Ten West Link Transmission Line

Sargent & Lundy supported the development of new interstate 500-kV transmission line project as independent engineer

Ten West Link Transmission Line
Tonopah, Arizona, to Blythe, California
Client: Lotus Infrastructure Partners

Project Highlights:

  • The 500-kilovolt transmission line is recognized by the Department of Energy and Biden-Harris administration as a critical infrastructure project for the Desert Southwest region.
  • The transmission line is a Federal Energy Regulatory Commission Order 1000 project designed to increase the regional capability of the electrical grid of delivering new renewable energy, enhance operational flexibility, and strengthen reliability in the Southwest.
  • The project accommodates the interconnection of future renewable energy resources in both Arizona and California to the bulk transmission grid, helping modernize and diversify the region’s infrastructure.
  • The transmission line’s selected route reduces impacts to the surrounding area, including the Kofa National Wildlife Refuge and tribal lands, by maximizing the use of designated utility corridors and existing access roads to conserve resources.

Project Description:

Ten West Link thumbnail | Sargent & LundyThe 500-kV Ten West Link transmission line spans 125 miles between Southern California and central Arizona. The Lotus Infrastructure Partners project supports the region’s potential for large-scale solar energy development in creating an interconnection to the bulk electric grid that helps the two states reach their renewable energy standards and carbon reduction goals.

This project is sponsored by the California Independent System Operation Corporation and will oversee the operation of the transmission line once it is in service. The transmission line is designed for 3800 amps continuous with 25% series compensation station (SCS) provided to the line, which will increase power transfer capacity and improve voltage stability.

Project Scope:

Sargent & Lundy is the project’s independent engineer and has been hired to perform technical due diligence reviews during major steps of the project life cycle, identify and mitigate potential design flaws, and verify use of good utility practice. As IE, the firm has performed review activities for the transmission line design, the series compensation design, environmental permitting approaches, the construction contract and the operations and maintenance agreement. Sargent & Lundy also provided a financial model assessment to support project financing and recommendations, where appropriate, to help prospective stakeholders mitigate potential issues and concerns.

Additional review activities included:

  • Design criteria and electrical studies.
  • Structural design for tower and tubular steel including tower testing.
  • Transmission line design using PLS-CADD.
  • Hardware and assembly design.
  • Project material and construction specifications.
  • Transmission line foundation and anchor design.
  • Constructability and feasibility reviews.
  • SCS schematic and communication drawings.
  • SCS cable schedules.
  • SCS calculations.
  • SCS civil, physical, and structural designs.
  • Environmental permitting.
  • Facility inspections for acceptance testing, quality, and expediting.
  • Equator principles assessment.

Sargent & Lundy’s role during the construction phase includes onsite IE construction monitoring and services that observe compliance to both project design and good utility practice in support of IE project financing certifications. Deliverables include:

  • Monthly IE site inspections of project construction.
  • Monthly construction status reports.
  • Construction production reporting reviews.
  • IE support reviewing construction requests for information to identify conformance with project design documents.
  • Project invoice reviews to verify alignment with the project financial model.

Schedule Milestones:

  • Approved Project Sponsor Agreement: December 2015
  • Certificate of Public Convenience and Necessity: November 2021
  • Construction Start: November 2022
  • Expected Commercial Operation: Quarter 1 of 2024

Read more about this project here.
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