Sharyland Utilities, in a Feb. 26 application filed with the Public Utility Commission (PUC) of Texas, said that it is proposing to add a second 166-mile circuit to each of four single-circuit competitive renewable energy zone (CREZ) 345-kV lines spanning seven Texas Panhandle and South Plains counties.
Following the PUC’s directives to develop electric transmission lines under the CREZ process, Sharyland said that it completed the construction and energization in 2013 of the four lines on private properties in Briscoe, Carson, Castro, Deaf Smith, Oldham, Potter and Swisher counties. The company said that those lines – which include segments between the Tule Canyon, Ogallala, Windmill, AJ Swope and Alibates substations – were built with a single circuit on towers that can accommodate two circuits in accordance with final orders in Docket Nos. 33672, 37902, 38290 and 38750.
The project contemplates installing the second circuit on those same towers and within the same 175-foot-wide right of way (ROW) where the existing lines were built.
The purpose of the project is to add the second circuit to the four existing lines to complete the approved CREZ project in the Panhandle A and Panhandle B CREZs, and increase the capacity of the transmission system so that additional renewable energy can be integrated into the ERCOT market, Sharyland said.
In Docket No. 33672, the PUC found that the major transmission improvements identified in “Scenario 2” of the CREZ Transmission Optimization Study (CTOS) conducted by ERCOT were “necessary to deliver the energy generated by renewable resources in the CREZs, in a manner that [was] most beneficial and cost-effective to the customers” and designated the CREZ zones. Scenario 2 contemplated that the resulting transmission would have the capacity to accommodate an estimated 18,456 MW of generation, Sharyland added, noting that achieving that objective required the lines between Tule Canyon and Ogallala, Ogallala and Windmill, Windmill and AJ Swope, and AJ Swope and Alibates to be double-circuit 345-kV lines.
The PUC designated Sharyland to build the Tule Canyon to Ogallala, Ogallala to Windmill, Windmill to AJ Swope, and AJ Swope to Alibates transmission lines as single-circuit 345-kV lines on double-circuit capable structures in Docket No. 37902, and approved construction of the first circuit in Docket Nos. 38290 and 38750.
Thereafter, Sharyland added, ERCOT filed a study requested by the PUC evaluating the need for a second 345-kV circuit on the “Alibates-AJ Swope-Windmille-Ogallala-Tule Canyon transmission line.” ERCOT’s study indicated that the transmission line did not meet the economic criteria under ERCOT protocols, but that with an additional 300 MW of wind capacity connected at Windmill or Ogallala, installation of the second circuit would meet “ERCOT’s Trial 1 economic criterion.”
In that same report, ERCOT noted that 300 MW of additional wind generation was added at Ogallala after the results of the report had been presented to the ERCOT Regional Planning Group, Sharyland said, adding that a PUC commissioner in a September 2015 memo said that given the dramatic and continued expansion of wind generation in the region, Sharyland should proceed with installation of the second circuit to complete the CREZ project. The commissioners agreed with that proposal, directing Sharyland to file its certificate of convenience and necessity application to install the second circuit.
The second circuit, Sharyland said, will use the approximate 46 miles of existing transmission line ROW between the Tule Canyon and Ogallala substations, the approximate 27 miles of existing transmission line ROW between the Ogallala and Windmill substations, the approximate 47 miles of existing transmission line ROW between the Windmill and AJ Swope substations, and the approximate 46 miles of existing transmission line ROW between the AJ Swope and Alibates substations – about 166 miles total.
Sharyland added that the project does not include any substation reactive compensation or any series elements, such as sectionalizing switching devices or series line compensation. Also, the project does not involve an HVDC transmission line. The company further noted that while the overall typical structure height is about 129 feet for the steel lattice structures and 125 feet for the monopole structures, the final actual height of each structure as installed varies depending on terrain.
The structures to be used in the project were selected, approved and built under Docket Nos. 38290 and 38750, Sharyland said, adding that at the time the structures were selected, the company considered landowner preference, engineering constraints and costs. In its Feb. 26 application, Sharyland proposed to use the vacant position on existing self-supporting, double-circuit capable steel lattice towers and monopoles already built along the project route to suspend the second circuit.
According to the estimated schedule, ROW and land acquisition is set to begin in September and be completed in April 2017, while engineering and design is also set to begin in September and be completed in January 2018. Material and equipment procurement is set to begin in October and be completed in December 2017; and construction of the facilities is also set to begin in October and be completed in May 2018. The facilities are set to start being energized in July 2018, with that process set to be complete in August 2018.
The total project cost is estimated at $77.4m, with the total estimated cost of the transmission facilities being about $61m, and the total estimated cost of the substation facilities being about $16.4m, Sharyland added. The facilities will be financed through a combination of debt and equity.
The project is located within a rural setting, Sharyland said, adding that there are no municipalities crossed by the project route, and land use is predominantly comprised of range and pastureland as well as irrigated cropland. Most of the project area has been impacted by development activities associated with agriculture, residential structures, oil and gas facilities, roadways, and several utility corridors.
Among other things, Sharyland added that the project does not cross or abut any parks or recreational areas, nor is it located within 1,000 feet of any parks or recreational areas.