One of the most pressing issues of climate policy is how to get building owners to invest in the energy efficiency of their homes. The German federal government has set the goal of decreasing the energy demand of buildings by 80 to 95 percent until 2050. One pillar of the strategy to support building owners in this task is the provision of targeted energy advice, to both motivate owners to implement an energy efficiency refurbishment and help them to choose the most efficient measures. In this paper we analysed the demand for energy advice in three German cities of the Ruhr area finding the number of energy consulting provided to be extremely low compared to the stated goals. Based on the approach of joint knowledge production we invited stakeholders from the three cities to participate in a series of workshops in order to develop ideas how to more effectively bring homeowners and energy advisors together. As a result, different energy advice experiments were co-operatively developed for each city targeting different groups by using tailored channels for outreach. The evaluation of both the process as well as the outcome of the experiments indicates that while joint knowledge production is a suitable approach to enable knowledge transfer and formation of new networks between different stakeholders in science and practice, it does not necessarily lead to superior approaches with regard to effectively addressing a policy issue at hand. Apart from the experiment in which the window of opportunity change of building ownership was taken advantage of, participation of target groups in the experiments has been soberingly low, underlining the value of so-called trigger points when designing effective outreach strategies to building owners.
Food labels are able to support consumers in making more sustainable food choices in out-of-home consumption situations. Thereby, the effect of changing consumption behaviour depends on the format of food labels and on the information it provides. In order to assess the importance of the amount of information as well as the design of food labels displaying sustainability aspects, we test different formats of food labels using a best-worst choice design. So far, no research tested a variation of information depth while keeping label designs fixed. We find clear preferences across both dimensions. Results indicate that consumers regard labels with a higher information depth as more helpful in order to choose a sustainable meal. For the label design it became obvious that the slider-design is preferred over footprints and traffic light label design.
Following the decisions of the Paris climate conference at the end of 2015 as well as similar announcements e.g. from the G7 in Elmau (Germany) in the summer of 2015, long-term strategies aiming at (almost) full decarbonisation of the energy systems increasingly move into the focus of climate and energy policy. Deep decarbonisation obviously requires a complete switch of energy supply towards zero GHG emission sources, such as renewable energy. A large number of both global as well as national climate change mitigation scenarios emphasize that energy efficiency will likewise play a key role in achieving deep decarbonization. However, the interdependencies between a transformation of energy supply on the one hand and the role of and prospects for energy efficiency on the other hand are rarely explored in detail.
This article explores these interdependencies based on a scenario for Germany that describes a future energy system relying entirely on renewable energy sources. Our analysis emphasizes that generally, considerable energy efficiency improvements on the demand side are required in order to have a realistic chance of transforming the German energy system towards 100 % renewables. Efficiency improvements are especially important if energy demand sectors will continue to require large amounts of liquid and gaseous fuels, as the production of these fuels are associated with considerable energy losses in a 100 % renewables future. Energy efficiency on the supply side will therefore differ considerably depending on how strongly the use of liquid and gaseous fuels in the various demand sectors can be substituted through the direct use of electricity. Apart from a general discussion of the role of energy efficiency in a 100 % renewable future, we also look at the role of and prospects for energy efficiency in each individual demand sector.
Energy sufficiency has recently gained increasing attention as a way to limit and reduce total energy consumption of households and overall. This paper presents selected results of a research project funded by the German Federal Ministry of Education and Research that examined the potentials and barriers for energy sufficiency with a focus on electricity in households, how household members perceive sufficiency practices, and how policymakers could support and encourage these. Bottom-up calculations for an average 2-person household in Germany yielded a total electricity savings potential from energy efficiency and sufficiency combined of theoretically up to 75 %.
The continuous growth of per capita living space was identified as one important driver for additional energy consumption both for heat and electricity. The paper will present findings of a representative survey of 600 persons responsible for the housework. It revealed that a part of the households is already practicing sufficiency options or are open towards these. Up to 30 % of these households can imagine, given the right conditions and policy support, to move to a smaller dwelling or to share an apartment with others when they are older.
Results of a first comprehensive analysis of an energy sufficiency policy to encourage and support households to sufficiency practices form the second part of the paper, with a focus on the feasibility and potential effectiveness of instruments for limiting the growth in average living space per person. This includes a case study on fostering communal housing projects as a measure to reduce living space. Further, the feasibility of a cap scheme for the total electricity sales of a supplier to its customers was examined. Instruments supporting energy-efficient and sufficient purchase and use of equipment complete the integrated energy sufficiency and efficiency policy package.
The paper will finally present the project's conclusions on an integrated energy sufficiency policy package resulting from this analysis.
Contemporary combined heat and power (CHP) systems are often based on fossil fuels, such as natural gas or heating oil. Thereby, small-scale cogeneration systems are intended to replace or complement traditional heating equipment in residential buildings. In addition to space heating or domestic hot water supply, electricity is generated for the own consumption of the building or to be sold to the electric power grid.
The adaptation of CHP-systems to renewable energy sources, such as solid biomass applications is challenging, because of feedstock composition and heat integration. Nevertheless, in particular smallscale CHP technologies based on biomass gasification and solid oxide fuel cells (SOFCs) offer significant potentials, also regarding important co-benefits, such as security of energy supply as well as emission reductions in terms of greenhouse gases or air pollutants. Besides emission or air quality regulations, the development of CHP technologies for clean on-site small-scale power generation is also strongly incentivised by energy efficiency policies for residential appliances, such as e.g. Ecodesign and Energy Labelling in the European Union (EU). Furthermore, solid residual biomass as renewable local energy source is best suited for decentralised operations such as micro-grids, also to reduce long-haul fuel transports. By this means such distributed energy resource technology can become an essential part of a forward-looking strategy for net zero energy or even smart plus energy buildings.
In this context, this paper presents preliminary impact assessment results and most recent environmental considerations from the EU Horizon 2020 project "FlexiFuel-SOFC" (Grant Agreement no. 641229), which aims at the development of a novel CHP system, consisting of a fuel flexible smallscale fixed-bed updraft gasifier technology, a compact gas cleaning concept and an SOFC for electricity generation. Besides sole system efficiencies, in particular resource and emission aspects of solid fuel combustion and net electricity effects need to be considered. The latter means that vastly less emission intensive gasifier-fuel cell CHP technologies cause significant less fuel related emissions than traditional heating systems, an effect which is further strengthened by avoided emissions from more emission intensive traditional grid electricity generation. As promising result, operation "net" emissions of such on-site generation installations may be virtually zero or even negative. Additionally, this paper scopes central regulatory instruments for small-scale CHP systems in the EU to discuss ways to improve the framework for system deployment.
Bei der Energiewende handelt es sich um einen komplexen Transformationsprozess, der nicht allein aus der nationalen Perspektive betrachtet werden kann. Er ist nicht vollständig unabhängig, sondern in einen Mehr-Ebenen-Prozess eingebunden. Es gilt entsprechend sowohl lokale als auch regionale, nationale, europäische und auch die internationalen Energiewendeprozesse und zugehörigen Rahmenbedingungen zu diskutieren und zu beachten. Es gilt aber auch, über den eigentlichen Energiebereich hinausgehende Trends in ihren Wechselwirkungen mit dem Energiesystem zu identifizieren und zu analysieren. Mit der Energiewende wird zudem eine Zielvielfalt angesprochen. Es geht über das Erreichen von Klimaschutzzielen hinaus um eine größere Vielfalt von gesellschaftlich-politischen Zielen.
Der Transformationsprozess hat keine eindimensionale Zielorientierung, sondern muss in einer mehrdimensionalen Betrachtung analysiert werden.
In recent years, many energy scenario studies have proven that a power supply system based on renewable energies (RE) >90 percent is feasible. However, existing scenarios differ significantly in the composition of generation technologies. Some scenarios focus on wind energy in the northern part of Europe, others base on a large utilisation of solar technologies in the south. Apart from the generation capacities, the needed technical flexibilisation strategies such as grid extension, demand flexibilisation and energy storage are generally known and considered in many scenarios. Yet, the impact of different renewable generation strategies on the local utilisation of flexibility options needs to be further assessed. Based upon the BMBF research project RESTORE2050, analyses have been carried out that focus on these interdependencies. The results of the project show that the local utilisation of flexibilisation options depends to a great extent on the technology focus of the long-term renewable expansion strategy. This applies for the spatial flexibilisation as provided by transnational interconnection capacities, especially the ones connecting regions with a surplus of power generation (e.g. GB, Norway and Spain). Another impact of the renewable scenario is seen on the required temporal flexibilisation of electricity generation and demand. In addition, the available options will compete for high utilisation in a future energy system. The differences in the utilisation of these applications, which base on the varying shares of photovoltaic (PV) and wind energy generation, lead to the conclusion that the decision about longterm RE expansion ought to be made very soon in order to avoid inefficient flexibility pathways. Otherwise, if the future RE structure will be kept open, adequate adoption of new flexibility options will be difficult, especially in case of technologies with long lead and realisation time (e.g. new power grids and large scale energy storage devices).
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.