138kV Transmission Overhead Project



    Transmission planning studies determined that the loss of two critical 138kV transmission lines and the failure of several substation loads is likely in the summer and winter. Rebuilding both of the transmission lines would decrease the impedance of the lines such that the voltage drop at two of the substations would remain within acceptable limits, a no-load loss would be expected, and extended winter outage lengths due to cold-load pick-up would be avoided.


    The LUZCO project team rebuilt approximately 29.4 miles of 138kV lines, with a conductor capable of carrying 1200 and 2000 amps, respectively, under summer emergency conditions to increase reliability. The existing wood h-frame line was rebuilt with new wood pole equivalent (WPE) steel h-frame structures with steel crossarms. Three hundred seventeen structures were removed and replaced along with the conductor. In addition, existing shield wires were replaced with two (2) new Optical Ground Wires (OPGW).