Development of a Combined Hot Water and Sorption Store for Solar Thermal Systems

Abstract

The motivation for the development of a combined hot water and sorption store is to complement the advantages and to reduce the disadvantages of the two particular storage technologies. Hot water stores offer high heat supply rates but are particularly suitable for short term storage due to heat losses whereas for a sorption store the power drain is low but it shows the advantage of a high storage density and long-term heat storage almost without losses. The combined hot water and sorption store has been developed using the example of a solar thermal system for domestic hot water preparation. The store consists of a radial stream adsorber integrated in a hot water store. Adsorption and desorption experiments in laboratory have been conducted with a prototype store in full-scale. A numerical model of the combined store has been developed and annual simulations of a solar thermal system including a combined hot water and sorption store have been conducted. The thermal performance has been compared to those of reference hot water stores. The results of the experimental and numerical investigations will be presented in this paper and the benefit of a combined hot water and sorption store applied for solar thermal systems will be discussed.