How fusion power can save the planet Francis F. Chen

Transcription

1 AN INDISPENSABLE TRUTH How fusion power can save the planet Francis F. Chen

2 TABLE OF CONTENTS * Preface Prologue. Toward a sustainable world i ii PART I WHY FUSION IS INDISPENSABLE Chap. 1. The evidence for climate change 1-1 Is global warming real? 1-1 Physics of temperature change 1-4 Quantifying global warming 1-5 Evidence for climate change 1-6 Paleoclimate 1-6 Computer modeling 1-8 Modern data 1-9 Global temperature rise 1-10 Disasters and catastrophes 1-13 Sea level rise 1-13 The Gulf Stream 1-15 The One Degree effect 1-15 Floods and droughts 1-17 Effect on oceans 1-19 Weather extremes 1-20 Hurricanes and typhoons 1-22 Slowing the inevitable 1-23 Notes, Chap Chap. 2. The future of energy I: Fossil fuels 2-1 Backbone power 2-1 The energy deficit 2-2 Energy units 2-2 Energy consumption 2-2 Energy forecasts 2-5 What drives the increasing demand? 2-5 Where does the energy go? 2-7 Energy reserves 2-9 Coal and carbon management 2-13 Cap and trade 2-14 Carbon sequestration 2-15 Oil and gas pipedreams 2-18 Deep drilling 2-19 Arctic drilling 2-20 * These page numbers are only approximate because of last minute changes and automatic repagination by MS Word and Adobe Acrobat. v

3 Shale oil 2-20 Tar sands 2-21 Oil from algae 2-23 Gas hydrates 2-23 Notes, Chap Chap. 3. The future of energy II: Renewable energy 3-1 Introduction 3-1 Wind energy 3-1 The birds and the bats 3-2 The growth of wind 3-3 When is a megawatt not a megawatt? 3-5 Size matters 3-7 Offshore wind farms 3-9 Blade design 3-10 How turbines work 3-11 The fossil footprint 3-12 Energy storage 3-13 Meshing with the grid 3-14 The bottom line on wind 3-15 Solar energy 3-15 The nature of sunlight 3-15 Ways to use solar power 3-16 Panels on every rooftop 3-18 Photovoltaic panels 3-19 Dangers 3-20 Central station solar power 3-20 Solar thermal plants 3-20 Fossil footprint 3-22 Solar photovoltaic plants 3-23 Storage and transmission 3-24 Is large-scale solar power really feasible? 3-25 How photovoltaics work 3-26 Silicon solar cells 3-29 Thin-film solar cells 3-34 Fossil footprint and environmental issues 3-36 Ideas on the horizon 3-39 Organic solar cells 3-40 Dye-sensitized solar cells 3-41 Quantum-dot solar cells 3-41 Thermoelectric solar energy 3-42 Geo-engineering 3-43 The bottom line on solar 3-44 Energy for transportation 3-49 Hydrogen cars 3-49 A hydrogen economy? 3-49 How to carry hydrogen 3-49 Anatomy of a fuel cell 3-50 vi

4 Sources of hydrogen 3-52 Bottom line on hydrogen cars 3-53 Electric cars and hybrids 3-54 Efficiencies of gas and electric cars 3-54 Gas-electric hybrids 3-55 Plug-in hybrids 3-56 Batteries 3-58 How batteries work 3-59 Supercapacitors and Pseudocapacitors 3-61 Summary of electric cars 3-63 Biofuels 3-63 Nuclear power 3-66 Importance of nuclear power 3-66 How nuclear reactors work 3-66 The cast of characters 3-67 The chain reaction 3-67 Moderation is the key 3-68 Isotope separation 3-68 Inside a nuclear reactor 3-68 Types of reactors 3-69 Liquid-metal fast breeder (LMFBR) 3-69 Reactor control 3-70 Fuel reprocessing 3-70 Radioactive waste storage 3-70 Nuclear proliferation 3-71 Nuclear accidents 3-72 Future reactors 3-72 Fission-fusion hybrids 3-74 Other renewables 3-76 Hydroelectricity 3-76 Geothermal 3-76 Wave and tide energy 3-77 Biomass 3-77 Wild schemes 3-78 Notes on Chap vii

5 PART II HOW FUSION WORKS AND WHAT IT CAN DO Chap. 4. Fusion: energy from seawater 4-1 Fission and fusion: vive la difference! 4-1 Binding energy 4-1 Fission and fusion reactions 4-2 How fusion differs from fission 4-4 The size of energy 4-4 How fusion works 4-5 Plasma: the shining gas 4-6 Designing a magnetic bottle 4-9 What is a magnetic field? 4-9 How can a magnetic field hold a plasma? 4-11 The hole in the doughnut 4-13 Why the field lines have to be twisted 4-14 Mappings, chaos, and magnetic surfaces 4-17 Notes on Chap Chap. 5. Perfecting the magnetic bottle 5-1 Some very large numbers 5-1 Instabilities: the fly in the ointment 5-4 Hot plasma as a superconductor 5-4 How plasma moves in electric fields 5-5 The Rayleigh-Taylor instability 5-6 Stabilization by sheared fields 5-8 Plasma heating and classical leak rates 5-10 Notes on Chap Chap. 6. The remarkable tokamak 6-1 A special kind of torus 6-1 Kink instability and the Kruskal limit 6-2 Mirrors, bananas, and neoclassicism 6-4 Turbulence and Bohm diffusion 6-7 The culprit: microinstabilities 6-10 The drift instability mechanism 6-12 Vertical fields 6-16 Notes on Chap Chap. 7. Evolution and physics of the tokamak 7-1 Magnetic islands 7-1 Sawtooth oscillations 7-4 Diagnostics 7-5 Self-organization 7-6 Magnetic wells and shapely curves 7-6 Evolution of the D-shape 7-8 viii

6 How to heat a plasma to unearthly temperatures 7-10 Mother Nature lends a hand 7-14 Bootstrap current 7-14 The isotope effect 7-16 The Ware pinch 7-16 Zonal flows 7-17 Time scales 7-19 High confinement modes 7-20 The H-mode 7-20 Reverse shear 7-22 Internal transport barriers 7-23 Notes on Chap Chap. 8. A half-century of progress 8-1 What have we accomplished? 8-1 Fits, spurts, and milestones 8-3 Computer simulation 8-8 Unfinished physics 8-11 ELMs 8-11 Fishbones 8-12 Disruptions 8-13 The tokamak s limits 8-17 The Greenwald limit 8-17 Beta and the Troyon limit 8-17 Big Q and little q 8-18 The confinement scaling law 8-19 ITER: Seven nations forge ahead 8-20 Notes on Chap Chap. 9. Engineering: the big challenge 9-1 Introduction 9-1 The first wall and other materials 9-2 The first wall 9-2 The divertor 9-5 Structural materials 9-7 Blankets and tritium breeding 9-8 What is a blanket? 9-8 The role of lithium 9-9 Blanket designs 9-10 Helium Cooled Ceramic Breeder 9-11 Helium-Cooled Lithium-Lead 9-12 Dual-Cooled Lithium Lead 9-13 Maintenance and operation 9-15 Tritium management 9-15 Tritium self-sufficiency 9-15 Tritium basics 9-16 The tritium fuel cycle 9-17 Superconducting magnets 9-18 ix

7 Introduction 9-18 ITER s magnet coils 9-18 The supply of helium 9-20 High-temperature superconductors 9-21 Plasma heating and current drive 9-21 Introduction 9-21 Neutral beam injection 9-21 Ion cyclotron heating 9-21 Electron cyclotron heating 9-22 Lower hybrid heaing 9-23 Remaining physics problems 9-24 Edge Localized Modes 9-24 Disruptions 9-25 Alfvén wave instabilities 9-26 Operating a fusion reactor 9-26 Startup, ramp-down, and steady-state operation 9-26 Maintaining the current profile 9-27 Remote handling 9-27 Fusion development facilities 9-28 IFMIF: International Fusion Materials Irradiation Facility 9-28 Fusion ignition tokamaks 9-29 High Volume Neutron Source 9-29 Fusion Development Facility (FDF) 9-30 A spherical tokamak FDF Fusion power plants 9-31 Commercial feasibility 9-31 Power plant designs 9-32 The cost of electricity 9-36 Methodology 9-36 Important dependences 9-37 Cost levelization / discounting 9-38 The cost of fusion energy Notes on Chap Chap. 10. Fusion concepts for the future 10-1 Advanced fuel cycles 10-1 Stellarators 10-3 Wendelstein 10-4 Large Helical Device 10-5 Benefits of non-axisymmetry 10-6 Compact stellarators 10-7 Spherical toruses 10-8 Spherical tokamaks 10-8 Spheromaks Magnetic mirrors How mirrors work Ioffe bars and baseball coils Mirror machines Axisymmetric mirrors x

8 Direct conversion Magnetic pinches Reversed-field pinch Field-reversed configuration Z-pinches Plasma focus Inertial confinement fusion Introduction General principles Instabilities Glass lasers Other lasers Target designs Direct and indirect drive Reactor technology Pulsed power Hoaxes and dead ends Cold fusion Bubble fusion Muon fusion Astron Electrostatic confinement Migma Ultimate fusion Notes on Chap Chap. 11. Conclusions 11-1 Scientific summary 11-1 Cost of developing fusion 11-1 Conclusion 11-4 Epilogue 11-4 Notes on Chap xi