Description: This paper analyses and compares industry sector transformation strategies as envisioned in recent German, European and global deep decarbonisation scenarios. The first part of the paper identifies and categorises ten key strategies for deep emission reductions in the industry sector. These ten key strategies are energy efficiency, direct electrification, use of climateneutral hydrogen and/or synthetic fuels, use of biomass, use of CCS, use of CCU, increases in material efficiency, circular economy, material substitution and end-use demand reductions. The second part of the paper presents a meta-analysis of selected scenarios, focusing on the question of which scenario relies to what extent on the respective mitigation strategies. The key findings of the meta-analysis are discussed, with an emphasis on identifying those strategies that are commonly pursued in all or the vast majority of the scenarios and those strategies that are only pursued in a limited number of the scenarios. Possible reasons for differences in the choice of strategies are investigated. The paper concludes by deriving key insights from the analysis, including identifying the main uncertainties that are still apparent with regard to the future steps necessary to achieve deep emission reductions in the industry sector and how future research can address these uncertainties.

Description: Since human nutrition is responsible for about 30 % of the global natural resource use and in order to decrease resource use to a level in line with planetary boundaries, Lukas et al. (2016) proposed a re-source use reduction in the nutrition sector by a factor 2 (Material Footprint). The catering sector needs clearly defined indicators to assess their business activities' impact on ecology, social aspects, economic value, and health status. Within the project NAHGAST two sets of indicators, called NAHGAST Meal-Basis and NAHGAST Meal-Pro were developed. The indicator sets are proposed to measure several, with sustainability-associated challenges, such as such as the ecological, social and economical effects, which may come along with the production and the consumption of a meal. Basically, the NAHGAST Meal-Basis deals with qualitative indicators, such as the amount of organic food per serving or the percentage of food wasted. This set is supposed to enable leaders to assess the sustainability of their meals and to visualize future improvements on a simplistic level. The NAHGAST Meal-Pro deals with a more sophisticated set of indicators, such as the carbon and material footprint or the cost recovery per meal. Both sets are underpinned with sus-tainable targets and elaborated as an Excel-based assessment tool, which is tested within a one-year case study. The usefulness and the limits of the tool, as well as current results of the implementation including pro-posed challenges, are discussed.

Description: In 2008, transport accounted for 27% of the world’s total final energy consumption. Currently, we are facing a rapidly expanding transport sector with continually increasing energy consumption. In the future, emerging and developing countries especially will experience an accelerated growth in transport energy demand due to rapid population growth, urbanisation and rising per capita income. The transport sector’s inefficiency and its dependency on oil will become an economic burden for these countries. They will have to face increasing crude oil prices and uncertainties regarding energy security. Thus, there is a need for an efficient transport system and particularly for decision makers in developing and emerging countries to have access to planning advice in order to identify suitable and effective measures for low-energy urban transport. To meet this demand, existing knowledge and measures about energy efficiency in urban passenger transport was compiled and a structured introduction to energy efficiency in transport is provided. The main determinates of an energy-efficient transport system are explained and strategic approaches to increase energy efficiency are outlined. Success factors and barriers for energy efficiency policies are described. The main element of the paper is an overview of different energy efficiency policies and measures for the key actors in energy-efficient transport on local and national levels. A set of measures is assigned to each actor identified. The compilation was adapted to the circumstances in developing and emerging countries and includes examples for successful implementation of several measures. Thus, the document satisfies the need for a comprehensive introduction to energy efficiency in urban transport in developing and emerging countries.

Description: Climate change and thus low-carbon transitions are global challenges, which require commitment and effort on all political levels. As international climate politics has approached its limits over the last two decades, the role of cities has simultaneously gained in importance. Many cities1 worldwide have committed to ambitious climate protection targets, which often exceed national targets. However, cities cannot act in isolation. Their opportunities for action are embedded in an (inter)national policy framework, which may either support or hinder local actions. This gives rise to the question: which opportunities for climate protection do cities really have in a political system of multi-level governance? This question can be illustrated using the city of Hamburg as an example for the German climate policy regime. The city aims to reduce its annual CO2 emissions by 2 million metric tons and attempts to quantify the impact of local and national policies and actions using a bottom-up monitoring approach. We therefore analyse more than 400 local actions with respect to the induced CO2 emission reductions. We also take a closer look at national and European policies and their impacts on local energy use and emissions. In total, 15 policies and instruments - broadly ranging from instruments to foster energy efficiencyin residential and non-residential buildings, in appliances and in the transport sector, to support renewable energy sources (including biofuels) and to uptake CHP - are considered. Our approach consists in measuring separately the impact of local and national policies and actions on urban CO2 emissions. While the city of Hamburg has implemented many policies and actions, our results show that, a significant proportion of its CO2 reduction is due to national policies, in the context of the German "Energiewende", which cannot or can only indirectly be influenced by the city. The results imply that local commitment and effort is essential in addressing the global challenge, yet ambitious targets can only be met in the presence of a supportive national policy framework. The analysis shows that many policies and measures implemented at national level require supportive structures and activities at local level in order to bridge information and implementation gaps of these measures.

Description: The role of cities in mitigating GHG emissions and thus tackling global warming has gained importance over the last years.Many cities have developed climate action plans, primarily to achieve long-term "low-carbon" mitigation goals set by national governments or (inter)national agreements. A mere adoption of high level targets, however, raises the question whether these targets are applicable for cities with very different framework conditions. We argue that it is crucial to understand the socio-economic, geophysical, spatial, infrastructural and political framework of a city - a broad approach, which is generally missing in climate action plans. Thus, determining drivers and barriers for future development paths is neglected by local policies, which leads to a gap between ambition (target) and reality (implementation). We exemplarily examine this hypothesis for the shrinking city of Oberhausen (Germany). Oberhausen, located in the Ruhr area,is a typical old industrial region, which has seen a decline of its industrial basis over the last decades. We analysed historical data and developed scenarios until 2030. Both show a significant decrease in CO2 emissions. A closer look, however, reveals that the reduction is primarily due to the economic transformation (less manufacturing, more service industry, accompanied by a decrease in population) and general energy efficiency developments following the implementation of national and EU policies. Although the city has implemented–and will further implement - many instruments and policies to reduce CO2 emissions, local barriers such as unemployment, low rents, low income, high per capita debts, etc. dramatically reduce the city's capacity for action. The results show that Oberhausen's emission reductions do not reflect active energy policies but are mainly driven by an economic decline. To reach ambitious reduction targets, however, the city needs to be enabled to take action in achieving appropriate and reasonable targets.

Description: Human nutrition is responsible for about 30% of the global natural resource use. In order to decrease resource use to a level in line with planetary boundaries, a resource use reduction in the nutrition sector by a factor 2 is suggested. A large untapped potential to increase resource efficiency and improve consumers' health status is assumed, but valid indicators and general guidelines to assess these impacts and limits can barely be found. Therefore we will have a try to define sustainable limits towards the individuals' daily diet and therefore stimulate current available scientific debate. Within the paper an examination of existing indicators and assessment methods is carried out. We set the focus on health indicators, such as energy intake, and environmental indicators, such as the carbon or material footprint. The paper aims to provide first, an assessment of core indicators to explore the sustainability impact of foodstuff, and second, a deeper understanding and a discussion of sustainable limits for those dimensions of food and nutrition. Therefore we will discuss several ecological and health indicators which may be suitable to assess the sustainabilty impact and indicate differences or similarities. As a result it becomes obvious that several ecological indicators "point in the same direction" and therefore a discussion about the variability and the variety of these indicators has to be faced in the future. Further the definition of sustainable levels per indicator is an essential aspect to get an idea about the needed barriers for a sustainable nutrition, by now first steps had been made, but no binding guidelines are available yet. Therefore the paper suggests a few indications to set up sustainable levels for health and environmental indicators, based on the idea to reduce the resource use level up to 30-50% in 2030.

Description: The unprecedented challenge of reaching carbon neutrality before mid-century and a large share of it within 2030 in order to keep under the 1.5 or 2 °C carbon budgets, requires broad and deep changes in production and consumption patterns which, together with a shift to renewables and reinforced efficiency, need to be addressed through energy sufficiency. However, inadequate representations and obstacles to characterising and identifying sufficiency potentials often lead to an underrepresentation of sufficiency in models, scenarios and policies. One way to tackle this issue is to work on the development of sufficiency assumptions at a concrete level where various implications such as social consequences, environmental co-benefits, conditions for implementation can be discussed. This approach has been developed as the backbone of a collaborative project, gathering partners in 20 European countries at present, aiming for the integration of harmonised national scenarios into an ambitious net-zero European vision. The approach combines a qualitative discussion on the role of energy sufficiency in a "systemic" merit order for global sustainability, and a quantitative discussion of the level of sufficiency to be set to contribute to meeting 100 % renewables supply and net-zero emissions goals by 2050 at the latest. The latter is based on the use of a dashboard, which serves as a common descriptive framework for all national scenario trajectories and their comparison, with a view to harmonising and strengthening them through an iterative process. A set of key sufficiency-related indicators have been selected to be included in the dashboard, while various interrelated infrastructural, economic, environmental, social or legal factors or drivers have been identified and mapped. This paves the way for strengthening assumptions through the elaboration of "sufficiency corridors" defining a convergent, acceptable and sustainable level of energy services in Europe. The process will eventually inform the potential for sufficiency policies through a better identification of leverages, impacts and co-benefits.

Description: Sustainable out-of-home nutrition can help achieve overarching sustainability goals through a transformation in demands of consumers in this growing market. Studies indicate that individual food choice behaviours in out-of-home settings relate to a wide set of personal, social and situational factors. These factors can be influenced by various intervention strategies. In an expert meeting and a focus group we invited caterers and consumers to generate, discuss and evaluate various practical intervention ideas. Both parties largely perceive the explored ideas as useful and agree on key intervention ideas. Overall caterers and consumers state to prefer nudging strategies over information and participation interventions.

Description: The concept of sufficiency - reducing energy uses beyond technical efficiency - is far-reaching and requires a reflection on human needs, energy services, urban structures, social norms, and the role of policies to support the shift towards lower-energy societies. In recent years, a growing body of literature has been published on energy sufficiency in various disciplines. However, there has been limited exchanges and cooperation among researchers so far, hindering the visibility and impact of this research. This paper presents an assessment of where sufficiency research stands, especially in the perspective of policy-making. It is the first overview paper issued in the context of the newly-founded ENOUGH network - International network for sufficiency research & policy, established in 2017. In the first part, we provide a condensed literature review on energy sufficiency, based on dozens of recent references collected through the network. Through four main themes (the nature of sufficiency, the challenges of modelling it, the barriers to its diffusion, and the approaches to foster it), we summarise the key issues and approaches. We then present what the scholars themselves see as the priorities for future research, promising sufficiency policy options, and key barriers that research should help overcome. We collected their views through a questionnaire completed by more than 40 knowledgeable authors and experts from various disciplines. We finally build on the previous parts to draw some recommendations on how sufficiency research could increase its impact, notably in relation to policy-making.

Description: Technological innovations in energy-intensive industries (EIIs) have traditionally emerged within the boundaries of a specific sector. Now that these industries are facing the challenges of deep decarbonisation and a significant reduction in greenhouse gas (GHG) emissions is expected to be achieved across sectors, cross-industry collaboration is becoming increasingly relevant for low-carbon innovation. Accessing knowledge and other resources from other industrial sectors as well as co-developing innovative concepts around industrial symbiosis can be mutually beneficial in the search for fossil-free feedstocks and emissions reductions. In order to harness the potential of this type of innovation, it is important to understand not only the technical innovations themselves, but in particular the non-technical influencing factors that can drive the successful implementation of cross-industry collaborative innovation projects. The scientific state of the art does not provide much insight into this particular area of research. Therefore, this paper builds on three separate strands of innovation theory (cross-industry innovation, low-carbon innovation and innovation in EIIs) and takes an explorative case-study approach to identify key influencing factors for cross-industry collaboration for low-carbon innovation in EIIs. For this purpose, a broad empirical database built within the European joint research project REINVENT is analysed. The results from this project provide deep insights into the dynamics of low-carbon innovation projects of selected EIIs. Furthermore, the paper draws on insights from the research project SCI4Climate.NRW. This project serves as the scientific competence centre for IN4Climate.NRW, a unique initiative formed by politicians, industry and science to promote, among other activities, cross-industry collaboration for the implementation of a climate-neutral industry in the German federal state of North Rhine-Westphalia (NRW). Based on the results of the case study analysis, five key influencing factors are identified that drive the implementation of cross-industry collaboration for low-carbon innovation in EIIs: Cross-industry innovation projects benefit from institutionalised cross-industry exchange and professional project management and coordination. Identifying opportunities for regional integration as well as the mitigation of financial risk can also foster collaboration. Lastly, clear political framework conditions across industrial sectors are a key driver.