Thermal analysis of a ventilated facade with PCM for cooling applications

• A DSF with PCM is experimentally evaluated under summer conditions.
• The high potential of the night free cooling effect to reduce the cooling loads is shown.
• The cold storage system is almost useless unless the PCM has been fully solidified during the night period.
• The system can prevent successfully the overheating effect of the DSF.

A new type of ventilated facade (VF) with macro-encapsulated phase change material (PCM) in its air cavity is presented in this paper. The thermal performance of this special building envelope is experimentally tested to analyze its potential in reducing the cooling demand during the summer season in the Continental Mediterranean climate. Two identical house-like cubicles located in Puigverd de Lleida (Spain) were monitored during summer 2012, and in one of them, a ventilated facade with PCM was located in the south wall. Six automatized gates were installed at the different openings of the channel in order to control the operational mode of the facade. This versatility allows the system to be used as a cold storage unit, as an overheating protection system or as a night free cooling application. The experimental results point out the night free cooling effect as the most promising operational sequence to reduce the cooling load of the cubicle. On the other hand, the thermal resistance of the outer skin of the facade must be increased; otherwise the cold storage system cannot be used efficiently.