Micro Housing: No Contribution to Affordable Housing – a Berlin Case Study

The limited body of research on micro housing, which refers to small-scale housing units for single-person households, often associates this with housing affordability. In this study, we analyse the affordability of micro housing based on housing advertisements using Berlin as case study area. Therefore, we focus on different target groups of micro housing named by industry-driven research. On the one hand, we argue that the relevance of some of these groups for housing affordability from anurban development planning perspective is questionable. On the other hand, the results indicate that micro units are hardly affordable for target groups such as students, who are often affected by housing affordability problems. Our study illustrates that for Berlin there is a substantial mismatch between the potential contribution postulated in literature and the actual contribution of micro units to affordable housin

Analysis of limiting factors for Li-Ion battery performance and life-time: Micro-structure resolved simulations with BEST

In our presentation we will show examples of micro-structure resolved simulations in our battery simulation tool BEST (Battery and Electrochemistry Simulation Tool [1]). BEST was originally developed for the simulation of Li-Ion batteries in the former group of one of the authors (AL) at the Fraunhofer ITWM Kaiserslautern. The governing equations are derived in a rigorous approach from fundamental non-equilibrium thermodynamics and are implemented based on the CoRheos framework for complex and granular flow. DLR/HIU and Fraunhofer ITWM are collaborating to develop models for additional physical and chemical processes as well as new battery chemistries and to implement them in the software package. BEST is under constant active development and gives insights to fundamental physical processes as well as the latest developments for state-of-the-art battery materials. Li-Ion batteries are commonly used in portable electronic devices due to their outstanding energy and power density. Remaining issues which hinder a breakthrough e.g. for stationary storage applications or electric vehicles are high production costs as well as safety risks. Recently, new battery concepts with thicker electrodes (>300 µm) or solid electrolytes were suggested to resolve these issues [2]. In both cases mass and charge transport limitations can be severe at already small currents due to long transport pathways, small transport coefficients, or inhomogeneous material properties. This could be a trigger for degradation effects, such as Li plating at the graphite anode, and reduces the lifetime of the battery. A thorough understanding of relevant processes within the electrodes is urgently needed to avoid these problems. The electrode micro-structures of our simulations are either taken from tomography data [3] or geometries generated in GeoDict. Our detailed 3D studies allow important insights on cell operation and reveal detrimental structural properties for battery performance. For instance, we are able to quantify the effect of an inhomogeneous distribution of conductive additive in the case of thick electrodes or imperfect impregnation of the electrodes with the solid electrolyte. Moreover, we investigate the occurrence of degradation processes, such as Li plating during battery charge. Our approach allows analyzing limiting processes and critical operation conditions and predicts possible optimization and operation strategies to improve the performance and life-time of Li-Ion batteries

Mikroapartments in Deutschland - eine Analyse räumlicher Implikationen von Mikroapartmentanlagen

Eine nachhaltige Stadtentwicklung erfordert die nachhaltige Entwicklung des Wohnungsbestandes. Als wichtigen Baustein auf dem Weg dahin empfiehlt beispielsweise die "Kommission für nachhaltiges Bauen am Umweltbundesamt", eine Reduzierung der Pro-Kopf-Wohnfläche anzustreben sowie suffiziente Grundrisslösungen zu entwickeln. In diesem Sinne sind Mikroapartments als flächenreduzierte Wohneinheiten für Einpersonenhaushalte von besonderer Relevanz. Neben Klimaschutz und Ressourceneffizienz existieren aber weitere Ansprüche an nachhaltige urbane Räume, weswegen dieser Beitrag Mikroapartments im Kontext nachhaltiger Stadtentwicklung erforscht. Als konzeptioneller Rahmen wird der Ansatz einer raumbezogenen Wohnforschung erprobt. Ein zentrales Ergebnis der Untersuchung lautet, dass eine mögliche Belebung städtischer Nischenräume das wesentliche Potenzial von Mikroapartmentanlagen darstellt. Zur Bereitstellung bezahlbaren Wohnens für Studierende, die eine Zielgruppe von Mikroapartments bilden, tragen jene hingegen eher nicht bei. Verbleibende Wissenslücken zu sozialräumlichen Implikationen von Mikroapartments kann Forschung allerdings zur Frage, ob Wohnende vermehrt Tätigkeiten aus den Wohneinheiten auslagern, schließen.Sustainable urban development requires the sustainable development of the housing sector. The Commission for Sustainable Building at the German Environment Agency, for example, recommends a reduction in per capita living space and developing sufficient floor plan designs. In this sense, micro-apartments are of particular relevance. Aside from climate change mitigation and resource efficiency, the are other challenges to sustainable urban spaces which have to be considered. To this end, this paper researches micro-apartments in the context of sustainable urban development planning. As a conceptual framework, the approach of a more space-oriented housing research is tested. A possible revitalisation of urban niches is identified as the main potential of micro-apartment complexes. However, we find micro-apartments do not contribute to affordable housing for students, who are a main target group of micro-apartments. Further research on whether tenants of micro-apartments are increasingly outsourcing housing-related activities is needed, so that the socio-spatial implications of micro-apartments can be better understood