Thermal to electrical closed-loop thermoelectric generator with compact heat sink modules

Abstract In this study, a novel compact heat sink module with water as the working fluid in a closed-loop thermal (Peltier effect) to electrical (Seebeck effect) thermoelectric generator (TEG) is presented. The heat sink thermoelectric generator consists of an input system (TEC) that produces a hot and cold liquid and an output system (TEG) that generates output voltage using the thermoelectric model TEC1-12710. The liquid flow rate of the hot side and the cold side ranges from 0.011–0.049 kg/s, and input voltages of 5 V and 7 V are studied. The number of thermoelectric plates in TEC systems with 2TECs and 3TECs, and in a TEG system with 9TEGs are considered. The results demonstrate that an increase in heat transfer in the hot and cold sides results in increased temperature differences in the liquid, which increases the output power. The experiment indicates that a maximum temperature difference of 14.714°C was obtained in the liquid between the hot and cold sides in the TEC system (input system), resulting in a generated output voltage of 5.44 V from the TEG system (output system). Besides, the optimum mass flow rate of the liquid in the hot and cold sides was 0.034 kg/s and 0.016 kg/s for an input voltage of 5 V, and 0.017 kg/s and 0.011 kg/s for an input voltage of 7 V, respectively, producing the maximum temperature difference and total output power. To increase the heating and cooling capacity by obtaining a greater temperature difference, the number of thermoelectric plates and the input voltage of the TEC system should be considered.