Developing a Model for Quantifying Heat Loss From a Molten Salt Thermal Storage System

Thermal energy storage (TES) systems are integral to concentrated solar power (CSP) plants. A major design consideration for TES systems is the tank's storage temperature. The tank cools over time due to heat loss through its boundaries. This paper presents a model for tracking and quantifying heat loss through the tank's floor, walls, and roof. The heat transfer mechanisms incorporated in the model are convection, conduction, and radiation. The performance of the developed model is validated against previous studies and used to understand the effect of the fluid level on tank losses. The model serves as a tool to compare different thermal energy storage (TES) system designs and gain insights into which minimises the heat loss. The paper details the modelling assumptions, methodology, and validation results. The model is intended for comparative assessment during conceptual design, enabling rapid evaluation of TES configurations where relative differences matter more than absolute precision.