Power-Generating Waste Heat Recovery System in an Absorption Refrigerator

This study presents the design and evaluation of a power-generating waste heat recovery system integrated into a kerosene absorption refrigerator for off-grid applications. The system employs thermoelectric generators (TEGs) to convert waste heat from the burner into electricity. Experimental tests under quarter, half, and full load conditions revealed voltage outputs of 6.55–11.32 V, 7.54–8.54 V, and 5.72–8.26 V, respectively, with corresponding temperature gradients of up to 46, 71.2, and 71 °C. Burner temperatures ranged from 232.4 to 111.8 °C. The system achieved a 12 V output within 1–3 h depending on load. Power generation ranged from 5.79–16.02 W, with the maximum output recorded at quarter load. Coefficient of Performance (COP) values varied between 0.7630–0.9919 (quarter load), 0.8558–0.9696 (half load), and 0.8407–1.0142 (full load). Statistical analysis confirmed significant performance variations across load conditions. The results demonstrate that the proposed TEG-based system effectively recovers waste heat, enhances energy efficiency, and provides supplemental electricity for rural communities.