DATC

Duke American Transmission Co.


San Luis Transmission Project

Duke-American Transmission Co. is supporting Western Area Power Administration in its proposal to build a new 62-mile, high-voltage electric transmission line to connect Western’s transmission system with the Bureau of Reclamation’s San Luis Unit pumping and generating plant near Los Banos, California. The San Luis Unit is a key component in delivering water to central valley water agencies and farmers, and the transmission project is intended to minimize expected power delivery cost increases.

San Luis Transmission Project facts at a glance

  • 62-mile line to connect Western’s transmission system near Tracy with the Bureau of Reclamation’s San Luis Unit pumping and generating plants near Los Banos
  • 500,000-volt, high-voltage transmission line with substations at both ends
  • Project intends to optimize the use of an existing transmission line corridor

Economic, reliability and public policy benefits

The San Luis Transmission Project is the least cost and most reliable long-term solution for local water agencies and California electric users. Specifically, the proposed transmission line will enhance delivery of low-cost Western power for use to transport federal water in the San Joaquin Valley, central coast and to Bay Area water agencies and farms. The project will:

  • Limit water cost increases. Avoids long-term, variable added transmission service costs, which would increase water costs for customers and local farmers.
  • Enhance reliability. Strengthens the transmission corridor between the Tracy and Los Banos areas and enhances delivery of energy and water supplies.
  • Maximize efficiency while minimizing footprint. Building the line at a higher voltage maximizes use of an existing transmission corridor, which would minimize costs and environmental impacts.
  • Enable renewable energy. The increased capacity strategically positions the San Joaquin Valley for expansion of renewable energy projects and expands transmission access and flexibility to help the state meet renewable energy and greenhouse gas reduction goals.
  • Strengthen the state’s transmission system. The line would enhance the movement of electricity from Southern California to Northern California. It would improve transmission system reliability in the central valley and help prevent major outages.

Project need

Western is required by law to provide reliable, electric transmission service to the Reclamation and its customers. Western’s transmission contract with Pacific Gas & Electric for delivery of San Luis Unit power at the federal Central Valley Project is expiring, and Reclamation requested that Western develop the SLTP to replace the expiring contract.

Duke-American Transmission Co. has an active Transmission Service Request with Western for enough capacity to support developing and upgrading the project from 230 kV to 500 kV. Working with Reclamation, its water contractors (represented by the San Luis & Delta-Mendota Water Authority) and DATC to build the line may provide additional benefits to water customers and stakeholders across California.

Support is strong and growing

More than 45 water and leading farm groups support development of the San Luis Transmission Project, which increases transfer capability between northern and southern California, increases reliability, enhances options for adding renewable generation and optimizes use of a constrained corridor.

In addition, in August a group of 12 San Joaquin Valley legislators voiced support to the California ISO to advance the 500-kV San Luis Transmission Project.

Timeline

  • Location: Central Valley of California