Numerical method for calculating latent heat storage in constructions containing phase change material

In Denmark, cooling of office buildings during summer contributes significantly to electrical consumption. The use of phase change material (PCM) can help to reduce overtemperatures during summer and even out temperature fluctuations over the day, hereby reducing both heating and cooling demands in buildings. This paper describes a numerical method for calculating the latent storage performance of building components containing PCM in order to evaluate the impact on heating and cooling demands. The developed method was implemented in the whole-building hygrothermal simulation software package BSim (Wittchen et al., 2008). The paper also describes comparisons between laboratory measurements on a specific building component containing PCM and results obtained with the developed simulation model. Finally, the paper presents some simple calculations and a detailed case study.