Performance analysis of a thermoelectric power generator under volumetric constraint

The efficiency of a thermoelectric power generator can be optimized through proper sizing of the device geometric configurations. In the present study, pin length optimization of the thermoelectric generator for a fixed total pin volume is carried out and the pin length maximizing the device efficiency is formulated. The influences of temperature ratio, defined as the upper junction temperature divided by the lower junction temperature, and the figure of merit, defined as Z = α²/KR, on the device efficiency and output power operating at the optimum pin length are examined. It is found that a unique temperature ratio exists which maximizes the efficiency of the thermoelectric device with the optimum pin length.