Diesen Technologien wird für das Energiesystem, bei einem zunehmenden Ausbau der fluktuierenden regenerativen Leitenergieträger Wind und Sonneneinstrahlung als zentrale Flexibilitätsoption sowie zur Dekarbonisierung der Industrie - Bereitstellung von Wasserstoff und Kohlenwasserstoffen -, eine Schlüsselrolle zukommen. Wie die bisherigen Erfahrungen mit anderen Energieinfrastrukturen, z. B. Freileitungen oder Windkraftanlagen, zeigen, stellt eine breite gesellschaftliche Akzeptanz einen wesentlichen Erfolgsfaktor für die großflächige Diffusion und Transformation dar. Entsprechend ist die gesellschaftliche Einbettung auch bei der Planung von PtX-Strategien frühzeitig zu beachten.
Unter den Stichworten "Sektorenkopplung" und "Power-to-X" werden derzeit viele Möglichkeiten der direkten und indirekten Elektrifizierung großer Teile der Endenergienachfrage intensiv diskutiert. In diesem Zusammenhang hat die Diskussion um Wasserstoff als Endenergieträger sowie als Feedstock für die Herstellung von synthetischen Kraftstoffen und chemischen Grundstoffen zuletzt stark an Bedeutung gewonnen. Insbesondere der klimaneutrale Umbau der Grundstoffindustrien und hier vor allem der Grundstoffchemie und der Stahlindustrie würde bedeutende Mengen an grünem Wasserstoff benötigen, die räumlich stark auf die großen Industriekerne fokussiert wären. Ein zeitnaher Einstieg in die Schaffung entsprechender Erzeugungskapazitäten und Infrastrukturen könnte dazu führen, dass Wasserstoff - neben erneuerbaren Energien und Energieeffizienz - zum dritten Standbein der Energiewende avanciert.
In vielen deutschen Städten sinken die verkehrsbedingten CO2-Emissionen kaum und vor allem die Belastungen durch Luftschadstoffe aus dem Straßenverkehr sind weiterhin sehr hoch. Deshalb beklagt die Deutsche Umwelthilfe inzwischen über 30 Städte in Deutschland, um durch Fahrverbote für Dieselfahrzeuge das Recht der Menschen auf saubere Atemluft durchzusetzen. Daher suchen die Kommunen zunehmend Wege, die verkehrsbedingten Emissionen zu senken. Dabei kommt kommunalen Flottenbetreibern eine besondere Rolle zu. Sie stehen besonders unter Handlungsdruck, weil durch ein Fahrverbot für Dieselfahrzeuge diese nur noch sehr eingeschränkt eingesetzt werden könnten.
A significant reduction in greenhouse gas emissions will be necessary in the coming decades to enable the global community to avoid the most dangerous consequences of man-made global warming. This fact is reflected in Germany's 7th Federal Energy Research Program (EFP), which was adopted in 2018. Direct Air Capture (DAC) technologies used to absorb carbon dioxide (CO2) from the atmosphere comprise one way to achieve these reductions in greenhouse gases. DAC has been identified as a technology (group) for which there are still major technology gaps. The intention of this article is to explore the potential role of DAC for the EFP by using a multi-dimensional analysis showing the technology's possible contributions to the German government's energy and climate policy goals and to German industry's global reputation in the field of modern energy technologies, as well as the possibilities of integrating DAC into the existing energy system. The results show that the future role of DAC is affected by a variety of uncertainty factors. The technology is still in an early stage of development and has yet to prove its large-scale technical feasibility, as well as its economic viability. The results of the multi-dimensional evaluation, as well as the need for further technological development, integrated assessment, and systems-level analyses, justify the inclusion of DAC technology in national energy research programs like the EFP.
This paper offers a comparative analysis of small wind electrification programmes targeted at remote sheep farming households in two of the windiest regions of the world, Argentine Patagonia and the Falkland Islands/Islas Malvinas. Despite comparable environmental conditions and local livelihoods, their impact was vastly different. Insights from socio-technical systems and strategic niche management approaches offered a deeper understanding of the local context and development dynamics, facilitating the identification of the critical success factors that contributed to these two distinct outcomes and finally highlighting those that can inform the design of future such initiatives. The research is based upon a series of semi-structured interviews with key stakeholders, observational field visits and review of archival sources. The critical factors identified by this case study research include strong and consistent institutional support, investment in robust equipment creation of effective feedback loops from the field and hybridisation. Additionally, a user centred approach that assesses whether small wind is really the right option for each individual household and if so, matches an appropriate energy system to their unique and evolving needs. Finally, empowering users to take on as much responsibility for maintenance as possible by integrating maintenance practices with local culture and ensuring the support of an effective decentralised maintenance network.
Responsible consumption and production is one of the Sustainable Development Goals of the United Nations. To achieve this goal the currently high extraction rates of natural resources, that our economy is based on, needs a transformation of the consumption and production system considering technological as well as social change. One of the promising transition approaches is seen in collaborative consumption with its many facets of socio-cultural innovations and fast growing number of participants and businesses. With a decreasing production of goods, due to a utilisation of underutilised assets, these offers might support an absolute reduction of the global resource use. However, a positive environmental effect depends on the setting and the social practices of such sharing offers and is not sustainable or resource efficient generally. Also, resource efficient practices with a low diffusion potential that stick in a niche offer no leverage to achieve sustainable consumption patterns. Thus, this paper describes a mixed method approach to analyse the resource efficiency and diffusion potential of 20 sharing offers in the area of mobility, housing & travel and everyday objects in Germany. Results show that the overall positive environmental connotation of sharing offers cannot be confirmed. We identified five clusters of offers that are all treated to be differently when it comes to deploying the positive potential and avoid unnecessary societal effort to achieve the mentioned Sustainable Development Goal.
In recent years, most countries in the Middle East and North Africa (MENA), including Jordan, Morocco and Tunisia, have rolled out national policies with the goal of decarbonising their economies. Energy policy goals in these countries have been characterised by expanding the deployment of renewable energy technologies in the electricity mix in the medium term (i.e., until 2030). This tacitly signals a transformation of socio-technical systems by 2030 and beyond. Nevertheless, how these policy objectives actually translate into future scenarios that can also take into account a long-term perspective up to 2050 and correspond to local preferences remains largely understudied. This paper aims to fill this gap by identifying the most widely preferred long-term electricity scenarios for Jordan, Morocco and Tunisia. During a series of two-day workshops (one in each country), the research team, along with local stakeholders, adopted a participatory approach to develop multiple 2050 electricity scenarios, which enabled electricity pathways to be modelled using Renewable Energy Pathway Simulation System GIS (renpassG!S). We subsequently used the Analytical Hierarchy Process (AHP) within a Multi-Criteria Analysis (MCA) to capture local preferences. The empirical findings show that local stakeholders in all three countries preferred electricity scenarios mainly or even exclusively based on renewables. The findings demonstrate a clear preference for renewable energies and show that useful insights can be generated using participatory approaches to energy planning.
Nowadays, the main impetus to apply additive manufacturing (AM) of metals is the high geometric flexibility of the processes and its ability to produce pilot or small batch series. In contrast, resource and energy intensities are often not considered as constraints, even though the turnout of additive manufacturing is high, at least compared to chip removing processes.
The study at hand analyses the material characteristics and environmental impacts of a hose nozzle as an example of a commercial product of simple geometry. The production routes turning (conventional manufacturing) and laser beam melting (additive manufacturing) are compared to each other in terms of natural resource use, climate change potential and primary energy demand. It is found, that the product shows a lower demand for natural resources when produced via AM, but higher carbon emissions and energy demand when using a steel, that is mainly (80%) produced from high-alloyed steel scrap. However, different case studies during the sensitivity analyses showed that a number of factors highly influence the results: the steel source as well as the source of electricity play a major role in determining the environmental performance of the production routes. The authors also found that other production processes (here cold forging of tubes) might be an eco-friendly alternative to both routes, if feasible from an economic point of view.
In regard to the material characteristics, experimental testing revealed that the material advantages of AM produced hose nozzles (in particular higher yield strength) are reduced after a solution heat treatment is applied to the as-produced material, in order to increase corrosion resistance. However, products that do not require this production step might benefit from the higher yield strength, as a lower wall thickness could be realised.
Urban energy systems have been commonly considered to be socio-technical systems within the boundaries of an urban area. However, recent literature challenges this notion in that it urges researchers to look at the wider interactions and influences of urban energy systems wherein the socio-technical sphere is expanded to political, environmental and economic realms as well. In addition to the inter-sectoral linkages, the diverse agents and multilevel governance trends of energy sustainability in the dynamic environment of cities make the urban energy landscape a complex one. There is a strong case then for establishing a new conceptualisation of urban energy systems that builds upon these contemporary understandings of such systems. We argue that the complex systems approach can be suitable for this. In this paper, we propose a pilot framework for understanding urban energy systems using complex systems theory as an integrating plane. We review the multiple streams of urban energy literature to identify the contemporary discussions and construct this framework that can serve as a common ontological understanding for the different scholarships studying urban energy systems. We conclude the paper by highlighting the ways in which the framework can serve some of the relevant communities.
To contribute to a better understanding of consumer food leftovers and to facilitate their reduction in out-of-home settings, our study analyzes the effects of two common intervention strategies for reducing leftovers in a holistic behavioral model. Based on a quasi-experimental baseline-intervention design, we analyzed how the display of information posters and the reduction of portion sizes take an effect on personal, social and environmental determinants in a structural equation model. Applying data from online surveys and observations among 880 guests (503 baseline, 377 intervention) during two weeks in a university canteen, the suggested model allows to assign effects from the two interventions on plate leftovers to specific changes in behavioral determinants. Portion size reductions for target dishes are found to relate to lower levels of plate waste based on conscious perception, represented in smaller portion size ratings. Effects from seeing information posters are found to base on changed personal attitudes, subjective norms and perceived behavioral control. However, depending on how an individual reacts to the information (by only making an effort to finish all food or by making an effort and additionally choosing a different dish in the canteen) there are opposite effects on these determinants and consequently also on plate leftovers. Overall, the differentiated results on intervention effects strongly support the benefits of more holistic and in-depth analyses of interventions to reduce plate leftovers and therefore to contribute to more sustainable food consumption in out-of-home settings.