Building Integrated Photovoltaic Thermal Systems For Sustainable Developments

Basant Agrawal and G. N. Tiwari Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi, India

RSC Publishing Contents

Chapter 1 Solar Radiation and its Availability on Earth

1.1 Introduction 1 1.2 The 1 1.3 The Earth 3 1.4 Apparent Path of the Sun 3 1.5 Solar Radiation on the Earth 5 1.6 Variation of Radiation in Extraterrestrial and Terrestrial Regions 7 1.7 Terminology Associated with Solar Radiation 7 1.7.1 Air Mass 7 1.7.2 Diffuse Radiation 9 1.7.3 Beam or Direct Radiation 10 1.7.4 Total Radiation or Global Radiation 10 1.7.5 Insolation 10 1.7.6 Irradiance, Radiant Exitance and Emissive Power 10 1.7.7 Latitude 11 1.7.8 Longitude 11 1.7.9 Solar Time 12 1.8 Measurement of Solar Radiation on the Earth's Surface 12 1.8.1 The Normal Incidence Pyrheliometer 13 1.8.2 The Pyranometer 14 1.8.3 The Sunshine Recorder 15 1.8.4 The World Radiometric Reference 16 1.9 Sun-Earth Geometric Relationship 17 1.9.1 The Declination 17 1.9.2 The Hour Angle 19 1.9.3 The Zenith Angle and the Solar Altitude Angle 19 -

RSC Energy Series No. 4 Building Integrated Photovoltaic Thermal Systems: For Sustainable Developments By Basant Agrawal and G. N. Tiwari © B. Agrawal and G. N. Tiwari 2011 Published by the Royal Society of Chemistry, www.rsc.org

Vll Vlll Contents 1.9.4 The Slope 21 1.9.5 The Surface Azimuth Angle 21 1.9.6 The Solar Azimuth Angle 21 1.9.7 The Angle of Incidence 22 1.10 Extraterrestrial Radiation on a Horizontal Surface 25 1.11 Radiation on an Inclined Surface 27 1.12 Estimation of Average Solar Radiation 30 1.12.1 Monthly Average of the Daily Total Radiation on a Horizontal Surface 30 1.12.2 Monthly Average of the Daily Diffuse Radiation on a Horizontal Surface 31 1.12.3 Beam and Diffuse Components of Daily Radiation 31 1.12.4 Beam and Diffuse Components of Hourly Radiation 32 1.13 Heat Transfer through Conduction 34 1.13.1 Thermal Conductivity 35 1.13.2 Heat Transfer through Parallel Slabs 35 1.13.3 Heat Transfer through Coaxial Cylinders 36 1.14 Heat Transfer through Convection 39 1.14.1 Dimensionless Heat Convective Parameters 39 1.14.2 Free Convection 41 1.14.3 Simplified Free Convection Relations for Air 42 1.14.4 Forced Convection 42 1.14.5 Combined Free and Forced Convection 43 1.14.6 Convective Heat Transfer Due to Wind 43 1.15 Heat Transfer through Radiation 46 1.15.1 Radiative Heat Transfer Coefficient 46 1.15.2 Sky Radiation 47 References 49 Further Reading 49

Chapter 2 Photovoltaic Technology and its Development 50

2.1 Introduction 50 2.2 Evolution of the 50 2.2.1 Intrinsic Semiconductors 51 2.2.2 Extrinsic Semiconductors 52 2.2.3 p-n Junctions 55 2.2.4 Photovoltaic Cells: Generating Electricity 57 2.2.5 The Limits to Cell Efficiency 61 2.3 Historical Developments 65 2.4 Technology Generation 68 2.4.1 First-generation Technology 68 2.4.2 Second-generation Technology 69 Contents 2.4.3 Third-generation Technology 69 2.5 Silicon Solar Cell Materials and Technology 70 2.5.1 Production of Silicon 70 2.5.2 Bulk Monocrystalline Silicon Ingot Production 70 2.5.3 Bulk Multicrystalline Silicon Ingot Production 74 2.5.4 Silicon Wafers 76 2.5.5 Silicon Ribbon and Foil Production 77 2.5.6 Crystalline Silicon Solar Cell Manufacturing Process 82 2.5.7 Thin-film Silicon Cell Approach 83 2.5.8 Transfer Technologies of Monocrystalline Thin Silicon Films onto Glass 84 2.6 Concentrator Photovoltaic Systems 85 2.7 Amorphous Silicon Solar Cells 86 2.8 Copper Indium Gallium Selenide Solar Cells 90 2.9 Cadmium Sulfide/Cadmium Telluride Solar Cells 92 2.10 Dye-sensitized Cells 94 2.11 Organic Solar Cells 96 2.12 Photovoltaic Modules and Arrays for Crystalline Silicon Solar Cells 97 References 101 Further Reading 102

Chapter 3 Thermal Comfort 103

3.1 Introduction 103 3.2 Physical Parameters 104 3.2.1 Air Temperature 104 3.2.2 Relative Humidity 105 3.2.3 Air Movement 105 3.2.4 Mean Radiant Temperature 107 3.2.5 Air Pressure 108 3.2.6 Air Ingredients 108 3.2.7 Air Electricity 108 3.2.8 Acoustics 108 3.2.9 Day Lighting 109 3.3 Physiological Parameters 109 3.3.1 Nutritional Intake 109 3.3.2 Age 109 3.3.3 Ethnic Influences 109 3.3.4 Gender Differences 109 3.3.5 Constitution 110 X Contents 3.4 Intermediate Parameters 110 3.4.1 Clothing 110 3.4.2 Metabolism 110 3.4.3 Adaption and Acclimatization 112 3.4.4 Time of the Day or Season 112 3.4.5 Occupancy 113 3.4.6 Psychological Factors 113 3.5 The Comfort Equation 113 3.5.1 Radiation 116 3.5.2 Convection 116 3.5.3 Conduction through Clothing 117 3.5.4 Evaporative Heat Loss 119 3.5.5 Respiration Heat Loss 120 3.6 Predicting the Thermal Comfort 120 3.6.1 Predicted Mean Vote Index 121 3.6.2 Predicted Percentage Dissatisfied Index 122 3.7 Recent Research and Conclusions 123 3.8 Related Standards 125 References 126 Further Reading 127

Chapter 4 Solar Heating and Cooling Concepts for Buildings 128

4.1 Introduction 128 4.2 Sol-air Temperature 129 4.2.1 Sol-air Temperature for Bare Surfaces 130 4.2.2 Sol-air Temperature for Wetted Surfaces 135 4.2.3 Sol-air Temperature for Blackened and Glazed Surfaces 139 4.3 Passive Solar Heating Systems 141 4.4 Direct Thermal Gain Systems 143 4.4.1 Sol-air Temperature and Heat Transfer for Single-glazed Windows 144 4.4.2 Sol-air Temperature and Heat Transfer for Double-glazed Windows 145 4.4.3 Sol-air Temperature and Heat Transfer for Single-glazed Windows with Reflectors 146 4.5 Indirect Thermal Gain Systems 147 4.5.1 Trombe Walls 148 4.5.2 Water Walls 150 4.5.3 Vented Trombe Walls 151 4.5.4 Phase-change Material Walls 152 4.6 Isolated Thermal Gain or Active Solar Collectors 157 4.6.1 The Thermosyphon System 157 4.6.2 The Barra System 158 4.6.3 Sunspaces 159 Contents XI 4.7 Combined Thermal Gain Systems 159 4.7.1 A Transwall 160 4.7.2 A Solarium 161 4.8 Use of Photovoltaic Arrays as a Facade 163 4.8.1 Semi-transparent Photovoltaic Arrays as a Facade 163 4.8.2 Photovoltaic Trombe Walls 165 4.8.3 Photovoltaic Integrated Phase-change Material Walls 165 4.9 Integration of Photovoltaic Arrays on the Roof 167 4.9.1 Opaque Photovoltaic Arrays Integrated on the Roof 167 4.9.2 Semi-transparent Photovoltaic Arrays Integrated on the Roof 168 References 168

Chapter 5 Implementation of Building Integrated Photovoltaic Thermal Systems and Case Studies 170

5.1 Introduction 170 5.2 Implementation in Germany 171 5.2.1 BIPV Systems on the Rooftop and as a Facade of the Mont-Cenis Academy 171 5.2.2 A BIPV System as a Rooftop in Bürstadt 173 5.2.3 A BIPV System as a Rooftop in Muggensturm 174 5.2.4 A PV Facade Integration at Lehrter Station 174 5.3 Implementation in Spain 175 5.3.1 Integration of PV Systems as Parking Cano­ pies, Pergolas and Facades at Jaen University 176 5.3.2 A BIPV System as a Rooftop and Facade at Telefonica Business Park Complex 178 5.3.3 A BIPV System as a Rooftop and Facade at Torre Garena 178 5.4 Implementation in Japan 179 5.4.1 A BIPV System as the Rooftop and Facade of the Sharp Corporation LCD Plant at Kameyama 181 5.4.2 A PV Integrated System on the Louvres of a Roof Shelter in the Itoman City Government Building 181 5.4.3 A PV Integrated Shelter for the Bus and Taxi Terminal at Kanazawa Station 182 5.4.4 The Solar Ark Building at Gifu Prefecture 182 5.5 Implementation in the United States 183 5.5.1 The PV Mounted Roof at Toyota's NAPCC Manufacturing Plant 184 Xll Contents 5.5.2 The PV Mounted Roof at Google Corporate Headquarters (Googleplex) 185 5.5.3 The PV Mounted Roof of the California State University Buildings at Hayward Campus 185 5.5.4 The Farmingdale Rooftop PV System on Long Island 186 5.6 Implementation in Korea 187 5.6.1 A Sun Room Integrated with Semi-transpar­ ent PV Modules 188 5.6.2 The BIPV System at the Samsung Institute of Engineering & Construction Technology 189 5.6.3 The PV System on the Parking Lot of Ham- pyeong World Butterfly and Insect Expo 190 5.7 Implementation in Italy 190 5.7.1 The Roof-mounted PV Plant at the Politecni- co di Milano 191 5.7.2 The Roof-mounted System with a Hybrid PVT Facade at Orbassano 192 5.7.3 The PV Modules Installed on the Rooftop in the Town of Serravalle Scrivia 194 5.7.4 The PV Modules on the Warehouse Roof of Coop's New CNNA-Prato Logistic Centre in Prato 194 5.8 Implementation in the People's Republic of China 195 5.8.1 The BIPV System on the Shaw Amenities Building of Hong Kong Polytechnic Univer­ sity 196 5.8.2 The PV Mounted Roof of the Hong Kong EMSD Headquarters 198 5.8.3 The PV System Integrated with Permanent Buildings at Shanghai World Expo 2010 198 5.8.4 The PV System at the International Garden and Flower Expo Park in Shenzhen 201 5.9 Implementation in Taiwan 201 5.10 Implementation in Australia 201 5.10.1 The BIPV System at Kogarah Town Square 202 5.10.2 The Grid-connected BIPV Power Station at Adelaide Showground 204 5.10.3 The PV System Mounted over the Tilted Roof of the Crowne Plaza Hotel in Alice Springs 205 5.10.4 The PV Integrated Facade over an Eight-story Building at Melbourne University 206 5.11 Implementation in the United Kingdom 207 5.11.1 The Solar Office at Doxford International Business Park 207 Contents хш 5.11.2 The Cladding PV Modules over the Co-operative Insurance Tower 208 5.12 Installation in India 209 5.12.1 The PV System Mounted on the Roof of the WHO South East Asia Office Building 211 5.13 Recent Research and Conclusions 212 References 215

Chapter 6 Thermal Modelling and Performance Analysis 220

6.1 Introduction 220 6.2 Assumptions 220 6.3 Thermal Modelling 221 6.3.1 A Roof-integrated Opaque PVT System without an Air Duct 221 6.3.2 A Roof-integrated Semi-transparent PVT System without an Air Duct 224 6.3.3 A Roof-integrated Opaque PVT System with an Air Duct 226 6.3.4 A Roof-integrated Semi-transparent PVT System with an Air Duct 230 6.3.5 Facade-integrated PVT Systems with and without a Duct 234 6.4 Overall Performance 234 6.4.1 Net Thermal Output 234 6.4.2 Net Exergy Output 235 6.5 A Case Study of a Roof-integrated PVT System with an Air Duct 236 6.5.1 System Description 236 6.5.2 Observations and Discussion 238 6.6 Optimization by Analyzing Different Configurations 245 6.6.1 Methodology for Analysis 246 6.6.2 Results and Discussion 247 6.7 Case Study of a Facade-integrated PVT System with an Air Duct 253 6.7.1 Thermal Modelling 253 6.7.2 Analysis of the System 255 6.7.3 Results and Discussion 256 6.8 Case Study with a -integrated PVT System 260 6.8.1 System Description 260 6.8.2 Thermal Modelling 262 6.8.3 Results and Discussion 265 6.9 Conclusions 266 References 266 XIV Chapter 7 Life Cycle Energy Analysis 268

7.1 Introduction 268 7.2 Embodied Energy 268 7.2.1 Process Analysis 269 7.2.2 InpubOutput Analysis 270 7.2.3 Hybrid Analysis 270 7.3 Life Cycle Metrics 271 7.3.1 Energy Payback Time 271 7.3.2 Electricity Production Factor 272 7.3.3 Life Cycle Conversion Efficiency 273 7.4 Greenhouse Gas Emissions 273 7.5 Energy Payback Time Studies for Photovoltaic Systems: A Literature Review 274 7.6 Energy Content Coefficient for Building Materials 275 7.7 Energy for Masonry Materials 278 7.7.1 Stone Blocks 278 7.7.2 Burnt Clay Bricks 279 7.7.3 Hollow Concrete Blocks 279 7.7.4 Soil-Cement Blocks 279 7.7.5 Steam Cured Mud Blocks 279 7.8 Energy in the Transportation of Building Materials 280 7.9 Energy in Mortars 281 7.10 Energy in Different Types of Masonry 281 7.11 Energy in Different Types of Floor and Roofing Systems 282 7.11.1 Stabilized Mud Block Filler Slab Roof 282 7.11.2 Composite Brick Panel Roof or Floor Slab 282 7.11.3 Reinforced Concrete Ribbed Slab Roof 283 7.11.4 Masonry Vault Roof 283 7.11.5 Ferroconcrete Tile Roof 283 7.12 Energy for Different Types of PV Modules 283 7.12.1 Energy for Silicon PV Modules 284 7.12.2 Energy for Non-silicon PV Modules 285 7.13 Energy for Balance of System 286 7.13.1 Charge Controller 287 7.13.2 Inverter 287 7.13.3 Batteries 287 7.14 Guidelines for Reducing Embodied Energy 288 7.15 Modelling of Embodied Energy for BIPVT Systems 289 7.15.1 Masonry Buildings 290 7.15.2 PVT Systems 290 7.15.3 Balance of System 291 7.16 A Case Study with a Roof-mounted BIPVT System 292 7.16.1 Assumptions 292 7.16.2 Components 292 Contents xv 7.16.3 Overall Embodied Energy and Energy Payback Time 294 References 296

Chapter 8 Carbon Dioxide Mitigation and Credit Earned 298 8.1 Introduction 298 8.2 The Carbon Cycle 300 8.3 The Kyoto Protocol and the UNFCCC 301 8.3.1 The Protocol and Green Growth 303 8.3.2 Emissions Trading and the CDM 304 8.3.3 Market Value and Volume of Transactions 305 8.3.4 CDM Successes to Date 306 8.3.5 The Post-2012 Climate Change Regime 306 8.3.6 United Nations Climate Change Conference at Copenhagen in 2009 307 8.3.7 Prospects 307 8.4 Earned Carbon Credit 308 8.4.1 Formulation 308 8.5 A Case Study with the BIPVT System 309 References 310

Chapter 9 Life Cycle Cost Assessments 311 9.1 Introduction 311 9.2 Estimating the Cost of a Project 311 9.2.1 Capital Costs 311 9.2.2 Variable Costs 312 9.2.3 Step-variable Costs 312 9.2.4 Non-product Costs 312 9.3 Depreciation 312 9.3.1 Straight-line Depreciation 312 9.3.2 Accelerated Depreciation 313 9.4 Interest 316 9.5 Cash Flow Diagram 319 9.6 Present or Future Value Calculations for a Regular Pattern of Cash Flows 320 9.6.1 Single Payment Future Value Factor 320 9.6.2 Single Payment Present Value Factor 324 9.6.3 Equal Payment Series Present Value Factor 326 9.6.4 Equal Payment Series Capital Recovery Factor 327 9.6.5 Equal Payment Series Future Value Factor 329 9.6.6 Equal Payment Series Sinking Fund Factor 332 9.6.7 Linear Gradient Series Present Value Factor 333 9.6.8 Gradient to Equal Payment Series Conversion Factor 335 9.6.9 Linear Gradient Series Future Value Factor 336 XVI Contents 9.7 Cost Comparison with Equal Duration 337 9.8 Cost Comparison with Unequal Duration 338 9.9 Cost Comparison using Capitalized Cost 341 9.10 Payback Period 342 9.11 Cost-Benefit Analysis 344 9.12 Internal Rate of Return 347 9.13 Cost Comparison after Taxes 351 9.14 Case Studies with BIPV and BIPVT Systems 354 9.14.1 Estimation of Cost 355 9.14.2 Modelling for Annualized Uniform Cost 356 9.14.3 Methodology 357 9.14.4 Results and Discussion 360 Further Reading 360

Appendix 361

Al Conversion of Units 361 A2 Average Annual Daily Ground Avail­ able During Clear Days on the Horizontal Surface 368 A3 Physical Properties of Metals and Non-metals 369 A4 Thermophysical Properties of Air and Saturated Water 373 A5 Absorptivity of Various Surfaces for the Sun's Rays 376 A6 Measured Radiation and Ambient Air Temperature at Srinagar (India) for Sample Calculations 378 A7 Embodied Energy Coefficients of Materials, PV Cells and Balance of Systems 385 A8 Lower and Higher Heating Values of Fuels 388 A9 Values of Conversion Factors at Different Worth Rates for Economic Analysis 389 A10 Further Resources: Websites 399

Glossary 400

Subject Index 417