Third Generation Photovoltaics (eBook)

Preface 7
Table of Contents 9
1 Introduction 12
1.1 “Twenty-Twenty Vision” 12
1.2 The Three Generations 12
1.3 Outline of Options 15
Exercise 16
References 16
2 Black-Bodies, White Suns 18
2.1 Introduction 18
2.2 Black-Body Radiation 18
2.3 Black-Body in a Cavity 21
2.4 Angular Dependence of Emitted Radiation 22
2.5 Direct and Diffuse Efficiencies 26
2.6 Black-Body Emission Properties 27
Exercise 30
References 30
3 Energy, Entropy and Efficiency 32
3.1 Introduction 32
3.2 Energy and Entropy Conservation 32
3.3 Carnot Efficiency 33
3.4 Landsberg Limit 35
3.5 Black-Body Limit 36
3.6 Multi-Colour Limit 38
3.7 Non-Reciprocal Systems 40
3.8 Ultimate System 41
3.9 Omnidirectional Global Converters 42
3.10 Summary 43
Exercise 44
References 44
4 Single Junction Cells 46
4.1 Efficiency Losses 46
4.2 Shockley-Queisser Formulation 49
4.3 Hot Photons ( Chemical Potential of Light) 51
4.4 Einstein Coefficients 54
4.5 Photon Boltzmann Equation 56
4.6 General Cell Analysis 60
4.7 Lasing Conditions 61
4.8 Photon Spatial Distributions 62
4.9 Effect of Sample Thickness 65
4.10 Thermodynamics of Single Junction Cell 66
Exercises 68
References 68
5 Tandem Cells 70
5.1 Spectrum Splitting and Stacking 70
5.2 Split-Spectrum Cells 71
5.3 Stacked Cells 72
5.4 Two Terminal Operation 74
5.5 Infinite Number of Cells 75
5.6 Approximate Solution 76
5.7 Thermodynamics of the Infinite Stack 77
Exercises 77
References 77
6 Hot Carrier Cells 80
6.1 Introduction 80
6.2 Relevant Time Constants 80
6.3 Ross And Nozik’s Analysis 83
6.4 Simplification for Eg = 0 88
6.5 Würfel’s Analysis 88
6.6 Possible Low Dimensional Implementation 90
Exercise 91
References 91
7 Multiple Electron-Hole Pairs per Photon 92
7.1 Introduction 92
7.2 Multiple-Carrier Photon Emission 93
7.3 Limiting Performance 94
7.4 Comparison with Würfel’s Analysis 96
7.5 Possible Implementation 97
7.6 Generalised Analysis 97
7.7 Raman Luminescence 99
Exercises 103
References 103
8 Impurity Photovoltaic and Multiband Cells 106
8.1 Introduction 106
8.2 3-Band Cell 108
8.3 Photon Absorption Selectivity 109
8.4 Absorption Leakage Loss 113
8.5 Other Possible Multigap Schemes 115
8.6 Impurity Photovoltaic Effect 117
8.7 Up-and Down-Conversion 118
Exercises 118
References 119
9 Thermophotovoltaic and Thermophotonic Conversion 122
9.1 Introduction 122
9.2 Solar Thermal Conversion 124
9.3 Thermophotovoltaic Conversion 125
9.4 Thermophotonics 129
Exercises 133
References 133
10 Conclusions 136
References 137
Appendix A 139
Greek Alphabet 139
Appendix B 141
Physical Constants 141
Appendix C 142
Fermi-Dirac and Bose-Einstein Integrals 142
C.1 Functional Expressions 142
C.2 General Properties 143
C.3 Special Cases 143
C.4 Approximate Expressions 144
C.5 More General Integrals 145
References 147
Appendix D 148
List Of Symbols 148
Appendix E 150
Quasi-Fermi Levels 150
E.1 Introduction 150
E.2 Thermal Equilibrium 150
E.3 Non-Equilibrium 151
E.4 Interfaces 152
E.5 Non-Equilibrium P-N Junction 153
E.6 Use Of Quasi-Fermi Levels 154
Appendix F 158
Solutions to Selected Problems 158
Exercise 2.1 158
Exercise 3.1 159
Exercise 4.1 160
Exercise 4.3 161
Exercise 5.1 164
Exercise 5.2 165
Exercise 6.1 165
Exercise 7.1 166
Exercise 8.1 167
References 168
Index 170