Numerical analysis of a thermal energy storage tank charged with a flat type solar air collector

Abstract

As energy and sustainability issues related to climate change gain importance day by day, the significance of energy storage systems is increasing. Carnot Batteries, where energy can be stored thermally, constitute one of the most outstanding alternatives for the storage of excess electrical energy produced from renewable energy in the concept of smart cities. The energy is stored in the Carnot Batteries during the hours when the electricity demand is lower than the electricity production, the energy stored in the Carnot Batteries is converted into electricity during the hours when the electricity demand is higher than the electricity production. In this respect, Carnot Batteries can offer a good solution to the imbalance between energy demand and production, which is a crucial problem in energy use, and therefore, it is likely that they will be an indispensable part of the future and smart city systems. In this study, a simulation covering the charging and discharging processes of a Thermal Energy Storage tank, which receives its energy from flat type solar thermal collectors, was carried out in MATLAB. In the simulation, a 6 m height tank was divided into 60 cells and discretized, the solar radiation values were calculated locally and a solar path was created. At the time of charging, the Thermal Energy Storage tank received its energy from the solar collectors, depending on the determined solar path. In the simulation, the effects of variables related to the energy storage media such as sphericity, void fraction, charging time were investigated.