What are electric transmission lines?

Overall, the state’s electric grid is a network of power generation, transmission lines, switching stations, substations and distribution lines. The transmission lines comprise a majority of what is called the bulk electric system. They function much like the interstate highway system and move large amounts of energy at high voltages from the power generation plants to substations. At certain substations, the energy is converted to lower voltages and from there delivered across lower-voltage distribution lines to customers.


Why are they needed?

An efficient and reliable bulk electric system is dependent upon an adequate number of transmission lines that can move the necessary amounts of power. These lines allow the electric grid to operate reliably and are vital to ensuring access to cost-effective generation resources located far from where the power is consumed.  


Where are Lone Star’s transmission lines located?

Lone Star's transmission facilities stretch from Scurry County, northwest of Abilene, to Navarro County, just south of Dallas.  The transmission line traverses 11 Texas counties:  Scurry, Fisher, Jones, Shackelford, Callahan, Eastland, Comanche, Erath, Bosque, Hill and Navarro.


What is our process of operating and maintaining our transmission lines?

As part of our responsibility as a transmission line owner and operator, Lone Star periodically inspects transmission line structures, equipment, and transmission line easement areas. We perform line inspections on the ground and in the air by helicopter or other aircraft. Typically, the entire line will be patrolled and inspected on the ground at least once per year. On occasion, it is necessary to perform minor repairs and normal maintenance functions, such as replacing insulators. We perform vegetation management on the transmission line easement areas; vegetation management is critical to the safe and reliable operation of the transmission line. Lone Star uses several methods to perform vegetation management including the use of mowers or shredders and herbicides that have been approved by the U.S. Environmental Protection Agency. See our informational brochure for landowners for more information.


What are Lone Star's facility connection requirements?

Lone Star’s facility connection requirements comply with NERC Reliability Standard FAC-001-1 Facility Connection Requirements and document compliance with NERC Reliability Standards, applicable Electric Reliability Council of Texas (ERCOT), and Lone Star planning criteria and facility connection requirements.  Lone Star’s facility connection requirements address functional requirements for:

  • connecting new generation to the Lone Star transmission system;
  • substantially modifying existing generating facilities connected to the Lone Star transmission system;
  • connecting new transmission facilities to the Lone Star transmission system;
  • and connecting new and existing delivery points.

See Lone Star Transmission Facility Interconnection Requirements for detailed information.