InhaltsangabePreface xi Abbreviations xiii 1 Introduction 1 1.1 Introduction 1 1.1.1 Why Photovoltaics? 1 1.1.2 Who Should Read this Book? 2 1.1.3 Structure of the Book 2 1.2 What is Energy? 3 1.2.1 Definition of Energy 3 1.2.2 Units of Energy 4 1.2.3 Primary, Secondary and End Energy 5 1.2.4 Energy Content of Various Substances 6 1.3 Problems with Today's Energy Supply 7 1.3.1 Growing Energy Requirements 7 1.3.2 Tightening of Resources 8 1.3.3 Climate Change 9 1.3.4 Hazards and Disposal 10 1.4 Renewable Energies 11 1.4.1 The Family of Renewable Energies 11 1.4.2 Advantages and Disadvantages of Renewable Energies 12 1.5 Photovoltaic - The Most Important in Brief 12 1.5.1 What Does "Photovoltaic" Mean? 13 1.5.2 What are Solar Cells and Solar Modules? 13 1.5.3 How is a Typical Photovoltaic Plant Structured? 14 1.5.4 What Does a Photovoltaic Plant "Bring?" 14 1.6 History of Photovoltaics 15 1.6.1 How it all Began 15 1.6.2 The First Real Solar Cells 16 1.6.3 From Space to Earth 18 1.6.4 From Toy to Energy Source 18 2 Solar Radiation 21 2.1 Properties of Solar Radiation 21 2.1.1 Solar Constant 21 2.1.2 Spectrum of the Sun 22 2.1.3 Air Mass 23 2.2 Global Radiation 24 2.2.1 Origin of Global Radiation 24 2.2.2 Contributions of Diffuse and Direct Radiation 25 2.2.3 Global Radiation Maps 25 2.3 Calculation of the Position of the Sun 29 2.3.1 Declination of the Sun 29 2.3.2 Calculating the Path of the Sun 31 2.4 Radiation on Tilted Surfaces 33 2.4.1 Radiation Calculation with the Three-Component Model 33 2.4.2 Radiation Estimates with Diagrams and Tables 37 2.4.3 Yield Gain through Tracking 38 2.5 Radiation Availability and World Energy Consumption 40 2.5.1 The Solar Radiation Energy Cube 40 2.5.2 The Sahara Miracle 41 3 Fundamentals of Semiconductor Physics 43 3.1 Structure of Semiconductors 43 3.1.1 Bohr's Atomic Model 43 3.1.2 Periodic Table of the Elements 45 3.1.3 Structure of the Silicon Crystal 46 3.1.4 Compound Semiconductors 47 3.2 Band Model of the Semiconductor 47 3.2.1 Origin of Energy Bands 47 3.2.2 Differences in Isolators, Semiconductors and Conductors 48 3.2.3 Intrinsic Carrier Concentration 49 3.3 Charge Transport in Semiconductors 50 3.3.1 Field Currents 50 3.3.2 Diffusion Currents 52 3.4 Doping of Semiconductors 53 3.4.1 nDoping 53 3.4.2 pDoping 54 3.5 The pn Junction 54 3.5.1 Principle of Method of Operation 55 3.5.2 Band Diagram of the p-n Junction 56 3.5.3 Behavior with Applied Voltage 58 3.5.4 Diode Characteristics 59 3.6 Interaction of Light and Semiconductors 60 3.6.1 Phenomenon of Light Absorption 60 3.6.2 Light Reflection on Surfaces 64 4 Structure and Method of Operation of Solar Cells 67 4.1 Consideration of the Photodiode 67 4.1.1 Structure and Characteristics 67 4.1.2 Equivalent Circuit 69 4.2 Method of Function of the Solar Cell 69 4.2.1 Principle of the Structure 69 4.2.2 Recombination and Diffusion Length 70 4.2.3 What Happens in the Individual Cell Regions? 71 4.2.4 BackSurface Field 73 4.3 Photocurrent 73 4.3.1 Absorption Efficiency 74 4.3.2 Quantum Efficiency 75 4.3.3 Spectral Sensitivity 76 4.4 Characteristic Curve and Characteristic Dimensions 77 4.4.1 Short Circuit Current ISC 78 4.4.2 Open Circuit Voltage VOC 78 4.4.3 Maximum Power Point (MPP) 79 4.4.4 Fill Factor FF 79 4.4.5 Efficiency h 80 4.4.6 Temperature Dependency of Solar Cells 80 4.5 Electrical Description of Real Solar Cells 82 4.5.1 Simplified Model 82 4.5.2 Standard Model (Single-Diode Model) 83 4.5.3 TwoDiode Model 83 4.5.4 Determining the Parameters of the Equivalent Circuit 85 4.6 Considering Efficiency 87 4.6.1 Spectral Efficiency 87 4.6.2 Theoretical Efficiency 90 4.6.3 Losses in Real Solar Cells 92 4.7 High Efficiency Cells 95 4.7.1 Bu

InhaltsangabePreface xi Abbreviations xiii 1 Introduction 1 1.1 Introduction 1 1.1.1 Why Photovoltaics? 1 1.1.2 Who Should Read this Book? 2 1.1.3 Structure of the Book 2 1.2 What is Energy? 3 1.2.1 Definition of Energy 3 1.2.2 Units of Energy 4 1.2.3 Primary, Secondary and End Energy 5 1.2.4 Energy Content of Various Substances 6 1.3 Problems with Today's Energy Supply 7 1.3.1 Growing Energy Requirements 7 1.3.2 Tightening of Resources 8 1.3.3 Climate Change 9 1.3.4 Hazards and Disposal 10 1.4 Renewable Energies 11 1.4.1 The Family of Renewable Energies 11 1.4.2 Advantages and Disadvantages of Renewable Energies 12 1.5 Photovoltaic - The Most Important in Brief 12 1.5.1 What Does "Photovoltaic" Mean? 13 1.5.2 What are Solar Cells and Solar Modules? 13 1.5.3 How is a Typical Photovoltaic Plant Structured? 14 1.5.4 What Does a Photovoltaic Plant "Bring?" 14 1.6 History of Photovoltaics 15 1.6.1 How it all Began 15 1.6.2 The First Real Solar Cells 16 1.6.3 From Space to Earth 18 1.6.4 From Toy to Energy Source 18 2 Solar Radiation 21 2.1 Properties of Solar Radiation 21 2.1.1 Solar Constant 21 2.1.2 Spectrum of the Sun 22 2.1.3 Air Mass 23 2.2 Global Radiation 24 2.2.1 Origin of Global Radiation 24 2.2.2 Contributions of Diffuse and Direct Radiation 25 2.2.3 Global Radiation Maps 25 2.3 Calculation of the Position of the Sun 29 2.3.1 Declination of the Sun 29 2.3.2 Calculating the Path of the Sun 31 2.4 Radiation on Tilted Surfaces 33 2.4.1 Radiation Calculation with the Three-Component Model 33 2.4.2 Radiation Estimates with Diagrams and Tables 37 2.4.3 Yield Gain through Tracking 38 2.5 Radiation Availability and World Energy Consumption 40 2.5.1 The Solar Radiation Energy Cube 40 2.5.2 The Sahara Miracle 41 3 Fundamentals of Semiconductor Physics 43 3.1 Structure of Semiconductors 43 3.1.1 Bohr's Atomic Model 43 3.1.2 Periodic Table of the Elements 45 3.1.3 Structure of the Silicon Crystal 46 3.1.4 Compound Semiconductors 47 3.2 Band Model of the Semiconductor 47 3.2.1 Origin of Energy Bands 47 3.2.2 Differences in Isolators, Semiconductors and Conductors 48 3.2.3 Intrinsic Carrier Concentration 49 3.3 Charge Transport in Semiconductors 50 3.3.1 Field Currents 50 3.3.2 Diffusion Currents 52 3.4 Doping of Semiconductors 53 3.4.1 nDoping 53 3.4.2 pDoping 54 3.5 The pn Junction 54 3.5.1 Principle of Method of Operation 55 3.5.2 Band Diagram of the p-n Junction 56 3.5.3 Behavior with Applied Voltage 58 3.5.4 Diode Characteristics 59 3.6 Interaction of Light and Semiconductors 60 3.6.1 Phenomenon of Light Absorption 60 3.6.2 Light Reflection on Surfaces 64 4 Structure and Method of Operation of Solar Cells 67 4.1 Consideration of the Photodiode 67 4.1.1 Structure and Characteristics 67 4.1.2 Equivalent Circuit 69 4.2 Method of Function of the Solar Cell 69 4.2.1 Principle of the Structure 69 4.2.2 Recombination and Diffusion Length 70 4.2.3 What Happens in the Individual Cell Regions? 71 4.2.4 BackSurface Field 73 4.3 Photocurrent 73 4.3.1 Absorption Efficiency 74 4.3.2 Quantum Efficiency 75 4.3.3 Spectral Sensitivity 76 4.4 Characteristic Curve and Characteristic Dimensions 77 4.4.1 Short Circuit Current ISC 78 4.4.2 Open Circuit Voltage VOC 78 4.4.3 Maximum Power Point (MPP) 79 4.4.4 Fill Factor FF 79 4.4.5 Efficiency h 80 4.4.6 Temperature Dependency of Solar Cells 80 4.5 Electrical Description of Real Solar Cells 82 4.5.1 Simplified Model 82 4.5.2 Standard Model (Single-Diode Model) 83 4.5.3 TwoDiode Model 83 4.5.4 Determining the Parameters of the Equivalent Circuit 85 4.6 Considering Efficiency 87 4.6.1 Spectral Efficiency 87 4.6.2 Theoretical Efficiency 90 4.6.3 Losses in Real Solar Cells 92 4.7 High Efficiency Cells 95 4.7.1 Bu Leseprobe