 Carbon Capture and Storage 389
9.1 Introduction 389
9.2 Sources of CO2 for capture and storage 389
9.3 Capture of CO2 391
9.4 Compression or liquefaction and transport 407
9.5 Compounded energy penalties for production of electricityand hydrogen 408
9.6 Methods for and costs of long-term storage of CO2 409
9.7 Environmental and safety issues 414
9.8 Regional and global storage potential 422
9.9 Current status and scenarios 423
9.10 Summary 424
Chapter 10 The Hydrogen Economy 427
10.1 Introduction 427
10.2 Properties of hydrogen as an energy carrier 427
10.3 Production of hydrogen 429
10.4 Storage of hydrogen 439
10.5 Transmission of hydrogen 442
10.6 End-use applications of hydrogen 445
10.7 Costs 451
10.8 Safety and environmental considerations 455
10.9 Scenarios 458
10.10 Summary and synthesis 461
Chapter 11 Community-Integrated Energy Systems with Renewable Energy 463
11.1 Introduction 463
11.2 Seasonal underground storage of thermal energy 463
CONTENTS ix
11.3 Utilization of renewable energy with district energy systems 466
11.4 Summary 470
Chapter 12 Integrated Scenarios for the Future 473
12.1 Summary of the characteristics of C-free energy sources 473
12.2 Summary of recently published low-emission scenarios 480
12.3 Construction of C-free energy supply scenarios 484
12.4 Impact on climate and ocean acidification 506
12.5 A role for carbon sequestration 513
12.6 Summary 515
Chapter 13 Policy Sketch and Concluding Thoughts 519
13.1 Promoting C-free energy 520
13.2 Research and development 551
13.3 Preserving forests and enhancing carbon sinks 522
13.4 Geo-engineering? 523
13.5 Concluding thoughts 523
Appendix A Prefixes and Conversion Factors 527
Appendix B Computing the Embodied Energy of Manufactured Materials 528
Appendix C Financial Parameters 530
Appendix D Heating Values of Fuels and Energy Equivalents 532
Appendix E Websites with More Information 533
Appendix F Software Tools for the Analysis of Renewable Energy 535
References 537
Index 567