Preface 000 1. Introduction 1 Monika Freunek (Müller) References 5 2. Fundamental Limits of Solar Energy Conversion 7 Thorsten Trupke and Peter Würfel 2.1. Introduction 2.2. The Carnot Efficiency - A Realistic Limit for PV Conversion? 2.3.

Solar Cell Absorbers - Converting Heat into Chemical 2.4. No Junction Required - The IV Curve of a Uniform Absorber 2.5. Limiting Efficiency Calculations 2.6. Real Solar Cell Structures 2.7.

Beyond the Shockley Queisser Limit 2.8. Summary and Conclusions Acknowledgement References 3. Optical Modeling of Photovoltaic Modules Carsten Schinke, Malte R.Vogt, and Karsten Bothe 3.1. Introduction 3.1.

1. Terminology 3.1.2. Simulation object 3.1.3. Photon (Light ray) 3.

1.4. Light source 3.1.5. Simulation domain 3.1.6.

Simulation scene 3.1.7. Photon marker 3.1.8. Surface effects with Ray Tracing Simulations 27 3.1.

9. Boundary conditions 32 3.1.10. Photon shifters 32 3.2. Basics of Optical Ray Tracing Simulations 32 3.2.

1. Ray Optics 32 3.2.1.1. Basic Assumptions 33 3.2.1.

2. Absorption of Light 33 3.2.1.3. Refraction of Light at Interfaces 34 3.2.1.

4. Modeling of Thin Films 35 3.2.2. Ray Tracing 37 3.2.3. Monte-Carlo Particle Tracing 38 3.

2.4. Statistical Uncertainty of Monte-Carlo Results 40 3.2.5. Generating Random Numbers with Non-Uniform Distributions 42 3.3. Modeling Illumination 46 3.

3.1. Basic Light Sources 46 3.3.2. Modeling Realistic Illumination Conditions 48 3.3.2.

1. Preprocessing of Irradiance Data 49 3.3.2.2. Implementation for Ray Tracing 50 3.3.2.

3. Application Example 52 3.4. Specific Issues for Ray Tracing of Photovoltaic Modules 53 3.4.1. Geometries and Symmetries in PV Devices 55 3.4.

2. Multi-Domain Approach 57 3.4.2.1. Module domain 59 3.4.2.

2. Front Finger Domain 60 3.4.2.3. Front Texture Domain 60 3.4.2.

4. Rear Side Domains 61 3.4.3. Post processing of Simulation Results 61 3.4.4. Ray Tracing Application Examples 64 3.

4.4.1. Validation of Simulation Results 64 3.4.4.2. Optical Loss Analysis: From Cell to Module 66 3.

4.4.3. Bifacial Solar Cells and Modules 68 3.5. From Optics to Power Output 69 3.5.1.

Calculation Chain: From Ray Tracing to Module Power Output 70 3.5.1.1. Inclusion of the Irradiation Spectrum 73 3.5.1.2.

Calculation of Module Output Power 74 3.5.1.3. Outlook: Energy Yield Calculation 75 3.5.2. Application Examples 76 3.

5.2.1. Calculation of Short Circuit Current and Power Output 76 3.5.2.2. Current Loss Analysis: Standard Testing Conditions vs.

Field Conditions 79 3.6. Overview of Optical Simulation Tools for PV Devices 80 3.6.1. Analysis of Solar Cells 80 3.6.2.

Analysis of PV Modules and Their Surrounding 82 3.6.3. Further Tools Which Are not Publicly Available 82 Acknowledgments 85 References 85 4 Optical Modelling and Simulations of Thin-Film Silicon Solar Cells 93 Janez Krc, Martin Sever, Benjamin Lipovsek, Andrej Campa and Marko Topic 4.1. Introduction 94 4.2. Approaches of Optical Modelling 95 4.

2.1. One-Dimensional Optical Modelling 96 4.2.2. Two- and Three-Dimensional Rigorous Optical Modelling 97 4.2.3.

Challenges in Optical Modelling 97 4.3. Selected Methods and Approaches 98 4.3.1. Finite Element Method 98 4.3.2.

Coupled Modelling Approach 100 4.4. Examples of Optical Modelling and Simulations 102 4.4.1. Texture Optimization Applying Spatial Fourier Analysis 103 4.4.2.

Model of Non-Conformal Layer Growth 110 4.4.3. Optical Simulations of Tandem Thin-Film Silicon Solar Cell 118 4.5. The Role of Illumination Spectrum 129 4.6. Conclusion 133 Acknowledgement 134 References 135 5 Modelling of Organic Photovoltaics 141 5.

1. Introduction to Organic Photovoltaics 141 5.2. Performance of Organic Photovoltaics 143 5.3. Charge Transport in Organic Semiconductors 145 5.4. Energetic Disorder in Organic Semiconductors 150 5.

5. Morphology of Organic Materials 153 5.6. Considerations for Photovoltaics 155 5.6.1. Excitons in Organic Semiconductors 155 5.6.

2. Optical Absorption in Organic Photovoltaics 160 5.6.3. Carrier Harvesting in Organic Photovoltaics 161 5.7. Simulation Methods of Organic Photovoltaics 163 5.7.

1. Lattice Morphologies and Device Geometry 163 5.7.2. Gaussian Disorder Model 164 5.7.3. Kinetic Monte Carlo Methods 164 5.

7.4. Electrostatic Interactions 168 5.7.5. Neighbour Lists 169 5.8. Considerations When Modelling Organic Photovoltaics 169 5.

8.1. The Next Steps for OPV Modelling 171 Acknowledgements 172 References 172 6 Modeling the Device Physics of Chalcogenide Thin Film Solar Cells 177 Nima E. Gorji and Lindsay Kuhn 6.1. Introduction 177 6.2. Kosyachenko''s Approach: Carrier Transport 178 6.

3. Demtsu-Sites Approach: Double-Diode Model 181 6.4. Kosyachenko''s Approach: Optical Loss Modeling 184 6.5. Karpov''s Approach 186 6.6. Conclusion 187 Acknowledgements 188 References 188 7 Temperature and Irradiance Dependent Efficiency Model for GaInP-GaInAs-Ge Multijunction Solar Cells 191 Monika Freunek Mueller, Bruno Michel and Harold J.

Hovel 7.1. Motivation 191 7.2. Efficiency Model 196 7.3. Results And Discussion 209 7.4.

Conclusions 211 7.5. Acknowledgments 211 References 212 Appendix: Shockley-Queisser-Modell Calculations 213 8 Variation of Output with Environmental Factors 217 Youichi Hirata, Yuzuru Ueda, Shinichiro Oke and Naotoshi Sekiguchi 8.1. Conversion Efficiency and Standard Test Conditions (STC) 218 8.2. Variation of I-V curve with Each Environmental Factor 218 8.2.

1. Irradiance 219 8.2.2. Cell Temperature 221 8.2.3. Spectral Response 222 8.

3. Example of Measurement of Spectral Distribution of Solar Radiation 222 8.3.1. Example of Changes with Weather 223 8.3.2. Spectral Variation with Season 225 8.

3.3. Effect of Variation in Spectral Solar Radiation 226 8.4. Irradiance 227 8.5. Effects on Performance of PV Modules/Cells 229 8.5.

1. System Configurations and Measurements 229 8.5.2. Evaluation Methods 231 8.5.2.1.

Performance Ratio 231 8.5.2.2. Effective Array Peak Power of PV Systems 233 8.5.3. Measurement Results 233 8.

5.3.1. Performance Ratios 233 8.5.3.2. Degradation Rates 234 8.

6. Cell Temperature 236 8.6.1. Output Energy by Temperature Coefficient 236 8.6.2. Output Energy with Different Installation Method 237 8.

7. Results for Concentrated Photovoltaics 239 8.7.1. Introduction 239 8.7.2. Field Test of a CPV Module 239 8.

7.3. Decline of Efficiency of the Early-Type CPV Module 239 8.7.4. Influences of the Degradation 241 Acknowledgments 243 References 244 9 Modeling of Indoor Photovoltaic Devices Monika Freunek (Müller) 9.1. Introduction 245 9.

1.1. Brief History of IPV 246 9.1.2. Characteristics of IPV Modeling 247 9.2. Indoor Radiation 248 9.

2.1. Modeling Indoor Spectral Irradiance 250 9.3. Maximum Efficiencies 251 9.3.1. Intensity effects 255 9.

4. Demonstrated Efficiencies and Further Optimization 257 9.5. Characterization and Measured Efficiencies 261 9.5.1. Irradiance Measurements 261 9.6.

Outlook 262 9.7. Acknowledgement 264 References 264 10 Modelling Hysteresis in Perovskite Solar Cells 267 James M Cave and Alison B Walker 10.1. Introduction to Perovskite Solar Cells 267 Acknowledgements 277 References 277 Index 000.