Preface

Urban transitions are important because society today faces several different challenges, such as climate change, increased population, extreme weather events, environmental degradation, and the risk of collapsing ecosystems. To combat these challenges scientists and global leaders have called for a transition towards a more environmental society. Ideally, a society with urban environments and systems that are climate-positive, sustainable, and healthy and make the society function within the planetary boundaries. This is a great challenge. Huge transformations and new ways of thinking regarding the design and co-existence of technical, social, and ecological systems are necessary to turn the present challenge into opportunities. This book explores this challenge and several different topics related to possible, probable, or necessary urban transitions in the urban environment. It assembles a variety of aspects and the latest knowledge linked to urban transitions of the urban environment and the urban socio-eco-technological systems including urban, energy, transport, building, material, and ecosystems. Different systems that are responsible for a large proportion of the use of natural resources and energy, and the production of waste and emissions, also have a large influence on many areas of human life and wellbeing. These systems create value for many people, but often this value comes at a high environmental cost. Their complexity makes it difficult to evaluate and validate their impact on the surroundings. Therefore, it is a challenge to know how to plan, design, and influence these systems in an optimal way. It is important to find solutions for urban transitions, to navigate transitions in suitable ways, and to capture the innovation opportunities that come with them. This book proposes ideas to provoke and develop current research, debate, and new forms of practice. To reflect the broad context that urban transition concerns, the chapter authors discuss some of the many important urban transition aspects to consider when designing, making decisions, and constructing our future urban environments and working with solutions for a sustainable and resilient urban transition in society. The perspectives in the book vary from the importance of urban designing and the outdoor environment to the importance of indoor air quality, highlighting many aspects that are important for creating a good living environment. Because of the complexity of creating such an environment, it is necessary for researchers and professionals from different fields to plan and act strategically.

Many of the book chapters concern topics that researchers at the University of Gävle, Sweden, are studying. The university has a long history of studying the built environment. Today, the university's research is internationally renowned in sustainability science, energy systems, ecology, and urban sustainability. For example, the university has a strategic research area in Urban Sustainability which holds the research program Urban Transition where both Wallhagen and Cehlin are active. There is also an increased number of active Ph.D. students within the research school "Future Proof Cities" and the competence center "Resilient" at the university working with co-creation and urban transition towards a more sustainable society.

Section 1 is on "Urban Design, Transport, Safety, and Envisioning the Future – Influence on Urban Transitions". Chapter 1 by Johan Colding et al. is about "Promoting Partnership between Urban Design and Urban Ecology through Social-Ecological Resilience Building". It highlights the importance of a closer partnership between urban design and urban ecology. The authors show that if social-ecological resilience is used as a framework, it can open new ways of integrating design and ecology in urban planning. Chapter 2, "Sustainable Transport Developments for Dhaka City", by Md Mahabubul Bari, examines the consequences traditional traffic planning can have on mobility in a city like Dhaka. It reminds us about the importance of not getting trapped in only thinking about motor vehicles when considering mobility in a city, especially in a city like Dhaka where a lot of transports are pedestrian transports. Chapter 3, "Inclusive, Safe and Resilient Public Spaces: Gateway to Sustainable Cities?", by Asifa Iqbal, reviews how a city's public spaces are linked and affected by crime and fear of crime. Promoting positive urban transitions also includes creating safe and sustainable cities. Therefore, the built environment should be designed to prevent crime and fear of crime. Chapter 4, "Future Urban Environments in Science Fiction: Initiated Thought Experiments", by Britt Johanne Farstad, examines the important role science fiction literature has on the transformation of our visions and ideas about future cities. Ideas and the impact of science and technology on society, culture, and ethics can be tested and elaborated on in hypothetical thought experiments. This may help us fantasize and envision what future cities should look like and encourage us to explore transformations we today believe are impossible as well as challenge present ideas about the human condition.

Section 2, "Sustainable Energy Systems – Enable Urban Transitions", addresses the important role energy plays in the transformation towards a more resilient and sustainable society. Chapter 5, "Review on District Cooling and Its Application in Energy Systems" by Sana Sayadi et al., highlights benefits and limitations as well as implementations and applications of energy systems. District cooling systems are resourceefficient and can play an important role in meeting future cooling demands due to climate changes and the increase in comfort requirements in buildings. Chapter 6, "Photovoltaic-Thermal Solar Collectors – A Rising Solar Technology for an Urban Sustainable Development", by Diogo O. Cabral, explores the prospective contribution of photovoltaic-thermal (PVT) solar collector technologies in promoting urban sustainability. It underscores the need for rigorous and systematic decarbonization in the energy sector, where PVT technologies should be considered. Chapter 7, "Energy Audit of Two Multifamily Buildings and Economic Evaluation of Possible Improvements", by Alireza Bahrami et al., emphasizes the potential to enhance energy efficiency in our buildings, which is crucial for reaching the EU's carbon-neutrality target by 2050.

Section 3, "Resilient and Environmental Buildings – Central for Urban Transitions", discusses several issues relevant to the urban transitioning of buildings. Buildings use lots of energy and natural resources, contribute to waste, and influence our local environment and well-being, as most of our lives are spent indoors. In Chapter 8, "Viewpoints on Environmental Assessment of Building Certification Method – Miljöbyggnad", Jan Akander et al. discuss several aspects that the Swedish building environmental assessment tool Miljöbyggnad assesses. They also highlight improvements in measuring how environmental a building is, especially when the climate is changing. Climate change consequences are discussed further in Chapter 9, "Climate Change and Extreme Wind Events: Overview and Perspectives for a Resilient Built Environment", by Sofia Pastori and Enrico Sergio Mazzucchelli. The chapter clarifies that the increase in extreme wind events makes it necessary to prepare buildings for more extreme wind events when building resilience.

**V**

Section 4, "Sustainable Ventilation – Give Air to Urban Transitions", examines the importance of providing good air quality for human well-being in both new and existing buildings and in open spaces. The World Health Organization (WHO) has proposed that every individual's right to a healthy indoor setting should be considered a fundamental human right. Hence, proper ventilation is central to achieving this goal. Chapter 10, "Building for Sustainable Ventilation and Air Quality", by Mikael Björling, addresses the importance of not only ventilation rates but also efficient air distribution for achieving a healthy and comfortable indoor environment. This is also discussed in Chapter 11, "Some Aspects of HVAC Design in Energy Renovation of Buildings", by Taghi Karimipanah. This chapter discusses the design of efficient air distribution systems for improving the energy efficiency of buildings, but not at the expense of deteriorating indoor comfort and indoor air quality. Finally, Chapter 12, "Post Covid 19: An Innovative System to Supply 100% Treated Fresh Air for Improving City Liveability", by Esam Elsarrag and Mohammad Elsarraj, presents an all-in-one ventilating and air conditioning system for use in both open and enclosed spaces. The authors discuss drivers, challenges, and the technology to provide efficient treated fresh air whilst

reducing energy consumption, especially for hot and/or humid climates.

when creating a more just, sustainable, and resilient urban transition.

Although the focus of this book is mainly on socio-technical systems, it is important to acknowledge the link between socio-technical systems and ecological systems. If we have an environmental perspective and a lifecycle perspective on the socio-technical systems, the ecological systems are always present, as the geobiosphere is affected by socio-technical activities. Finding ways for them to co-exist in a more beneficial way, for example by using more nature-based solutions, is another important aspect

The work with this book and in our research program on "Urban Transition" at the University of Gävle has made us look for a definition of what constitutes a sustainable environmental and resilient urban transition. At this moment urban transition can be specified as "a goal-driven strategic transition towards a sustainable, attractive, and just built environment and society through comprehensive changes in technical, ecological, and socio-technical systems. It encompasses systems, artifacts, and ecosystems connected to the built environment as well as processes and people. The main goal is to solve environmental and societal challenges by promoting resilient, resource-efficient, and circular systems that improve the human living environment."

We look forward to following the essential urban transition in the built environment and we wish to thank all the authors for their valuable contributions to the book.

**Marita Wallhagen, Ph.D. and Mathias Cehlin, Ph.D.**

Department of Building Engineering, Energy Systems and Sustainability Science,

Associate Professor,

University of Gävle, Gävle, Sweden Section 4, "Sustainable Ventilation – Give Air to Urban Transitions", examines the importance of providing good air quality for human well-being in both new and existing buildings and in open spaces. The World Health Organization (WHO) has proposed that every individual's right to a healthy indoor setting should be considered a fundamental human right. Hence, proper ventilation is central to achieving this goal. Chapter 10, "Building for Sustainable Ventilation and Air Quality", by Mikael Björling, addresses the importance of not only ventilation rates but also efficient air distribution for achieving a healthy and comfortable indoor environment. This is also discussed in Chapter 11, "Some Aspects of HVAC Design in Energy Renovation of Buildings", by Taghi Karimipanah. This chapter discusses the design of efficient air distribution systems for improving the energy efficiency of buildings, but not at the expense of deteriorating indoor comfort and indoor air quality. Finally, Chapter 12, "Post Covid 19: An Innovative System to Supply 100% Treated Fresh Air for Improving City Liveability", by Esam Elsarrag and Mohammad Elsarraj, presents an all-in-one ventilating and air conditioning system for use in both open and enclosed spaces. The authors discuss drivers, challenges, and the technology to provide efficient treated fresh air whilst reducing energy consumption, especially for hot and/or humid climates.

Although the focus of this book is mainly on socio-technical systems, it is important to acknowledge the link between socio-technical systems and ecological systems. If we have an environmental perspective and a lifecycle perspective on the socio-technical systems, the ecological systems are always present, as the geobiosphere is affected by socio-technical activities. Finding ways for them to co-exist in a more beneficial way, for example by using more nature-based solutions, is another important aspect when creating a more just, sustainable, and resilient urban transition.

The work with this book and in our research program on "Urban Transition" at the University of Gävle has made us look for a definition of what constitutes a sustainable environmental and resilient urban transition. At this moment urban transition can be specified as "a goal-driven strategic transition towards a sustainable, attractive, and just built environment and society through comprehensive changes in technical, ecological, and socio-technical systems. It encompasses systems, artifacts, and ecosystems connected to the built environment as well as processes and people. The main goal is to solve environmental and societal challenges by promoting resilient, resource-efficient, and circular systems that improve the human living environment."

We look forward to following the essential urban transition in the built environment and we wish to thank all the authors for their valuable contributions to the book.

> **Marita Wallhagen, Ph.D. and Mathias Cehlin, Ph.D.** Associate Professor, Department of Building Engineering, Energy Systems and Sustainability Science, University of Gävle, Gävle, Sweden

**1**

Section 1

Urban Design, Transport,

Safety, and Envisioning the

Future – Influence on Urban

Transitions

### Section 1
