A Comprehensive Guide to Solar Energy Systems : With Special Focus on Photovoltaic Systems

In spite of Europe leading global solar developments for many years, it is currently in a transition phase, trailing far behind the rapidly growing solar markets in Asia and in the United States. Last year was another disappointing year for solar in Europe. With only 6.7 GW of newly installed PV capacity in 2016, the European solar power market shrank by 22% year-on-year. This drop comes after a small increase in 2015 that followed several years of market contraction, which started in 2012. This contraction began as a result of the European solar pioneering countries slashing their previous lucrative feed-in tariff incentive programs.Last year, Europe's installation volume dropped by 1.9 to 6.7 GW from 8.6 GW in 2015. The 2016 PV additions are basically level with the annual PV capacity that was added 7 years earlier in 2009, Europe installed 6.6 GW on its way up to its 22.5 GW climax in 2011. The European solar PV annual grid connections from 2000 to 2016 for selected countries are given in Fig. .1. Leading European Solar Markets The European leading solar market remained the same in 2016 as it was in 2015: the United Kingdom achieved that title for the 3rd year in a row. However, with only 1.97 GW grid connected in the United Kingdom, newly installed capacity decreased by 52% from the 4.1 GW, added the year before. The UK government's abandoning solar support is the main reason for Europe's demand drop in 2016. There was only one short spike in the United Kingdom in 2016 when 1.2 GW was grid-connected by March in response to the Renewable Obligation Certificate Scheme's termination for larger solar systems at the end of the first quarter; for the rest of the year, monthly PV additions remained mostly below 50 MW. A cut of the country's other solar support mechanism, a feed-in tariff (FIT) for small installations, had been announced a few days after the Climate Summit in Paris in December 2015. The UK's Solar Trade Association published a study in June 2016 stating that one out FIGURE 3. Cover Front matter Copyright Contributors Preface Part 1 - Introduction 1 - Why Solar Energy? 1.1 - Introduction 1.2 - How Much Solar Energy Falls on the Earth and How Much is Used to Make Electricity? 1.3 - Types of Technology That Can Harness Solar Energy 1.4 - Why We Need to Develop Solar Energy 1.5 - The Difficulties With Harnessing Solar Energy 1.6 - Is Harnessing Solar Energy Cost Effective? 1.7 - A Comparison of Solar PV Installed Capacity With Other Renewable Forms of Energy 1.8 - The Future of Solar Energy 1.9 - Conclusions Acknowledgment References Part 2 - Solar Energy Resource World Wide 2 - Solar Power Development in China 2.1 - Introduction 2.2 - Photovoltaic Manufacture 2.2.1 - Production 2.2.2 - Photovoltaic Technology 2.2.2.1 - Technical Efficiency 2.2.2.2 - Economics 2.2.3 - Photovolt†aic Export 2.3 - Industrial Policy 2.3.1 - Laws and Regulations 2.3.2 - Government Funds Available for Solar Energy 2.3.3 - Price Policy for Photovoltaic Power 2.3.4 - Special Projects 2.4 - Future Solar Energy in China 2.4.1 - Development Target 2.4.2 - Development Orientation 2.4.3 - Special Schemes 2.4.3.1 - Photovoltaic Pioneer Program 2.4.3.2 - Other Programs 2.5 - Conclusions References 3 - Solar Power in Europe: Status and Outlook 3.1 - The Past: Solar Developments in Europe (2000–16) 3.1.1 - Leading European Solar Markets 3.1.2 - Market Segmentation 3.2 - The Future: 5-Year Market Outlook (2017–21) 3.2.1 - Main Reasons for Solar Market Growth in Europe 3.2.2 - Solar Markets’ Growth Scenarios 3.2.3 - European Countries’ Solar Prospects 3.3 - Solar in the European Electricity System 3.3.1 - Inflexible Energy Generation Needs to be Strongly Reduced Between Now and 2030 3.3.2 - Accelerate the Energy Transition via Reliable and Ambitious Long-Term Signals 3.4 - Policy Recommendation for Solar in Europe 3.5 - Conclusions References 4 - Solar Power in the USA—Status and Outlook 4.1 - Overall US Market Indicators 4.1.1 - Reducing Soft Costs 4.1.2 - Federal Policy 4.2 - The United States as a Patchwork of States 4.2.1 - Leading States 4.3 - US Solar Energy Market Outlook 4.4 - The United States as a Driver of Innovation 4.4.1 - “Profoundly Disconnected”: The Need for Workforce Development and Educator Training 4.4.2 - Technological and Financial Innovations 4.4.3 - System Upgrades 4.4.4 - A Vision for the Future of the US Grid—The Internet of Interoperable Microgrids References Further Reading 5 - Sustainable Solar Energy Collection and Storage for Rural Sub-Saharan Africa 5.1 - Introduction 5.2 - Geography 5.3 - The Circular Economy Approach 5.4 - Photovoltaic Technology 5.5 - Energy, and Energy Storage, Needs of Households in Rural Africa 5.6 - Energy Storage—Battery Choices 5.7 - Carbon Footprint and Lifecycle Impact Considerations 5.8 - Resource-Efficiency and Circular Economy 5.8.1 - Critical Materials 5.8.2 - End-of-life Prospects and Compatibility With Circular Economy 5.9 - Future Solar Cell Technologies 5.10 - Conclusions References Further Reading Part 3 - Thermal Solar Energy Technology 6 - Solar Water Heaters 6.1 - Introduction 6.1.1 - The Marketing Situation of Solar Water Heaters 6.1.2 - Driving Forces for the Expansion of the Global Solar Thermal Market 6.1.3 - Existing Barriers to the Diffusion of Global Solar Thermal Market 6.2 - Working Principle of SWH Systems 6.3 - The Classification of SWH Systems 6.3.1 - Passive and Active Systems 6.3.2 - Direct and Indirect Systems 6.3.3 - SWH Systems in Different Solar Collector Configurations 6.3.3.1 - Low Temperature Solar Collectors 6.3.3.2 - High Temperature Solar Collectors 6.3.3.3 - Comparison of the Evacuated-Tube and Flat-Plate Collectors 6.4 - Most Advanced Technologies of SWHs 6.4.1 - SWHs With Phase Change Materials 6.4.2 - SWHs With Loop Heat Pipe 6.4.3 - SWHs With Microchannel Heat Pipe Array References 7 - Concentrating Solar Thermal Power 7.1 - Introduction 7.2 - Parabolic-Trough Collectors 7.2.1 - Main Components 7.2.2 - Working Fluids for PTC 7.2.3 - Main Applications of PTC 7.3 - Central Receiver Systems 7.3.1 - Main Components 7.4 - Compact Linear Fresnel Concentrators 7.5 - Parabolic Dishes 7.6 - Technology Trends References Part 4 - Photo Voltaic Solar Energy 8 - Photovoltaics: The Basics 8.1 - Introduction 8.2 - Light Absorption in Materials and Excess Carrier Generation 8.2.1 - Carrier Generation 8.2.2 - Carrier Recombination 8.2.3 - Excess Carrier Concentration 8.3 - Photovoltaic Effect and Basic Solar Cell Parameters 8.3.1 - Photovoltaic Effect 8.3.2 - I–V Characteristics and Basic Parameters of Photovoltaic Cells 8.3.3 - In-Series and In-Parallel Connection of PV Cells 8.4 - Principles of Solar Cell Construction 8.4.1 - PV Cell Efficiency Limit 8.4.1.1 - Tandem Structures 8.4.2 - Wafer-Based and Thin Film Construction 8.4.3 - Losses in Real PV Cell Structures 8.4.3.1 - Optical Losses 8.4.3.2 - Recombination Losses 8.4.3.3 - Electrical Losses 8.5 - Photovoltaic Modules—Principles and Construction 8.5.1 - PV Modules and Their Characteristics 8.5.2 - PV Module Optical, Mechanical, and Thermal Properties 8.5.3 - Local Shading and Hot Spot Formation References Further reading 9 - Crystalline Silicon Solar Cell and Module Technology 9.1 - Introduction 9.2 - Semiconductor Silicon 9.2.1 - Semiconductor Silicon Manufacture Technology 9.2.1.1 - The Siemens Method 9.2.1.2 - The Fluidized Bed Reactor Method 9.3 - Crystalline Silicon Wafer Fabrication 9.3.1 - Crystalline Silicon Ingot Fabrication 9.3.1.1 - Silicon Single-Crystal Ingot Fabrication 9.3.1.2 - Multicrystalline Block Fabrication 9.3.2 - The Wafering Process 9.3.3 - Ribbon Silicon 9.4 - Crystalline Silicon PV Cell Design and Fabrication Technology 9.4.1 - BSF Solar Cells 9.4.2 - High Efficiency Cells 9.4.2.1 - PERC and PERL Cells 9.4.2.2 - PERT, TOPCon, and Bifacial Cells Bifacial Solar Cells 9.4.2.3 - IBC Cells 9.4.2.4 - Heterojunction Technology Cells 9.4.3 - Si Wafer-Based Multijunction Cells 9.5 - Crystalline Si Module Design and Fabrication 9.5.1 - Standard PV Module Fabrication Technology 9.5.2 - Emerging Module Technologies 9.5.2.1 - Shingled Cell Modules 9.5.2.2 - SmartWires Contact Technology 9.5.3 - Module Reliability and Durability 9.6 - Conclusions References Further Readings 10 - CdTe Solar Cells 10.1 - Introduction 10.2 - The CdTe Solar Cell: History, Layers, and Processes 10.2.1 - Transparent Conductive Oxide (TCO) 10.2.2 - The Window Layer 10.2.3 - CdTe Absorber Layer 10.2.4 - The Chloride Process 10.2.5 - Back-Contacting 10.2.6 - General CdTe Solar Cell Production Notes 10.3 - Looking Forward—Voltage, Doping, and Substrate Cells 10.3.1 - Substrate Cells 10.3.2 - Open Circuit Voltage Limitations 10.4 - Conclusion References 11 - An Overview of Hybrid Organic–Inorganic Metal Halide Perovskite Solar Cells 11.1 - Introduction 11.2 - Thin Film Fabrication/Formation 11.2.1 - Single Step Deposition 11.2.2 - Two Step Sequential Deposition 11.2.3 - Two Step Vapor Assisted Deposition 11.2.4 - Thermal Vapor Deposition 11.3 - Perovskite Solar Cell Device Structure 11.3.1 - Mesoporous Scaffold Structure 11.3.2 - Planar Structure 11.4 - Device Optimization 11.4.1 - Solvent to Film Optimization 11.4.2 - Band Gap Optimization 11.4.3 - Electron and Hole Transporting Materials Optimization 11.5 - Stability Issues and Challenges of Perovskite Solar Cells 11.5.1 - Stability Issues 11.5.2 - J–V Hysteresis 11.6 - Summary References 12 - Organic Photovoltaics 12.1 - Introduction 12.2 - Operating Principles 12.3 - Device Structure 12.4 - Challenges and Opportunities for Improved Performance 12.4.1 - Increasing Power Conversion Efficiency 12.4.2 - Improving Long-Term Stability 12.4.3 - Minimizing the Cost of Materials and Device Fabrication 12.5 - Conclusion References 13 - Upconversion and Downconversion Processes for Photovoltaics 13.1 - Introduction 13.2 - Upconversion 13.2.1 - Upconversion Materials 13.2.2 - PV Devices With Upconverters 13.2.2.1 - GaAs Solar Cells 13.2.2.2 - Crystalline Silicon Solar Cells 13.2.2.3 - Amorphous Silicon Solar Cells 13.2.2.4 - Dye-Sensitized Solar Cells 13.2.2.5 - Organic Solar Cells 13.2.2.6 - Perovskite Solar Cells 13.2.3 - Approaches to Increase Upconversion Performance Enhancement 13.2.3.1 - Material Optimization 13.2.3.1.1 - Ln3+-Based Upconverters 13.2.3.1.2 - Organic Upconverters 13.2.3.2 - Material Environment 13.2.3.2.1 - Plasmonics and Photonics 13.2.3.2.2 - Spectral Concentration 13.3 - Downconversion 13.3.1 - Downconversion Materials 13.3.2 - PV Devices With Downconverters 13.3.2.1 - Silicon and GaAs-Based Solar Cells 13.3.2.2 - Dye-Sensitized Solar Cells 13.3.2.3 - Organic Solar Cells 13.3.2.4 - Perovskite Solar Cells 13.4 - Conclusions References Further Reading 14 - Advanced Building Integrated Photovoltaic/Thermal Technologies 14.1 - Introduction 14.2 - Building Integrated Thermal Electric Roofing System 14.3 - BIPVT Solar Roof 14.3.1 - Design and Manufacture of the Novel FGM Panel 14.3.2 - Assembling of the BIPVT 14.3.3 - Integration of a Multifunctional Roofing System 14.4 - Modeling Procedures and Performance Evaluation of the Multifunctional BIPVT Panel 14.4.1 - Laboratory Testing Setup 14.4.2 - Estimation of Heat Collection 14.4.3 - Estimation of Electricity Generation 14.4.4 - Overall Efficiency and Comparisons With Other Relevant PVT Collectors 14.5 - Summary and Conclusions Acknowledgment References 15 - Integration of PV Generated Electricity into National Grids 15.1 - Introduction: Rapid Growth of the Solar PV Industry 15.2 - Why We Need to Integrate Solar Power into National Grids 15.3 - How Solar PV Fits in 15.4 - Is the Duck Relevant to Solar PV in United Kingdom? 15.5 - Effect of Growth in Small Distributed Installations 15.6 - ‘Nonsynchronous’ Inverter Type Generators Supporting the Network 15.7 - Converter Technology 15.8 - Conclusions References 16 - Small-Scale PV Systems Used in Domestic Applications 16.1 - Introduction 16.2 - Electrical Characteristics of PV Cells/Modules 16.3 - Features of Converter Topologies in PV Systems 16.3.1 - Electrical Requirements of Grid-Tied Inverters 16.3.2 - Commonly Used Grid-Tied Converter Topologies 16.3.3 - Emerging Converter Topologies 16.3.3.1 - Cascaded Multilevel Modular Integrated Converters in Small-scale Grid-Tied PV Systems [1,4] 16.3.3.2 - Grid-Connected Current Source Inverter With Feed Forward Control [3] 16.4 - Configurations of Grid-Tied PV Systems 16.5 - Issues on PV Systems and Cell and Module Level Failures 16.5.1 - Shading 16.5.2 - Hot Spots 16.5.3 - Micro-cracks 16.5.4 - Delamination and Moisture Ingress 16.5.5 - Snail Trail Contamination 16.5.6 - Interconnects 16.5.7 - Potential Induced Degradation (PID) Effect [5] 16.5.8 - Encapsulate Discoloration 16.6 - Conclusions References 17 - Energy and Carbon Intensities of Stored Solar Photovoltaic Energy 17.1 - The Need for Storage 17.2 - Key Characteristics for Storage 17.3 - Net Energy Analysis of Storing and Curtailing Solar PV Resources 17.4 - The Carbon Footprint of Storing Solar PV 17.5 - Conclusions References 18 - Thin Film Photovoltaics 18.1 - Introduction 18.2 - Thin Film Cell Configurations 18.2.1 - Amorphous Silicon 18.2.2 - Cadmium Telluride Solar Cells 18.2.3 - CIGS Solar Cells 18.2.4 - Perovskite 18.3 - Deposition and Growth Techniques 18.4 - Flexible Cell Formations 18.5 - Challenges 18.6 - Conclusions References Part 5 - Environmental Impacts of Solar Energy 19 - Solar Panels in the Landscape 19.1 - Introduction 19.1.1 - What Is Landscape? 19.2 - Solar Installation Types 19.2.1 - Building-Mounted Panels 19.2.2 - Integrated Materials 19.2.3 - Free-Standing Solar Farms 19.2.4 - Floating Solar Farms 19.3 - Key Visual Elements 19.3.1 - How People Experience Solar Farms 19.3.2 - Impressions of a Solar Farm 19.4 - Environmental Issues in Planning 9.4.1 - Landscape and Visual Effects 9.4.2 - Effects on Land Use 9.4.3 - Other Environmental Issues 19.5 - Offset Mitigation 19.6 - Concluding Remarks References 20 - Solar Energy Development and the Biosphere 20.1 - Introduction 20.2 - Solar Energy Effectors and Potential Effects on the Environment 20.2.1 - Land Requirements 20.2.2 - Land-Use and Land-Cover Change 20.2.3 - Surface Grading and Vegetation Removal 20.2.4 - Hydrologic Changes and Water Degradation 20.2.5 - Changes in Land-Surface Temperature, Albedo, and Microclimate 20.3 - Ecological Impacts and Responses 20.3.1 - Habitat Fragmentation 20.3.2 - Roads, Transmission Lines, and Fences 20.3.3 - Panels and Mirrors 20.3.4 - Air-Cooled Condensers and High-Energy Flux 20.4 - Summary References 21 - Energy Return on Energy Invested (EROI) and Energy Payback Time (EPBT) for PVs 21.1 - Introduction 21.2 - Methods of EROI Analysis 21.2.1 - Introduction to Methods of EROI Analysis 21.2.2 - Energy Payback Times 21.2.3 - Overlapping Energy Input Accounting Methods 21.2.3.1 - Confusion in PV EROI Results Caused by Inconsistencies in Objectives and Energy Input Accounting 21.2.4 - Pathways to PV Net Energy Analysis Using CED 21.2.4.1 - EROIel: Energy Output Expressed in Terms of Direct Energy 21.2.4.2 - EROIPE-eq: Energy Output Expressed in Terms of Equivalent Primary Energy 21.2.4.3 - The Cumulative Energy Demand (CED) Metric 21.2.4.4 - The Nonrenewable Cumulative Energy Demand (nr-CED) Metric 21.3 - Results of EROI Analysis of PV Systems, Harmonization and Trends Over Time 21.3.1 - Results of a UK Case Study Comparing PV and Nonrenewable EROIs 21.3.2 - Results From Harmonizing EROI and EPBT Analyses and Trends in the Industry 21.3.3 - Future Possibilities References Further Reading 22 - Life Cycle Analysis of Photovoltaics: Strategic Technology Assessment 22.1 - Introduction 22.2 - Life Cycle Analysis Methodology 22.2.1 - Interpretation and Reporting 22.3 - Current Photovoltaic Status 22.3.1 - Major Technologies 22.3.2 - Production Sites and Electricity Mixes 22.4 - Current Photovoltaic Life Cycle Analysis Results 22.4.1 - Fixed-Tilt Ground-Mounted Photovoltaic Systems 22.5 - Technology Roadmaping 22.5.1 - Feedstock and Ingot Growth 22.5.2 - Wafering 22.5.3 - Cell Processing 22.5.4 - Technological Scenarios 22.6 - Prospective Life Cycle Analysis of Future Designs 22.6.1 - Data Collection, Modeling, and Inventory Analysis 22.6.2 - Uncertainty Analysis 22.6.2.1 - Parameter Uncertainty 22.6.2.2 - Scenario Uncertainty 22.7 - Results 22.7.1 - Cells and Modules 22.7.2 - Balance of System 22.8 - Conclusion References Part 6 - Economics and Future of Solar Energy 23 - Materials: Abundance, Purification, and the Energy Cost Associated with the Manufacture of Si, CdTe, and CIGS PV 23.1 - Introduction 23.2 - Critical Metals 23.3 - Material Requirements for PV 23.3.1 - Mining and Refining Materials for PV 23.3.2 - Aluminum 23.3.3 - Gallium 23.3.4 - Copper 23.3.5 - Selenium 23.3.6 - Tellurium 23.3.7 - Silicon 23.3.8 - Silver 23.3.9 - Zinc 23.3.10 - Cadmium 23.3.11 - Germanium 23.3.12 - Indium 23.4 - Energy Costs of Materials 23.5 - Conclusion References 24 - Global Growth Trends and the Future of Solar Power: Leading Countries, Segments, and Their Prospects 24.1 - Introduction 24.2 - Solar Growth Trends 24.3 - Future Market Growth Potential 24.4 - Segmental Growth 24.5 - Industrial Growth 24.6 - Conclusions References 25 - Optimal Renewable Energy Systems: Minimizing the Cost of Intermittent Sources and Energy Storage 25.1 - Introduction 25.2 - Renewable Energy Microeconomic Considerations 25.3 - Economic Theory of Renewable Energy Intermittency 25.4 - Economics of Renewable Energy Intermittency: Empirical Example from Vermont 25.5 - Extensions and Conclusions References index Our book gives an all-round view of solar energy with a special focus on technical issues surrounding photovoltaic cells. The 25 chapters are divided into the following six sections: Introduction; Solar Energy Resource and Worldwide Development; Thermal Solar Energy Technology; Photovoltaic Solar Energy—Generation of Electricity; Environmental Impacts of Solar Energy; Economics, Financial Modeling, and Investment in PVs, Growth Trends, and the Future of Solar Energy. In more detail, the book includes chapters on the following areas:• Scientific aspects (basic theory of photovoltaic solar energy, global potential for producing electricity from the sun’s energy);• Wind energy in China, Europe, Africa, and the USA, to give a flavor of developments in very different countries but all with the same aim of reducing global warming while providing affordable, abundant, and sustainable energy;• Thermal solar power in solar heaters, concentrated solar systems.• Photovoltaics in all its different forms—crystalline silicon cells, cadmium telluride cells, perovskite cells, and organic cells;• Large scale PV Integrated technologies (buildings);• Integration into national grids;• Small scale PV systems;• Storing energy from PVs;• Environmental issues and comparisons;• Materials’ abundance, purification, and energy cost for Si, CdTe, and CIGS photovoltaics;• Life Cycle Analysis and Energy Return on Investment;• Growth trends and the future of solar power;• Minimizing the cost of resolving variability and energy storage.It is hoped that the book will act as a springboard for new developments and perhaps lead to synergistic advances by linking ideas from different chapters. A Comprehensive Guide to Solar Energy Systems: With Special Focus on Photovoltaic Systems, the most advanced and research focused text on all aspects of solar energy engineering, is a must have edition on the present state of solar technology, integration and worldwide distribution. In addition, the book provides a high-level assessment of the growth trends in photovoltaics and how investment, planning and economic infrastructure can support those innovations. Each chapter includes a research overview with a detailed analysis and new case studies that look at how recent research developments can be applied. Written by some of the most forward-thinking professionals, this book is an invaluable reference for engineers. Contains analysis of the latest high-level research and explores real world application potential in relation to developments Uses system international (SI) units and imperial units throughout to appeal to global engineers Offers measurable data written by a world expert in the field on the latest developments in this fast moving and vital subject