San Luis Valley (SB100)


San Luis Valley Grid Improvements

Xcel Energy is in the process of making improvements to the company’s electric system in the San Luis Valley of Southern Colorado, primarily through transmission system rebuilds, but including improvements to the distribution system, as well.

The multi-year effort, which began in 2016, includes four projects totaling more than 50 miles of transmission line rebuilds. Also included in the effort is significant work on Xcel Energy’s distribution system in the San Luis Valley, including work within several Xcel Energy substations.

In 2016, Xcel Energy invested some $12 million to refurbish and rebuild approximately 27.5 miles of transmission line. The upgrades in 2016 and 2017 generally include new and stronger transmission line structures, new conductor and new optical ground wiring (OPGW), which among several purposes increases the communications capabilities along the transmission system.

The four transmission projects to be completed in 2017 include:

  • A rebuild of 10.7 miles of 69 kilovolt (kV) transmission line from Xcel Energy's Mosca to Moffat substations, including new structures, conductor, and optical ground wiring and communications capabilities. The effort is already underway and will be completed this year;
  • A rebuild of 7 miles of 69 kV transmission line from the Moffat to Mirage substations. The project currently is in design and also will include new structures, conductor, and optical ground wiring and communications capabilities. Construction will take place this summer and will be completed by the end of 2017;
  • A rebuild of 7.7 miles of 69 kV transmission line from the Villa Grove to Kerber Creek substations. Design is being finalized and will include new structures, conductor, and optical ground wiring and communications capabilities. Construction starts this spring and will be completed by the end of the year; and
  • A rebuild of 24.7 miles of 69 kV transmission line from the Alamosa plant to the Fort Garland substation. Construct will begin in 2017, with the project being completed by the end of the year. It will include new structures, conductor, and optical ground wiring and communications capabilities.

Xcel Energy also is looking to make distribution system improvements for the San Luis Valley area, including work within several substations in Alamosa and Del Norte. These improvements will include upgrading high-voltage circuit breakers, protective line relays, power transformers and communications networks.

The transmission and distribution projects, estimated to cost $42 million, will improve electric reliability for customers, and provide cost-effective power. 

Future Plans

Xcel Energy continues to look to the future when it comes to transmission development to enhance electric system reliability customer load-serving capability, and to accommodate development of potential generation resources.

In 2015 and 2016, the company participated in the San Luis Valley Subcommittee of the Colorado Coordinated Planning Group (CCPG), which had the objective of performing analyses and developing plans to improve the transmission system to the north of the San Luis Valley. The first phase of studies verified that, at a minimum, a new 230 kilovolt transmission line from San Luis to Poncha would be a first step to accomplish the objectives. The second phase of studies, which was completed in 2016, identified alternatives for transmission beyond Poncha to enhance reliability and generation export potential from the San Luis Valley to the Front Range.