• Energy Research
• 12. Responsible consumption close
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• Technical University of Munich close

Background. Laws that enable a circular economy (CE) are being enacted globally, but reliable standardized and digitized CE data about products is scarce, and many CE platforms have differing exclusive formats. In response to these challenges, the Ministry of The Economy of Luxembourg launched the Circularity Dataset Standardization Initiative to develop a globalized open-source industry standard to allow the exchange of standardized data throughout the supply cycle, based on these objectives: (a) Provide basic product circularity data about products. (b) Improve circularity data sharing efficiency. (c) Encourage improved product circularity performance. A policy objective was to have the International Organization for Standardization (ISO) voted to create a working group. Methods. A state-of-play analysis was performed concurrently with consultations with industry, auditors, data experts, and data aggregation platforms. Results. Problem statements were generated. Based on those, a solution called Product Circularity Data Sheet (PCDS) was formulated. A proof of concept (POC) template and guidance were developed and piloted with manufacturers and platforms, thus fulfilling objective (a). For objective (b), IT ecosystem requirements were developed, and aspects are being piloted in third party aggregation platforms. Objective (c) awaits implementation of the IT ecosystem. The policy objective related to the ISO was met. Conclusions and future research. In order to fully test the PCDS, it is necessary to: conduct more pilots, define governance, and establish auditing and authentication procedures.

The concept of the Misselhorn cycle is introduced as a power cycle that aims for efficient waste heat recovery of temperature sources below 100 °C. The basic idea shows advantages over a standard Organic Rankine Cycle (ORC) in overall efficiency and utilization of the heat source. The main characteristic of this cycle is the use of at least three parallel batch evaporators instead of continuous heat exchangers. The operational phases of the evaporators are shifted so that there is always one vaporizer in discharge mode. A transient MATLAB® model (The MathWorks: Natick, MA, USA) is used to simulate the achievable performance of the Misselhorn cycle. The calculations of the thermodynamic states of the system are based on the heat flux, the equations for energy conservation and the equations of state found in the NIST Standard Reference Database 23 (Reference Fluid Thermodynamic and Transport Properties - REFPROP, National Institute of Standards and Technology: Gaithersburg, MD, USA). In the isochoric batch evaporation, the pressure and the corresponding boiling temperature rise over time. With a gradually increasing boiling temperature, no pinch point limitation occurs. Furthermore, the heat source medium is passed through the evaporators in serial order to obtain a quasi-counter flow setup. It could be shown that these features offer the possibility to gain both high thermal efficiencies and an enhanced utilization of the heat source at the same time. A basic model with a fixed estimated heat transfer coefficient promises a possible system exergy efficiency of 44.4%, which is an increase of over 60% compared to a basic ORC with a system exergy efficiency of only 26.8%.

Adaptive Building Technologies have opened up a growing field of architectural research aimed at improving the overall building performance, ensuring comfort while reducing operational energy consumption. Focusing on flexibility over short timeframes, these new technologies are however rarely designed within the broader frame of sustainability over their entire lifecycle. How sustainable these zero energy technologies really are is yet to be established. The purpose of the research is to develop a flexible easy-to-use Life Cycle Assessment (LCA) tool to support creative innovation and sustainable design choices in the early concept and design stages of Adaptive Building Technologies. This paper reports on the results of the first step of the research, providing a mapping in terms of structure and contents of the parameters involved in the design of these technologies. Addressed from a holistic point of view, the elements of the system were defined though a qualitative approach: relevant parameters were collected through document analysis, reviewing the state-of-the-art technology through online databases as ScienceDirect, Scopus, MDPI, ResearchGate, and organized according to hierarchy and relevance in the different life cycle stages. As a result, the paper identifies (1) relevant parameters defining the design of Adaptive Building Technologies; (2) materials, processes and concepts specific to the design of these technologies, as compared to conventional building technologies; (3) issues and knowledge gaps to enable successive research phases; (4) specific actions in each life cycle stage for designers and producers to optimize the design of the technology. The mapping graphically and hierarchically organizes the elements of the system within a flexible structure to be implemented and integrated over time, as the technology evolves, to support parametric design and enable alternative design concepts to arise within a cradle-to-cradle perspective.

LiFeMnPO4 secondary agglomerates have been aged under different temperature and moisture conditions. The aged and pristine powder samples were then processed to water- and solvent-based cathodes. Structural studies by means of neutron and X-ray diffraction revealed that neither ageing nor water-based processing significantly modified the crystal structure of LiFeMnPO4 secondary agglomerates. Electrochemical characterization was carried out with full-cells. It was found that long-term cycling is similar independent of the solvent used for slurry preparation. Full-cells assembled with water-based cathodes show a better C-rate capability due to a more homogeneous distribution of cathode constituents compared to solvent-based ones. In no case was any negative effect of initial active material ageing on the electrochemical performance found. During ageing and processing, LiFeMnPO4 is effectively protected by carbon coating and water can be completely removed by drying since it is only reversibly bound. This contribution shows that LiFeMnPO4 secondary agglomerates allow simplified active material handling and have a high potential for sustainable water-based electrode manufacturing.

The currently still high fossil energy demand is forcing the glass industry to search for innovative approaches for the reduction in CO2 emissions and the integration of renewable energy sources. In this paper, a novel power-to-methane concept is presented and discussed for this purpose. A special focus is on methods for the required CO2 capture from typical flue gases in the glass industry, which have hardly been explored to date. To close this research gap, process simulation models are developed to investigate post-combustion CO2 capture by absorption processes, followed by a techno-economic evaluation. Due to reduced flue gas volume, the designed CO2 capture plant is found to be much smaller (40 m3 absorber column volume) than absorption-based CO2 separation processes for power plants (12,560 m3 absorber column volume). As there are many options for waste heat utilization in the glass industry, the waste heat required for CO2 desorption can be generated in a particularly efficient and cost-effective way. The resulting CO2 separation costs range between 41 and 42 EUR/t CO2, depending on waste heat utilization for desorption. These costs are below the values of 50–65 EUR/t CO2 for comparable industrial applications. Despite these promising economic results, there are still some technical restrictions in terms of solvent degradation due to the high oxygen content in flue gas compositions. The results of this study point towards parametric studies for approaching these issues, such as the use of secondary and tertiary amines as solvents, or the optimization of operating conditions such as stripper pressure for further cost reductions potential.

Microbial oil production from industrial waste streams and biogenic resources, such as biomass hydrolysates, is emerging as a sustainable alternative to use of fossil and vegetable oils. However, the carbon sources of these substrates are typically diluted, leading to low product concentrations and, therefore, high fermentation and downstream processing costs. In this study, high-cell-density yeast oil production with a defined medium, which imitated the sugar composition of a diluted substrate, a typical microalgal biomass hydrolysate, is carried out on a 50 L scale using a membrane bioreactor (MBR) consisting of a microfiltration unit suited for industrial application. The process was run on a semi-continuous mode to reduce operational costs. Oleaginous yeast Cutaneotrichosporon oleaginosus was used as a biocatalyst and lipid production was induced by phosphate deficiency in the medium with a C/P ratio of 3515 g g−1. In this way, high cellular lipid contents of up to 76.5% (w/w) of dry cell mass, an average lipid yield of 32% (w/w), and a lipid space–time yield (STY) of up to 8.88 g L−1 d−1 were achieved with final high cell densities of up to 116 g L−1 dry biomass. Furthermore, use of a defined medium and elemental analysis of the yeast cells and yeast oil enabled drawing an accurate carbon mass balance of the production system. Carbon conversion efficiencies—fraction of total carbon supplied in the form of sugars converted into lipids at the end of the process—of up to 61.5% were achieved from diluted substrates using the MBR with total cell retention. Considering these results, it is concluded that utilization of an MBR on a semi-continuous mode would be very reasonable for yeast oil production, enabling high productivities with diluted sugar substrates.

The dynamic bottom-up modelling of greenhouse gas (GHG) abatement measures in industry makes it possible to derive consistent transformation paths on the basis of heterogeneous, process-specific developments. The main focus is on the development of a transparent methodology for small-scale modelling and combination of individual GHG abatement measures. In this way, interactions between GHG abatement measures are taken into account when deriving industrial transformation paths. The presented three-part methodological approach comprises the preparation (1) and implementation (2) of GHG abatement measures as well as the resulting effects on the output parameters (3) in a technology mix module. In order to consider interactions in the measures implementation, year-specific overall measure matrices are created and prioritised based on the GHG abatement costs. Finally, the three-part methodology is tested in a consistent technology mix scenario. The results show that the methodology enables integrated industrial technology mix scenarios with a high level of climate ambition based on a plausible development of energy consumption and emissions. Compared to the reference scenario, the process-and energy-related emissions decrease by 90 million tCO2 (77% of the 1990 level in 2050). The developed methodology and the related technology mix scenario within the framework of the bottom-up industry model SmInd can support strategic decision-making in politics and an efficient transition to a greenhouse gas neutral industry.

Over the last decades, combating climate change has been an important concern for policy makers. As a result, many policies have been designed towards this direction. Being electricity generation the focus of climate change mitigation policies, important changes are expected in this sector over the next few years as a result of the implementation of such policies. However, electricity production also generates other impacts on the water, energy and land (WEL) nexus that must be further investigated. To shed some light to this issue, this paper presents and discusses the potential impacts on the water-energy-land nexus resulting from the decarbonisation of the Spanish electricity system impacts under two different long-term scenarios. Using a Life Cycle Assessment (LCA) approach, a set of environmental impacts relevant for the nexus have been analysed for the current and future electricity generation technologies in Spain. Additionally, through the use of an optimization energy model—Times-Spain—the evolution of the electricity technologies in Spain until 2030, under two different scenarios and targets has been assessed. Taking into consideration such scenarios, the global warming, acidification, eutrophication, ecotoxicity, water consumption, resource depletion and land use impacts have been estimated. Results show that, over time, together with the decrease of greenhouse gas emission, acidification and eutrophication tend to decrease in both scenarios. On the contrary, ecotoxicity and resource use impacts tend to increase.