Thermal loads inside buildings with phase change materials: Experimental results

Nowadays, European policies are promoting low energy buildings because of the high amount of energy consumption of the building sector. Phase change materials (PCM) have been studied in building implementation as a passive system to reduce the energy demand. Based in the experience obtained in the experimental set-up of Puigverd de Lleida (Spain), this paper pretends to analyze experimentally the PCM performance in a scenario with internal thermal gains. The experiments were done in three different cubicles with the same internal dimensions. The selection of the constructive systems used in these three cubicles allows the authors to evaluate the impact of using PCM in a typical Mediterranean building. A domestic heat pump for summer and an electric radiator for winter were installed to control the internal temperature of the cubicles. The results of summer period experiments show that the PCM cubicle stored the heat produced by the internal loads limiting the heat dissipation to the outer environment. Therefore, the energy consumed by the HVAC system of the PCM cubicle during the cooling period is higher than that of the other cubicles that dissipated the thermal loads according to the thermal resistance of their envelopes. Therefore, the PCM selection should take into account not only the comfort temperature but also the activity and functionality of the building.