J. Vázquez, R. Palacios, M. A. Sanz Bobi

One of the most promising applications of thermoelectricity is the recovery of waste heat for the production of electrical energy. Nowadays several thermoelectric companies manufacture commercial TE modules based on Bi₂Te₃ compounds specially designed to performance as Seebeck modules.

This paper describes a test bench (geometry, materials, measuring equipment…) to analyse the behaviour of commercial TE modules working under different temperature differences. This allows estimating the electric power generated in an application where optimum DT is not achieved. Real applications do not obtain the ideal electric power of TE modules because heat source are usually not controllable, and heat dissipation capacity at the cold side is sometimes limited. Therefore it is not possible to design systems that always behave at the optimal working conditions defined by the manufacturers for a specific module.

The paper shows the results obtained after testing several commercial modules under different working conditions. Plots of voltage, electrical power generated, and efficiency as a function of the current for different heat flows are also included. These results help selecting the most appropriate module for a given application and estimating the real amount of electric energy that will be generated over the expected working cycle.