Effects of temperature-dependent thermal properties and the side leg heat dissipation on the performance of the thermoelectric generator

Abstract

Thermoelectric power generation is an important technology in the field of energy conversion, which contributes to the goal of carbon neutralization. The prediction accuracy of thermoelectric generator's (TEG) performance is critical to optimize the design and carbon emission evolution. In this paper, a novel one-dimensional model is developed with comprehensive consideration of the Joule heat, conduction heat, Thomson heat, temperature-dependent properties and side leg dissipation. The numerical solution of the proposed model is compared with the available experimental data and theoretical results. The comparison between the proposed model and experimental data for output power and efficiency of TEG are 3.0–12.0% and 0.9–17.5% respectively, when the temperature difference is within 68–149 K. This implies that the developed model exhibits an improved accuracy, as the published models commonly possess a deviation greater than 20% for the temperature difference higher than 103 K. It is also found that the temperature-dependent properties and side leg heat dissipation have a pronounced effect on TEG performance, when the temperature difference exceeds 68 K. The most influential factor leading to the uneven distribution of temperature and heat flux is the temperature-dependent properties of thermoelectric material, and followed by Thomson heat.