Substation at sunset


Transmission Line Projects

Irvington-East Loop 138 Kilovolt (kV) Transmission Line

Tucson Electric Power (TEP) is developing plans for a new transmission line to help serve growing energy needs. The project would help Davis-Monthan Air Force Base satisfy its energy resiliency requirements and improve electric reliability for customers in Tucson.

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Irvington to Kino 138-Kilovolt Transmission Line and Kino Substation Projects

Tucson Electric Power (TEP) has proposed building a new 138-kilovolt (kV) transmission line and substation and upgrading existing facilities in the City of Tucson to strengthen electric reliability for customers and, in particular, to meet growing energy needs in the area of South Kino Parkway and East 36th Street.

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Sonoran Substation to Wilmot Energy Center 138 Kilovolt Transmission Line

Tucson Electric Power (TEP) has proposed building a new 138-kilovolt (kV) substation, switchyard, and transmission line south of Tucson to strengthen electric reliability for customers, meet future energy needs in the area and support what will become TEP’s largest local community-scale solar array and battery storage system.

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Irvington Campus Modernization

Reciprocating Internal Combustion Engine (RICE) Generation and Irvington 138-Kilovolt Transmission Line Relocation

TEP is planning to install a flexible, efficient new type of natural gas generator in Tucson that will support the expansion of renewable energy in our community.

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Sundt Generating Station Air Quality Permit Update

To accommodate the installation of efficient new generating resources that result in lower nitrous oxide emissions, TEP has filed an application to modify an existing air quality permit.

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Irvington Campus Planned Area Development

TEP has proposed updated zoning for its Irvington Campus that will support improved operations and efforts to build a more sustainable energy portfolio.

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Rosemont 138 kV

Project contingent on mine approval.

The Arizona Corporation Commission (ACC) voted unanimously in May 2012 to allow construction of a new transmission line to serve the proposed Rosemont Copper mine in the Santa Rita Mountains southeast of Tucson.

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Transmission lines are necessary to allow energy to flow from power plants to major substations.

TEP is committed to strengthening the transmission system, which is the backbone of our electrical grid, and allows customers to power their homes and businesses.

Substation Projects

Harrison Substation

New substation for continued reliability

TEP is proposing to build a new 138-kilovolt (kV) substation at the northwest corner of North Harrison Road and East Speedway Boulevard that will help ensure continued reliability and satisfy customers' future energy needs.

Project Overview

Substation Information

The proposed Harrison Substation is a priority for TEP to ensure capacity and reliability to current and future residential and commercial customers on Tucson's east side. Three existing substations that serve the area are operating at or above capacity.

The proposed substation will connect to the existing 138-kV transmission line located along the south side of East Speedway Boulevard. The substation would improve electric reliability and reduce the frequency and duration of electrical service outages. The substation also would accommodate anticipated future growth in the area. The need for a substation in the area has been identified in long-term transmission plans filed with the Arizona Corporation Commission.

Fact Sheet and Map

If you have any questions regarding this project, please call (520) 884-3642.

Project Archive

Cottonwood Substation

TEP plans to build a new 138 kilovolt (kV) substation and upgrade existing facilities in the City of Tucson to strengthen electric reliability for customers and meet growing electric demand in southwest Tucson.

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Right of Way Projects

Right of Way (ROW) Renewal

Midvale to South Loop 138 Transmission Line ROW Renewal

TEP is applying to renew a right of way for an existing transmission line in the San Xavier District of the Tohono O’odham Nation. This transmission line is an important part of the local electrical system and supports safe, reliable electric service for residents and businesses in the San Xavier District. TEP is seeking to renew the land right, which expires in 2018, with no change in use, location, or width.

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