Search Results (3)

This work investigates the potential of a sorption-based thermal energy storage (TES) system for enhancing the integration of renewable energy and waste heat recovery in key sectors—industry, transport, and buildings. Sorption-based TES systems, which utilize reversible sorbent–sorbate reactions to store and release thermal energy, offer long-term storage capabilities with minimal losses. In particular, the aim of the study is to evaluate the efficiency of an adsorption TES system for various working pairs under different operating conditions, by means of a thermodynamic model (supported by experimental data). Key findings demonstrate that water-based solutions (e.g., zeolite and silica gel composites) perform well for residential and transport applications, while methanol-based solutions, such as LiCl-silica/methanol, maintain higher efficiency in industrial contexts. Short-term storage shows higher energy efficiencies compared to long-term applications, and the choice of working pairs significantly influences performance. Industrial applications face unique challenges due to extreme operating conditions, limiting the viable solutions to water-based working pairs. This research highlights the capability of sorption-based TES systems to reduce greenhouse gas emissions, improve energy efficiency, and facilitate a transition to sustainable energy practices. The findings contribute to developing cost-effective and reliable solutions for energy storage and renewable integration in various applications. Full article

In this study, the development and comparative characterization of different composite sorbents for thermal energy storage applications is reported. Two different applications were targeted, namely, low-temperature space heating (SH) and domestic hot water (DHW) provision. From a literature analysis, the most promising hygroscopic salts were selected for these conditions, being LiCl for SH and LiBr for DHW. Furthermore, two mesoporous silica gel matrixes and a macroporous vermiculite were acquired to prepare the composites. A complete characterization was performed by investigating the porous structure of the composites before and after impregnation, through N₂ physisorption, as well as checking the phase composition of the composites at different temperatures through X-ray powder diffraction (XRD) analysis. Furthermore, sorption equilibrium curves were measured in water vapor atmosphere to evaluate the adsorption capacity of the samples and a detailed calorimetric analysis was carried out to evaluate the reaction evolution under real operating conditions as well as the sorption heat of each sample. The results demonstrated a slower reaction kinetic in the vermiculite-based composites, due to the larger size of salt grains embedded in the pores, while promising volumetric storage densities of 0.7 GJ/m³ and 0.4 GJ/m³ in silica gel-based composites were achieved for SH and DHW applications, respectively. Full article

Due to global climate change and fossil fuel depletion, the rational use of thermal energy has attracted great research interest. Large differences between indoor and outdoor temperatures in cold regions results in huge amounts of heat waste and drop in indoor humidity. Ventireg, an adsorption method, has been often recommended for heat and humidity regeneration in cold countries. In this research work, VentireC, an advanced method employing two thermally coupled adsorbent beds is discussed. It allows the heat released during adsorption of moisture in one adsorber to be transferred to another adsorber to facilitate water desorption. The VentireC approach is comprehensively analysed and described in this paper. A composite adsorbent based on LiCl in silica gel pores, which can exchange up to 0.5 g-H₂O/g-sorbent, is selected for VentireC processes under cold Western Siberia conditions. Mathematical simulation of humidity recuperation, employing the selected sorbent with and without thermal coupling, demonstrates the advantages of the VentireC process. Full article