Solar Electric Power Generation - Photovoltaic Energy Systems

Transcription

1 Stefan C.W. Krauter Solar Electric Power Generation - Photovoltaic Energy Systems Modeling of Optical and Thermal Performance, Electrical Yield, Energy Balance, Effect on Reduction of Greenhouse Gas Emissions With 107 Figures and 60 Tables 4y Springer

2 Contents Preface Foreword by Dr. Franz Alt Foreword by Dr. Hermann Scheer Table of Contents VII IX XIII XV 1 Introduction World's Energy Consumption CO,-Emissions by Humankind Global warming by CO Measures of CO 2 -Diminution Conventional and Renewable Sources of Energy Approach Production Yield Balance Optimization 18 2 Photovoltaics Brief History Photovoltaic Effect Photovoltaic Generator Electrical properties Equivalent Electrical Circuit Bypass Diodes Electrical Terminals Parallel Strings Mechanical Properties Sandwich Lamination Framing Fixing and Mounting Properties of PV Generators in Operation Conditions Mounting of PV Modules Future Development of Photovoltaics Research Funding for Photovoltaics 43

3 XVI Contents 2.8 Market Development of Photovoltaics 44 Inverters Autonomous Operation Inverters for Electrical Grid Injection Types of Inverters External Commutated Inverters Self Commutated Inverters Inverters Based on PWM Electrical Grid Connection Voltage Levels of Electrical Grids Boundary Values of Electrical Grids Long-Distance Transport of Electricity 57 Storage Lead Sulphide Acid Battery Principle Gassing Specific Gravity (SG) Operating Temperature Self-Discharge Deep Discharge Sulfation Battery Types Other Type of Batteries Nickel Cadmium Battery Nickel Hydride Batteries Lithium-Ion Batteries Fuel Cells Principle Types of Fuel Cells 74 PV-Systems in the Tropics Pre-installation Issues Additional Considerations for Planning Determination of Load Requirements 77

4 Contents XVII Dynamics of Project Development vs. Time Constrains Financing Importation Language Barriers Technical Issues Mounting Fixation of PV Modules Wiring of PV Generator Theft Prevention Safety Considerations Non-MPP Operation of PV Generator Energy Storage Battery Types Nominal Voltage Level Power Conditioning Equipment Switching Devices Ventilation Charge-Controllers Operation and Maintenance Pollution & Degradation of System Components Monitoring Further Recommendations Concluding Remarks for PV in the Tropics. 86 Energy Consumption for the Set-up of a PV Power Plant Preliminary Remarks Differentiation of the Model Cases Equivalent Primary Energy Consumption Preparation of Raw Materials for Production Development of a Deposit Release (Exploitation) Transport Preparation for Production Construction Work and Buildings Direct Energy Consumption at the Production Process 94

5 XVIII Contents 6.4 Production of Solar Cells Production of Technical Silicon (MG-Si) Metallurgical-Grade Silicon (MG-Si) to Semiconductor-Grade Poly-Silicon (EG-Si) Production of Single-Crystalline Silicon Semiconductor-Grade Silicon to Multi-Crystalline Silicon Production of Silicon Wafers (single- and multi-crystalline) Single-Crystal Wafers to Single-Crystalline Solar Cells Multi-Crystalline Wafers to Multi-Crystalline Solar Cells Production of Amorphous Silicon Solar Cells Production of Solar Cells Made of Other Semiconductors Production of PV Modules Lamination Process Integrated Laminator "Passing-Through" Laminator Production of "Encapsulated" PV modules Production of "Laminated"PV modules Electrical Power Conditioning Ill Support Structure Installation and Taking into Operation Transport Installation Setting into Operation Operation Expenses Cleaning Maintenance Use of Land Dismantling Dismantling Transport 116

6 Contents XIX Energy Yield Model to Determine the Cell Reaching Irradiance Sun's Position Relative to Earth's Surface Way of Sun's Irradiance Through the Earth's Atmosphere Solar Constant Direct Irradiance Diffuse Irradiance Albedo Angular Distribution of Yearly Irradiance in Central Europe Optical Model of Module Encapsulation Optical Interface at Boundary Layers Optical Transmittance of a Plane Slab Internal Transmission and Reflection Transmittance Through Two Slabs Transmittance Through Three Slabs Optical Transmittance Through m Slabs Simulation Results Heat Flow Input Heat Flow Input by Sky and Ground Radiation Heat Flow Input by Ambient Temperature Heat Flow Input by Irradiance Heat Transfer Inside a Module Dimensional Layout of the Thermal Model Stationary Heat Flow in the Module Non-Steady-State Heat Flow in the Module Heat Dissipation Determination of Sky Temperature Heat Dissipation by Natural Convection Heat Dissipation by Forced Convection...160

7 XX Contents Heat Transfer for Superposition of Natural and Forced Convection Model Calculation Validation of Thermal Modeling Electrical Modeling Current Other Electrical Parameters PV Grid Injection Modeling of Inverters Limiting Factors for the Design of PV Power Plants System Layouts Electrical Yield of a Reference System Energy Input by Dumping and Recycling Separation of Materials Energy Input by Recycling Total Energy Balance Commutated Energy Expense Models for Energy Balances Input-Output Analysis Process Chain Analysis CO 2 Reducing Effects by the Use of PV Specific Emission Balance Effect of PV on Reduction of CO 2 Emissions in Germany Variation of Location Optimization Improvement of Irradiance on a Solar Cell Improvement of Irradiance by Tracking the Sun Improvement of Cell Irradiance by Reduction of Optical Reflection Structuring of the PV Module Surface Selective Structuring Improved Matching of the Refractive

8 Contents XXI Indices of the Module Encapsulation Layers Additional Anti-Reflective Coating Reduction of Expenses for Mounting Substitution of Building Components Solar Roof Tiles Solar Facades Thermal Enhancement of PV Modules Real Operating Cell Temperatures Under Tropical Conditions Preliminary Work for the Reduction of Temperatures in PV Modules Development of a Thermally Improved Prototype Construction, Operation and Measurement of TEPVIS in Africa The Integrated Solar Home System (I-SHS) Composition of the System Benefits of the I-SHS Further Development Summary Appendix List of Symbols and Abbreviations Tables 229 Literature 259