LS Power’s affiliate, Great Basin Transmission LLC, has begun work on a $1 billion project in development for a decade. The South-West Inertie Project-North (SWIP-North) is a 500 kV, 2GW transmission line between Idaho and Nevada. Nevada Governor Joe Lombardo joined the groundbreaking ceremony of the 285-mile transmission line. 

POWER Engineers, a unit of WSP Global, is the engineer of record and has completed almost 75% of the design by late 2024. The project scope also includes expansions at the Midpoint and Robinson Summit stations and new series-compensation equipment on SWIP-North and the existing One Nevada line, which operates with NV Energy’s system.

The project broke ground on September 3 in Ely, Nevada. It will serve as the missing link in a high-voltage corridor between Idaho’s Magic Valley and Las Vegas. Together with two existing transmission lines, the completed corridor will total 576 miles. 

Idaho and California have different uses for the transmission corridor. California grid planners want to use the SWIP-North to access the Idaho wind power moving south. Consequently, Idaho Power will use 500 MW moving north from the Desert Southwest to help meet the state’s growing power demands. 

The project was first conceived in the 1980s, and LS Power acquired developmental rights in 2005.

In May 2024, the Energy Department reported committing about $331 million to advance the project, which was then set to begin in 2025 and be completed by 2027. 

Around November 2024, the California Independent System Operator (CAISO), the state’s grid operator, set the capital cost at $1.23 billion, excluding construction financing costs. 

California's stake was largely derived from 1000 MW of Idaho wind, which would help reduce congestion on the California-Oregon Intertie and provide a route for excess solar power generated in the state to move north.

Idaho Power will own the interest of carrying 250 MW and hold rights to another 250 MW for the next four decades. 

Mitch Colburn, utility vice president of planning, engineering and construction, explained, “SWIP-North will help Idaho Power meet growing energy demands and reduce costs for our customers by connecting Idaho Power to the Desert Southwest’s low-cost energy resources.”

For Idaho Power, the project can help mitigate a 154 MW deficit in 2028 and a 384 MW deficit in 2029.