SCE proceeding with Tehachapi project while awaiting answer to petition to modify

Southern California Edison (SCE) is moving forward with a limited list of construction and related tasks for the portion of the Tehachapi Renewable Transmission Project (TRTP) that will extend through the city of Chino Hills, Calif., as it awaits a response to its petition for modification (PFM) of the July 11 order directing it to place Segment 8A underground (Docket No. 07-06-031).

“While the PFM is pending, SCE will proceed with demolition of the existing structures, ordering long lead time materials and real property acquisitions,” an SCE spokesperson told TransmissionHub Sept. 12, adding that some of the work related to the actual construction of the TRTP segment cannot be performed “until the PFM has been decided and the [California Public Utilities Commission (CPUC)] confirms that the system should be built with the voltage control equipment included in the original design.”

An SCE officials speaking at a ceremony in Chino Hills on Sept. 6 said the towers at the center of the controversy would begin coming down around Sept. 24.

In the PFM filed Sept. 9, SCE asked the CPUC for permission to install voltage control equipment because the highest rated cross-linked polyethylene (XLPE) cable available that can be used in the 500-kV application is rated at 550 kV. In addition, SCE noted that undergrounding the transmission line will cause an increase in the transmission line charging current that could, in some cases, cause the voltage on the system to exceed its 550-kV rating.

The utility stated that studying the possibility of changing the basic insulation level (BIL) rating for the line, as directed by the CPUC in its July order would significantly delay the in-service date of the TRTP, perhaps as late as 2019.

By undertaking a limited scope of work while it awaits a response to its petition, “SCE is attempting to reduce the length of the delay to the overall Tehachapi project,” the spokesperson said.

There is no specific time frame for the commission to respond to the PFM. However, responses to petitions for modifications must be filed within 30 days of the date that the petition was filed. Further, if granted permission by the administrative law judge, SCE may reply to responses to its petition for modification.

When completed, the 250-mile, $2.5bn, 500-kV project will be capable of moving up to 4,500 MW of renewable energy from wind and solar installations in the state’s renewable-rich Tehachapi area to the load pockets of the Los Angeles basin.

SCE has called the project “a critically important, high-voltage transmission line, the timely completion of which is essential for California’s progress toward its aggressive renewable energy goals.”

SCE is a subsidiary of Edison International (NYSE:EIX).