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ABSTRACTWe present an analysis of the performance data of a monitored PV system onboard a light commercial electric vehicle during parking and driving conditions in the Hannover region of Germany. The PV system's nominal power is 2180 WP with flat silicon modules on the vehicle's roof, rear, left, and right sides and other electronic components needed to charge the vehicle's high‐voltage (HV) battery. The analysis indicated that after 488.92 h of operation, the modules mounted on the vehicle roof produced 133.32 kWh of electricity during parking at the best possible orientation compared to 15.4, 30.67, and 22.99 kWh for the modules mounted on the rear, left, and right sides, respectively. During the trips, after 31.99 h of operation, 6.12, 0.68, 1.08, and 1.86 kWh of electricity were produced by the modules on the roof, rear, left, and right sides, respectively. The overall system efficiency was in the 60%–65% range. The aggregated usable electricity reaching the HV battery after multiple conversion stages generated by the system at the two parking locations was 129.39 kWh. PV electricity generated at the two parking locations enabled a range extension of approximately 530 km, which is 30% of the total distance driven during the measurement period between April and July 2021.

ABSTRACTWe present an analysis of the performance data of a monitored PV system onboard a light commercial electric vehicle during parking and driving conditions in the Hannover region of Germany. The PV system's nominal power is 2180 WP with flat silicon modules on the vehicle's roof, rear, left, and right sides and other electronic components needed to charge the vehicle's high‐voltage (HV) battery. The analysis indicated that after 488.92 h of operation, the modules mounted on the vehicle roof produced 133.32 kWh of electricity during parking at the best possible orientation compared to 15.4, 30.67, and 22.99 kWh for the modules mounted on the rear, left, and right sides, respectively. During the trips, after 31.99 h of operation, 6.12, 0.68, 1.08, and 1.86 kWh of electricity were produced by the modules on the roof, rear, left, and right sides, respectively. The overall system efficiency was in the 60%–65% range. The aggregated usable electricity reaching the HV battery after multiple conversion stages generated by the system at the two parking locations was 129.39 kWh. PV electricity generated at the two parking locations enabled a range extension of approximately 530 km, which is 30% of the total distance driven during the measurement period between April and July 2021.

With the rising demand for fuel and the societal shift toward sustainable resources, lignin emerges as a prime feedstock. Lignin is mainly composed of aromatic compounds linked within a complex matrix and holds significant potential as a source of renewable aromatics. Technical lignin, the most abundant form of lignin, is often degraded due to harsh biomass pretreatment processes. Cu20MgAlO x porous mixed oxide (CuPMO) is an efficient catalyst to help solvolyze technical lignin. Here, we demonstrate the promotion of such mixed oxides with Mn toward improving both the yield of monomers and solubilized lignin oil. The promotion was highest at a Cu/Mn ratio of unity, resulting in a 2-fold increase in monomer extraction compared to the benchmark CuPMO. The Mn-doped catalyst produced more saturated products. Simultaneously, solvent consumption decreased with increasing Mn content. X-ray diffraction (XRD) and X-ray photoelectron (XPS) analyses revealed the formation of a Cu-Mn spinel oxide. The proximity of Cu and Mn in this precursor facilitated the reduction of Mn through hydrogen spillover from Cu0 formed during catalyst reduction during heating in the reaction mixture. The observed increase in saturated products, coupled with enhanced lignin solvolysis, highlights the superior hydrogenation capability of the CuMnMgAlO x catalyst for the solvolysis of technical lignin.

With the rising demand for fuel and the societal shift toward sustainable resources, lignin emerges as a prime feedstock. Lignin is mainly composed of aromatic compounds linked within a complex matrix and holds significant potential as a source of renewable aromatics. Technical lignin, the most abundant form of lignin, is often degraded due to harsh biomass pretreatment processes. Cu20MgAlO x porous mixed oxide (CuPMO) is an efficient catalyst to help solvolyze technical lignin. Here, we demonstrate the promotion of such mixed oxides with Mn toward improving both the yield of monomers and solubilized lignin oil. The promotion was highest at a Cu/Mn ratio of unity, resulting in a 2-fold increase in monomer extraction compared to the benchmark CuPMO. The Mn-doped catalyst produced more saturated products. Simultaneously, solvent consumption decreased with increasing Mn content. X-ray diffraction (XRD) and X-ray photoelectron (XPS) analyses revealed the formation of a Cu-Mn spinel oxide. The proximity of Cu and Mn in this precursor facilitated the reduction of Mn through hydrogen spillover from Cu0 formed during catalyst reduction during heating in the reaction mixture. The observed increase in saturated products, coupled with enhanced lignin solvolysis, highlights the superior hydrogenation capability of the CuMnMgAlO x catalyst for the solvolysis of technical lignin.

To solve societal, sustainability-related issues, higher education requires new and innovative didactical concepts in learning. We introduce the concept of transdisciplinary-CBL (T-CBL) to explicate the role of diverse disciplinary and extra-academic actors in learning processes where students work in teams to co-create innovative solutions to societal challenges. To increase our understanding of how students learn from different actors in T-CBL, we used a survey, semi-structured interviews and sociograms to elaborate the nature of interactions with and the value students ascribed to these actors. The results show that students learn from a wide variety of actors in T-CBL. Extra-academic actors help by contributing expertise and informing solution pathways, whereas friends and family provide emotional support. T-CBL results in specific learning gains including perspective-taking. The results offer a picture of T-CBL as social learning in which students interact with networks of actors from which they learn ‘on-demand’.

To solve societal, sustainability-related issues, higher education requires new and innovative didactical concepts in learning. We introduce the concept of transdisciplinary-CBL (T-CBL) to explicate the role of diverse disciplinary and extra-academic actors in learning processes where students work in teams to co-create innovative solutions to societal challenges. To increase our understanding of how students learn from different actors in T-CBL, we used a survey, semi-structured interviews and sociograms to elaborate the nature of interactions with and the value students ascribed to these actors. The results show that students learn from a wide variety of actors in T-CBL. Extra-academic actors help by contributing expertise and informing solution pathways, whereas friends and family provide emotional support. T-CBL results in specific learning gains including perspective-taking. The results offer a picture of T-CBL as social learning in which students interact with networks of actors from which they learn ‘on-demand’.

Polar codes concatenated with a cyclic redundancy check (CRC) code have been selected in the 5G standard with the successive-cancellation list (SCL) of list size L = 8 as the baseline algorithm. Despite providing great error-correction performance, a large list size increases the hardware complexity of the SCL decoder. Alternatively, flip decoding algorithms were proposed to improve the error-correction performance with a low-complexity hardware implementation. The combination of list and flip algorithms, the successive-cancellation list flip (SCLF) and dynamic SCLF (DSCLF) algorithms, provides error-correction performance close to SCL-32 with a list size L = 2 and Tmax = 300 maximum additional trials. However, these decoders have a variable execution time, a characteristic that poses a challenge to some practical applications. In this work, we propose a restart mechanism for list–flip algorithms that allows us to skip parts of the decoding computations without affecting the error-correction performance. We show that the restart location cannot realistically be allowed to occur at any location in a codeword as it would lead to an unreasonable memory overhead under DSCLF. Hence, we propose a mechanism where the possible restart locations are limited to a set and propose various construction methods for that set. The construction methods are compared, and the tradeoffs are discussed. For a polar code of length N = 1024 and rate ¼, under DSCLF decoding with a list size L = 2 and a maximum number of trials Tmax = 300, our proposed approach is shown to reduce the average execution time by 41.7% with four restart locations at the cost of approximately 1.5% in memory overhead.

Polar codes concatenated with a cyclic redundancy check (CRC) code have been selected in the 5G standard with the successive-cancellation list (SCL) of list size L = 8 as the baseline algorithm. Despite providing great error-correction performance, a large list size increases the hardware complexity of the SCL decoder. Alternatively, flip decoding algorithms were proposed to improve the error-correction performance with a low-complexity hardware implementation. The combination of list and flip algorithms, the successive-cancellation list flip (SCLF) and dynamic SCLF (DSCLF) algorithms, provides error-correction performance close to SCL-32 with a list size L = 2 and Tmax = 300 maximum additional trials. However, these decoders have a variable execution time, a characteristic that poses a challenge to some practical applications. In this work, we propose a restart mechanism for list–flip algorithms that allows us to skip parts of the decoding computations without affecting the error-correction performance. We show that the restart location cannot realistically be allowed to occur at any location in a codeword as it would lead to an unreasonable memory overhead under DSCLF. Hence, we propose a mechanism where the possible restart locations are limited to a set and propose various construction methods for that set. The construction methods are compared, and the tradeoffs are discussed. For a polar code of length N = 1024 and rate ¼, under DSCLF decoding with a list size L = 2 and a maximum number of trials Tmax = 300, our proposed approach is shown to reduce the average execution time by 41.7% with four restart locations at the cost of approximately 1.5% in memory overhead.

This report presents the results of the quantification of potential operational energy savings achieved by the ZERAF adaptive opaque façade technology through building-level energy simulations. This study evaluates the technology's impact compared to established benchmark façades across diverse European conditions, providing preliminary, non-validated results. The assessment employed dynamic building energy simulations using three representative building archetypes (Single-Family House - SFH, Multi-Family House - MFH, and Office) derived from the IWG5 project. These models were simulated across six distinct European climates (Stockholm, Berlin, Bolzano, Milan, Athens, Madrid). ZERAF's performance was systematically compared against three passive envelope standards (Typical, Compliant, Gold) and two advanced passive façade concepts (Ventilated Façade variants and the INFINITE façade). Key metrics analyzed include annual heating, cooling, and total energy demand intensities (kWh/m²·year), supplemented by detailed hourly analysis of thermal performance during typical summer and winter weeks. The simulation findings indicate that the ZERAF system consistently achieves the lowest total annual energy demand intensity across all climates for the SFH and MFH typologies, significantly outperforming even the highly insulated passive Gold standard. Reductions relative to the Typical baseline ranged from 82% to 93%, while savings compared to the Gold standard were particularly substantial in warmer climates (up to 66% further reduction in Athens) and still notable in colder climates (up to 39% further reduction in Bolzano). Crucially, unlike passive ventilated façades, which reduce cooling loads at the expense of increased heating demand, ZERAF demonstrated the ability to reduce both heating and cooling demands compared to the Gold standard, highlighting the benefit of active, adaptive control. In the Office archetype, where ZERAF was applied to a limited façade area, performance improvements over Gold were less pronounced but still consistently observed across all climates. Detailed weekly analyses confirmed the synergistic operation of ZERAF's components. In summer, the combined action of KC (shading/ventilation) and ActIns (nighttime heat dissipation) led to lower indoor temperatures, reduced cooling peaks, and significantly lower cooling energy consumption compared to baseline conditions or the individual components operating alone. In winter, ZERAF effectively reduced heat loss through closed-loop active insulation (ActIns) and passive solar gain utilization (enabled by KC and ActIns), resulting in reduced heating demand and more stable indoor temperatures. While these results strongly suggest significant energy-saving potential, they are preliminary and based on simulations. Key future work includes the experimental calibration of the specific KC and ActIns component models against laboratory data to increase confidence in their simulated behavior. Furthermore, optimization of the integrated control strategy is necessary, as analysis revealed specific conditions where performance could potentially be improved. Broadening the analysis to include realistic HVAC system interactions, optimizing ZERAF system control strategy, varying building thermal mass, diverse occupant behavior profiles, and performance under future climate scenarios will provide a more comprehensive assessment. In conclusion, this simulation study provides compelling, albeit non-validated, evidence that the ZERAF active façade technology offers substantial potential for reducing building operational energy consumption across Europe, significantly surpassing the performance of both standard and advanced passive envelope solutions through its adaptive capabilities.

This report presents the results of the quantification of potential operational energy savings achieved by the ZERAF adaptive opaque façade technology through building-level energy simulations. This study evaluates the technology's impact compared to established benchmark façades across diverse European conditions, providing preliminary, non-validated results. The assessment employed dynamic building energy simulations using three representative building archetypes (Single-Family House - SFH, Multi-Family House - MFH, and Office) derived from the IWG5 project. These models were simulated across six distinct European climates (Stockholm, Berlin, Bolzano, Milan, Athens, Madrid). ZERAF's performance was systematically compared against three passive envelope standards (Typical, Compliant, Gold) and two advanced passive façade concepts (Ventilated Façade variants and the INFINITE façade). Key metrics analyzed include annual heating, cooling, and total energy demand intensities (kWh/m²·year), supplemented by detailed hourly analysis of thermal performance during typical summer and winter weeks. The simulation findings indicate that the ZERAF system consistently achieves the lowest total annual energy demand intensity across all climates for the SFH and MFH typologies, significantly outperforming even the highly insulated passive Gold standard. Reductions relative to the Typical baseline ranged from 82% to 93%, while savings compared to the Gold standard were particularly substantial in warmer climates (up to 66% further reduction in Athens) and still notable in colder climates (up to 39% further reduction in Bolzano). Crucially, unlike passive ventilated façades, which reduce cooling loads at the expense of increased heating demand, ZERAF demonstrated the ability to reduce both heating and cooling demands compared to the Gold standard, highlighting the benefit of active, adaptive control. In the Office archetype, where ZERAF was applied to a limited façade area, performance improvements over Gold were less pronounced but still consistently observed across all climates. Detailed weekly analyses confirmed the synergistic operation of ZERAF's components. In summer, the combined action of KC (shading/ventilation) and ActIns (nighttime heat dissipation) led to lower indoor temperatures, reduced cooling peaks, and significantly lower cooling energy consumption compared to baseline conditions or the individual components operating alone. In winter, ZERAF effectively reduced heat loss through closed-loop active insulation (ActIns) and passive solar gain utilization (enabled by KC and ActIns), resulting in reduced heating demand and more stable indoor temperatures. While these results strongly suggest significant energy-saving potential, they are preliminary and based on simulations. Key future work includes the experimental calibration of the specific KC and ActIns component models against laboratory data to increase confidence in their simulated behavior. Furthermore, optimization of the integrated control strategy is necessary, as analysis revealed specific conditions where performance could potentially be improved. Broadening the analysis to include realistic HVAC system interactions, optimizing ZERAF system control strategy, varying building thermal mass, diverse occupant behavior profiles, and performance under future climate scenarios will provide a more comprehensive assessment. In conclusion, this simulation study provides compelling, albeit non-validated, evidence that the ZERAF active façade technology offers substantial potential for reducing building operational energy consumption across Europe, significantly surpassing the performance of both standard and advanced passive envelope solutions through its adaptive capabilities.