ICT2014 Abstracts

Unileg thermoelectric generator (U-TEG) is a rising concept in the field of thermoelectric generator (TEG) design. Thermoelements of the U-TEG consist of a semiconductor and a metal instead of combining two n and p type semiconductors as in the conventional TEG designs. Also U-TEGs do not need any further electrodes to make electrical contacts like in traditional TEGs. This is giving added advantages by reducing the number of thermal and electrical contacts in the system. The U-TEGs introduced in this study are based on oxide thermoelectrics for high temperature applications and the power output obtained is about two times higher than the traditional TEG design. For this study Ca₃Co₄O₉ and Al doped ZnO are used as the p and n leg materials respectively, for the traditional TEG design. Constantan and Ca₃Co₄O₉ are used for the U-TEG design. Well-known reduced current approach is used as the TEG/U-TEG designing technique and optimal area ratio suggesting by this approach used as a design parameter. One of the major drawbacks of U-TEG, which is thermal shortening in between hot and cold sides of the generator through high thermal conductive metal is overcome by using above optimal area ratio for metal and semiconductor. Results by the reduced current approach indicate that the power output by a single unicouple according to the conventional TEG design is 0.277 W, while it is 0.468 W by using the U-TEG design. These results are further confirmed by the finite element analysis using COMSOL multiphysics.