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New generations of SiC power devices require to be fabricated on very thin substrates, in order to significantly reduce the series resistance of the device. The role of thinning process on the formation of backside ohmic contact has been investigated in this work. Three different mechanical grinding processes have been adopted, resulting in different amounts of defectivity and surface roughness values. An excimer UV laser has been used to form a Ni-silicide based ohmic contact on the backside of the wafers. The reacted layer has been studied by means of Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM) and X-Ray Diffraction (XRD) analyses, as a function of grinding process parameters and laser annealing conditions. The ohmic contact has been evaluated by measuring the Sheet Resistance (Rs) of silicided layers and the Vf at nominal current of Schottky Barrier Diode (SBD) devices, fabricated on 150 mm-diameter 4H-SiC wafers. A strong relationship has been found between the crystal damage, induced by thinning process, and the structural, morphological and electrical properties of silicided ohmic contact, formed by UV laser annealing, revealing that the silicide reaction is moved forward, at fixed annealing conditions, by the increasing of crystal defectivity and surface roughness of SiC.

The energy consumption for cooling takes up 50% of all the consumed final energy in Europe, which still highly depends on the utilization of fossil fuels. Thus, it is required to propose and develop new technologies for cooling driven by renewable energy. Also, thermal energy storage is an emerging technology to relocate intermittent low-grade heat source, like solar thermal energy and industrial waste heat as well as to exploit off-peak electricity, for cooling applications. This review aims to summarize the recent advances in thermally driven cooling and cold storage technologies, focusing on the formation and fabrication of adopted composites materials, including sorption materials, phase change materials, and slurries. Herein, first the classifications, selection criteria, and properties for these three types of materials is discussed. Then, the application potentials of all the materials are prospected in terms of economic analysis and sustainability.

This paper presents a comprehensive examination of the integration of heat pumps and thermal energy storage (TES) within the current energy system. Utilizing bibliometric analysis, recent research trends and gaps are identified, shedding light on the evolving landscape of this dynamic field. The study delves into the research outputs since 1969, offering insights into the global scholarly contributions shaping the discourse. Furthermore, an extensive policy analysis is conducted, focusing on seven countries with the highest research output. The interplay between research advancements and energy policies is explored, providing an understanding of the practical implications of the integration of heat pumps and TES. An understanding is tried to reach as how research and policy sector influence each other. This analysis contributes not only to the academic understanding of the subject but also informs policymakers about potential pathways for enhancing energy efficiency and sustainability in heating and cooling sector.

In the present work, adsorption performances of an innovative composite adsorber, based on SAPO-34-silicone composite macro-cellular foams, are reported. The choice of a foamed structure was assessed to improve the water vapor access towards the embedded zeolite keeping good adsorption heat pump dynamic performance. Depending on zeolite amount used as filler, zeolite/silicone foams evidenced a soft and open cell configuration (low zeolite content) or rigid and closed one (high zeolite content). Morphological analysis evidenced that the cellular structure of the foam is homogeneous and well distributed along the foam cross section. Adsorption tests showed that the adsorbent foamed samples have very effective adsorption capabilities indicating that the porous structure of the filled pure zeolite was not obstructed. SAPO-34 filler contributed actively, with an efficiency above 90%, to the adsorption performances of the composite foam. Starting from experimental equilibrium data, a simple thermodynamic analysis based on energy balances was carried out for air conditioning application. Results of the analysis demonstrated that foam technology can guarantee cooling COP up to 7% higher than that estimated for the typical adsorber solution based on loose adsorbent grains inside an aluminum finned-flat tube heat exchanger, which is very promising for practical application in adsorption heat pumps.

•Improvement of the Thermal safety of LTO batteries.•Experimental tests at high current and high environmental ambient temperature.•Taguchi optimization of passive battery thermal management systems.•Parametric simulations of PCM-based and hybrid PCM + water cooling systems.•Hybrid system identified as the most viable solution to prevent thermal runaway.

Sorption thermal energy storage systems have higher energy densities and low long-term thermal losses compared to traditional energy storage technologies, which makes them very attractive for seasonal heat storage application. Although they have a lot of potential at material level, its operation and system implementation for residential application requires further study. The performance of a seasonal sorption thermal energy storage system strongly depends on the discharging process during the cold season. The present study analysed through numerical simulations different scenarios to enhance the thermal performance of a solar-driven seasonal water-based sorption storage, which supplied space heating and domestic hot water to a single-family house in a cold climate region. All studied scenarios were analysed under optimal control policy. The results indicated that the sorption storage could increase by 9 % its energy density if conservative and constant discharging temperature set points are considered, due to fewer interruptions during the discharge. The energy density of the sorption storage driven by solar energy was highly impacted by the weather conditions, and by the type and availability of low-temperature heat source. Indeed, the energy density of the sorption storage increased by 22 % using a water tank to assist the evaporator of the sorption storage, instead of a latent storage tank. The use of a dry-heater to assist the evaporator with environmental heat was not suitable for the climate studied due to the low hours of operation. The sorption storage system composed of 20 modules of LiCl-silica gel could obtain an energy density and a COP of 139 kWh/m3and 0.39, respectively, if a constant low-temperature heat source (i.e, geothermal or waste energy) was available.

Extensive research has been conducted on utilizing phase change materials for cooling applications, making it one of the most explored techniques in this domain. This research paper presents a comprehensive performance evaluation of a latent heat thermal energy storage unit featuring three distinct macro-encapsulation designs for phase change materials. The study aims to assess the thermal performance, efficiency, and practical applicability of these macro-encapsulation designs in a storage system. The PCM macro-encapsulation designs under investigation include cylindrical and rectangular shapes, each possessing different geometry. Two different configurations have been considered in this study. One configuration contains same PCM mass in order to have similar storage capacity while the other configuration has maximum PCM mass that can be inserted inside the tank. The used phase change material is a salt hydrate with melting temperature of 17 °C. The experimental setup consists of a controlled test rig that simulates real-world conditions and enables the comparative analysis of the three designs. Key performance parameters such as the charging and discharging time, temperature profiles, heat transfer rate, and energy storage/retrieval rates are measured and analysed. The results obtained from the experimental study provide valuable insights into the thermal behaviour, energy storage capacity, and overall effectiveness of the three macro-encapsulation designs. It is important to mention that use of an encapsulation design is highly dependent on application. The findings of this study contribute to the understanding of the impact of different macro-encapsulation designs on performance of thermal energy storage units. The results serve as a basis for optimizing macro-encapsulation designs, improving the efficiency and reliability of latent heat storage systems, and promoting their wider adoption in various energy management applications.

The deployment of adsorption cycles for heating and cooling purposes is often limited by poor efficiency and high reactor volumes, both determined by the adsorber material used. The appropriate pre-selection of the solid sorbent and the system design in the early stages of design can allow quick identification of the most promising solutions. In this work, a reliable and robust methodology for adsorber material screening and pre-selection is proposed and applied to a test set of state-of-the-art candidates. The improvement achieved in the adsorption equilibrium prediction with respect to the most frequently used model is above 60%. In addition, the adsorber material selection framework based on mixed-integer linear programming was applied to over 600 hypothetical cooling and mixed cooling/heating use cases. The analysis of exergy and volume performances allowed to emphasize differences of design strategies using different system objectives (i.e. minimizing the temperature of the heat sources and choosing compact materials). We provide the proof of feasibility of a harmonic pre-design of adsorbent materials and energy system and show that it can be used to narrow down the decision variables to the most promising options. This methodology can be considered as the foundation of more extended and automated design methods for real scenarios constrained by kinetics, material integration and costs.

•Review of numerical modeling techniques and correlation for thermocline storage.•Optimal design and operating parameters range is discussed.•Selection of the most suitable model and its calibration for various applications presented.

To address the issues of poor thermal conductivity and fragmentation of metal hydride particles undergoing hydriding/dehydriding reactions, a metal hydride-based composite material was developed. The active metal phase was embedded in a silica matrix and a graphite filler was incorporated by ball milling. A set of compact pellet samples at different composition were prepared and tested. Experimental data obtained from the thermal conductivity measurements shown that using powder graphite produced a quite linear increase in the thermal conductivity of the metal hydride – silica composite. Ongoing studies include composition optimization as well as long-term testing upon cycling of such metal hydride composites to evaluate their potentiality in technological hydrogen storage applications.

Abstract: Objective: Many Health Information Activities related to nutrition and physical activity have been initiated during the past years by several institutions on the national and international level as well as by several European networks. A multitude of projects with different scopes and methodologies has arisen. This variety makes it necessary to bring the results of these activities into a coordinated framework. The report aims to give a structured overview on the availability of routine repeated or repeatable data on the health determinants nutrition and physical activity in European countries. An Inventory of Health Information Activities on physical activity and nutrition was built up, which summarises activities carried out by the European Commission, the WHO, various European Networks, as well as national examples. The Health Information Activities collected as national examples assess data for all countries belonging to the European Union up to 2006, the European Economic Area (EEA) and all Candidate countries. The Inventory considers activities which started in 1990 or later, which were still running or have been approved but not yet started. Method: The report analyses institutional structures (WHO, European Commission, European Networks) as well as examples of health information activities at the national level. A network of European public health professionals identified available national health information activities and survey data, which were summarised in a structured online database. Results: The results section presents activities in the field of health information on physical activity and nutrition of the European Commission (DG Sanco), the World Health Organisation (Europe) and various European networks. Furthermore, this section presents the analysis of the database which summarises health information activities in European countries. The database is freely accessible at the website of the Working Party. Additionally, the supplement provides a summary of Health Information Activities for each country in Country Profile Sheets. Conclusion: The report provides a general overview on Health Information Activities related to physical activity and nutrition as well as a state-of-the-art investigation about available data in European countries. The concluding section of the report aims to recommend future Health Information actions which outline open issues.

To address the issues of poor thermal conductivity and fragmentation of metal hydride particles undergoing hydriding/dehydriding reactions, a metal hydride-based composite material was developed. The active metal phase was embedded in a silica matrix and a graphite filler was incorporated by ball milling. A set of compact pellet samples at different composition were prepared and tested. Experimental data obtained from the thermal conductivity measurements shown that using powder graphite produced a quite linear increase in the thermal conductivity of the metal hydride – silica composite. Ongoing studies include composition optimization as well as long-term testing upon cycling of such metal hydride composites to evaluate their potentiality in technological hydrogen storage applications.

•Innovative model approach for adsober design•Mathematical model calibrated by means of experimental data sets for different configurations•Tool useful to evaluate achievable power and energy density under variable operating conditions

•RES penetration needs development of batteries for different applications.•Research on thermal battery management systems is assessed in a bibliometric analysis.•Most research is carried out in lithium-ion batteries.•Thermal managements systems are air cooling, liquid cooling, and phase change materials.•The biggest research gap is the lack of studies on other battery types.

•An innovative strontium bromide hexahydrated filled silicone composite foam for sorption TES applications was investigated.•The morphological and thermal features of the composite foams with different salt content were assessed.•We assessed if the composite foams could represent a promising candidate for thermal energy storage applications.