Sloan Canyon to Mead 230 kV Rebuild

Boulder City, Nevada

In 2017, the California Independent System Operator (CAISO) identified electric transmission limitations and congestion on the Sloan Canyon-to-Mead transmission line, increasing the cost of delivered power and dimming the prospects for future solar development in southwest Nevada. Grid congestion on the 15-mile transmission line limited its capacity to deliver electricity without exceeding thermal, voltage, and stability limits needed for reliability. This inefficient delivery of electricity led to increased energy costs in the region. To eliminate these constraints, CAISO authorized the rebuild and upgrade–the first transmission approved congestion project for energy flow out of the CAISO region.

CAISO estimates that the 10-month project, which was completed in December 2020, will save ratepayers $180 million over the 40-year life of the project.

Project Benefits


  • Generates cost savings over time

  • Improves reliability

  • Provides access to lower-cost energy

  • Supports state clean energy goals

  • Encourages renewable energy development

Key Project Highlights:

  •      15 miles of 230 kV transmission line upgraded
  •      1st transmission congestion project for energy flow out of the CAISO region