Page 7 - Applied Photovoltaics

2.1.1 The bond model 32
2.1.2 The band model 33
2.1.3 Doping 33
2.2 Semiconductor types 34
2.2.1 Crystalline silicon 34
2.2.2 Multicrystalline silicon 34
2.2.3 Amorphous silicon 35
2.2.4 Thin film crystalline silicon 36
2.3 Absorption of light 36
2.4 Recombination 37
2.5 p-n junctions 38

Chapter 3— THE BEHAVIOUR OF SOLAR CELLS 43
3.1 Effect of light 43
3.2 Spectral response 47
3.3 Effect of temperature 49
3.4 Effect of parasitic resistances 51

Chapter 4— CELL PROPERTIES AND DESIGN 57
4.1 Efficiencies 57
4.2 Optical losses 58
4.3 Recombination losses 62
4.4 Top contact design 63
4.4.1 Bulk and sheet resistivities 63
4.4.2 Grid spacings 65
4.4.3 Other losses 67
4.5 Laboratory cells versus industry requirements 69
4.6 The Laser Grooved, Buried Contact Solar Cell 70

Chapter 5— PV CELL INTERCONNECTION AND MODULE FABRICATION75
5.1 Module and circuit design 75
5.2 Identical cells 75
5.3 Non-identical cells 76
5.4 Non-identical modules 76
5.5 Hot-spot heating 79
5.6 Module structure 83
5.7 Environmental protection 84
5.8 Thermal considerations 85
5.9 Electrical insulation 88
5.10 Mechanical protection 89
5.11 Degradation and failure modes 89

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