An experimental validation for a computational fluid dynamics (CFD) model for tubes coiled in a phase change thermal energy storage system has been conducted. Using the validated CFD model, three CFD models have been developed. The first model was developed having pins embedded on a tube with heat transfer fluid (HTF) flowing in it, with PCM surrounding the tube. Different configurations of pins on the tube have been analysed. The second model developed is similar to the first model; however, fins were embedded instead of pins. Different configurations of fins on the tube were also investigated. The last model developed was a plain copper tube surrounded by PCM with HTF flowing in it. This model was used as a benchmark for comparison for the first two models. The models were analysed for the freezing process. From this study, it was concluded that fins on the tube is better than pins on the tube. The paper gives details of the CFD models and presents the results obtained from simulations carried out using these models.