Experimental thermal performance analysis of microencapsulated phase change materials-filled brick hollow configurations for building energy efficiency

Abstract

Improving the thermal behavior of building envelopes plays a significant role in minimizing energy consumption and regulating indoor thermal comfort. The use of phase change materials (PCMs) in wall components offers an important approach to passive heat regulation in buildings. In this regard, the implications of PCM placement for hollow brick structures under real outdoor conditions have been adequately addressed in the literature. This study presents an experimental assessment of the effects of integrating different microencapsulated phase change material (MPCM) configurations into brick hollows on thermal performance, taking into account the same real environmental conditions, while also providing a general approach in terms of energy savings and environmental benefits. The findings highlight that the MPCM additive demonstrates effective performance in reducing peak temperatures and regulating thermal fluctuations. The proposed MPCM-containing bricks (OUT2, IN2 and FULL) provide a maximum advantage of 7.04 degrees C and 4.47 degrees C in minimizing indoor heat gains and losses during the daytime (heating period) and night (cooling period) respectively. Among the configurations tested, IN2, despite having a significantly lower MPCM ratio, provided almost the same thermal and energy advantages as FULL and offered the highest cost-performance efficiency. This highlights the critical role that MPCM placement plays in terms of thermal efficiency. The analyses also show that MPCM efficiency is more pronounced under conditions where solar radiation is concentrated. According to annual heating and cooling energy performance analyses based on experimental measurements, a significant reduction in heat flow in both heat gain and heat loss directions was observed with MPCM integration compared to the reference. The MPCM integration resulted in annual building-scale energy savings of 279-631 kWh by reducing cooling and heating loads by approximately 3.06 kWh/m2 and 12.71 kWh/m2 respectively. Consequently, the building's total annual CO2 emissions decreased by approximately 10.49 kgCO2/m2 & sdot;year. The economic savings achieved by minimizing heatingcooling loads and reducing CO2 emissions reached 88.83 USD. The novelty of this study lies in investigating different MPCM layouts in hollow brick structures under real outdoor conditions, and all findings demonstrate that an optimized MPCM placement can maximize thermal performance and economic return without increasing material usage. Furthermore, it has been shown that the MPCM-brick system offers economically, environmentally sustainability and energy-efficient innovative structural solutions in building envelope designs.