Impact of Design Parameters in Thermal Solar Water Storage Tank Systems: (A Review)

Experimental and numerical investigations on operation characteristics of seasonal borehole underground thermal energy storage

Effects of graphene doping on shape stabilization, thermal energy storage and thermal conductivity properties of PolyHIPE/PEG composites

Bamboo derived SiC ceramics-phase change composites for efficient, rapid, and compact solar thermal energy storage

Flexible engineering of advanced phase change materials

Fluidized beds are widely used in various industrial processes due to their excellent characteristics in drying, chemical reactors, solids separation, fluid catalytic cracking and combustion. Integrating phase change materials (PCMs) into fluidized beds offers a promising solution for thermal energy storage, effectively absorbing and storing thermal energy from periodic or alternating heat sources as latent heat. This technology holds significant potential for enhancing thermal energy storage capabilities of the fluidized beds., The thermal energy storage and charging and discharging efficiencies of MPCM in a pulsating fluidized bed comprising two concentric pipes have not been investigated yet. This study investigates a solid–gas pulsed fluidized bed consisting of two concentric pipes filled with microencapsulated phase change material (MPCM) and sand as the thermal energy storage system. Experiments are carried out to measure the thermal energy storage between the inner pipe containing sand and the MPCM-containing bed, analyzing the effects of the input velocity and pulsation frequency on the energy storage and recovery efficiencies of the MPCM-containing bed. Experiments are performed at three inlet velocity to minimum fluidization velocity (U/Umf) ratios of 1.1, 1.3, and 1.5, and three frequencies of 1.0, 2.5, and 5.0 Hz. Results indicate that the pulsating fluidized bed has higher thermal energy storage and recovery efficiencies than the continuous fluidized bed. Moreover, the thermal energy storage efficiency increases as the U/Umf and pulsation frequency increase; is maximized to 86.01% at a U/Umf of 1.5 and frequency of 5 Hz. In addition, higher frequencies accelerate the charging process, and the bed reaches the stabilized temperature in a shorter time. It is found that the efficiency of thermal energy recovery increases as the frequency increases and the U/Umf reduces. The maximum efficiency of thermal energy recovery is equal to 94.02% at a U/Umf of 1.1 and a frequency of 5 Hz.

A very challenging issue about solar thermal power generation is the use of a high temperature heat transfer fluid (water, oils, or molten salts) for heat transfer and thermal storage material, which may freeze at night or cold weather. When choosing air as the heat transfer fluid, the problem of freezing is eliminated. In order to increase the performance of thermal storage system which uses air as the heat transfer fluid passing through a packed bed (by ceramic spheres of Al2O3), multiple small-diameter tanks are considered to replace a single large-diameter tank with the same packed-bed volume and airflow rate in this paper. Analysis about the thermal storage performance in a short big tank and in cascade thin tanks has been made for comparison. A long passage of airflow and faster flow speed of air in the cascade thin tanks has been found significantly beneficial to thermal storage. Results about the increased thermal storage performance and increased pressure loss will be presented. Longer passage of airflow made it possible to have a longer time of high temperature of outflow air during discharging period. And faster speed of the fluid enhanced the heat transfer between air and thermal storage material. The total effective energy and thermal storage efficiency of cascade thin-tank thermal energy storage (TES) are higher. The thermal storage efficiency in the two types of thermal storage arrangement was compared for optimal design. The obtained results are of great significance to the development of using air as heat transfer fluid and rocks or ceramic spheres as the thermal storage material for thermal storage system in concentrated solar thermal power plants.

The influence of reinjection and hydrogeological parameters on thermal energy storage in brine aquifer

An allocative method of hybrid electrical and thermal energy storage capacity for load shifting based on seasonal difference in district energy planning

Solar thermal energy and CO2 storage in saline aquifers for renewable energy space heating

Advanced 3D-printed phase change materials

Epoxy composites based on phase change microcapsules with high thermal conductivity and storage efficiency by dispersing with cellulose nanofibrils

Eutectic phase change composites with MXene nanoparticles for enhanced photothermal absorption and conversion capacity

Cellulose nanofibrous/MXene aerogel encapsulated phase change composites with excellent thermal energy conversion and storage capacity

Thermal energy storage technology plays a crucial role in the thermal management system. Clay based organic phase change material has considerable advantages in the application of thermal energy storage due to low cost and high energy storage capacity. However, the low thermal conductivity of clay, especially poor interfacial thermal transfer, limits its thermal energy storage efficiency. Herein, stearic acid/reduced graphene oxide modified montmorillonite composites (SA/RGO‐MMT) were prepared by the vacuum impregnation of stearic acid into graphene modified montmorillonite matrix, which was obtained via the in situ reduction of graphene oxide on the surface of montmorillonite. Stearic acid is assembled in the porous structures of RGO‐MMT with the physical interactions. SA/RGO‐MMT possesses high melting enthalpy of 159 J/g, low extent of supercooling of 1.4 °C and excellent thermal reliability after 100 thermal cycling. Energy storage and release rates of SA/RGO‐MMT were significantly improved due to the enhanced interfacial thermal transfer by graphene. Therefore, SA/RGO‐MMT is a promising form‐stable phase change material for applications in solar heat storage fields. The strategy in this study highlights the importance of enhancing interfacial thermal transfer for the efficient thermal energy storage materials.

n-Eicosane-Fe3O4@SiO2@Cu microcapsule phase change material and its improved thermal conductivity and heat transfer performance