Influence of pin material configurations on thermoelectric generator performance

Thermoelectric generator with new pin configurations is considered to enhance device efficiency and output power. The thermal and the electrical conductivities of the thermoelectric generator pins are modified to vary along the pins length. Thermodynamics analysis of the thermoelectric generator with new pin configurations is carried out and device efficiency and output power are compared with those of uniform pin material thermoelectric generators. The performance of purposed thermoelectric generator is assessed incorporating the operating temperature parameter (θ=T2T1, where T is the junction temperature of thermoelectric generator, and T1 corresponds to the high temperature source and T2 is the low temperature source) and the external load parameter (RL/R0, where RL is the external resistance, and Ro is the reference electrical resistance of the device - R0=Lσ0,nA is the reference resistance, in which L is the pin length, σ0,n is the reference electrical conductance, and A is the pin cross-sectional area). It is found that the purposed pin configuration enhances the thermoelectric efficiency and the output power. The external load parameter maximizing the output power does not maximize the thermal efficiency of the device for given temperature parameters. In this case, the value of the external load parameter becomes small as the device efficiency and output power increases.