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Future energy scenarios with renewables and flexibilities in distribution grids – National case study in France
No full textMedium and low voltage distribution grids are at the core of the energy transition as they are expected to host a large share of renewables and flexible resources. Their modeling within decarbonization pathways is then of great importance in providing realistic future energy scenarios. This paper investigates different scenarios at the French national scale up to 2050 while varying the electricity demand, renewables installed in both transmission and distribution grids, and the considered flexibility technologies. The methodology relies on coupling a long-term energy model (POLES) and an open-source short-term optimization framework (Backbone). POLES produces long-term decarbonization scenarios, while Backbone enables the optimization of the power system. Technical and financial impacts are studied through ten scenarios regarding produced energy, installed capacities, and investment costs. The results highlight the importance of the load demand modeling assumptions, even raising the question of the feasibility of high-demand scenarios. Also, results show that demand-side flexibility can significantly reduce the requirements in conventional storage technologies (up to 98 %). Distributed flexibilities, such as electric vehicle smart charging, are especially effective. Considering multiple types of distribution grids allows, in the end, to show that installing renewable generation at the transmission or distribution level only moderately influences global costs, with a minor advantage for centralization to limit reverse flows on transformers. The paper concludes with a comparison with other scenarios (drawn from up-to-date literature) and a discussion of the environmental footprint of these scenarios, both in terms of mineral resource consumption (raw materials) and land footprint.</p
Advances in biomaterials for medical textile applications:a review on integration strategies and sustainable innovations
No full textBiomaterials have undergone remarkable evolution over recent decades, driven by advances in molecular design, synthesis techniques, and functional optimization. These innovations have transformed biomedical applications, addressing critical global healthcare challenges. Early-career researchers have played a pivotal role in this progress through interdisciplinary approaches and novel methodologies. This review provides a systematic assessment of biomaterials in medical textile applications, covering performance characteristics, fabrication strategies, and emerging eco-friendly alternatives. It highlights recent interdisciplinary developments and innovative concepts not addressed in previous literature, offering new perspectives to guide future research in biomedical textiles. Furthermore, the review presents an in-depth analysis of biomaterial-based approaches for medical textiles, emphasizing strategies for next-generation functional polymers. Medical textiles, essential in clinical practice, demand stringent properties such as biocompatibility, mechanical strength, and functionality. Applications include wound dressings, implants, surgical sutures, and drug delivery systems. Incorporating advanced biomaterials into these textiles has improved therapeutic efficacy, patient outcomes, and sustainability. This paper evaluates the performance of various biomaterials, explores innovative fabrication and functionalization techniques, and discusses eco-friendly alternatives to overcome limitations of conventional materials. Ultimately, the review underscores the potential of biomaterial-enabled medical textiles in shaping personalized and regenerative healthcare.</p
Tuning physical performance of gelatin-cellulose nanocrystals hydrogels
No full textStimuli-responsive hydrogels are interesting, particularly in the realm of biomedicals, but often the fundamental response of their key physical properties is not simultaneously monitored. Here, we investigated the pH response on the porosity, rheological behavior, mechanical performance, and molecular diffusivity of a hydrogel system composed of two bio-based components: gelatin and rod-like cellulose nanocrystals (CNCs). By leveraging the pH-responsive nature of gelatin, we systematically examined the structural properties of these hydrogels formed under three pH conditions: below (pH 5), above (pH 11), and at the isoelectric point (pH 8) of type A gelatin. All hydrogels exhibited a distinct cellular architecture, characterized by micron-scale tubular pores with embedded mesopores. Increasing pH upon the hydrogel crosslinking promoted the formation of more porous structures with significantly enhanced mechanical performance. The effect on the Young's modulus was significant: with a 3-fold increase compared to its counterparts, the hydrogel fabricated at pH 11 exhibited the stiffest structure. This improvement in hydrogel stiffness with pH further restricted the molecular diffusivity within the hydrogels to some extent, as evidenced by Fluorescence Recovery After Photobleaching analysis using fluorescein isothiocyanate-dextran as a diffusion probe. Overall, this study presents a straightforward and effective strategy for fabricating pH-tunable hydrogels, providing valuable insights for the design of responsive biomaterials with potential applications in soft tissue engineering and drug delivery.</p
Effect of Green Fuels on Marine Engine Lubrication
No full textHydrogen and ammonia have been considered as prominent fossil-free energy source candidates. While their combustion characteristics and emission profiles are well-documented, the implications for engine lubrication systems remain underexplored. This study aims to bridge this knowledge gap by investigating the effect of gaseous green fuels, specifically hydrogen and ammonia, and their influence on lubricants and the tribological performance of the lubricants. Applying a rapid and cost-effective lab-scale ageing process, the ageing effects of gas and gas admixtures were simulated and differentiated in a controlled environment. Detailed chemical, physical, and tribological analyses provide valuable insights into the different degradation outcomes of the lubricants with different exposing gases. The results revealed degradation of lubricant performance after ageing with the gases, due to changes in the lubricant chemistry and, in some cases, viscosity at 100 °C. In all cases, lubricant ageing introduced increase in friction coefficient between steel surfaces and impairment of the lubricant load-carrying capacity. The results obtained from this work will benefit the appropriate selection of lubricant alternatives for future engines utilizing green fuels and facilitate the development of more effective and durable lubrication solutions to support the broader adoption of hydrogen and ammonia as sustainable energy sources in internal combustion engines.</p
Evaluating Net-Zero Energy Buildings and Their Grid Interaction: A Comprehensive Framework for Operational Phase and A Nordic Case Study
No full textThis paper presents a synthesized evaluation framework for assessing Net-Zero Energy Buildings (NZEBs) during their operational phase, with a specific focus on grid interaction under real market conditions. The framework integrates four established Key Performance Indicators (KPIs): Load/Generation Balance, Self-Consumption Rate, Emission Reduction Rate and Cost Reduction Rate – using high-resolution operational data, hourly grid emission factors, and spot prices. Demonstrated through a case study of a large Finnish residential NZEB equipped with a ground-source heat pump and off-site solar PV, the analysis reveals both the potential and limitations of PV-based solutions in cold climates. While the system achieved an 89% annual load/generation balance, hourly analysis showed a 31% self-consumption rate, with most PV production exported during periods of low prices and low emissions. Operational emissions and electricity costs were reduced by 56% and 41%, respectively, compared to a baseline without PV. However, sensitivity analysis indicates that economic outcomes are highly dependent on prevailing market conditions, highlighting the importance of multi-year evaluation. The framework’s parallel KPIs, when used collectively, enable stakeholders to assess trade-offs and guide practical decisions regarding demand-side management, energy storage, and operational strategies. The economic analysis focuses on market exposure, including O&M costs for PV, but excluding investment costs. The framework is flexible and can be applied to NZEBs with various configurations, supporting robust, data-driven decision-making for improved cost-effectiveness and decarbonization
Cybersecurity for 5G-Enabled IoT Ecosystems:Introduction, Challenges, and Solutions
No full text5G and Internet of Things complement each other in contributing towards the advancements of various relevant regimes like healthcare, smart cities, and industrial automation. This combination also brings cybersecurity as potential challenge due to abrupt surge in network devices and components. This chapter addresses various concerns like the significant challenges in 5G-enabled IoT systems, gauging effectiveness of existing solution and the next-generation solutions for the protection of 5G-enabled IOT in future. The study evaluates advanced solutions such as AI-based anomaly detection, privacy-preserving analytics etc. Backed by simulations and real-world case studies, the findings highlight the practical potential of these approaches to enhance IoT security and resilience. The following chapter is expected to provide the significant mentoring to the different stakeholders like young researchers, key industry personals, law administrators for creating the awareness about various steps towards designing and maintaining 5G-enabled IoT ecosystems with security as well as scalability.</p
Techno-functional and nutritional evaluation of Solein single-cell protein and its application in non-dairy yoghurt alternatives
No full textThe growing global population and climate crisis demand expanding non-animal protein options. Single-cell protein biomass, referred to as “Solein”, is produced by the hydrogen-oxidising bacterium Xanthobacter sp. SoF1 and is a promising, sustainable source of protein and dietary fibre, especially when created using renewable energy. This study investigates Solein protein powder (SPP) for its composition and techno-functional properties, comparing it to pea protein isolate (PPI). SPP had a lower fat content and higher dietary fibre, while matching the protein content of PPI. SPP met all indispensable amino acid requirements for adults over the age of three, as outlined by the FAO in 2013. A milk alternative resembling semi-skimmed cow's milk was produced from SPP and PPI. These emulsions were fermented with a commercial starter culture containing Streptococcus thermophilus. The fermentation process was monitored by tracking pH, total titratable acidity, and microbial growth. The resulting yoghurt alternative (YA) underwent textural and rheological analysis. Solein protein powder yoghurt alternative (SPP-YA) exhibited faster acidification, greater microbial growth, improved water retention, and a texture similar to dairy yoghurt. Static in vitro digestion revealed moderate protein digestibility of the non-fermented SPP emulsion (63.8–67.5%), based on total amino acids, free amino groups, and total nitrogen, with an in vitro Digestible Indispensable Amino Acid Score (DIAAS) of (51.0 ± 6.1%). Fermentation slightly reduced digestibility (57.8–59.6%) and DIAAS (48.3 ± 1.4%), with isoleucine as the limiting amino acid. This work provides the first insight into the structural and nutritional performance of hydrogen-oxidising bacterial protein in non-dairy YA.</p
A state-of-the-art review of R&D for the supercritical water-cooled reactor technology. Part II materials & chemistry
No full textThis document presents a summary of the most relevant research and development (R&D) carried out to support the development of the only generation IV water-cooled reactor endorsed by the Generation IV International Forum (GIF).The coolant of the proposed reactor operates at supercritical water conditions, allowing for an increase in thermodynamic efficiency of the plant and the production of high-grade process heat. Several collaborations have been established to support this technology under the GIF umbrella as well as through other international avenues; as a result, the development work is bolstered by a collective effort between numerous R&D institutions across Asia, Europe, and North America. The Joint European Canadian Chinese development of Small Modular Reactor Technology (ECC-SMART) collaborative project was established to encompass the design and pre-licensing requirements as well as a roadmap demonstrating the safe operation of the supercritical water small modular reactor (SCW-SMR). One of the main challenges in the material and component aspect is the selection and qualification of a fuel cladding material that can withstand supercritical water conditions (beyond 374 °C and 22.1 MPa). The aim of the materials testing work package (WP2) in the ECC-SMART project is to achieve a deep understanding of the corrosion behavior of selected candidate cladding materials. Over 750 corrosion specimens were tested including those under nominal SCW-SMR operating conditions and also at simulated accident conditions. This article summarizes the findings from the study of corrosion behavior of non-irradiated and pre-irradiated candidate materials and from the study of the effect of chemistry and changes in the chemical properties of SCW.</p
Scientific assessment for urban air mobility (UAM)
No full textThis review article is the revised and expanded version of the Scientific Assessment for UAM document that the urban air mobility (UAM) working group of the International Forum for Aviation Research (IFAR) developed at the request of the International Civil Aviation Organization (ICAO). The assessment began with a study of the industry landscape, which includes an overview of existing market studies, proposed aircraft designs and concepts, and potential paths for industry evolution. The subsequent scientific assessment, developed through cooperative efforts among international domain experts, captures 17 focus areas relevant to UAM. Each focus area presents opportunities for further research. The assessment was delivered to the ICAO in 2023. This revised and expanded version reflects the UAM domain’s status quo, incorporating the most recent developments and trends identified in 2024. Key takeaways include: the need for further study of the impact of autonomous systems on the industry; infrastructure requirements (including vertiports and weather sensing) to support the industry sector; and data requirements (covering domains such as cybersecurity, emissions, and safety) to ensure safe and scalable UAM operations.</p
Effect of Green Fuels on Marine Engine Lubrication
No full textHydrogen and ammonia have been considered as prominent fossil-free energy source candidates. While their combustion characteristics and emission profiles are well-documented, the implications for engine lubrication systems remain underexplored. This study aims to bridge this knowledge gap by investigating the effect of gaseous green fuels, specifically hydrogen and ammonia, and their influence on lubricants and the tribological performance of the lubricants. Applying a rapid and cost-effective lab-scale ageing process, the ageing effects of gas and gas admixtures were simulated and differentiated in a controlled environment. Detailed chemical, physical, and tribological analyses provide valuable insights into the different degradation outcomes of the lubricants with different exposing gases. The results revealed degradation of lubricant performance after ageing with the gases, due to changes in the lubricant chemistry and, in some cases, viscosity at 100 °C. In all cases, lubricant ageing introduced increase in friction coefficient between steel surfaces and impairment of the lubricant load-carrying capacity. The results obtained from this work will benefit the appropriate selection of lubricant alternatives for future engines utilizing green fuels and facilitate the development of more effective and durable lubrication solutions to support the broader adoption of hydrogen and ammonia as sustainable energy sources in internal combustion engines.</p