Thermal Energy Storage (TES) is a significant topic of interest as it offers a low-cost method to store and deliver energy when needed. There are several forms of thermal energy storage ranging from sensible, latent, and thermochemical. In this paper, the various forms of thermal energy storage have been reviewed, and the mathematical modelling of the charging process for phase change thermal energy storage system has been formulated for use in a typical fast-food outfit where significant amounts of heat energy are readily available for capture during the day and re-use at night. The behavior of the Phase Change Material (PCM) during melting in a cylindrical encapsulation under fixed boundary conditions: location of the solid-liquid interface across the phase change material, transient temperature distribution of the liquid phase and latent heat absorbed are also analyzed.