Carbon nanotubes (CNTs) present themselves as a viable material for on-and off-chip interconnect material due to their unique electrical, thermal and mechanical properties. The electrothermal properties of CNTs, including high Young's modulus, resiliency and low thermal expansion coefficient offer great advantage for reliable and strong interconnects, and even more so for local and global on-chip interconnects. With aggressive scaling, on-chip interconnects contribute to power consumption and heat build-up due to their increasing parasitics with scaling which detriment overall energy efficiency of circuits. CNTs present an opportunity to address these challenges and provide solutions for reliable and energy efficient signal and power/ground interconnects. In this work, we investigate the electrical and thermal properties of CNTs based on analytical models for interconnect-level simulations. We investigate the performance of horizontally aligned CNTs as global interconnects and report on their performance.