Experimental and numerical investigations of a zeolite 13X/water reactor for solar heat storage in buildings

•An open cycle heat storage using zeolite 13X/H2O is investigated.•A 1D reactor model is developed and compared to experimental results.•40kg batches generated up to 38°C of temperature lift during 8h of discharging. This paper addresses the thermal performances of a zeolite-based open sorption heat storage system to provide thermal energy for space heating needs. The study focuses on the experimentation of a significant scale prototype using zeolite 13X/H2O as the reactive pair, and on the development of a 1D mathematical model used to predict both the charging (desorption) and the discharging (adsorption) processes occurring inside the storage unit. The experimental campaigns and the numerical results lead to some promising conclusions on the thermal performances of such a storage unit. With 40kg of zeolite, a temperature lift of 38°C on average at the outlet of each zeolite’s vessel during 8h was achieved during the discharging with an airflow inlet at 20°C, 10g/kg of dry air of specific humidity and a flow rate of 180m3/h. Some discrepancies between the experimental and simulation results were observed during both the charging and discharging tests, and were explained.