Probabilistic thermal analysis and phase transition temperature optimization for low-rise residential buildings with temperature-adaptive radiative cooling roofs

This paper conducts an optimization study on the energy performance of applying temperature-adaptive radiative cooling (TARC) coatings as building roofs. To provide guidance for the application of TARC roofs, a method for determining the optimal phase transition temperature of TARC coatings for application in buildings is proposed. Then, the thermal performance of the TARC roofs is analyzed for buildings located in five different climatic zones in China based on the probability density function and cumulative distribution function. Finally, the energy efficiency of the TARC roof and the effect of the phase transition temperature on the energy savings potential of the TARC roof are discussed in detail. The results showed that the TARC roof can address the issue of increased heating loads caused by passive daytime cooling (PDRC) roofs during the heating season. Furthermore, the annual total energy savings potential of the TARC roof is 6.3–23.5 MJ/m² for buildings located in five different climatic zones in China. In addition, the annual energy savings of buildings with TARC roofs can be further improved by 3–7% once the optimal phase transition temperature is adopted.