Following open meeting, PUC of Texas commissioner raises questions involving proposed 138-kV line

Public Utility Commission (PUC) of Texas Commissioner Kenneth Anderson Jr., in a March 8 memorandum, requested that certain questions be addressed regarding the settlement stipulation that was filed last month by Brazos Electric Power Cooperative, PUC staff and the City of Frisco in connection with a proposed 138-kV transmission line.

The stipulation agreement would route the proposed Brazos Electric line underground in Frisco, Anderson noted.

“Having reviewed the evidence and heard party statements at the March 3, 2016 open meeting, I believe the stipulation agreement contains numerous uncertainties and unknowns that should be addressed before approving an underground route,” he said. “I therefore request that the parties address the following questions in testimony or other competent evidence to be filed in the docket for the commission’s consideration when it next considers this matter.”

As TransmissionHub reported, Brazos Electric in January 2015 filed an application to amend its certificate of convenience and necessity (CCN) to build a transmission line and substation, known as the Stonebrook Transmission and Substation Project, in order to address the need for increased transmission services to Denton County Electric Cooperative, doing business as CoServ Electric. The project is located entirely in Denton County in both Frisco and the Town of Little Elm.

The PUC administrative law judges (ALJs) last November issued their proposal for decision, approving the project and recommending that it be built on Route 5. However, discussions between the parties have resulted in the stipulation concerning the stipulation route as the route for construction of the project, the parties added.

The parties agree that the PUC should amend Brazos Electric’s CCN to allow the construction and operation of the project on the stipulation route, according to certain terms.

The parties also said that they agree that the settlement is in the public interest and that a reasonable alternative for the proposed transmission line is the stipulation route, defined as and composed of a hybrid route of underground and overhead transmission line segments, including: Tap 1 – Segment 8 – Segment 7 – Segment 5 – Segment 4 – Segment 3 – Segment 2 – Substation North.

All stipulation route segments are located underground, with the exception of Segment 2, which is located partially overhead and partially underground.

The stipulation route is estimated to cost about $24.5m, and is a new approximately 2.9-mile, 138-kV transmission line extending west from an existing Oncor Electric Delivery Company 138-kV transmission line tap to a new Stonebrook substation, the parties added.

On cost savings, Anderson said in his memorandum that questions include:

  • The parties assert that undergrounding the line will result in $9.8m in cost savings. A portion of that amount is based in part on lowering design requirements. What portion of cost savings is attributable to lowering design requirements? What facts support the assertion that Brazos Electric’s initial design for underground transmission in its application was overdesigned? If the underground construction was overdesigned, what are the benefits to overdesigning the system?
  • The proposal for decision reflects that Brazos Electric estimated the cost for overhead “Route 5” at $5.6m, while the settlement stipulation assumes $6m for the cost of an overhead line built along Route 5. What accounts for that approximate $400,000 discrepancy?
  • Would USDA Rural Utility Service funding be available for the incremental cost of underground transmission lines for a project in Frisco? If so, in what amount?

On facilities construction, he said that questions include:

  • The exact length of the overhead portion of the stipulated route is not specified in the stipulation agreement. What is the length of the overhead segment(s) and where will the overhead segment(s) be?
  • The stipulation agreement is unclear whether the agreement to coordinate civil construction applies to the entire underground length of the transmission line or only the length that coincides with Frisco’s water line installation. Is there a portion of the transmission line for which there will be no shared civil construction? If so, is the full cost of any Brazos Electric share of construction costs reflected in the stipulation agreement’s cost estimate?

On reliability, Anderson said that questions include:

  • Neither the stipulation nor the supporting testimony address the reliability of the stipulated underground route. What reliability concerns does the underground route raise?
  • What is the useful life for the 138-kV line build underground compared to overhead placement?
  • There is no evidence that Brazos Electric has ever built, operated or maintained an underground high voltage transmission line. What concerns does Brazos Electric’s lack of experience with underground facilities raise and how will Brazos Electric address those concerns?

Anderson also listed questions concerning public interest and other considerations. For instance, if the PUC does not find undergrounding necessary, what do the parties propose to cover the remaining balance of the incremental cost of undergrounding other than uplifting the cost to all ratepayers, he asked.

About Corina Rivera-Linares 3295 Articles
Corina Rivera-Linares, chief editor for TransmissionHub, has covered the U.S. power industry for the past 16 years. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines. She can be reached at