Public Service Company of Colorado (PSCo), an Xcel Energy Company, contracted Southwire HV Solutions to provide and install a completely functional 230-kV, XLPE transmission cable system on its Sandown-Leetsdale circuit in Denver. The project included material, labor, project supervision and cable installation equipment.
Southwire supplied and installed 86,284 ft of 2500 kcmil segmental conductor cable, 30 splices, 6 terminations, as well as link boxes, clamps and associated hardware. The completed system was tested with a 24-hour AC soak test. During the 24 hours, Southwire provided Partial discharge (Pd) measurements on all accessories, which passed Xcel Energy's requirements for Pd levels.
The installation route went through a highly congested residential area within the City and County of Denver so coordination between Xcel Energy and Southwire was critical. The duct bank was constructed in the road right-of-ways, requiring permits for lane closures during pulling and splicing operations. Staging areas housed the many large steel reels needed for insulated transmission cables. Accessories that were packaged in crates and boxes also had to be stored to protect the material prior to installation from the harsh weather.
An aggressive installation schedule was used throughout the project. Southwire responded by providing a cable pulling crew and two jointing crews to work in parallel. The installation took place during Denver's winter weather, so crews coped with several snow storms and days with daytime temperatures that were only in the teens.
Southwire and Xcel Energy have partnered on several underground transmission projects and continue to share successes.