Possibility investigation of phase change material-impregnated and surface coated cork as an aggregate for building envelope application

Abstract

PCM is a valuable construction material due to its energy efficiency, but leakage during phase changes poses challenges. This study developed a cork energy storage aggregate (CESA) by vacuum impregnating cork with phase change material (PCM) and coating it with polymer and silica fume to address leakage. Experiments confirmed the suitability of CESA as a building material, demonstrating its compressive strength. Thermal analysis via differential scanning calorimetry showed a decrease in enthalpy after PCM impregnation, with CESA with parafol-20Z displaying an enthalpy of 88 J/g compared to the 193.5 J/g of PCM. Despite the reduced enthalpy, CESA aggregates delayed temperature rise effectively in energy storage tests. CESA with paraffin wax showed a 1.48 times temperature-increasing time lag, and CESA with parafol-20Z showed a 1.78 times time lag. These results meant that CESA showed a potential for energy-saving performance when this technology is applied to buildings. Laboratory experiments under varying ambient temperatures further confirmed the significant of CESA heat storage capacity. These findings highlight the importance of selecting PCM based on external temperature and melting point for optimal energy savings, demonstrating the potential of CESA to reduce energy consumption in construction.