Oncor proposes 138-kV line to meet growing demand from gas development

Oncor Electric Delivery on March 25 submitted an application to the Public Utility Commission of Texas (PUCT) for a double-circuit 138-kV line in Upton County, Texas, to meet growing oil and gas demand in the area.

“The proposed transmission line project is located in an area where (a) rapid load growth, primarily attributable to oil and natural gas load, is occurring and (b) existing transmission and distribution facilities are being utilized at or near maximum capacity,” the company said in the application (PUCT Docket No. 42221).

Atlas Pipeline Mid-Continent WestTex is installing new gas processing facilities, the Edward Gas Processing Facility, in Upton County, Oncor said.

“The proposed transmission line project is needed to provide safe and reliable electric service to the Edward Gas Processing Facility and other future facilities in the area,” the company said.

The 9.9-mile Benedum to Centralia project will connect into the Lower Colorado River Authority’s (LCRA) existing Midkiff to Crane 138-kV transmission line at the Benedum switching station and extend 138-kV transmission facilities to serve new load near Oncor’s new Centralia substation. Oncor would build the transmission line and the Centralia substation while LCRA would build the Benedum switching station.

The transmission line is estimated to cost $9.3m and the substation facilities are estimated to cost $4.5m.

The cost to LCRA to build the Benedum substation is estimated to be $5.5m.

Though Oncor’s Upton substation is only 10 miles away from the Edward Gas Processing Facility, Oncor said due to primary distribution voltage and distance, adequate voltage levels cannot be maintained for service of the new plant.

“Additionally, distribution service from the existing Upton station cannot satisfy the motor starting requirements of the new plant,” Oncor said.

The company also evaluated the alternatives: serving the gas processing plant from a proposed new substation about six miles from the plant connected to a 138-kV Sharyland Utilities transmission line, which Sharyland said did not have sufficient capacity to serve the additional load; and building a 138-kV line from the existing Sharyland 138-kV line to the Centralia substation, which encountered the same problem with respect to capacity on the Sharyland line.

The company expects to begin construction in July and energize the project in October, according to the proposed schedule. Right-of-way and land acquisition is scheduled to begin in June and conclude in July; engineering and design began in November 2013 and is expected to conclude in June; and material and equipment procurement is expected to begin in April and end in July.

Oncor’s current standard for new single- and double-circuit 138-kV construction is concrete or steel monopoles.

The route crosses lands utilized for different uses including oil/gas development; rural residential; and agricultural uses such as cropland, pastureland, and ranchland. The topography of the area is level. The vegetation is mostly scrubland with cropland and prairies.

Oncor retained URS Corp. to prepare the environmental assessment for the project.

The company needs to obtain permits or approvals from the Texas Department of Transportation for crossing a state roadway; a storm water pollution prevention plan; and a cultural resources survey, to be developed with the Texas Historical Commission. Consultation with the U.S. Army Corps of Engineers will follow PUCT approval of the project. 

About Rosy Lum 525 Articles
Rosy Lum, Analyst for TransmissionHub, has been covering the U.S. energy industry since 2007. She began her career in energy journalism at SNL Financial, for which she established a New York news desk. She covered topics ranging from energy finance and renewable policies and incentives, to master limited partnerships and ETFs. Thereafter, she honed her energy and utility focus at the Financial Times' dealReporter, where she covered and broke oil and gas and utility mergers and acquisitions.