Designing high efficiency segmented thermoelectric generators

• Published in: Energy conversion and management 2013-02, Vol.66, p.165-172
• Main Authors: Hadjistassou, Constantinos, Kyriakides, Elias, Georgiou, Julius
• Format: Article
• Language: English
• Subjects: Analytical model; Applied sciences; Coefficients; Computational efficiency; Computational model; Computing time; Efficiency; Energy; Exact sciences and technology; Information technology; Intermetallics; Lead base alloys; Lead tellurides; Segmented; Temperature; Thermoelectric generator; Thermoelectric generators
• ISSN: 0196-8904; 1879-2227
• DOI: 10.1016/j.enconman.2012.07.030

► A design methodology for segmented TEGs is formulated on theoretical modeling. ► The efficiency and geometry of Bi2Te3, PbTe and Bi2Te3PbTe are derived for ΔT=325K. ► Bi2Te3PbTe exhibits an efficiency/ΔT ratio intermediate to Bi2Te3 and PbTe. ► (α¯) and (α˜) Bi2Te3PbTe exhibit a 60–68% thermal resistance match than Bi2Te3 and PbTe. Improving the efficiency of thermoelectric devices is critical to their widespread adoption. Here a design methodology, formulated on computational and analytical modeling, derives the optimum efficiency and geometry of segmented Bi2Te3–PbTe Thermoelectric Generators (TEGs) between ≈298K and ≈623K (ΔT≈325K). Comparisons between the different TEG designs, in terms of the electrical load to TEG electrical resistance ratio (m=RL/RTEG), are simplified thanks to the devised maximum efficiency to temperature gradient (βmax=η/ΔT) metric. Quasi-computational results of βmax show that the collective Seebeck coefficient Bi2Te3–PbTe (α˜) design sustains a higher electrical load in relation to the homogeneous Bi2Te3 and PbTe materials. The average (α¯) and collective (α˜) Seebeck coefficient Bi2Te3–PbTe configurations, in comparison to Bi2Te3 and PbTe, exhibit a considerably higher (60–68%) source and sink thermal resistance matching (ΘTEG=ΘHx). The proposed segmented Bi2Te3–PbTe (α˜) TEG yields a peak efficiency of 5.29% for a ΔT of 324.6K.