Energy Efficient Buildings: How to determine the most suitable PCM and interior environment to maximize energy saving in buildings

摘要

Phase change materials (PCMs), which melt and solidify at a specified temperature range, can be employed effectively to store energy as latent heat of melting in a large number of applications. They can be used to increase thermal mass of buildings by mixing them with the building materials such as gypsum or concrete. In this work, thermal building simulation code (SUNREL) was used to simulate the performance of buildings. The accuracy of the code was tested against experimental measurements conducted using office size timber constructions with gypsum board used as the interior surface. The gypsum boards, in one of the room, was impregnated with a PCM which melts in the range of 18- 22°C. The SUNREL simulation code was used to simulate the two rooms to assess potential energy saving in summer and winter. In summer each room was assumed to have an identical air conditioner set to a similar cooling power and a controlled similar indoor temperature, which was varied in the simulation within the comfortable level. Also, the effect of using PCMs with different melting temperature was studied. The objective was to find the best combination of indoor temperature and type of PCM that maximize energy saving based on Auckland weather. The results of the simulations show that the selection of indoor temperature has a significant effect on the air conditioning energy that can be saved through the application of PCM. In order to achieve good saving in energy through the application of PCM, it is necessary to set the indoor temperature to 22°C or higher. Winter simulations showed similar results as discussed in the paper.