Southwest Intertie Project

On Line Tubular Guyed-V Structures

Project Description

The Southwest Intertie Project (SWIP) is a 500kV AC transmission line being developed by LS power and its subsidiaries. In total, it will run more than 500 miles from Twin Falls, Idaho to Las Vegas, Nevada.

Through a partnership with NV Energy, the 235-mile portion of the One Nevada Line (ON Line) is under construction in Nevada from Ely to northern Clark County. The other parts of the line include a 275 mile project from Ely, Nevada to Twin Falls, Idaho called SWIP North and the Southern Nevada Intertie Project (SNIP), a 60 mile project from Clark County to Eldorado Valley, Nevada.

Important characteristics of SWIP:

• LS Power designed an innovative tubular guyed-V transmission tower (see photo above) with the following ecological advantages:
  • Through a reduction in the number of cross members and perch deterrents on existing cross members, the towers protect prey species like sage grouse by minimizing perching opportunities for raptors.
  • In contrast with typical transmission towers, which require four foundations, the guyed-V towers require only one, limiting the footprint associated with each tower, and in turn reducing construction time, equipment, and labor, resulting in fewer disturbances to sensitive plants and wildlife.
• The ON Line project received a $343 million loan guarantee from the U.S. Department of Energy. This is the first time the DoE has provided a loan guarantee for a transmission project.
• Transmission of renewable energy: SWIP will allow wind, solar, and geothermal resources in Nevada to be developed. Solar Reserve, a solar energy developer, has signed a 25-year power purchase agreement with NV Energy for a 110 megawatt solar power plant that will transmit power through ON Line.
• Buy-in from the conservation organization Nevada Wilderness Project (NWP)
  • NWP worked with the developers in tower design and route selection, thus avoiding important habitat for sage grouse and desert tortoise.
  • NWP sponsored the "SWIP trip" hosted by hiker Adam Bradley, when participants walked the length of the SWIP prior to any line construction, blogging, taking video and bringing awareness to the project. A documentary, "Walking the Line: New Energy in the Old West," was created from his footage.
• LS Power is funding a study on sage grouse impacts to help find out what the real impacts are as the line is being built and after it's been installed.

Current Status: ON Line will be in service by the end of 2012. The other segments of the SWIP line are in late stage development.

Resources

• LS Power/Great Basin, LLC website
• Nevada Wilderness Project's SWIP site
• SWIP Trip documentary, "Walking the Line: New Energy in the Old West"
• Southwest Intertie - ON Line Map
• Southwest Intertie Fact Sheet
• Southwest Intertie Handout - Aug 2011

Organizations: Great Basin Transmission, LLC; LS Power; NV Energy, Nevada Wilderness Project
Location: Nevada, Idaho
Planning Phase: Planning (tower design, community engagement); Operation/Maintenance (monitoring/reporting)
Written by: Alison Berry – This e-mail address is being protected from spambots. You need JavaScript enabled to view it

Last Updated: September 21, 2011