Western’s Transmission Infrastructure Program and a group of electricity providers in Arizona have committed to build a large-scale transmission project in Arizona’s Maricopa and Pinal counties. The project will connect a renewable-rich zone south of Phoenix, Arizona, with the Palo Verde market hub, a major electrical trading hub in the western United States. Financed through Western’s authority to borrow funds from the U.S. Treasury, the project will increase transmission capacity to deliver renewable energy, primarily solar, to consumers in Arizona, southern Nevada and southern California.

Western’s Electrical District 5 – Palo Verde Hub project is a 109-mile transmission project in Arizona, starting at the Palo Verde market hub near Wintersburg in Maricopa County, Arizona, and running southeast to the Electrical District 5 substation south of Casa Grande and near Picacho Peak in Pinal County, Arizona.

Western is financing the entire project, borrowing up to $91 million from the U.S. Treasury under a 2009 borrowing authority amendment in the Hoover Power Plan Act of 1984. Developed in coordination with the Southwest Public Power Resource group, a collection of public power companies that include several Western firm electric and transmission service customers of the Parker-Davis Project, ED5-PVH will add up to 410 MW of bi-directional capacity, primarily renewable energy, to the electric grid, which includes 254 MWs connecting to the vital Palo Verde market hub that serves consumers in Arizona and southern California and Nevada.

ED5-PVH includes portions of two other existing projects plus adding new 230-kilovolt circuits to existing and planned transmission lines. To complete the ED5-PVH project, Western will:

• Purchase transmission capacity rights on the 500-kV Southeast Valley Project transmission line between Western’s Test Track substation and the Palo Verde market, a distance of 64 miles.
• Add 45 miles of new 230-kV transmission line from the Test Track substation to Western’s Electrical District No. 5 substation south of Phoenix. This part consists of:
  • Adding a new 230-kV circuit to an existing Western 115-kV transmission line running from ED5 to Casa Grande substation, which is already scheduled for an upgrade
  • Attaching a 230-kV circuit to a planned SEV Project 500-kV line from Western’s Test Track substation to where it intersects with the existing line

The line is scheduled for completion in 2015.