Phase change materials for energy-efficient buildings

Developing innovative energy-efficient and low/zero-carbon materials are key areas in which the building sector can meet carbon reduction targets. A possible solution is to use phase change materials (PCMs). These are... [ view full abstract ]

Developing innovative energy-efficient and low/zero-carbon materials are key areas in which the building sector can meet carbon reduction targets. A possible solution is to use phase change materials (PCMs). These are chemicals that can control temperature fluctuations and increase thermal mass in buildings thanks to their ability to store and release thermal energy during phase change processes. Thanks to this control of temperature fluctuations, the energy demand associated with heating and cooling buildings is reduced.

At the present, PCMs are not widely used in commercial applications. One of the reasons is due to the difficulty in incorporating them into the built environment. This research explored the use of highly absorbent lightweight aggregate as a media to encapsulate PCMs and incorporate them into construction materials. Three PCMs with different working range temperature were used. The efficiency of the loading method was studied by varying the PCM to aggregate ratio and loading time. Additionally, lightweight aggregates containing the PCMs were coated with several coating agents. Cement mortars containing coated and un-coated aggregates, and previously loaded with PCM, were made to study the compatibility between the lightweight aggregates, coating agents and cement matrix. The mechanical and thermal properties of the manufactured mortars were tested. Mortars mixes with the best performance were selected for subsequent research, which will develop innovative construction materials to increase people’s wellbeing by increasing thermal comfort for occupants in buildings.