An experimental and Comparative performance of a thermal electric generator system using different heat exchanger fluids

•Evaluate various fluids’ impact on TEG system performance.•Conducts experiments to assess fluid effects on heat transfer and efficiency.•Compares electrical output, heat absorption, and thermal conductivity.•Identifies the best fluids for maximizing TEG efficiency.•Examines how fluid characteristics affect TEG design and performance. This study investigates the effects of the heat transfer performance of the fluids and their supplied pressure on TEGs’ performance. Consequently, experiments are conducted to evaluate the fluids as mentioned and the impact of various pressures on the bars from 2 to 6. In addition, the TEG’s working temperature is adjusted to adapt each fluid’s characteristics to find the maximum power point tracker. In general, the study’s results reveal that the power of the TEG significantly depends on the features of the fluids. Indeed, freshwater shows superior heat exchange efficiency compared to other liquids. When fixing the temperature of the cold side about 30 °C, the maximum power for the fluids corresponding to the different hot side temperature is 9.8, 30, 35, and 44 W, and for the fluids of water, ethylene glycol, lubricant, and glycerin, respectively. In addition, when the flow rate changes from 1 to 5 L/min, the voltage and output capacity of the thermoelectric device tend to increase gradually. In conclusion, working fluids’ boundary conditions and characteristics dramatically affect the TEG performance.