Any protests or responses to DCR Transmission LLC’s (DCRT) application regarding its Ten West Link Transmission Project are due to the California Public Utilities Commission (CPUC) by Nov. 21, the company said in a notice filed with the CPUC.
DCRT noted that it seeks a certificate of public convenience and necessity (CPCN) to build the project, which would run between the existing Delaney substation in Tonopah, Ariz., and the existing Colorado River substation west of Blythe, Calif.
As proposed, the project would span about 114 miles, including 97 miles in Arizona, and 17 miles in California, largely following the existing Devers-Palo Verde (DPV) 500-kV transmission line in an established utility corridor, the company said.
The project is composed of the following segments and would be built within a combination of existing public rights of way (ROWs) and ROWs to be acquired:
- Central Segment (proposed): 113.98 miles
- North Copper Bottom Pass: 4.3 miles
- South Copper Bottom Pass: 5.97 miles
- Alternative Segment: 25.2 miles
The company also said that the major project elements are:
- The project would include the installation of a 500-kV transmission line
- The proposed structures would be steel lattice towers, including self-supporting four-legged tangent towers, guyed towers with a single footing and four support guy wires, and 2-legged H-frame towers as the primary structure types. For areas of conductor tension change, angles, and phasing transpositions, self-supporting four legged dead-end towers would be used. The structures are planned to be between 72 feet and 190 feet in height depending on the span length required and topography, with most being shorter than 130 feet. Span lengths between structures would vary from 600 feet to 2,100 feet depending upon terrain conditions and to achieve site-specific mitigation objectives
- Conductors for the project would be aluminum stranded with a steel reinforced core (ACSR). The AC transmission line would consist of three phases for the single-circuit, including a bundle comprised of multiple conductors per phase. The project would use the “Chukar ACSR” conductor in triple-bundle configuration with 25% series compensation. The minimum conductor height above ground for the line would be 30 feet to 40 feet for most of the route, and 50 feet for the Colorado River crossing
- To protect conductors form lightning strikes, two overhead shield or ground wires would be installed on top of the structures
- The new series compensation system substation would be located under or in very close proximity to the new line, parallel to the existing series compensation system substation associated with the DPV line and located at 59125 Pipeline Road in Arizona. The series compensation substation would be about 46.8 miles from the Delaney substation
The company noted that the CPUC anticipates that it will use the environmental impact statement – to be prepared by the Bureau of Land Management (BLM), which is the primary agency responsible for the federal permitting and environmental review for the project – to fulfill its environmental review obligations under the California Environmental Quality Act (CEQA). The company said that the public may participate in the environmental review of the project through the BLM process, including by submitting comments on the draft EIS, by participating in any scoping meeting or public meetings that may be conducted, and/or by participating in interagency consultations.
The CPUC requires utilities to employ “no cost” and “low cost” measures to reduce public exposure to electric and magnetic fields (EMF), DCRT said, adding that it would implement the following EMF reduction measure(s) for various portions of the project:
- Use more ground clearance with taller 500-kV towers, comparable to the existing Colorado River-Palo Verde towers
- Install 500-kV transposition towers at relatively the same locations as the existing transposition towers for Colorado River-Palo Verde. The transposition towers would ensure optimally phasing for the entire route
- Optimally phase proposed 500-kV transmission line with the existing 500-kV transmission line when possible
According to the application filed last month, the California ISO (Cal-ISO) solicited bids for development of the project through an open, competitive solicitation, and in July 2015, it selected DCRT as the approved project sponsor for the project. The Cal-ISO found that the project would provide: “[s]ufficient economic benefits relative to the estimated cost of the project; [p]otential for policy benefits by increasing the deliverability of renewable generation from the Imperial Valley area; and [r]eliablity benefits by reducing the risk of potential overloading on key transmission paths following the loss of a major common corridor 500 kV import path to California.”
The company also said that it and the Cal-ISO on Dec. 1, 2015, entered into an approved project sponsor agreement, which requires that the project be placed into service by May 1, 2020. DCRT said that it requests a final CPUC decision approving the CPCN by February 2018, in order to meet the in-service deadline.
DCRT estimates that the project’s total capital cost, including interconnection costs, is about $279.6m.
The company also said that the primary project objectives of Ten West include:
- Build an economically and technically feasible, series-compensated 500-kV transmission circuit with a conductor capacity of about 3,200 MW between the Colorado River substation and the Delaney substation
- Facilitate California utilities’ compliance with the renewable portfolio standard by increasing deliverability of renewable resources from Imperial Valley and along the project route, as well as by enabling interconnection and delivery of new (and existing) cost-effective renewable generation in Arizona and California
- Reduce costs to consumers and increase system efficiency by reducing congestion on the West of River and East of River transmission paths, delivering production and capacity cost savings, reducing transmission losses, increasing benefits of the Energy Imbalance Market, increasing competition and operational flexibility, and deferring need for alternative transmission upgrades
As noted in the application, DCRT is a joint venture between Starwood Energy Group and Abengoa Transmission & Infrastructure LLC (ATI); Starwood Energy, through its affiliates, is the managing member of DCRT with a 75% majority ownership interest, while ATI holds a 25% minority ownership interest.