Synthesis and evaluation of phase change material suitable for energy-saving and carbon reduction of building envelopes.

Phase change materials (PCMs) reduce building energy consumption, but practical errors often occur due to material mismatches with the application environment. In this paper, taking Guangzhou as an example, to prepare PCMs with a phase transition temperature (T P) close to 26 °C, the Schrader equation is used, and therefore capric acid (CA) and stearic acid (SA) are selected as raw materials. The experimental results show that at a mass ratio (CA/SA) of 9:1, the PCMs can form a eutectic structure with T P and enthalpy of 24.9 °C and 157.3 J/g, respectively. Furthermore, the simulation results confirm that in the whole life cycle the energy-saving rate of proposed PCMs in Guangzhou is high at about 20 %. The study also provides recommendations for optimizing PCMs use in the hot summer and warm winter climates, i.e. on the outside of the envelope, especially on the west wall and roof, increasing the PCMs amount can better save energy. These results are a guideline on building envelope energy efficiency by using PCMs, which can be applied in the optimization of PCMs selection in different climatic zones. [ABSTRACT FROM AUTHOR]