MICRO-ENCAPSULATED PHASE-CHANGE MATERIALS FOR LATENT-HEAT STORAGE: THERMAL CHARACTERISTICS

A significant problem of the utilization of renewable energy is the mismatch between the demand and availability. From this point of view, heat storage contributes to the use of renewable energy for the heating and cooling of buildings. Heat can be stored using sensible- or latent-heat-storage techniques. Nowadays, activated concrete structures are used as an alternative cooling-and-heating system. Light-weight timber structures with an equivalent heat-storage capacity can be used instead of these heavy-weight structures. The latent-heat storage using micro-encapsulated phase-change materials (PCMs) represents a way to provide an adequate thermal mass within a small thickness of thermally activated structures. A series of experiments in a lab and test rooms were carried out to investigate the thermal behavior of micro-encapsulated PCMs for building applications. The Micronal (R) DS 5040 X microencapsulated PCM was used as the latent-heat-storage medium in combination with gypsum plaster. Differential scanning calorimetry (DSC) was used for a thermal analysis of the latent-heat storage medium. The storage medium underwent thermal cycling for an assessment of the heat-storage capacity changes during the proposed service life. The floor structure and the plasterboards fixed onto the ceiling and walls of an experimental room with an integrated PCM were thermally activated with capillary tubes. The performance of the system was continuously observed and evaluated.