Building energy design is currently going through a period of major changes. One key factor of this is the adoption of net-zero energy as a long term goal for new buildings in most developed countries. To achieve this goal a lot of research is needed to accumulate knowledge and to utilize it in practical applications. In this book, accomplished international experts present advanced modeling techniques as well as in-depth case studies in order to aid designers in optimally using simulation tools for net-zero energy building design. The strategies and technologies discussed in this book are, however, also applicable for the design of energy-plus buildings. This book was facilitated by International Energy Agency's Solar Heating and Cooling (SHC) Programs and the Energy in Buildings and Communities (EBC) Programs through the joint SHC Task 40/EBC Annex 52: Towards Net Zero Energy Solar Buildings R&D collaboration.
After presenting the fundamental concepts, design strategies, and technologies required to achieve net-zero energy in buildings, the book discusses different design processes and tools to support the design of net-zero energy buildings (NZEBs). A substantial chapter reports on four diverse NZEBs that have been operating for at least two years. These case studies are extremely high quality because they all have high resolution measured data and the authors were intimately involved in all of them from conception to operating. By comparing the projections made using the respective design tools with the actual performance data, successful (and unsuccessful) design techniques and processes, design and simulation tools, and technologies are identified.
Written by both academics and practitioners (building designers) and by North Americans as well as Europeans, this book provides a very broad perspective. It includes a detailed description of design processes and a list of appropriate tools for each design phase, plus methods for parametric analysis and mathematical optimization. It is a guideline for building designers that draws from both the profound theoretical background and the vast practical experience of the authors.
Modeling, Design, and Optimization of Net-Zero Energy Buildings
Description
Table of Contents
About the editors xiii List of contributors xv
Preface xvii
Foreword xix
Acknowledgments xxi
1 Introduction 1
1.1 Evolution to net-zero energy buildings 1
1.1.1 Net ZEB concepts 2
1.1.2 Design of smart Net ZEBs and modeling issues 4
1.2 Scope of this book 4
References 7
2 Modeling and design of Net ZEBs as integrated energy systems 9
2.1 Introduction 9
2.1.1 Passive design, energy efficiency, thermal dynamics, and comfort 10
2.1.2 Detailed frequency domain wall model and transfer functions 16
2.1.2.1 Distributed parameter model for multilayered wall 16
2.1.2.2 Admittance transfer functions for walls 17
2.1.3 Z-Transfer function method 22
2.1.4 Detailed zone model and building transfer functions 25
2.1.4.1 Analysis of building transfer functions 30
2.1.4.2 Heating/cooling load and room temperature calculation 32
2.1.4.3 Discrete Fourier Series (DFS) method for simulation 32
2.1.5 Building transient response analysis 33
2.1.5.1 Nomenclature 34
2.2 Renewable energy generation systems/technologies integrated in Net ZEBs 34
2.2.1 Building-integrated photovoltaics as an enabling technology for Net ZEBs 35
2.2.1.1 Technologies 36
2.2.1.2 Modeling 39
2.2.2 Solar thermal systems 45
2.2.2.1 Solar thermal collectors 45
2.2.2.2 Modeling of solar thermal collectors 49
2.2.2.3 Thermal storage tanks 51
2.2.2.4 Modeling of thermal storage tanks 52
2.2.2.5 Solar combi-systems 55
2.2.3 Active building-integrated thermal energy storage and panel/radiant heating/cooling systems 55
2.2.3.1 Radiant heating/cooling systems integrated with thermal mass 57
2.2.3.2 Modeling active BITES 58
2.2.3.3 Methods used in two mainstream building simulation software 62
2.2.3.4 Nomenclature 63
2.2.4 Heat pump systems - a promising technology for Net ZEBs 63
2.2.4.1 Solar air-conditioning 64
2.2.4.2 Solar assisted/source heat pump systems 64
2.2.4.3 Ground source heat pumps 65
2.2.5 Combined heat and power (CHP) for Net ZEBs 66
References 67
3 Comfort considerations in Net ZEBs: theory and design 75
3.1 Introduction 75
3.2 Thermal comfort 76
3.2.1 Explicit thermal comfort objectives in Net ZEBs 77
3.2.2 Principles of thermal comfort 77
3.2.2.1 A comfort model based on the heat-balance of the human body 78
3.2.2.2 The adaptive comfort models 83
3.2.2.3 Standards regarding thermal comfort 85
3.2.3 Long-term evaluation of thermal discomfort in buildings 87
3.2.3.1 Background 88
3.2.3.2 The likelihood of dissatisfied 89
3.2.3.3 Applications of the long-term (thermal) discomfort indices 91
3.3 Daylight and visual comfort 92
3.3.1 Introduction 92
3.3.2 Adaptation luminance 94
3.3.3 Illuminance-based performance metrics 95
3.3.3.1 Daylight autonomy and continuous daylight autonomy 95
3.3.3.2 Useful daylight illuminance 95
3.3.4 Luminance-based performance metrics 96
3.3.4.1 Daylight glare probability 96
3.3.5 Daylight and occupant behavior 97
3.4 Acoustic comfort 98
3.5 Indoor air quality 99
3.6 Conclusion 100
References 101
4 Net ZEB design processes and tools 107
4.1 Introduction 107
4.2 Integrating modeling tools in the Net ZEB design process 108
4.2.1 Introduction 108
4.2.2 Overview of phases in Net ZEB realization 108
4.2.3 Tools 111
4.2.4 Concept design 112
4.2.4.1 Daylight 113
4.2.4.2 Solar protection 114
4.2.4.3 Building thermal inertia 115
4.2.4.4 Natural and hybrid ventilation 116
4.2.4.5 Building envelope thermal resistance 118
4.2.4.6 Solar energy technologies integration 119
4.2.5 Design development 119
4.2.5.1 Envelope and thermal inertia 120
4.2.5.2 Daylight 120
4.2.5.3 Plug loads and electric lighting 122
4.2.5.4 RET and HVAC 123
4.2.6 Technical design 124
4.2.7 Integrated design process and project delivery methods 126
4.2.8 Conclusion 133
4.3 NET ZEB design tools, model resolution, and design methods 133
4.3.1 Introduction 133
4.3.2 Model resolution 134
4.3.3 Model resolution for specific building systems and aspects 141
4.3.3.1 Geometry and thermal zoning 141
4.3.3.2 HVAC and active renewable energy systems 144
4.3.3.3 Photovoltaics and building-integrated photovoltaics 145
4.3.3.4 Lighting and daylighting 147
4.3.3.5 Airflow 149
4.3.3.6 Occupant comfort 151
4.3.3.7 Occupant behavior 153
4.3.4 Use of tools in design 157
4.3.4.1 Climate analysis 157
4.3.4.2 Solar design days 159
4.3.4.3 Parametric analysis 160
4.3.4.4 Interactions 161
4.3.4.5 Multidimensional parametric analysis 162
4.3.4.6 Visualization 162
4.3.5 Future needs and conclusion 163
4.4 Conclusion 165
References 166
5 Building performance optimization of net zero-energy buildings 175
5.1 Introduction 175
5.1.1 What is BPO? 175
5.1.2 Importance of BPO in Net ZEB design 176
5.2 Optimization fundamentals 179
5.2.1 BPO objectives (single-objective and multi-objective functions) 179
5.2.2 Optimization problem definition 180
5.2.3 Review of optimization algorithms applicable to BPS 180
5.2.4 Integration of optimization algorithms with BPS 183
5.2.5 BPO experts interview 184
5.3 Application of optimization: cost-optimal and nearly zero-energy building 186
5.3.1 Introduction 186
5.3.2 Case study: single-family house in Finland 188
5.3.3 Results 190
5.3.4 Final considerations about the case study 194
5.4 Application of optimization: a comfortable net-zero energy house 195
5.4.1 Description of the building model 195
5.4.2 The adopted methodology and the statement of the optimization problem 196
5.4.3 Discussion of results 199
5.4.4 Final considerations 202
5.5 Conclusion 202
References 203
6 Load matching, grid interaction, and advanced control 207
6.1 Introduction 207
6.1.1 Beyond annual energy balance 207
6.1.2 Relevance of LMGI issues 207
6.1.2.1 Peak demand and peak power generation 207
6.1.2.2 Load management in the grid and buildings 209
6.1.2.3 Smart grid and other technology drivers 211
6.2 LMGI indicators 212
6.2.1 Introduction 212
6.2.2 Categories of indicators 215
6.3 Strategies for predictive control and load management 219
6.3.1 Energy storage devices 219
6.3.1.1 Electric energy storage 219
6.3.1.2 Thermal energy storage 220
6.3.2 Predictive control for buildings 220
6.3.2.1 Preliminary steps 222
6.3.2.2 Requirements of building models for control applications 223
6.3.2.3 Modeling of noncontrollable inputs 225
6.3.2.4 Development of a control strategy 226
6.4 Development of models for controls 226
6.4.1 Building components: conduction heat transfer 227
6.4.2 Thermal modeling of an entire building 227
6.4.3 Linear models 228
6.4.3.1 Continuous-time transfer functions 228
6.4.3.2 Discrete-time transfer functions (z-transforms transfer functions) 229
6.4.3.3 Time series models 231
6.4.3.4 State-space representation 232
6.5 Conclusion 235
References 236
7 Net ZEB case studies 241
7.1 Introduction 241
7.2 EcoTerra 243
7.2.1 Description of EcoTerra 243
7.2.2 Design process 252
7.2.2.1 Design objectives 252
7.2.2.2 Design team and design process 252
7.2.2.3 Use of design and analysis tools 253
7.2.2.4 Assessment of the design process 255
7.2.3 Measured performance 256
7.2.4 Redesign study 259
7.2.4.1 Boundary conditions 260
7.2.4.2 Form and fabric 260
7.2.4.3 Operations 260
7.2.4.4 Renewable energy systems 261
7.2.4.5 Simulation results 261
7.2.4.6 Implementation of redesign strategies 262
7.2.5 Conclusions and lessons learned 266
7.3 Leaf house 269
7.3.1 Main features of the leaf house 269
7.3.2 Description of the design process 272
7.3.3 Purposes of the building design 272
7.3.4 Description of the thermal system plant 272
7.3.5 Monitored data 277
7.3.6 Features and limits of the employed model 278
7.3.7 Calibration of the model 280
7.3.8 Redesign 284
7.3.9 Conclusions and lessons learned 288
7.4 NREL RSF 289
7.4.1 Introduction to the RSF 290
7.4.2 Key project design features 291
7.4.2.1 Design process 291
7.4.2.2 Envelope 292
7.4.2.3 Daylighting and electric lighting 293
7.4.2.4 Space conditioning system 293
7.4.2.5 Thermal storage labyrinth 295
7.4.2.6 Transpired solar thermal collector 297
7.4.2.7 Natural ventilation 298
7.4.2.8 Building operation, typical monitored data, and thermal performance 298
7.4.2.9 Photovoltaics 301
7.4.2.10 Building simulation software support 302
7.4.2.11 Software limitations 303
7.4.2.12 Significance of the early design stage 304
7.4.3 Abstraction to archetypes 306
7.4.3.1 Model development 307
7.4.3.2 Model validation and calibration 311
7.4.3.3 Integrating design and control for daylighting and solar heat gain - option with controlled shading 312
7.4.4 Alternative design and operation for consideration 319
7.4.4.1 Building-integrated PV: optimal use of building roof and facade 319
7.4.4.2 Building-integrated PV/T and transpired collector with air-source heat pump 319
7.4.4.3 Active building-integrated thermal energy storage 320
7.4.5 Conclusions. 320
7.5 ENERPOS 321
7.5.1 Natural cross-ventilation and ceiling fans 322
7.5.2 Solar shading and daylighting 323
7.5.3 Microclimate measures 323
7.5.4 Materials 324
7.5.5 Ergonomics and interior design 324
7.5.6 Energy efficiency 325
7.5.6.1 Artificial lighting 325
7.5.6.2 Ceiling fans 325
7.5.6.3 Air-conditioning system 326
7.5.6.4 Computer network and plug loads 326
7.5.6.5 Building management system and individual controls 326
7.5.7 Integration of renewable energy technology 327
7.5.8 Description of the design process 327
7.5.8.1 Design objectives and importance of the design brief 328
7.5.8.2 Design team and timeline 328
7.5.8.3 Design tools 328
7.5.8.4 Human factors consideration in the design 330
7.5.9 Monitoring system 331
7.5.10 Monitored data 331
7.5.10.1 Measured performance 331
7.5.11 Comparison of model prediction with measurements for ENERPOS 333
7.5.11.1 Energy use 333
7.5.11.2 Thermal comfort 336
7.5.12 Thermal comfort experimental study 338
7.5.12.1 Purpose and methodology 338
7.5.12.2 Main results of the surveys 339
7.5.12.3 A comparison between the experimental data and the Givoni comfort zones 339
7.5.13 Lessons learned for future design of Net ZEBs in tropical climate 341
7.5.13.1 Interior lighting 342
7.5.13.2 Elevator energy 343
7.5.13.3 Air-conditioning 343
7.5.13.4 Occupant behavior 343
7.5.13.5 Use of building thermal mass and night cooling 343
7.6 Conclusions 343
References 345
8 Conclusion, research needs, and future directions 351
8.1 Net ZEB modeling, design, and simulation 351
8.2 Future directions and research needs 352
Glossary 355
Index 361
Author Description
Review quote
"The editors have done an admirable job collecting and compiling these materials and this book respresents the current thinking on Net ZEB building and design." (3D Visualization World Magazine, 24 June 2015)