The electro-thermal effects have an important role in the study of metallic Single-Wall Carbon Nanotubes (SWCNTs) for interconnect applications. Experimental data and careful modeling reveal that self-heating is considerably significant in short nanotubes (1 < L < 15µm) under high-bias. The low-bias resistance of micron scale SWCNTs is also found to be affected by optical phonon absorption (a scattering mechanism previously neglected) above 250 K. In this work, we explore the effect of the thermo-electric current (Ihc) caused by the temperature difference along the SWCNTs interconnects (thermo-electric properties). The thermo-electric current effect is studied at low and high lengths of SWCNTs and at different biases.