This paper focuses on the assessment of a heat and mass exchanger dedicated to an absorption/desorption seasonal thermal energy storage system. The closed sorption heat storage based on water vapour absorption in aqueous sodium hydroxide (NaOH-H2O) solution theoretically achieves a significantly higher volumetric energy density compared to conventional hot water storage systems. To this purpose, a prototype designed for a power output of 10 kW was built and operated in both absorption and desorption mode under steady state boundary conditions.

SPF Institute for Solar Technology