Experimental investigation of the performance of a thermoelectric generator at various operating conditions

Abstract

Thermoelectric generators (TEG) is the device that can directly convert heat into electricity by the Seebeck effect, which is fascinated for waste heat recovery. An experiment was setup to study the influence of heat flux through the thermoelectric module on the power output and efficiency of a commercial Bi₂Te₃-based thermoelectric modules. The experimental result indicated that the power output evidently increased with the increasing heat flux through the thermoelectric module (TEM), while the conversion efficiency increased significantly at first then the tendency became mild with the increasing heat flux for a given air flow velocity and flow temperature. The temperature differences across the thermoelectric module are almost identical with various air velocity, while the power output and efficiency increased with the increase of cooling flow velocity with a fixed heat flux through the TEM. The power output and efficiency almost linearly decreased with the increase of cooling flow temperature with a fixed heat flux through the TEM and a fixed cooling flow velocity. The maximum output power can be obtained by maximization heat flux without exceeding the upper temperature limit of thermoelectric module.