Dr.-Ing.

Albrecht, Stefan

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Analysis and visualisation of large scale life cycle assessment results: A case study on an adaptive, multilayer membrane façade

2024-05-17 , Borschewski, David , Prenzel, Tobias Manuel , Albrecht, Stefan , Leistner, Philip

The importance of visualisations in context of life cycle assessment has been widely discussed and acknowledged in the literature. Especially with the increasing ability to process and create large-scale LCA results, visualisations are vital tools to not only analyse and interpret but also check and validate underlying datasets. Based on a dataset containing 1.25 million LCA results for all potential configurations within a defined parameter space, different visualisations and analysis methods were applied to identify hotspots, assess parameter sensitivity, gain insights to optimise environmental sustainability, and provide benchmarks for an adaptive, multilayer membrane façade. Box plots for the identification of hotspots, parameter sensitivity, and benchmarking, as well as colour-coded scatter plots, have proven to be incredibly versatile and effective for understanding the results and providing multiple perspectives to gain further insight. The ability to interact directly with interactive visualisation in order to identify and isolate specific areas of interest allows for a very efficient analysis of the relevant aspects of data. However, the usefulness of the proposed visualisations is not only dependant on the quality and characteristic of the underlying data but also on the objectives and scope of the study, as well as the intended medium illustrating the results.

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Life cycle assessment for early-stage process optimization of microbial biosurfactant production using kinetic models - a case study on mannosylerythritol lipids (MEL)

2024 , Bippus, Lars , Briem, Ann-Kathrin , Beck, Alexander , Zibek, Susanne , Albrecht, Stefan

Introduction: This study assesses the environmental impacts of mannosylerythritol lipids (MELs) production for process optimization using life cycle assessment (LCA). MELs are glycolipid-type microbial biosurfactants with many possible applications based on their surface-active properties. They are generally produced by fungi from the family of Ustilaginaceae via fermentation in aerated bioreactors. The aim of our work is to accompany the development of biotechnological products at an early stage to enable environmentally sustainable process optimization. Methods: This is done by identifying hotspots and potentials for improvement based on a reliable quantification of the environmental impacts. The production processes of MELs are evaluated in a cradle-to-gate approach using the Environmental Footprint (EF) 3.1 impact assessment method. The LCA model is based on upscaled experimental data for the fermentation and purification, assuming the production at a 10 m³ scale. In the case analyzed, MELs are produced from rapeseed oil and glucose, and purified by separation, solvent extraction, and chromatography. Results: The results of the LCA show that the provision of substrates is a major source of environmental impacts and accounts for 20% of the impacts on Climate Change and more than 70% in the categories Acidification and Eutrophication. Moreover, 33% of the impacts on Climate Change is caused by the energy requirements for aeration of the bioreactor, while purification accounts for 42% of the impacts respectively. For the purification, solvents are identified as the main contributors in most impact categories. Discussion: The results illustrate the potentials for process optimization to reduce the environmental impacts of substrate requirements, enhanced bioreactor aeration, and efficient solvent use in downstream processing. By a scenario analysis, considering both experimental adaptations and prospective variations of the process, the laboratory development can be supported with further findings and hence efficiently optimized towards environmental sustainability. Moreover, the presentation of kinetic LCA results over the fermentation duration shows a novel way of calculating and visualizing results that corresponds to the way of thinking of process engineers using established environmental indicators and a detailed system analysis. Altogether, this LCA study supports and demonstrates the potential for further improvements towards more environmentally friendly produced surfactants.

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Process-based life cycle assessment for the manufacturing of functional materials and printed electronics

2023-06-16 , Prenzel, Tobias Manuel , Gehring, Florian , Narres, Nicoletta , Fuhs, Franziska , Albrecht, Stefan

Printed electronics are a massively researched technology that is continuously developing new materials, processes, and applications. With the increasing interest in the technology, also the associated environmental impacts gain growing importance. Therefore, insights on processes for functional material production and device manufacturing in the domain of printed electronics are required to provide a solid data baseline for determining environmental impacts of printed electronic devices and in a subsequent step benchmark them against conventional electronics. The document at hand summarizes the outcomes of task T11.5 - Pilot line LCA from the publicly funded EU-project LEE-BED (grant agreement no. 814485). The main objectives of the work conducted in this specific work package are the information of material developers, pilot line operators and potential users of printed electronics on the environmental impacts resulting from different production technologies. This means that the manufactured products (demonstrators, end user products) are explicitly not focused on, even though data collection for production processes naturally cannot be performed completely independently of products. Within the project, the outcomes of this task are fed back to the phase 1 service - life cycle analysis, developed in WP3 and applied in WP9 and WP10 in the project duration.

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Shape Memory Polymer Foam for Autonomous Climate-Adaptive Building Envelopes

2022-12-15 , Walter, Mario , Lengsfeld, Kristin , Borschewski, David Sven , Albrecht, Stefan , Kölsch, Philipp , Pretsch, Thorsten , Krus, Martin , Lehmann-Brauns, Susanne

Reducing the continuously growing cooling energy demand of buildings is an important part of achieving global emission targets. Here, we present an innovative scenario of how the integration of a programmable material into a climate-adaptive building envelope (CABE) can create an energy-efficient thermal management system inherent to the material. This novel concept is based on a thermoresponsive shape memory polymer foam (SMP) and is designed to regulate the flow of ambient air through the building envelope in order to enable natural cooling of the structure. Hygrothermal simulation data obtained by the software WUFI® Plus indicate that significant cooling energy saving potential may be accessible with this type of concept. As a possible material basis for a corresponding adaptive element, a reactive foamed polyurethane-based SMP foam is proposed, which is capable of executing a thermoreversible shape change of more than 20% while having a suitable switching temperature range. Finally, the ecological impact of such a functional foam element is evaluated in detail as well as its influence on the overall balance of a façade construction by means of a life cycle assessment (LCA).

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Switchable Heat Pipes for Eco-Friendly Battery Cooling in Electric Vehicles: A Life Cycle Assessment

2024-02-17 , Illner, Maike , Thüsing, Kai , Nioac de Salles, Ana Claudia , Trettenhann, Anian , Albrecht, Stefan , Winkler, Markus

Battery thermal management systems (BTMSs) ensure that lithium-ion batteries (LIBs) in electric vehicles (EVs) are operated in an optimal temperature range to achieve high performance and reduce risks. A conventional BTMS operates either as an active system that uses forced air, water or immersion cooling, or as a complete passive system without any temperature control. Passive systems function without any active energy supply and are therefore economically and environmentally advantageous. However, today’s passive BTMSs have limited cooling performance, which additionally cannot be controlled. To overcome this issue, an innovative BTMS approach based on heat pipes with an integrated thermal switch, developed by the Fraunhofer Cluster of Excellence Programmable Materials (CPM), is presented in this paper. The suggested BTMS consists of switchable heat pipes which couple a passive fin-based cold plate with the battery cells. In cold state, the battery is insulated. If the switching temperature is reached, the heat pipes start working and conduct the battery heat to the cold plate where it is dissipated. The environmental benefits of this novel BTMS approach were then analysed with a Life Cycle Assessment (LCA). Here, a comparison is made between the suggested passive and an active BTMS. For the passive system, significantly lower environmental impacts were observed in nearly all impact categories assessed. It was identified as a technically promising and environmentally friendly approach for battery cooling in EVs of the compact class. Furthermore, the results show that passive BTMS in general are superior from an environmental point of view, due their energy self-sufficient nature

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Bringing light into the dark - Overview of environmental impacts of carbon fiber production and potential levers for reduction

2024 , Prenzel, Tobias Manuel , Hohmann, Andrea , Prescher, Tim , Angerer, Kerstin , Wehner, Daniel , Ilg, Robert , Reden, Tjark von , Drechsler, Klaus , Albrecht, Stefan

Carbon fibers (CFs) are a crucial material for lightweight structures with advanced mechanical performance. However, there is still a paucity of detailed understanding regarding the environmental impacts of production. Previously, mostly singled-out scenarios for CF production have been assessed, often based on scarce transparent inventory data. To expand the current knowledge and create a robust database for future evaluation, a life cycle assessment (LCA) was carried out. To this end, a detailed industry-approved LCI is published, which also proved plausible against the literature. Subsequently, based on a global scenario representing the market averages for precursor and CF production, the most relevant contributors to climate change (EF3.1 climate change, total) and the depletion of fossil energy carriers (EF3.1 resource use, fossil) were identified. The energy consumption in CF manufacturing was found to be responsible for 59% of the climate change and 48% of the fossil resource use. To enable a differentiated discussion of manufacturing locations and process energy consumption, 24 distinct scenarios were assessed. The findings demonstrate the significant dependence of the results on the scenarios’ boundary conditions: climate change ranges from 13.0 to 34.1 kg CO2 eq./kg CF and resource use from 262.3 to 497.9 MJ/kg CF. Through the investigated scenarios, the relevant reduction potentials were identified. The presented results help close an existing data gap for high-quality, regionalized, and technology-specific LCA results for the production of CF.

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Ökobilanzierung adaptiver Hüllen und Strukturen

2023-04-06 , Borschewski, David , Albrecht, Stefan , Bischoff, Manfred , Blandini, Lucio , Bosch, Matthias , Dazer, Martin , Efinger, Dshamil Daniel , Eisenbarth, Christina , Haase, Walter , Kreimeyer, Matthias , Leistner, Philip , Nitzlader, Markus , Roth, Daniel , Sawodny, Oliver , Adel, Friederike van den , Voigt, Michael , Simon Weber

Die Bilanzierung von Umweltwirkungen spielt eine entscheidende Rolle bei der Entwicklung nachhaltiger und umweltfreundlicher Technologien und Konzepte. Dies gilt auch in der Entwicklung von Gebäuden mit adaptiven Hüllen und Strukturen und stellt darüber hinaus weitreichende Anforderungen an alle beteiligten Disziplinen. Die vollständige Integration der Ökobilanzierung in den Planungs- und Auslegungsprozess ermöglicht, Umweltwirkungen als Optimierungsgrößen in den komplexen, dynamischen Berechnungswerkzeugen einzusetzen. Die bisherigen Ergebnisse des SFB 1244 bescheinigen adaptiven Tragwerken und Fassaden großes Potenzial zur Einsparung von Ressourcen und Umweltwirkungen. Die ganzheitliche Betrachtungsweise, sowohl in Bezug auf den Lebenszyklus als auch auf die interdisziplinären Wechselwirkungen, stellt sicher, dass die relevanten Effekte und Einflüsse in der Bilanzierung berücksichtigt werden. Das stellt die Methode der Ökobilanzierung selbst jedoch vor neue Herausforderungen im Umgang mit einer Vielzahl an Varianten und den umfangreichen Wechselwirkungen zwischen Auslegung und Einflüssen auf Parameter in der Nutzungsphase, wie z. B. den Energieverbrauch oder die Lebensdauer.

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Grill and chill: A comprehensive analysis of the environmental impacts of private household barbecuing in germany

2024-01-25 , Geng, Shaoran , Dorling, Kevin Christopher , Prenzel, Tobias Manuel , Albrecht, Stefan

Rising environmental consciousness has prompted increased scrutiny of the environmental impact of everyday activities, such as barbecuing - a popular summertime activity in Germany. This study aimed to explore the environmental impacts of three grilling techniques, charcoal (including reusable types such as swivel, round, and kettle grills, as well as disposable charcoal grills), gas, and electric grills, utilizing a life cycle assessment (LCA) approach including the manufacturing of grills, consumption of energy sources and grilling ingredients, as well as the end-of-life of the grills. Five impact categories were considered: global warming potential (GWP), acidification potential (AP), eutrophication potential (EP), abiotic depletion potential fossil (ADP), and land use (LU) according to the CML2016 and ReCiPe 2016 methodology. This study found that a barbeque event for four people results in GWP, AP, EP, ADP, and LU values ranging from 18 to 20 kg CO2-eq., 174 to 179 g SO2-eq., 166 to 167 g PO4-eq., 102 to 138 MJ, and 36 to 38 m2 annual crop-eq., respectively, across different types of grills. Furthermore, the ingredients proved to be the most significant contributor, surpassing 70% in all impact categories. Among the three types of grills, the electric grill emerged as the most environmentally friendly, while the disposable grill had the greatest environmental impact across the majority of categories. Lastly, the environmental impacts of varying consumer behaviors were evaluated to potentially assist consumers in adopting more sustainable grilling practices.

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Sustainable Pultruded Sandwich Profiles with Mycelium Core

2023-07-28 , Früchtl, Marion , Senz, Andreas , Sydow, Steffen , Frank, Jonas Benjamin , Hohmann, Andrea , Albrecht, Stefan , Fischer, Matthias , Holland, Maximilian , Wilhelm, Frederik , Christ, Henrik-Alexander

This research focuses on exploring the potential of mycelium as a sustainable alternative to wood or solid foam in pultruded glass fiber-reinforced plastic (GFRP) sandwich profiles. The study evaluates the performance and the environmental sustainability potential of this composite by mechanical tests and life cycle assessment (LCA). Analysis and comparison of pultruded sandwich profiles with mycelium, polyurethane (PUR) foam and chipboard demonstrate that mycelium is competitive in terms of its performance and environmental impact. The LCA indicates that 88% of greenhouse gas emissions are attributed to mycelium production, with the heat pressing (laboratory scale) being the main culprit. When pultruded profiles with mycelium cores of densities 350 and 550 kg/m 3 are produced using an oil-heated lab press, a global warming potential (GWP) of 5.74 and 9.10 kg CO 2-eq. per functional unit was calculated, respectively. When using an electrically heated press, the GWP decreases to 1.50 and 1.78 kg CO 2-eq. Compared to PUR foam, a reduction of 23% in GWP is possible. In order to leverage this potential, the material performance and the reproducibility of the properties must be further increased. Additionally, an adjustment of the manufacturing process with in situ mycelium deactivation during pultrusion could further reduce the energy consumption.

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Why are adaptive facades not widely used in practice? Identifying ecological and economical benefits with life cycle assessment

2023-03-15 , Borschewski, David , Voigt, Michael P. , Albrecht, Stefan , Roth, Daniel , Kreimeyer, Matthias , Leistner, Philip

The challenges concerning climate change require innovative approaches. Adaptive façades (AF) represent a promising approach, as making the façade adaptable brings several benefits such as less energy usage or increased comfort. Nevertheless, they are not widely used in practice, since the known advantages/motivators appeal in particular to stakeholders who have little involvement in the decision-making of the design process and entail compromises to stakeholders who do. In this article it is shown that besides the known advantages and compromises of AF, there are further motivators for stakeholders with high decision-making power. In a case study, a building with typical centralized ventilation is compared with a building where an AF with an integrated ventilation system was installed to substitute the centralized ventilation system. This results in a lower building height and corresponding weight of the construction, as the central duct system can be eliminated. 3 m of building height and up to 340 tons of material can be saved, which results in avoided impact on climate change of 110 tons CO2-eqviv. (-7%). During utilization, 615 tons of CO2-eqviv. Can be avoided. The lifecycle costs can be reduced by 485,000 € while the rentable floor space can be increased by 4%.

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