Photovoltaics: System Design and Practice

With the explosive growth in PV (photovoltaic) installations globally, the sector continues to benefit from important improvements in manufacturing technology and the increasing efficiency of solar cells. this timely handbook brings together all the latest design, layout and construction methods for entire PV plants in a single volume. Coverage includes procedures for the design of both stand–alone and grid–connected systems as well as practical guidance on typical operational scenarios and problems encountered for optimum PV plant performance. Key features: plant energy yield results from the author′s own operational experience, with tables showing the measuring results of long–term monitoring data of up to 18 years and normalized representation of energy yield/production a discussion of the solar resource worldwide detailed treatment of the design and operation of solar cells for the reader to appreciate possible technical developments and improvements in the future a description of PV plant components such as solar modules, solar generators, accumulators, charge controllers and inverters,with emphasis on their optimum co–operation in the entire PV system in order to obtain the maximum possible energy yield and reliability in–depth coverage of the principles of lightning and overvoltage protection of PV plants guidelines on how to calculate the yield of grid–connected PV plants and the data needed for the calculations used in man locations across Europe, Africa, North and South America, Asia and Australia problems and solutions for engineers and advanced students to test their knowledge This comprehensive resource will benefit electrical engineer and other electrical professionals in PV systems, especially designers and installers of PV plants or the product manufacturing and testing supply chain. Advanced students on renewable energy courses will find this useful background reading and it will be an invaluable desk reference for PV plant builders and owners.

Foreword xiii Preface xv About the Author xvii Acknowledgements xix Note on the Examples and Costs xxi List of Symbols xxiii 1 Introduction 1 1.1 Photovoltaics – What’s It All About? 1 1.2 Overview of This Book 1 1.3 A Brief Glossary of Key PV Terms 10 1.4 Recommended Guide Values for Estimating PV System Potential 14 1.5 Examples 24 1.6 Bibliography 25 2 Key Properties of Solar Radiation 27 2.1 Sun and Earth 27 2.2 Extraterrestrial Radiation 31 2.3 Radiation on the Horizontal Plane of the Earth’s Surface 32 2.4 Simple Method for Calculating Solar Radiation on Inclined Surfaces 39 2.5 Radiation Calculation on Inclined Planes with Three–Component Model 49 2.6 Approximate Annual Energy Yield for Grid–Connected PV Systems 68 2.7 Composition of Solar Radiation 71 2.8 Solar Radiation Measurement 71 2.9 Bibliography 76 3 Solar Cells: Their Design Engineering and Operating Principles 79 3.1 The Internal Photoelectric Effect in Semiconductors 79 3.2 A Brief Account of Semiconductor Theory 81 3.3 The Solar Cell: A Specialized Semiconductor Diode With a Large Barrier Layer that is Exposed to Light 86 3.4 Solar Cell Efficiency 94 3.5 The Most Important Types of Solar Cells and the Attendant Manufacturing Methods 108 3.6 Bifacial Solar Cells 122 3.7 Examples 122 3.8 Bibliography 124 4 Solar Modules and Solar Generators 127 4.1 Solar Modules 127 4.2 Potential Solar Cell Wiring Problems 138 4.3 Interconnection of Solar Modules and Solar Generators 149 4.4 Solar Generator Power Loss Resulting from Partial Shading and Mismatch Loss 160 4.5 Solar Generator Structure 166 4.6 Examples 217 4.7 Bibliography 221 5 PV Energy Systems 223 5.1 Stand–alone PV Systems 223 5.2 Grid–Connected Systems 262 5.3 Bibliography 389 6 Protecting PV Installations Against Lightning 395 6.1 Probability of Direct Lightning Strikes 395 6.2 Lightning Strikes: Guide Value; Main Effects 398 6.3 Basic Principles of Lightning Protection 400 6.4 Shunting Lightning Current to a Series of Down–conductors 402 6.5 Potential Increases; Equipotential Bonding 404 6.6 Lightning–Current–Induced Voltages and Current 408 6.7 PV Installation Lightning Protection Experiments 432 6.8 Optimal Sizing of PV Installation Lightning Protection Devices 459 6.9 Recommendations for PV Installation Lightning Protection 470 6.1 Recap and Conclusions 484 6.11 Bibliography 485 7 Standardized Representation of Energy and Power of PV Systems 487 7.1 Introduction 487 7.2 Standardized Yield, Losses and Performance Ratio 487 7.3 Normalized Diagrams for Yields and Losses 491 7.4 Normalized PV Installation Power Output 495 7.5 Anomaly Detection Using Various Types of Diagrams 502 7.6 Recap and Conclusions 506 7.7 Bibliography 506 8 PV Installation Sizing 507 8.1 Principal of and Baseline Values for Yield Calculations 507 8.2 Energy Yield Determination for Grid–Connected Systems 523 8.3 Sizing PV Installations that Integrate a Battery Pack 533 8.4 Insolation Calculation Freeware 549 8.5 Simulation Software 550 8.6 Bibliography 9 The Economics of Solar Power 551 9.1 How Much Does Solar Energy Cost? 553 9.2 Grey Energy; Energy Payback Time; Yield Factor 562 9.3 Bibliography 566 10 Performance Characteristics of Selected PV Installations 569 10.1 Energy Yield Data and Other Aspects of Selected PV Installations 569 10.2 Long Term Comparison of Four Swiss PV Installations 614 10.3 Long Term Energy Yield of the Burgdorf Installation 617 10.4 Mean PV Installation Energy Yield in Germany 619 10.5 Bibliography 620 11 In Conclusion… 623 Annex A: Calculation Tables and Insolation Data 633 A1 Insolation Calculation Tables 633 A2 Aggregate Monthly Horizontal Global Irradiance 634 A3 Global Insolation for Various Reference Locations 634 A4 R B Factors for Insolation Calculations Using the Three–Component Model 648 A5 Shading Diagrams for Various Latitudes 673 A6 Energy Yield Calculation Tables 676 A7 kT and kG Figures for Energy Yield Calculations 681 A8 Insolation and Energy Yield Calculation Maps 683 A8.1 Specimen polar shading diagram Appendix B: Links; Books; Acronyms; etc. 691 B1 Links to PV Web Sites 691 B2 Books on Photovoltaic and Related Areas 693 B3 Acronyms 695 B4 Prefixes for Decimal Fractions and Metric Multiples 696 B5 Conversion Factors 696 B6 Key Physical Constants 696 Index 697