Open Access

Many cities all over the world highlight the need to transform their urban mobility systems into more sustainable ones, to confront pressing issues such as air and noise pollution, and to deliver on climate change mitigation action. While the support of innovations is high on the agenda of both national and local authorities, consciously phasing-out unsustainable technologies and practices is often neglected. However, this other side of the policy coin, "exnovation", is a crucial element for the mobility transition. We developed a framework to facilitate a more comprehensive assessment of urban mobility transition policies, systematically integrating exnovation policies. It links exnovation functions as identified in transition studies with insights from urban mobility studies and empirical findings from eight city case studies around the world. The findings suggest that most cities use some kinds of exnovation policies to address selective urban mobility issues, e.g., phasing-out diesel buses, restricting the use of polluting motor vehicles in some parts of the city, etc. Still, we found no evidence for a systematic exnovation approach alongside the innovation policies. Our framework specifies exnovation functions for the urban mobility transition by lining out policy levers and concrete measure examples. We hope that the framework inspires future in-depth research, but also political action to advance the urban mobility transition.

This paper presents an approach for assessing lifestyle carbon footprints and lifestyle change options aimed at achieving the 1.5 °C climate goal and facilitating the transition to decarbonized lifestyles through stakeholder participatory research. Using data on Finland and Japan it shows potential impacts of reducing carbon footprints through changes in lifestyles for around 30 options covering food, housing, and mobility domains, in comparison with the 2030 and 2050 per-capita targets (2.5-3.2 tCO2e by 2030; 0.7-1.4 tCO2e by 2050). It discusses research opportunities for expanding the footprint-based quantitative analysis to incorporate subnational analysis, living lab, and scenario development aiming at advancing sustainability science on the transition to decarbonized lifestyles.

Energy sufficiency is one of the three energy sustainability strategies, next to energy efficiency and renewable energies. We analyse to what extent European governments follow this strategy, by conducting a systematic document analysis of all available European National Energy and Climate Plans (NECPs) and Long-Term Strategies (LTSs). We collect and categorise a total of 230 sufficiency-related policy measures, finding large differences between countries. We find most sufficiency policies in the transport sector, when classifying also modal shift policies to change the service quality of transport as sufficiency policies. Types of sufficiency policy instruments vary considerably from sector to sector, for instance the focus on financial incentives and fiscal instruments in the mobility sector, information in the building sector, and financial incentive/tax instruments in cross-sectoral application. Regulatory instruments currently play a minor role for sufficiency policy in the national energy and climate plans of EU member states. Similar to energy efficiency in recent decades, sufficiency still largely referred to as micro-level individual behaviour change or necessary exogenous trends that will need to take place. It is not treated yet as a genuine field of policy action to provide the necessary framework for enabling societal change.

Damit sich die weltweit zunehmend ambitionierten Klimaschutzziele erreichen lassen, müssen auch im Industriesektor weitgehende Emissionsreduktionen innerhalb weniger Jahrzehnte realisiert werden. Expertinnen und Experten sind sich einig, dass dies nicht ohne den Umstieg von fossilen auf erneuerbare Energieträger und Rohmaterialien - sogenannte Feedstocks - umsetzbar ist. Im Zuge der verstärkten Nutzung dieser grünen Energieträger ist denkbar, dass sich deren Verfügbarkeit und Kosten zu immer wichtigeren Standortfaktoren für die Produktion industrieller Güter entwickeln werden. Dies könnte dazu führen, dass zukünftig Standorte mit kostengünstiger Verfügbarkeit von erneuerbaren Energien attraktiver gegenüber anderen Standorten werden und es dann zu Standortverlagerungen kommt - insbesondere im Bereich der energieintensiven Industrie. In dem vorliegenden Artikel greifen die Autoren diese möglichen Verlagerungen industrieller Produktion auf. In diesem Zusammenhang führen sie auch den Begriff "Renewables Pull" ein. Die in bestimmten Regionen der Welt kostengünstig und in großen Mengen verfügbaren erneuerbaren Energien könnten nach Ansicht der Autoren künftig eine Sogwirkung auslösen und bestimmte Teile der industriellen Produktion anziehen - auch Pull-Effekt genannt.

Cross-country evidence on the adoption of energy-efficient retrofit measures (EERMs) in residential buildings is critical to supporting the development of national and pan-European policies aimed at fostering the energy performance upgrade of the building stock. In this light, the aim of this paper is to advance in the understanding of the probability of certain EERMs taking place in eight EU countries, according to a set of parameters, such as building typology, project types, and motivation behind the project. Using these parameters collected via a multi-country online survey, a set of discrete-choice (conditional logit) models are estimated on the probability of selecting a choice of any combination of 33 EERMs across the sampled countries. Results show that actions related to the building envelope are the most often-addressed across countries and single building elements or technology measures have a higher probability of being implemented. The modelling framework developed in this study contributes to the scientific community in three ways: (1) establishing an empirical relationship among EERMs and project (i.e., retrofit and deep retrofit), (2) identifying commonalities and differences across the selected countries, and (3) quantifying the probabilities and market shares of various EERMs.

Citizen science is a transdisciplinary approach that responds to the current science policy agenda: in terms of supporting open science, and by using a range of science communication instruments. In particular, it opens up scientific research processes by involving citizens at different phases; this also creates a range of opportunities for science communication to happen This article explores methodological and practical characteristics of citizen science as a form of science communication by examining three case studies that took different approaches to citizens' participation in science. Through these, it becomes clear that communication in citizen science is "always" science communication and an essential part of "doing science".

Staying within the 2 °C (preferably 1.5 °C) limit requires fast and fundamental system changes, also in urban passenger transport. Shifting car traffic to environmentally friendly transport modes is one central strategy to make urban transport more sustainable and climate friendly. However, in most cities car use remains high. Therefore, this paper analyzes what course change is needed regarding direction, scale and speed of change for urban sustainability and climate protection reasons. The paper analyzes the role of modal shift as a strategy in itself and in relation to land-use (avoid) and efficiency (improve) measures. The paper draws on insights from European frontrunning cities and explorative forecasting scenarios calculated with the sophisticated integrated land-use transport model "Ruhr Region 2050". The paper suggests that a significant reduction of urban car use is needed (direction) that roughly equals a fast halving of car use (scale), which has proven feasible under the current socio-political conditions by annual reduction rates of 0.5 to 1.5 percentage points of the trip-based modal share of car use (speed). Significantly reducing car use requires comprehensive and high-intensive measures that go far beyond usual practices. Modal shift measures need to play a crucial role in integrated approaches with land-use (avoid) and efficiency (improve) measures because they have the potential to significantly reduce car use and CO2 emissions and because they can produce comparatively fast effects - which makes modal shift measures first aid approaches to achieve a fast "bending of the curve" of excessive car use and growing CO2 emissions.

Reuse is still seen as a "niche phenomenon" and consumers seem to waste economic opportunities linked to buying and selling second-hand products. For this reason, this paper focuses on incentives and barriers to sell and buy second-hand products, as indicated in the literature, and applies a theoretical framework of transaction costs to explain the existing consumption patterns. For this paper, a representative online survey was conducted in which 1023 consumers in Germany participated, age 16 and older. The data were analyzed for statistically significant deviations between different groups of economic actors selling or buying second-hand products. Results show that valuable unused products exist in households, but barriers such as uncertainties about the reliability of the buyer or the quality of the product hinder the transition into sustainable consumption. Different forms of transaction costs are important explanatory variables to explain why consumers nevertheless predominantly buy new products, although they are aware that second-hand would save money and make an individual contribution to climate protection.

This article develops a sectoral approach to the analysis of global climate governance. This approach advances the assessment of global climate governance by focusing on complexes of intergovernmental and transnational institutions co-governing key socio-technical sectoral systems. The actual and potential contribution of these sectoral institutional complexes to advancing decarbonization can be assessed according to five key governance functions: (1) providing guidance and signal to actors, (2) setting rules to facilitate collective action, (3) enhancing transparency and accountability, (4) offering support (finance, technology, capacity-building), and (5) promoting knowledge and learning. On this basis, we can assess the potential of international cooperation to address the challenges specific sectoral systems face in the climate transition as well as the extent to which existing sectoral institutional complexes deliver on this potential. This provides a solid starting point for developing options for filling identified gaps and enhancing the effectiveness of global climate governance.

The Digital Product Passport (DPP) is a concept of a policy instrument particularly pushed by policy circles to contribute to a circular economy. The preliminary design of the DPP is supposed to have product-related information compiled mainly by manufactures and, thus, to provide the basis for more circular products. Given the lack of scientific debate on the DPP, this study seeks to work out design options of the DPP and how these options might benefit stakeholders in a product's value chain. In so doing, we introduce the concept of the DPP and, then, describe the existing regime of regulated and voluntary product information tools focusing on the role of stakeholders. These initial results are reflected in an actor-centered analysis on potential advantages gained through the DPP. Data is generated through desk research and a stakeholder workshop. In particular, by having explored the role the DPP for different actors, we find substantial demand for further research on a variety of issues, for instance, on how to reduce red tape and increase incentives for manufacturers to deliver certain information and on how or through what data collection tool (e.g., database) relevant data can be compiled and how such data is provided to which stakeholder group. We call upon other researchers to close the research gaps explored in this paper also to provide better policy direction on the DPP.

This concluding article derives six major findings from the contributions to this special issue. First, the barriers and challenges to decarbonisation vary significantly across sectoral systems. Second, and similarly, the need and potential for the five functions of international governance institutions to contribute to effective climate protection also vary widely. Third, while the pattern is uneven, there is a general undersupply of international climate governance. Fourth, the sectoral analyses confirm that the UNFCCC and Paris Agreement play an important overarching role but remain limited in advancing effective sectoral governance. Fifth, while non-environmental institutions may present important barriers to decarbonisation, more synergistic effects are possible. Sixth, our sectoral approach provides a sound basis on which to identify sector-specific policy options. The paper then offers reflections on the merits and limitations of the sectoral approach, before identifying avenues for future research to further advance the agenda.

This paper develops policy measures for a "just transition" based on a case study conducted in Germany's Rhineland lignite mining district. Semi-structured guided interviews served as the methodological approach. Expert interviews were conducted with representatives of citizen initiatives, trade unions and the Federal State of North Rhine-Westphalia. The results reveal the need for policy measures in different areas: First, employees working for subcontractors of the lignite industry have a high risk of losing their jobs because there are virtually no support policies for them. Second, there needs to be more input by civic initiatives regarding the process of structural change. And last, land needs to be prevented from becoming a scarce resource in the Rhineland area due to current mining legislation. We use an actor-centred institutionalist framework to derive governance approaches in line with the needs of various stakeholders.

This paper examines the Global Climate Action Agenda (GCAA) and discusses options to improve sub- and non-state involvement in post-2020 climate governance. A framework that stimulates sub- and non-state action is a necessary complement to national governmental action, as the latter falls short of achieving low-carbon and climate-resilient development as envisaged in the Paris Agreement. Applying design principles for an ideal-type orchestration framework, we review literature and gather expert judgements to assess whether the GCAA has been collaborative, comprehensive, evaluative and catalytic. Results show that there has been greater coordination among orchestrators, for instance in the organization of events. However, mobilization efforts remain event-driven and too little effort is invested in understanding the progress of sub- and non-state action. Data collection has improved, although more sophisticated indicators are needed to evaluate climate and sustainable development impacts. Finally, the GCAA has recorded more action, but relatively little by actors in developing countries. As the world seeks to recover from the COVID-19 crisis and enters a new decade of climate action, the GCAA could make a vital contribution in challenging times by helping governments keep and enhance climate commitments; strengthening capacity for sub- and non-state action; enabling accountability; and realizing sustainable development.

Unser Papier entwickelt Maßnahmen für eine "Just transition"-Governance als Grundlage einer Politischen Ökonomie im Strukturwandel. Für eine Fallstudie im Rheinischen Braunkohlerevier wurden sechs Experteninterviews mit Bürgerinitiativen, Gewerkschaften und Vertretern des Landes Nordrhein-Westfalen durchgeführt. Die Ergebnisse zeigen den Bedarf an politischen Maßnahmen in verschiedenen Bereichen auf: Während für die Traditionsfirmen der Braunkohleindustrie und deren Beschäftigten eine Vielzahl von Förderpolitiken entwickelt wurde und wird, erhalten Beschäftigte von Subunternehmen kaum Unterstützung im Strukturwandel. Letztere sind daher einem hohen Risiko ausgesetzt, durch den Ausstieg aus der Kohleförderung ihren Arbeitsplatz zu verlieren. Die Interviews zeigten auch, dass im Rheinischen Braunkohlerevier aufgrund des geltenden Bergbaugesetzes Flächen zu einer knappen Ressource werden könnten. Der Akteurszentrierte Institutionalismus wird genutzt, um Maßnahmen abzuleiten, die den Bedürfnissen der verschiedenen Interessengruppen entsprechen. Abschließend werden Bezüge sowohl zum Transition Management als auch zur Politischen Ökonomie hergestellt.

Agriculture is an economic sector with massive impact on biodiversity and agrobiodiversity. Sustainable diets represent a critical policy leverage and a realistic opportunity to reduce the environmental impact of the agro-food sector while improving human health at the same time. Eating out is an increasingly common habit for many consumers and, by offering sustainable dishes, catering companies can play a central role. To do this, they need to understand and correctly assess the sustainability of their food portfolio, but assessment tools are not well established yet. The NAHGAST project, of which this study was part, developed and tested a sustainability assessment tool for catering companies based on concrete targets defined per meal. This study addresses the lack of methods to evaluate the impact of food on biodiversity, with a particular focus on agrobiodiversity. The work illustrates a context-specific application of an enhanced DPSIR model to structure information and select indicators, and proposes a transdisciplinary use of existing metrics. Further research is needed in order to define scientifically sound target values or sustainability ranges for each indicator per meal, in order to calculate them. Strengths and limits of the study are discussed.

Practices of urban experimentation are currently seen as a promising approach to making planning processes more collaborative and adaptive. The practices develop not only in the context of ideal-type concepts of urban experiments and urban labs but also organically in specific governance contexts. We present such an organic case in the city of Wuppertal, Germany, centred around a so-called change-maker initiative, "Utopiastadt." This initiative joined forces with the city administration and collaborated with a private property owner and the local economic development agency in an unusual planning process for the development of a central brownfield site. Ultimately, the consortium jointly published a framework concept that picked up the vision of the "Utopiastadt Campus" as an open-ended catalyst area for pilot projects and experiments on sustainability and city development. The concept was adopted by the city council and Utopiastadt purchased more than 50% of the land. In order to analyse the wider governance context and power struggles, we apply the social-constructivist theory of Strategic Action Fields (SAFs). We focused on the phases of contention and settlement, the shift in interaction forms, the role of an area development board as an internal governance unit and the influences of proximate fields, strategic action, and state facilitation on the development. We aim to demonstrate the potential of the theory of SAFs to understand a long-term urban development process and how an episode of experimentation evolved within this process. We discuss the theory's shortcomings and reflect critically on whether the process contributed to strengthening collaborative and experimental approaches in the governance of city development.

We conduct a systematic, interdisciplinary review of empirical literature assessing evidence on induced innovation in energy and related technologies. We explore links between demand-drivers (both market-wide and targeted); indicators of innovation (principally, patents); and outcomes (cost reduction, efficiency, and multi-sector/macro consequences). We build on existing reviews in different fields and assess over 200 papers containing original data analysis. Papers linking drivers to patents, and indicators of cumulative capacity to cost reductions (experience curves), dominate the literature. The former does not directly link patents to outcomes; the latter does not directly test for the causal impact of on cost reductions). Diverse other literatures provide additional evidence concerning the links between deployment, innovation activities, and outcomes. We derive three main conclusions. (1) Demand-pull forces enhance patenting; econometric studies find positive impacts in industry, electricity and transport sectors in all but a few specific cases. This applies to all drivers - general energy prices, carbon prices, and targeted interventions that build markets. (2) Technology costs decline with cumulative investment for almost every technology studied across all time periods, when controlled for other factors. Numerous lines of evidence point to dominant causality from at-scale deployment (prior to self-sustaining diffusion) to cost reduction in this relationship. (3) Overall Innovation is cumulative, multi-faceted, and self-reinforcing in its direction (path-dependent). We conclude with brief observations on implications for modeling and policy. In interpreting these results, we suggest distinguishing the economics of active deployment, from more passive diffusion processes, and draw the following implications. There is a role for policy diversity and experimentation, with evaluation of potential gains from innovation in the broadest sense. Consequently, endogenising innovation in large-scale models is important for deriving policy-relevant conclusions. Finally, seeking to relate quantitative economic evaluation to the qualitative socio-technical transitions literatures could be a fruitful area for future research.

Electric mobility is beginning to enter East African cities. This paper aims to investigate what policy-level solutions and stakeholder constellations are established in the context of electric mobility (e-mobility) in Dar es Salaam, Kigali, Kisumu and Nairobi and in which ways they attempt to tackle the implementation of electric mobility solutions. The study employs two key methods including content analysis of policy and programmatic documents and interviews based on a purposive sampling approach with stakeholders involved in mobility transitions. The study findings point out that in spite of the growing number of policies (specifically in Rwanda and Kenya) and on-the-ground developments, a set of financial and technical barriers persists. These include high upfront investment costs in vehicles and infrastructure, as well as perceived lack of competitiveness with fossil fuel vehicles that constrain the uptake of e-mobility initiatives. The study further indicates that transport operators and their representative associations are less recognized as major players in the transition, far behind new e-mobility players (start-ups) and public authorities. This study concludes by identifying current gaps that need to be tackled by policymakers and stakeholders in order to implement inclusive electric mobility in East African cities, considering modalities that include transport providers and address their financial constraints.

Electronics containing growing quantities of high value and critical metals are increasingly used in automobiles. The conventional treatment practice for end-of-life vehicles (ELV) is shredding after de-pollution and partial separation of spare parts. Despite opportunities for resource recovery, the selective separation of components containing relevant amounts of critical metals for the purpose of material recycling is not commonly implemented. This article is aimed to contribute to recycling strategies for future critical metal quantities and the role of extended material recovery from ELVs. The study examines the economic feasibility of dismantling electronic components from ELVs for high value metal recycling. The results illustrate the effects of factors as dismantling time, labour costs and logistics on the economic potential of resource recovery from ELVs. Manual dismantling is profitable for only a few components at the higher labour costs in western/northern parts of Europe and applicable material prices, including the inverter for hybrid vehicles, oxygen sensor, side assistant sensor, distance and near distance sensors. Depending on the vehicle model, labour costs and current material prices, manual dismantling can also be cost-efficient for also some other such as the heating blower, generator, starter, engine and transmission control, start/stop motor, drive control, infotainment and chassis control.

The ongoing warming of the Earth's atmosphere is projected to cause a northward shift of species' distributions, as they track their climatic optimum. In the rapidly warming Arctic, this has already led to an increase of shrubs in tundra ecosystems. While this northern expansion of woody biomass has been studied relatively extensively over the last decade, little research has been devoted to shrub growth responses at the southern margins of Northern Hemisphere shrubs. Here, we studied shoot length growth, its responses to climate over the period 2010-2017, and differences in leaf C and N content of the evergreen dwarf shrub Empetrum nigrum, as well as the vegetation composition and soil parameters at four sites located along a gradient of increasing dune age on the island Spiekeroog, northern Germany. The sites are located in the tri-national UNESCO world heritage site, the Wadden Sea. E. nigrum has a predominantly circum-arctic-boreal distribution and its southern distribution margin in European lowlands runs through northern Germany, where it is retreating northwards. We found a negative response to autumn (surface) temperatures and previous summer surface temperatures and/or a positive response to summer precipitation of E. nigrum growth, except at the oldest dune with the strongest E. nigrum dominance. Growth rates and plant species diversity declined with dune age. Our results suggest that E. nigrum growth is drought sensitive at its European southern range margin. We hypothesize that this sensitivity may form the basis for its northward retreat, which is supported by recent observations of E. nigrum dieback in Germany after the extreme drought in 2018 and model projections.

The number of input-output assessments focused on energy has grown considerably in the last years. Many of these assessments combine data from multi-regional input-output (MRIO) databases with energy extensions that completely or partially depict the different stages through which energy products are supplied or used in the economy. The improper use of some energy extensions can lead to double accounting of some energy flows, but the frequency with which this happens and the potential impact on the results are unknown. Based on a literature review, we estimate that around a quarter of the MRIO-based energy assessments reviewed incurred into double accounting. Using the EXIOBASE MRIO database, we also analyse the effects of double accounting in the absolute values and rankings of different countries' and products' energy footprints. Building on the insights provided by our analysis, we offer a set of key recommendations to MRIO users to avoid the double accounting problem in the future. Likewise, we conclude that the harmonisation of the energy data across MRIO databases led by experts could simplify the choices of the data users until the provision of official energy extensions by statistical offices becomes a widespread practice.

Die nationale Wasserstoffstrategie der Bundesregierung beinhaltet zentrale Zielkonflikte: Stärkung der deutschen Wirtschaft versus hohe Importquote, günstigere Produktionskosten im Ausland versus höhere Wertschöpfung durch Produktion im Inland. Vor diesem Hintergrund wird in diesem Beitrag diskutiert, wie groß die Kostenunterschiede ausfallen, welche Bedeutung die Transportkosten haben und welche Reboundeffekte bei Importen aus Nordafrika zu beachten sind.

Cities are becoming digital and are aiming to be sustainable. How they are combining the two is not always apparent from the outside. What we need is a look from inside. In recent years, cities have increasingly called themselves Smart City. This can mean different things, but generally includes a look towards new digital technologies and claim that a Smart City has various advantages for its citizens, roughly in line with the demands of sustainable development. A city can be seen as smart in a narrow sense, technology wise, sustainable or smart and sustainable. Current city rankings, which often evaluate and classify cities in terms of the target dimensions 2smart" and "sustainable", certify that some cities are both. In its most established academic definitions, the Smart City also serves both to improve the quality of life of its citizens and to promote sustainable development. Some cities have obviously managed to combine the two. The question that arises is as follows: What are the underlying processes towards a sustainable Smart City and are cities really using smart tools to make themselves sustainable in the sense of the 2015 United Nations Sustainability Goal 11? This question is to be answered by a method that has not yet been applied in research on cities and smart cities: the innovation biography. Based on evolutionary economics, the innovation biography approaches the process towards a Smart City as an innovation process. It will highlight which actors are involved, how knowledge is shared among them, what form citizen participation processes take and whether the use of digital and smart services within a Smart City leads to a more sustainable city. Such a process-oriented method should show, among other things, to what extent and when sustainability-relevant motives play a role and which actors and citizens are involved in the process at all.

Flexible, system-oriented operating strategies are becoming increasingly important in terms of achieving a climate-neutral energy system transformation. Solid-oxide electrolysis (SOEC) can play an important role in the production of green synthesis gas from renewable energy in the future. Therefore, it is important to investigate the extent to which SOEC can be used flexibly and which feedback effects and constraints must be taken into account. In this study, we derived a specific load profile from an energy turnaround scenario that supports the energy system. SOEC short-stacks were operated and we investigated the impact that the load profile has on electrical stack performance and stack degradation as well as the product gas composition by means of Fourier-transform infrared spectroscopy. The stacks could follow the grid-related requirement profiles of secondary control power and minute reserves very well with transition times of less than two minutes per 25% of relative power. Only short-term disturbances of the H2/CO ratio were observed during transitions due to the adjustment of feed gases. No elevated degradation effects resulting from flexible operation were apparent over 1300 h, although other causes of degradation were present.

Water availability plays an important role in the expansion planning of utility-scale solar power plants, especially in the arid regions of the Middle East and North Africa. Although these power plants usually account for only a small fraction of local water demand, competition for water resources between communities, farmers, companies, and power suppliers is already emerging and is likely to intensify in future. Despite this, to date there has been a lack of comprehensive studies analyzing interdependencies and potential conflicts between energy and water at local level. This study addresses this research gap and examines the linkages between water resources and energy technologies at local level based on a case study conducted in Ouarzazate, Morocco, where one of the largest solar power complexes in the world was recently completed. To better understand the challenges faced by the region in light of increased water demand and diminishing water supply, a mixed-method research design was applied to integrate the knowledge of local stakeholders through a series of workshops. In a first step, regional socio-economic water demand scenarios were developed and, in a second step, water saving measures to avoid critical development pathways were systematically evaluated using a participatory multi-criteria evaluation approach. The results are a set of water demand scenarios for the region and a preferential ranking of water saving measures that could be drawn upon to support decision-making relating to energy and water development in the region.

The transdisciplinary research mode has gained prominence in the research on and for sustainability transformations. Yet, solution-oriented research addressing complex sustainability problems has become complex itself, with new transdisciplinary research formats being developed and tested for this purpose. Application of new formats offers learning potentials from experience. To this end, we accompanied fourteen research projects conceptualized as real-world labs (RwLs) from 2015 to 2018. RwLs were part of a funding program on "Science for Sustainability" in the German federal state of Baden-Württemberg. Here, we combine conceptual and empirical work to a structured collection of experiences and provide a comprehensive account of RwLs. First, we outline characteristics of RwLs as transformation oriented, transdisciplinary research approach, using experiments, enabling learning and having a long-term orientation. Second, we outline eleven success factors and concrete design notes we gained through a survey of the 14 RwLs: (1) find the right balance between scientific and societal aims, (2) address the practitioners needs and restrictions, (3) make use of the experimentation concept, (4) actively communicate, (5) develop a "collaboration culture", (6) be attached to concrete sites, (7) create lasting impact and transferability, (8) plan for sufficient time and financial means, (9) adaptability, (10) research-based learning, and (11) recognize dependency on external actors. Characteristics and success factors are combined to illustrate practical challenges in RwLs. Third, we show which methods could be used to cope with challenges in RwLs. We conclude discussing the state of debate on RwLs and outline future avenues of research.

Quantitative environmental assessments are crucial in working effectively towards sustainable production and consumption patterns. Over the last decades, life cycle assessments (LCA) have been established as a viable means of measuring the environmental impacts of products along the supply chain. In regard to user and consumption patterns, however, methodological weaknesses have been reported and, several attempts have been made to improve LCA accordingly, for example, by including higher order effects and behavioural science support. In a discussion of such approaches, we show that there has been no explicit attention to the concepts of consumption, often leading to product-centred assessments. We introduce social practice theories in order to make consumption patterns accessible to LCA. Social practices are routinised actions comprising interconnected elements (materials, competences, and meanings), which make them conceivable as one entity (e.g. cooking). Because most social practices include some sort of consumption (materials, energy, air), we were able to develop a framework which links social practices to the life cycle inventory of LCA. The proposed framework provides a new perspective of quantitative environmental assessments by switching the focus from products or users to social practices. Accordingly, we see the opportunity in overcoming the reductionist view that people are just users of products, and instead we see them as practitioners in social practises. This change could enable new methods of interdisciplinary research on consumption, integrating intend-oriented social sciences and impact-oriented assessments. However, the framework requires further revision and, especially, empirical validation.

Water and energy are two pivotal areas for future sustainable development, with complex linkages existing between the two sectors. These linkages require special attention in the context of the energy transition. Against this background, this paper analyses the role of water availability in the development of solar thermal and photovoltaic power plants for the case of the Draa Valley in southern Morocco. Located in a semi-arid to arid mountainous area, the Drâa Valley faces high water stress - a situation expected to worsen due to climate change. At the same time, the region has one of the greatest potentials for solar energy in the world. To examine whether limited water availability could accelerate or delay the implementation of solar thermal and photovoltaic power plants, this paper compares regional water availability and demand in the Draa Valley for different scenarios, paying particular attention to potential socio-economic development pathways. The Water Evaluation and Planning System software is applied to allocate the water resources in the study region. The water supply is modelled under the Representative Concentration Pathway 8.5 climate scenario, while the water demand for the Drâa Valley is modelled for a combination of three socio-economic and two energy scenarios. The climate scenario describes a significant decrease in water availability by 2050, while the socio-economic and energy scenarios show an increase in water demand. The results demonstrate that during a sequence of dry years the reservoirs water availability is reduced and shortages in water supply can result in high levels of unmet demand. If this situation occurs, oasis farming, water for drinking and energy production could compete directly with each other for water resources. The energy scenarios indicate that the use of dry cooling technologies in concentrated solar power and photovoltaic hybrid systems could be one option for reducing competition for the scarce water resources in the region. However, given that energy generation accounts for only a small share of the regional water demand, the results also suggest that socio-economic demand reduction, especially in the agricultural sector, for example by reducing the cultivated area, will most likely become necessary.

This paper explores how the European Commission promotes the concept of Sustainable Urban Mobility Planning (SUMP) among European cities. Despite the strong uptake of the SUMP concept, mobility-related problems persist in European municipalities. Linking theoretical approaches to understand the diffusion of policies with empirical findings from working with cities in the SUMP context, this article explores channels of policy diffusion and investigates shortcomings related to the respective approaches. Studies on the diffusion, the transfer and the convergence of policies identify formal hierarchy, coercion, competition, learning and networking, and the diffusion of international norms as channels for policy transfer. The findings which are presented in this paper are twofold: First, the paper finds evidence that the Commission takes different roles and uses all mechanisms in parallel, albeit with different intensity. It concludes that the approaches to explain policy diffusion are not competing or mutually exclusive but are applied by the same actor to address different aspects of a policy field, or to reach out to different actors. Second, the article provides first evidence of factors that limit the mechanisms' abilities to directly influence urban mobility systems and mobility behaviour.

Prepaid-Stromzähler sind in Deutschland noch selten, bieten jedoch zukünftig einen interessanten Markt. Vor allem kleinere Anbieter, aber auch erste Regionalversorger kombinieren die Megatrends Digitalisierung und Energiewende und kreieren daraus neue Dienstleistungen. Zusammen mit IT-Firmen entwickeln sie daraus neue Geschäftsideen, die auch hinsichtlich sozialer Aspekte hohen Anforderungen genügen. Der Rollout von Smart Metering-Lösungen eröffnet zukünftig noch größere Chancen, durch Echtzeit-Datenerfassung den Energieverbrauch und damit auch Einsparpotenziale transparent zu machen. Hochaufgelöste Daten ermöglichen innovative Dienstleistungen und bringen die Kundenbeziehung auf eine neue Ebene.

At the heart of transition research lies the question of how to "scale up" sustainable alternatives from a protected niche to the creation of mainstream practices. While upscaling processes are often seen as an essential element that contributes to societal transformation, upscaling itself remains a fuzzy concept. We argue that some fundamental dilemmas of upscaling can be identified, for example, the different understanding of the concept by researchers and practitioners. The dilemmas should be addressed in a more reflexive way by those from the worlds of science and practice who are involved in collaborative research settings.

The paper provides an integrated assessment of environmental and socio-economic effects arising from final consumption of food products by European households. Direct and indirect effects accumulated along the global supply chain are assessed by applying environmentally extended input-output analysis (EE-IOA). EXIOBASE 3.4 database is used as a source of detailed information on environmental pressures and world input-output transactions of intermediate and final goods and services. An original methodology to produce detailed allocation matrices to link IO data with household expenditure data is presented and applied. The results show a relative decoupling between environmental pressures and consumption over time and shows that European food consumption generates relatively less environmental pressures outside Europe (due to imports) than average European consumption. A methodological framework is defined to analyze the main driving forces by means of a structural decomposition analysis (SDA). The results of the SDA highlight that while technological developments and changes in the mix of consumed food products result in reductions in environmental pressures, this is offset by growth in consumption. The results highlight the importance of directing specific research and policy efforts towards food consumption to support the transition to a more sustainable food system in line with the objectives of the EU Farm to Fork Strategy.

Decarbonizing transportation in emerging economies will be one of the key challenges in global climate change mitigation efforts. In this paper, pathways are developed towards achieving a 1.5° degree scenario for land-transport for four emerging economies (Brazil, India, Kenya and Vietnam). The aim is to highlight the key opportunities and challenges for low-carbon transport in countries with rapidly growing mobility demand. The main focus of this paper is to reconcile actual and required emission reduction targets and develop plausible pathways to achieve these targets. The paper also identifies potential strategies and measures for these countries to follow these pathways. The analysis considers the contributions of "avoid" (cutting travel growth), "shift" (to lower CO2 modes) and "improve" (vehicle and fuel CO2 characteristics) interventions to decarbonisation scenarios. These scenarios aim to inform renewed Nationally Determined Contributions and shed light on the feasibility of deep decarbonisation pathways that would be in line with the Paris Agreement. Results from this study show that achieving 1.5DS would require dramatic changes in travel patterns, technology and fuels, and major intensification of current policy approaches. Decarbonization solutions will need to include greater use and investment of efficient modes, major shifts toward near-zero carbon fuels such as clean electricity, systems integration, modal shift and urban planning solutions. Although the socio-economic situations and national transport systems differ between the selected countries, some fairly similar strategies appear likely to be core to the mitigation effort, such as rapid growth in light- and heavy-duty vehicle electrification and investments in public transit systems.

The mass roll out of solar PV across the Global South has enabled electricity access for millions of people. In the right context, Small Wind Turbines (SWTs) can be complementary, offering the potential to generate at times of low solar resource (night, monsoon season, winter, etc.) and increasing the proportion of the total energy system that can be manufactured locally. However, many contextual factors critically affect the viability of the technology, such as the extreme variability in the wind resource itself and the local availability of technical support. Therefore, performing a detailed market analysis in each new context is much more important. The Wind Empowerment Market Assessment Methodology (WEMAM) is a multi-scalar, transdisciplinary methodology for identifying the niche contexts where small wind can make a valuable contribution to rural electrification. This paper aims to inform the development of WEMAM with a critical review of existing market assessment methodologies. By breaking down WEMAM into its component parts, reflecting upon its practical applications to date and drawing upon insights from the literature, opportunities where it could continue to evolve are highlighted. Key opportunities include shifting the focus towards development outcomes; creating community archetypes; localised studies in high potential regions; scenario modelling and MCDA ranking of proposed interventions; participatory market mapping; and applying socio-technical transitions theory to understand how the small wind niche can break through into the mainstream.

Die explosive Verbreitung des Corona-Virus über die Welt brachte ein Realexperiment globaler Dimension mit offenem Ausgang hervor. Gesellschaften formieren sich, kosmopolitisch verschränkt, als Hygienegesellschaften. Zwischen striktem Lockdown und minimaler Begrenzung gehen sie je eigene experimentelle Wege. Dabei wird der Raum des Experimentellen bisher eher defensiv gestaltet, was in der Konsequenz zur Begrenzung experimenteller Räume sowie zur schleichenden Delegitimierung von Kontrollpolitiken der Pandemie führt. Die These dieses Beitrags lautet, dass solche Legitimationsprobleme umso eher gelöst werden können, je eher Strukturen resilienten Experimentierens entworfen und institutionalisiert werden. Ein wichtiges Ergebnis der Überlegungen ist, dass die resiliente Gestaltung experimenteller Räume zur Bewältigung solchen Krisengeschehens nur gelingen kann, wenn neben top-down verordneten Kontrollen sich eine bottom-up-Kultur sozialen Experimentierens entfalten kann. Dies setzt auf Seiten der Zivilgesellschaft ebenso wie von staatlicher Seite die Fähigkeit und den Willen zu Partizipation und Kooperation voraus. Entsprechende Ansatzpunkte werden dafür identifiziert.

Many technical solutions have been developed to enhance the energy efficiency in buildings. However, the actual effectiveness and sustainability of these solutions often do not correspond to expectations because of the missing perspective of design, user's real needs, and unconsidered negative side effects of their use (rebounds). With the aim to help address these challenges, this paper presents results of a longitudinal living lab study and proposes a user-centered building management system (UC-BMS) as a prototype for office buildings. Based on mixed methods, UC-BMS was co-developed, tested, and evaluated in Germany in up to six office buildings, 85 offices, and within two heating periods. The results demonstrate that such user-oriented approach can save up to 20% of energy while maintaining or even improving comfort and work productivity. The findings show three main areas of intervention and elements of UC-BMS: (1) How interactive design and feedback systems (e.g., air quality) can stimulate ventilation practices and energy efficiency in offices and (2) supporting heating system optimization e.g., by better understanding office behavior. (3) Finally, an office comfort survey was conducted to enable communication between facility management and office users and thus limiting complaints and adapting the heating system towards actual office user needs.

In this paper, we aim to present a comprehensive analysis on the emerging phenomenon of distributed innovation in commons-based peer production (CBPP) platforms. Starting with the exploration of the widely held belief on value-creation confined to industrial settings, we raise several questions regarding the feasibility of, and a need for, an inclusive innovation process that can tap grassroots capacity into both traditional (industrial research and development) and emerging (peer-to-peer) innovation models to yield sustainable solutions. In particular, we explore the emergence and structuration of digital innovations in the maker movement, as it presents an alternative construct of innovation wherein access to and sharing of knowledge is predominantly distributed. With innovation outcomes often freely revealed, its very structuration could pose a principal challenge to our conceptualizations of value creation and competitive advantage in the current economic model. Drawing from responses received from 200 collaborative innovation platforms, six semi‐structured interviews focusing on socio-technical innovation cases, as well as four in-depth narrative interviews with maker turned entrepreneurs, we present a detailed analysis on the topology of network, typology of actors, as well as the underlying innovation ecosystem in CBPP networks in Germany. In doing so, we contribute to the conceptualization of peer-to-peer distributed innovations in collaborative platforms.

Integrated assessment models (IAMs) are commonly used by decision makers in order to derive climate policies. IAMs are currently based on climate-economics interactions, whereas the role of social system has been highlighted to be of prime importance on the implementation of climate policies. Beyond existing IAMs, we argue that it is therefore urgent to increase efforts in the integration of social processes within IAMs. For achieving such a challenge, we present some promising avenues of research based on the social branches of economics. We finally present the potential implications yielded by such social IAMs.

Given large potentials of the MENA region for renewable energy production, transitions towards renewables-based energy systems seem a promising way for meeting growing energy demand while contributing to greenhouse gas emissions reductions according to the Paris Agreement at the same time. Supporting and steering transitions to a low-carbon energy system require a clear understanding of socio-technical interdependencies in the energy system as well as of the principle dynamics of system innovations. For facilitating such understanding, a phase model for renewables-based energy transitions in MENA countries, which structures the transition process over time through the differentiation of a set of sub-sequent distinct phases, is developed in this article. The phase model builds on a phase model depicting the German energy transition, which was complemented by insights about transition governance and adapted to reflect characteristics of the MENA region. The resulting model includes four phases ("Take-off renewables", "System integration", "Power to fuel/gases”, "Towards 100% renewables”), each of which is characterized by a different cluster of innovations. These innovations enter the system via three stages of development which describe different levels of maturity and market penetration, and which require appropriate governance. The phase model has the potential to support strategy development and governance of energy transitions in MENA countries in two complementary ways: it provides an overview of techno-economic developments as orienting guidelines for decision-makers, and it adds some guidance as to which governance approaches are suitable for supporting those developments.

Kommunen und kommunale Unternehmen können ihre Vorbildfunktion in einer integrierten Stadt- und Verkehrsplanung nutzen, indem sie die Elektrifizierung ihrer Flotte an leichten Nutzfahrzeugen voranbringen. Das kann die Treibhausgasemissionen und Stickstoffdioxidemissionen mindern und einer nachhaltigen Verkehrsentwicklung dienen. Klimaschutz durch Minderung der Kohlendioxidemissionen und Gesundheitsschutz durch Minderung der Stickstoffdioxidemissionen sind zwei zentrale Gründe für eine Flottenwende - auch bei den leichten Nutzfahrzeugen.

Biomass-fueled combined heat and power systems (CHPs) can potentially offer environmental benefits compared to conventional separate production technologies. This study presents the first environmental life cycle assessment (LCA) of a novel high-efficiency bio-based power (HBP) technology, which combines biomass gasification with a 199 kW solid oxide fuel cell (SOFC) to produce heat and electricity. The aim is to identify the main sources of environmental impacts and to assess the potential environmental performance compared to benchmark technologies. The use of various biomass fuels and alternative allocation methods were scrutinized. The LCA results reveal that most of the environmental impacts of the energy supplied with the HBP technology are caused by the production of the biomass fuel. This contribution is higher for pelletized than for chipped biomass. Overall, HBP technology shows better environmental performance than heat from natural gas and electricity from the German/European grid. When comparing the HBP technology with the biomass-fueled ORC technology, the former offers significant benefits in terms of particulate matter (about 22 times lower), photochemical ozone formation (11 times lower), acidification (8 times lower) and terrestrial eutrophication (about 26 times lower). The environmental performance was not affected by the allocation parameter (exergy or economic) used. However, the tested substitution approaches showed to be inadequate to model multiple environmental impacts of CHP plants under the investigated context and goal.

China's regular energy statistics does not include the building sector, and data on building energy demand is included in other types of energy consumption in the Energy Balance Sheet (EBS). Therefore data on building energy demand is not collected based on statistics, but rather calculated or estimated by various approaches in China. This study aims at developing and testing China's building energy statistics by applying an adapted EBS. The advantage of the adapted EBS is that statistical data is from the regular statistical system and no additional statistical efforts are needed. The research result shows that the adapted EBS can be included in China regular energy statistical system and can be standardized in a transparent way. Testing of the adapted EBS shows that China's building energy demand has shown an annual increase of 7.6% since 2001, and a lower contribution to the total energy demand as compared to the developed world. There is also a close link to lifestyle and living standard while industrial energy demand is mainly driven by economy and decoupling of building energy demand with increasing of building floor area, this is due to a considerable improvement of building energy efficiency. The adapted EBS creates a method for China conducting statistics of building energy consumption at the sector level in a uniform way and serves as the basis for any sound building energy efficiency policy decisions.

On September 17, 2019, EU Competition Commissioner Margrethe Vestager allowed the electricity company Eon to take over and break up RWE subsidiary Innogy under lenientconditions. But there are numerous experts who have a different opinion and argue that the EU Commission approval is a "decision of enormous importance" that will "fundamentally change the entire sector". The result of this decision is that this mega-deal creates two monolithic giants in the German energy sector with unprecedented market power. If one compares the situation with the purchase of the electricity supplier Nuon by Vattenfall in 2009, questions arise. Back then, the competition authorities forced Vattenfall to divest parts of Nuon's business in individual cities, which resulted in the supplier "lekker energie". Following this example, the competition authorities should have consistently forced Eon to sell parts of the business, such as larger distribution companies. A transaction of this magnitude should always be viewed critically in competition law. The legitimate question therefore arises as to why the German and European competition authorities (the Federal Cartel Office, the Federal Network Agency, the Monopolies Commission and the European Competition Commission) faced this deal with barely audible criticism and why they did not react with far-reaching prohibition requirements. "Competition doubts are certainly justified". Because if the two largest German energy groups completely eliminate each other's competition and completely divide up their business areas among themselves, this will have far-reaching consequences for the energy sector. Especially against the background that the energy transition in Germany has so far been characterised by decentralised structures and civic participation (especially in the case of electricity generation from renewable energies). In this paper, the authors will demonstrate what this Eon/RWE deal means for competition and the energy transition.

The annual Climate Change Conference took place on 2-15 December in Katowice, Poland. It included the twenty-fourth Conference of the Parties (COP-24) to the UN Framework Convention on Climate Change (UNFCCC), the fourteenth Meeting of the Parties to the Kyoto Protocol (MOP-14), the resumed first Meeting of the Parties to the Paris Agreement (MOP-1), and their subsidiary bodies. The conference had two main objectives: operationalizing the Paris Agreement by adopting detailed rules for its implementation and starting the process of strengthening the parties' climate protection contributions.

It has been widely recognized that there is an urgent need for more sustainable urban transport policy and planning. To understand ambitious policy approaches, "relatively successful" cities are regularly subject of analyses. This paper also focuses on relatively successful cities - by reviewing the application documents of the winner cities of the European Green Capital Award (EGCA). Award schemes not only aim to reward leading participants, but likewise aim to contribute to knowledge transfer and the dissemination of good practice examples to non-participants. So far award schemes and good practice approaches have received limited attention by research. This paper reviews and analyses the application forms of the EGCA winning cities to learn about ambitious policy approaches to sustainable and climate-friendly urban transport.

Businesses like Airbnb have shown that a successful circular economy (CE) business can operate exclusively online. Although online communication and web appearance attributes have been subject to academic research given accelerated digitization, there is still a lack of knowledge about online attributes and their role in facilitating CE. We close the portrayed knowledge gap by conducting a discrete-choice experiment with best to worst scaling and focusing on the effect of CE experience on the perception of a CE website by ranking nine online attributes, grouped in three subsets. We therefore contribute by identifying online attributes that are perceived as favorable for CE businesses and detect how participation in CE activities affects the perception of these attributes. We find that third-party associated online attributes (e.g., user reviews or third-party guarantees) rank significantly higher throughout CE consumption patterns of the sample, being always amongst the top three attributes. This novel finding on online preferences opens a new direction for further research, as well as allows practitioners to optimize online operations accordingly. Furthermore, we find that users without prior touchpoints with CE have a higher need for information about the business model as compared to CE active users who are more interested in community related attributes.

Participatory modeling - the involvement of stakeholders in the modeling process - can support various objectives, such as stimulating learning processes or promoting mutual understanding of stakeholders. Participatory modeling approaches could therefore be useful for the governance of transitions, but a systematic account of potential application areas of participatory modeling methods in transition governance is still lacking. This article addresses this gap by providing a review of participatory modeling methods and linking them to phases and objectives of transition governance. We reviewed participatory modeling studies in transition research and related fields of social-ecological modeling, integrated assessment and environmental management. We find that participatory modeling methods are mostly used for participatory visioning and goal setting as well as for interactive strategy development. The review shows the potential for extending the application of participatory modeling methods to additional phases of transition governance and for the exchange of experiences between research fields.

Every diet has an impact on an individual’s health status, the environment, as well as on social concerns. A growing number of meals are consumed in the out-of-home catering sector, in which a systematic sustainability assessment is not part of common practice. In order to close this gap, an instrument was developed as part of the NAHGAST project. After more than one year of using the NAHGAST online tool, it needs to be assessed what positive environmental influences can be realized by using the tool. For this reason, this article deals with the question of whether an online tool can enable stakeholders from the out-of-home consumption sector to revise their meals with regard to aspects of a sustainable diet. In addition, it will be answered how precise recipe revisions of the most popular lunchtime meals influence the material footprint as well as the carbon footprint. In conclusion, an online tool can illustrate individual sustainability paths for stakeholders in the out-of-home consumption sector and enables an independent recipe revision for already existing meals. The results show that even slight changes in recipes could lead to savings of up to a third in carbon footprint as well as in material footprint. In relation to the out-of-home consumption sector, this results in the potential for substantial multiplication effects that will pave the way for the dissemination of sustainable nutrition.

Climate researchers agree that anthropogenic greenhouse gas emissions significantly contribute to climate change, and that radical measures to reduce greenhouse gas emissions and to adapt to the impacts of no longer avoidable climate change are needed. The German Federal Government with its Climate Protection Plan 2050 reinforced its target to reduce Germany's greenhouse gas emissions by 80 to 95 percent compared with 1990. The achievement of these targets requires nothing less than a fundamental transformation of spatial planning. In the paper a methodology to scientifically assess the likely impacts of possible combinations of policies or strategies to achieve the energy transition, i.e. to reduce the greenhouse gas emissions of urban mobility and transport is proposed and demonstrated, using the Ruhr Area, the largest conurbation in Germany, as an example. The results of the policies examined so far can be summarised as follows: Push measures as high energy prices, speed limits or reduction of the number of lanes of main roads are more effective in reducing greenhouse gas emissions than pull measures as the promotion of cycling, walking, electric cars or public transport. Between policies or policy packages there can be positive or negative synergies, i.e. the impacts of measures can reinforce or weaken each other. The results show that even with ambitious policies the greenhouse gas emission targets of the national and state governments will not be achieved and that more radical policies are needed.

Addressing the prevailing mode of high-carbon lifestyles is crucial for the transition towards a net-zero carbon society. Existing studies fail to fully investigate the underlining factors of unsustainable lifestyles beyond individual determinants nor consider the gaps between current footprints and reduction targets. This study examines latent lifestyle factors related to carbon footprints and analyzes gaps between decarbonization targets and current lifestyles of major consumer segments through exploratory factor analysis and cluster analysis. As a case study on Japanese households, it estimates carbon footprints of over 47,000 households using expenditure survey microdata, and identifies high-carbon lifestyle factors and consumer segments by multivariate regression analysis, factor analysis, and cluster analysis. Income, savings, family composition, house size and type, ownership of durables and automobiles, and work style were confirmed as determinants of high-footprint Japanese households, with eight lifestyles factors, including long-distance leisure, materialistic consumption, and meat-rich diets, identified as the main contributory factors. The study revealed a five-fold difference between lowest and highest footprint segments, with all segments overshooting the 2030 and 2050 decarbonization targets. The findings imply the urgent need for policies tailored to diverse consumer segments and to address the underlying causes of high-carbon lifestyles especially of high-carbon segments.