Experimental research on integrated heating of solar air and solar water with phase change energy storage

Abstract

Solar heating is universally recognized to be a useful method in sustainable buildings while phase change energy storage is capable of optimizing solar heating system. The space for heat storage tank is saved and heat loss at night is effectively avoided if it is used. This paper studied the feasibility of integrated heating of solar air and solar water with phase change energy storage in a room facing south. A solar air collector was integrated in the south wall and the whole-glass vacuum solar water collector system was installed on the building roof. The PCM floor including capillary plaits and macro-packaged PCM layer was used as the heating end and also as the heat storage tank for heating the room at night when solar system stopped working. Temperature, heat flux detection apparatus and flow meters were used in the experimental test. The result shows that the combination of solar air heating and solar water floor heating with phase change energy storage is feasible to create acceptable indoor thermal environment. The temperature of the room remains above 16 C for a whole day and the latent heat capacity of the PCM floor is well utilized. Thermal efficiency of solar air heating is 19.6% lower than solar water heating system in which whole-glass vacuum tube collector were used, however its function of auxiliary heating alleviate the burden of floor heating by solar heated water.