The aim of this study is to analyze a sensible heat thermal energy storage system designed for storing and later using of energy; from thermodynamic point of view, and also to obtain optimum operation conditions for various operation parameters in order to minimize the irreversibilities in the system taking into account the pressure drop effect. The operation of the investigated sensible heat thermal energy storage system is divided into two parts; storage and removal processes. Considering the first and second law of thermodynamics, each part is studied separately. The results are combined in order to get the final solution for complete system. The detailed analyses were performed from both the first and second law perspective of thermodynamics on the proposed model to store sensible energy at optimum conditions. The parametric studies were focused on the determination of optimum operational values such as dimensionless storage time, dimensionless temperature, Number of Transfer Units, the first law and second law efficiencies, the ratio of mass flow rates.