Magnetite Versus Quartzite: Potential Candidates for Thermocline Energy Storage

The objective of this work is to investigate magnetite storage performances using thermocline packed-bed single tank concept and confront it with the quartzite commonly used as TESM in this area. To achieve this purpose dual phase model for thermal energy storage (TES) is developed for describing heat and masse transfer inside the porous packed-bed contained in the storage tank. After validation, the developed model is used to simulate the thermal behavior discharging process and then to evaluate system performances by calculating discharge efficiency and storage efficiency for two TESMs: magnetite and quartzite coupled with Colza oil as a heat transfer fluid (HTF). This paper presents and discusses results of discharge efficiency and storage efficiency obtained for both TESM and highlights the impact of TESM choice on TES efficiency.