APS is working to identify locations for a new 230kV substation and three transmission line interconnections to continue providing our customers with safe, clean and reliable electricity. The power lines are needed to serve existing customers and support the economic growth and development in the West Valley. The new substations and power lines would be built in the general area of Northern Parkway between Loop 303 and the Agua Fria River.

We are considering:

• A new 230/69kV substation (e.g., TS-20 or Contrail Substation) located on the customer’s property on the southeast corner of Olive Avenue and Dysart Road.
• Two new 230kV transmission lines connecting the new substation east into the existing El Sol – White Tanks 230kV transmission line or El Sol Substation.
• A new 230kV transmission line connecting the new substation west into the planned TS-2 Substation previously permitted as part of the West Valley South Project.

The new facilities are intended to further our commitment to clean, high quality, and reliable electric service for all of our customers. These new facilities are needed to serve APS customers, including new commercial customers, which promotes economic development for the West Valley.

Although we have the necessary infrastructure to meet current energy needs in this area, the amount of power needed to serve the new commercial customer requires new 230kV infrastructure and will also provide the energy needs for future growth in the surrounding area.

This project will bring direct and indirect benefits to individuals and the community as a whole. Providing safe and reliable electric service enables economic growth, bringing high-end jobs and revenue to the area. This project will improve the power infrastructure in the West Valley, which benefits economic development for surrounding cities in the long term, including:

• The ability to better meet the growing energy needs, and increase the reliability to residents
• Help create new businesses and job opportunities
• Help sustain a larger tax base to better support the communities

Construction is anticipated to begin in the second half of 2022 and the powerlines and substations will be energized in 2023.

Approximately 7-10 miles of new power lines are needed, depending on final route selection.

Existing power lines are often considered opportunities to locate new power lines. Although the existing power poles in this area are not large enough to support the new 230kV power lines for this project, we would take this opportunity to consider rebuilding existing power lines with larger poles that would enable us to consolidate the new 230kV power lines with the existing power lines.

The siting process will evaluate a range of alternatives that may include routes within existing roadway ROW, private property, or a combination of both. Prior to identifying a preferred route APS will consider the availability of land, ownership, cost of ROW in our decision process.

Corridors for 230kV facilities will be approximately 120 feet wide. However, this requirement may be less if the ROW is shared with roadways, utility lines, canals, etc.

APS works with landowners to secure necessary easements. There are a range of restrictions within the right-of-way to ensure the lines can be constructed, operated, and maintained, safely and according to electrical codes.

Placing transmission and sub-transmission voltage power lines underground is significantly more expensive than placing power lines overhead. Actual cost differences depend on various elements, including terrain, project length, environmental concerns, labor, and material differences, etc. An overhead line that spans trenches, washes, or other difficult terrain, may not be compatible for running underground, and would require added time and expense for additional labor and material. Depending on the voltage and the location of the power line and considering the inability to be cooled by the ambient (surrounding) air as in an overhead configuration, underground power lines may require special technology to keep the wires cool. Underground 230kV lines require the cable conduits to be encased in a special concrete slurry, which allows for greater heat dissipation while adding a layer of protection from accidental excavation.

Buried power lines may also extend power outages, as it may take additional time to locate a specific power issue, access the fault and repair it. Additionally, underground systems can be prone to flooding in certain conditions. Typically, lower voltage 12kV (distribution) lines are buried with new developments, as the additional cost to place the lines.