Computational Investigation of an Electro-Thermal Energy Storage System Utilizing Desalination Salt As Heat Storage Medium

The feasibility of using desalination salt for sensible thermal energy storage (TES) has been demonstrated at a laboratory scale. This study leverages Computational Fluid Dynamics (CFD) simulations to enhance the performance and design of TES systems operating within a temperature range of 100°C to 400°C. Key considerations include dynamic charging and discharging behavior, the influence of axial conduction during discharge, and establishing heat rate limits to safeguard system integrity. Various TES configurations — shell-and-tube, concentric tube, and composite designs — were evaluated for thermal stability, energy transfer efficiency, and loss minimization. The integration of resistive heaters directly within the salt medium offers a streamlined charging mechanism but introduces challenges such as localized overheating and uneven heat distribution. CFD analyses were instrumental in optimizing heater placement and developing robust thermal management strategies to ensure uniform energy transfer and system reliability. The results indicate that axial conduction significantly impacts discharge performance by moderating temperature gradients and energy recovery efficiency. Among the designs, the shell-and-tube configuration demonstrated superior thermal stability, while the concentric tube excelled in heat transfer rates. Composite designs provided a balance between retention and transfer but required enhanced management near heat sources. Compared to traditional TES materials, desalination salt emerges as a cost-effective, sustainable option with high energy density, suitable for industrial applications and renewable energy integration.