The Public Utility Commission (PUC) of Texas, in a March 22 order, approved Southwestern Public Service’s (SPS) application to amend a certificate of convenience and necessity for a proposed 345-kV transmission line within Yoakum and Gaines counties.
As TransmissionHub reported, SPS last December filed with the PUC an unopposed stipulation regarding its application.
Consistent with the stipulation, the PUC said in its March 22 order, the approved route for the line is modified route N, comprised of Links 1, 2, 10, 10M, 14, 18, 18M, 34M, 21, 22, 35 and 36. Modified route N is about 27.33 miles long, the PUC said.
As noted in the order, SPS last June filed the application for the proposed line, which would extend to the Texas-New Mexico state line. The proposed line would begin at the Yoakum County substation in Yoakum County, about six miles southeast of Plains, Texas, on County Road 260, and would end at the state line with New Mexico, on State Line Road, about 0.99 mile north of the intersection of County Road 330 and State Line Road in Yoakum County.
The proposed line represents the Texas portion of the Yoakum-to-Hobbs project, which would connect the Yoakum County substation with the Hobbs substation in Lea County, N.M. The PUC further noted that the Yoakum-to-Hobbs project is part of a larger TUCO-to-Yoakum-to-Hobbs project.
In addition to the new line, the Yoakum County substation would be expanded and would require upgrades that include the addition of a 345/230-kV 560 MVA transformer and a 345-kV bus that would accommodate the connection of the proposed 345-kV line.
The PUC also noted that the Southwest Power Pool (SPP) identified the proposed line as needed for reliability in the West Texas/New Mexico area to address loading violations on the underlying network and voltage violations due to insufficient power supply to the network load in the service area.
Further discussing the project’s need, the PUC noted that SPS’ summer load forecast from 2015 to 2023 for the transmission system within the Texas Central plains, Yoakum and Gaines counties and the New Mexico Hobbs and Pecos Valley service areas indicates that there is increasing load growth in the area for the next nine years and supports the need for the additional transmission capacity that the proposed transmission line would provide.
SPS filed 13 alternative routes consisting of a combined 40 links, and parties in the case have agreed to modified route N, the PUC added. SPS would purchase a 150-foot easement – wider in some circumstances – for modified route N, the PUC said.
The proposed line would be built using primarily two-pole tubular H-frame steel structures for tangents and light angles. Three-pole tubular steel structures would be used for high angle structures and dead-end structures, the PUC added.
The total estimated cost to build the Texas portion of modified route N, including substation costs, is about $45.2m. SPS estimated that the cost to build the transmission facilities is about $35.7m. The PUC added that the estimated cost to expand and upgrade the Yoakum County substation is about $9.5m.
The total estimated cost to build each of the 14 routes – including modified route N – range from about $35.4m to about $70m, the PUC said, noting that at a total cost of about $45.2m, modified route N is in the lower end of the range.
While the increase in costs of modified route N over the route initially recommended by SPS is about $9.5m, the project is part of a larger project that extends southwest into New Mexico, and the endpoint of modified route N would result in the portion of the line in New Mexico being shorter. Accounting for that offset, the PUC added, the increased cost of modified route N could be as low as $5.6m in the context of the entire project.
Included in the cost of the transmission line for modified route N are about $1m in estimated mitigation costs associated with potential impacts to Lesser Prairie-chicken (LPC) habitat, the PUC said, noting that the LPC is listed as threatened by the U.S. Fish and Wildlife Service. LPCs have not been documented within the area of the alternative routes, but all of the alternative routes are located within the estimated occupied range +10 miles for the LPC, the PUC said.
The PUC also noted that there are no recreational areas crossed or within 1,000 feet of the proposed centerline of modified route N. Also, that route does not cross any listed or determined-eligible historical or archaeological sites, and there are no such recorded sites located within 1,000 feet of the centerline of the route.
The PUC further noted that the aesthetic impacts of the proposed line have been considered and minimized to the extent reasonable.
Additionally, the proposed line would cause only minimal and short-term impact to soil, water and ecological resources. The PUC also said that the proposed line would have no significant impact, if any, on aquatic/hydric habitat, and would have no significant impact on local wildlife. Furthermore, no impacts to federal or state-listed threatened or endangered species are anticipated.
Among other things, the PUC said that in the event that SPS or its contractors encounter any artifacts or other cultural resources during project construction, work is to cease immediately in the vicinity of the resource and the discovery is to be reported to the Texas Historical Commission. Also, SPS is to minimize the amount of flora and fauna disturbed during construction of the line, except to the extent necessary to establish appropriate right of way clearance for the line.
SPS is a wholly owned subsidiary of Xcel Energy (NYSE:XEL).