Numerical Study on Geometric Parameter effects of Power Generation Performances for Segmented Thermoelectric Generator

Thermoelectric generator (TEG) is a promising option in waste heat recovery with various advantages including nonmoving components, very low operating noise and overall high stability. However, low power generation efficiency of TEGs is still concerned for application in wider fields. The objective of the present study is to investigate the parameters affecting the performance and efficiency of segmented TEG. The physical parameters including length ratio, length-to-area ratio and thickness of conducting plate were considered. In addition, the effect of varying hot side temperature was analyzed. Performance of segmented TEG was compared based on the power generation and conversion efficiency. The results of the investigation showed that increasing Bi2Te3 length in the segmented TEG made up of Bi2Te3 and SiGe increased the maximum power generation and efficiency. As length-to-area ratio increased, the power generation decreased, however, efficiency increased slightly. In addition, as the hot side temperature increased from 150 degrees C to 650 degrees C, the power generation and efficiency both increased. Power generation and efficiency of segmented TEG increased when the conducting plate thickness was increased. The power generation and efficiency were 39.2% and 51.9% higher for TEG with asymmetrical element than TEG with symmetrical element showing that asymmetrical element would be better option for same thermoelectric element volume.