Power consumption of model houses with and without PCM plaster lining using different heating methods

Thermal behaviour and power demand of two container model houses were studied. One of them was equipped with plaster lining with incorporated PCM microcapsules, and the second one served as refer-ence during two successive winter periods. In the first winter period of 2019/20, an electric radiator was applied for heating the houses during the daytime, and then they were let cool down from evening to the next morning. The dynamic thermal behaviour and power demand of the model houses were investi-gated during the heating up periods, then in a quasi-thermal equilibrium, as well as along their sponta-neous cooling down process at changing environmental temperatures. The indoor and environmental air temperatures, internal and external wall surface temperatures were collected by data logger during the whole winter periods for both model houses. Through the second winter period of 2020/21 the same methodology was used; nevertheless, the model houses were heated by air-air heat pumps. The perfor-mance coefficient (COP) of heat pumps was compared to the electric radiators. The estimated COP showed significant correlation with the temperature differences between the outdoor and indoor air tem-peratures, considerable worsening from COP = 3.1-3.4 to COP = 2.0-2.1 with increasing temperature drop to be overcome by the applied air-air heat pumps. However, there was no considerable dependence observed between the reference and PCM plaster lined houses. Equations were suggested to estimate the power demand in quasi-thermal equilibrium for both model houses and both heating methods as a function of the temperature differences between indoor and outdoor air. The power demand of PCM plaster lined model house compared to the reference house was lower by 10.3 % and 7.0 % using electric radiators or heat pumps, respectively, throughout the whole winter period, considering a medium tem-perature drop of 20 degrees C through the walls.(c) 2023 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).