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Most air-conditioned buildings in India operate as Mixed-Mode Buildings (MMBs), either fully air-conditioned or with natural ventilation depending on the weather. Energy consumption for space cooling is a vital end-use service in buildings. Air-conditioning is expected to increase significantly due to high growth estimates in building construction, sales of Room Air-Conditioners (RACs), and real income growth. Therefore, this thesis examines the most influential design and control parameters that influence the potential of MMBs in India in relation to their thermal and energy performance. The primary features of MMBs analysed in the research project are as follows: shutting windows at night makes night ventilation redundant; natural ventilation through ceiling fans and windows is utilised to maintain optimal thermal conditions in naturally-ventilated mode and RACs are employed in air-conditioned mode. This thesis poses three research questions and aims to answer them. Firstly, what are the research gaps in assessing thermal and energy performance in mixed-mode buildings in India? Secondly, what is their potential concerning key operating conditions, and which parameters affect this potential? Lastly, how can these influential parameters be optimised? To answer these questions, three research methods were employed: 1) literature review; 2) large-scale simulation of building energy performance combined with uncertainty and sensitivity analysis; and 3) field studies of user behaviour with regards to RACs and the impact of ceiling fans and RACs on indoor conditions and energy consumption. The study identifies the cooling set point temperature as the most influential control parameter. In general, input parameters related to building design, shape and geometry were considered more important than those related to construction parameters. Furthermore, the study highlights that a set point temperature of 28 or 30°C is sufficient to maintain indoor comfort according to the Indian Model for Adaptive Comfort (IMAC) for residential buildings. If a specific airflow is required, it would use the least energy to run the ceiling fan at a low speed, usually set at 1.
With increasing world population and an unsettling resource scarcity in the back, sustainble consumption has moved to the foreground of political, economical and social discussions. One major school-of-thought is Circular Economy (CE), an approach summarizing various sustainable consumption activites under one roof. However, quantitative studies on the consumer are rare, yet crucial for a transfer from linear to circular consumption. This dissertation adds to literature by providing pioneer insights into consumer behavior in CE as an overarching concept, instead limiting research on singular subconcepts. Namely, four consumer activities are studied: recycling, upcycling, renting and sharing. In order to identify relevant insights for both academics and practitioners in CE, the research question ("what drives participation in CE?") is broken down into sub-hypotheses, which are addressed by three empirical studies. Using the SOR-Model (adaption Belk 1975) as overarching logic, the three studies deal with (1) the consumer (and their motivation) and situational stimuli (both (2) offline and (3) online). Respectively, three data sets are consulted to assess the sub-hypotheses and to identify overarching insights on how to accelerate consumer participation in CE, The research methodology employed ranges from a structured equation model (SEM), a random allocation field experiment during Fashion Week in Berlin to a discrete-choice model with best-worst scaling. The dissertation succeeds in revealing that (1) different activities in CE can be summarized in one latent variable, proving CE as a wholesome concept in consumer-related activities; that (2) Trust has a leveraging effect on participation in CE activities. Further, Trust can be enhanced offline via face-to-face interaction and online via third-party online attributes.; and that (3) experience in CE activities affects perception of online attributes, implying the need for adapted measures when dealing with CE-unexperienced consumers as compared to consumers with prior experience in CE activities.
In this thesis, the systematic, situation-oriented selection of approaches to sustainability assessment and effects of selection on assessment results are investigated. The central focus lies on the practice-oriented design of a framework to support selection decisions as well as the necessary criteria and scales for the systematic, quantifiable description of assessment approaches and assessment situations within such a framework. Sustainability assessments are important instruments for the derivation of goals, strategies and measures for shaping sustainable development in all domains. They provide decision-makers in science, industry, politics and society with vital answers to sustainability-related questions that arise in the most diverse contexts. Numerous different assessment approaches are available for carrying out sustainability assessments within such assessment situations. Because of the multitude and diversity of assessment situations and approaches, not every approach is fitting for every situation. In current practice, the fit between approaches and assessment situations is not, or only insufficiently, taken into account when selecting sustainability assessment approaches. Furthermore, no systematic studies have yet been conducted on the effects of approach selection on assessment results. The central result of this work is a concept for the situation-oriented selection support of sustainability assessment approaches based on a Multi-Criteria Decision-Making framework. With the framework, "fitness scores" are calculated, which are used to quantify and operationalize the fit between assessment approaches and assessment situations. With the developed concept, different assessment approaches are selected and exemplarily applied within a use case. Hereby, the effects of approach selection on assessment results are examined. On the basis of the knowledge gained with regard to approach selection, framework development and application, the potentials and limits of assessment approaches widely fitting for diverse assessment situations are finally derived.
Climate change is a transformation challenge. It requires the transformation of a patchwork of independent socio-technical systems. These complex systems have their own specific challenges and path dependencies. Lukas Hermwille introduces a perspective on socio-technical complexity to the study of global climate governance and asks what governance arrangements on the international level, in particular the United Nations Framework Convention of Climate Change (UNFCCC) and its Paris Agreement, can offer to facilitate and foster the required transformational change. His work shows the importance of the discursive power of global climate governance, shifting the expectations and visions of the future of key actors and, as a corollary, changing their investment decisions of today towards a more sustainable future.
Since the middle of the 20th century, human society experiences a "Great Acceleration" manifesting in historically remarkable growth rates that create severe sustainability problems. The globally exploding potentials of information and knowledge exchange have been and are vital drivers for this acceleration. Society has now come to the point that it requires a "Great Transformation" towards sustainability to ensure the viability of the planet for a vital society. The energy transition plays a central role for this transformation. In this context, human society has developed a comparably good understanding of the necessary infrastructural changes of this transition. For transforming the patterns of energy production and use in an energy transition as part of the "Great Transformation", this process of change now needs to strengthen its focus on information, communication, and knowledge systems. Human society needs to establish a knowledge system that has the potential to create usable knowledge for sustainability solutions. This requires organizing a communication system that is sufficiently complex, interconnected, and, at the same time, efficient for integrating reflexive, open-ended, inter- and transdisciplinary learning, evaluation, and knowledge co-production processes across multiple levels. This challenge opens a wide field of research.
This cumulative dissertation contributes to research in this direction by applying a systemic sustainability perspective on the content and organization of communication in the field of research on sustainable energy and the operational level of municipal climate action as part of the energy transition. Regarding sustainability, this thesis uses strong sustainability and its principles as a frame for evaluating the content of communication. Regarding the systemic perspective, the thesis particularly relies on the following theories: (i) the human-environment system model by R. Scholz as an overarching framework regarding interactions between humans and nature, (ii) social systems theory by N. Luhmann to reflect the complexity of society, (iii) knowledge management to consider the human character of knowledge and a practice-oriented perspective, and (iv) management cybernetics, in particular, the Viable System Model by S. Beer as a framework to analyze and assess organizational structures. Furthermore, the thesis leverages the potential of text mining as a method to identify and visualize patterns in texts that reflect prevalent paradigms in communication.
The thesis applies the above conceptual and methodological basis in three case studies. Case Study 1 investigates the measures proposed in 16 municipal climate action plans of regional centers in Lower Saxony, Germany. It uses a text mining approach in the form of an Summary interpretation network analysis. It analyzes how different societal subsystems are connected at the semantic level and to what extent sustainability principles can be recognized. Case Study 2 analyzes and reflects paradigms and discursive network structures in international scientific publications on sustainable energy. The study investigates 26533 abstracts published from 1990 to 2016 using a text mining approach, in particular topic modeling via latent Dirichlet allocation. Case Study 3 turns again to the cases of municipal climate action in Lower Saxony examined in Case Study 1. It examines the involvement of climate action managers of these cities in multilevel knowledge processes. Using design principles for knowledge systems, it evaluates to what extent knowledge is managed in this field across levels for supporting the energy transition and to what extent local innovation potential is leveraged or supported.
The three case studies show that international research on sustainable energy and municipal climate action in Germany provide promising contributions to achieve a transformation towards sustainability but do not fully reflect the complexity of society and still support a growth paradigm, in contrast to a holistic sustainability paradigm. Further, the case studies show that research and local action are actively engaging with the diversity of energy technologies but are lagging in dealing with the socio-epistemic (communication) system, especially with regard to achieving cohesion. Using the example of German municipalities, Case Studies 1 and 3 highlight the challenges of achieving coherent local action for sustainability and bottom-up organizational learning due to incomplete or uncoordinated multilevel knowledge exchange. At the same time, the studies also point out opportunities for supporting the required coherent multilevel learning processes based on local knowledge. This can be achieved, for instance, by strengthening the coordinating role of intermediary organizational units or establishing closer interactions between the local operational units and the national level.
The thesis interprets and synthesizes the results of the three case studies from its systemic sustainability perspective. On this basis, it provides several generalized recommendations that should be followed for establishing viable communication systems, especially but not exclusively in policy-making:
Systemic holism: Consider matter, energy, and information flows as an integrated triplet in the context of scales, structures, and time in the various subsystems. Knowledge society: Focus on the socio-epistemic (communication) system, e.g., using the perspective of knowledge systems and associated design principles considering, for instance, working environments across horizontal and vertical levels, knowledge forms and types, and knowledge processes. Sufficiency communication: Emphasize sufficiency approaches, make it attractive, and find differentiated ways for communicating them. Multilevel cohesion and innovation: Achieve cohesion between the local and higher levels and leverage local innovations while avoiding isolated local action. Organizational interface design: Define the role of organizational units by the interactions they create at the interfaces with and between societal subsystems. Local transdisciplinarity: Support local transdisciplinary approaches integrating various subsystems, especially industry, while coordinating these approaches from a higher level for leveraging local innovation. Digital public system: Exploit existing digital technologies or infrastructures in the public system and recognize the value of data in the public sphere for achieving cohesion. Beyond the above recommendations, this thesis suggests that potential for further research lies in: Advancing nature-inspired systemic frameworks. Understanding the structure and creation of human knowledge. Developing text mining methodologies towards solution-oriented approaches.
Social business innovations
(2018)
This research project approached the emergence of social business innovations from the periphery, working towards the core: the first article features the representation of the concept of Social Business City, which was newly implemented by Wiesbaden in 2010. Here, social businesses are to be founded with the help of a network based on both public and private institutions. At the time of conducting the research, three such Social Business Cities existed: Wiesbaden (Germany), Fukuoka (Japan) and Pistoia (Italy); in 2016 Barcelona joined the list of Social Business Cities. The second article analyses the ways in which microfinance organisations that are based on the concept of social business according to Yunus differ from one another. Included in this research was Grameen Bank in Bangladesh, Social Business Women in Germany and Grameen America in the United States. Subsequently, a third article investigates the similarities and differences to be found between social businesses and charities. The research focuses on advantages and disadvantages on both sides and aims at answering the questions: which approach is appropriate under what circumstances and which aspects could be adopted by the other?
Finally, we investigated the various cooperation of the Grameen Group with global players such as Danone, Veolia and Intel in Bangladesh and the particular challenges which result therefrom.
The earth as we know it can only continue to exist if humanity finds a way to switch to a sustainable use of energy and resources. This work contributes to the research carried out to achieve this goal by improving the coating of adsorptive materials. These are used in heat transformation and drying processes that allow for efficient temperature and humidity control in buildings. A central component of these adsorptive coatings is the binder that acts as "glue" in the manufacturing of the coating. In this work the methods to evaluate binder performance regarding their thermal stability under the process conditions, their mechanical stability and their influence on the adsorptive properties of the coating were established. The coatings have to meet special requirements due to the thermal stresses and low pressure atmosphere they experience in these applications. A selection of silicone binders was then characterized with the established tests according to these requirements. Additionally a selection of inorganic binders was investigated because they allow for the use of high desorption temperatures and thus a high energy efficiency of the process. Out of these binders Silres® MP50E emerged as the most promising one due to very good adsorptive properties of the coating, its good temperature stability and ease of use. While some of the inorganic binders showed very good adsorptive properties and temperature stability the mechanical stability of all inorganic binders was not sufficient for their use in adsorption heat transformation technology. This is the first time that a broad selection of binders was evaluated with regards to adsorptive coatings and the results published in literature. With a suitable binder identified, the next step was to optimize the coating of the heat exchangers in order to work out how to manufacture the most efficient and powerful heat exchangers. Samples with different coating thicknesses were manufactured in small scale and full scale and their adsorption behavior was characterized. It could be shown for the first time that it is possible to increase energy efficiency by improving the mass ration of adsorber to coating and increase the delivered power at the same time. This was shown for small and full scale samples. It was shown that under the corresponding conditions the heat transfer from the coating layer to the adsorber metal substrate is the limiting step in the process. These results can now be used for the planning and construction of adsorbers. With knowledge of a suitable binder and how to coat efficient, powerful adsorbers, the coating process itself was improved to allow for industrial scale manufacturing. A central point here is the ability to control slurry rheology. Out of many rheology additives those that are suited for the application in adsorption heat transformation were identified and their influence on the slurry rheology thoroughly characterized. Additionally the process of slurry preparation could be simplified for several different adsorbents. Here it was shown that the supersonic deagglomeration step is not necessary to prepare a slurry. Extending the possible coating techniques and in addition to the dip coating process used so far, the spray coating of adsorptive coatings was established for the first time in literature. This process is widely used in the industry and allows for easier plugin into existing coating processes. For the coating of high resolution patterns a proof of concept of the screen printing process was carried out.
Enhancing cross-functional integration in new product development becomes increasingly important for industrial players to keep up with shorter product life cycles in technological innovation dynamics. Abundant research reflects the topic's significance, yet ambiguity in empirical results persists and industrial adoption of existing methods remains incremental. This thesis employs a qualitative approach to build a case study at the design-manufacturing interface of new product development of electrified cars. Cross-functional coopetition, as the joint occurrence of cooperation and competition, is adopted to generate an in-depth understanding of integration dynamics. Socio-organizational and contextual aspects are found to shape integration in a new product development context substantially. A model of interface dynamics is developed which provides for analysis and prediction of these aspects' impact on effective integration. A grounded theory approach to enhance integration is explored that introduces constraints as stimuli to consider manufacturability aspects in the design process. Constraint introduction is found to positively impact both cross-functional integration and creativity, with eight characteristics of constraint quality identified as moderating factors. A theoretical model is contributed which outlines cause-effect relationships of constraints' impact on antecedents of new product development success. It substantiates constraints' role in innovation contexts and encourages application for design-manufacturing integration as well as for other interfaces or purposes.
This doctoral research is located in the branch of sustainability sciences that has the realisation of sustainable development as its core subject of research. The most broadly accepted notion of sustainable development is that which evolves along the resolutions, declarations, and reports from international processes in the framework of the United Nations (UN). The consensual outputs from such processes feature global-generalised and context-free perspectives. However, implementation requires action at diverse and context-rich local levels as well. Moreover, while in such UN processes national states are the only contractual parties, it is increasingly recognised that other ("nonstate") actors are crucial to sustainability. The research presented here places the attention on bottom-up initiatives that are advancing innovative ways to tackle universal access to clean energy and to strengthen small-scale family farmers. This means, the focus is on bottom-up initiatives advancing local implementation of global sustainability targets, more precisely, targets that make part of the Sustainable Development Goals two and seven (SDG 2 and SDG7). The research asks how such bottom-up initiatives can contribute to the diffusion of sustainability innovations, thereby also contributing to social change.
The transformation of cities towards sustainable and inclusive development is a key objective of the New Urban Agenda (United Nations 2017). Transport infrastructure is a critical factor in shaping cities, determining the energy intensity of mobility and providing access to essential social and economic opportunities. The sector also plays an important role in global climate change mitigation strategies, as it currently accounts for about 23% of global energy-related greenhouse gas emissions (IPCC 2014).
There is substantial potential to improve urban access, air quality, safety and the quality of life in cities along with reducing Greenhouse Gas Emissions if an integrated policy approach is applied that combines all intervention areas for transport policy and involves all levels of government. A package that achieves low-carbon transport and fosters sustainable developed includes avoided journeys through compact urban design and shifts to more efficient modes of transport, uptake of improved vehicle and engine performance technologies, low-carbon fuels, investments in related infrastructure, and changes in the built environment. From a governance perspective, all relevant political institutions at the local and national level need to be involved in the coalition building along with key societal actors, such as unions, industry and civil society organisations. Bringing the policy objectives of these actors together with an integrated policy package is a vital step towards a low-carbon, sustainable mobility system.
Policy design and governance are critically interlinked as the ability of institutions to find a political consensus and to maintain policy stability heavily influences the success of measures to shape the transformation pathway towards sustainable mobility. This thesis aims to analyse these linkages and highlight the role of different policy and governance approaches. This analysis builds on transport and urban development research, but takes a transdisciplinary research perspective, building on the Multi-Level-Perspective on sustainability transitions (Geels 2002) and aims to highlight the potential for a consensus oriented policy approach (Lijphard 1999) that builds on co-benefits among key policy objectives and coalitions among key political actors, which leads to the main question for this thesis and the focus areas for the analysis.