Experimental investigation of thermal and electrical performance of TEG-mPCM honeycomb boards for RC building roofs

In this study, the integration of thermoelectric generators (TEGs) with microencapsulated phase change material (mPCM) honeycomb board for combined power generation and thermal management in reinforced concrete (RC) roof applications was experimentally investigated. Two mPCM configurations with melting points of 28 °C and 43 °C were examined under various solar heat gain conditions (400, 600, 800, and 1000 W/m²). The results showed that the 43 °C mPCM configuration achieved superior power generation, with a peak output of 108 mW/m², compared with 78 mW/m² for the 28 °C. Both configurations exhibited bidirectional energy harvesting capabilities, generating reverse currents during nighttime hours. Energy ratio analysis revealed that the 43 °C configuration performed better at high heat gains (0.98 × 10⁻³ at 1000 W/m²), whereas the 28 °C configuration was more efficient at moderate heat gains (0.44 × 10⁻³ at 600 W/m²). The findings offer insights for optimizing building energy efficiency by selecting the mPCM melting point tailored to specific climatic conditions and building requirements.