Hearing to be held May 3 on Rocky Mountain Power’s plan to add wind energy, upgrade transmission system

A telephonic public hearing, which is intended to give Rocky Mountain Power customers a chance to submit testimony for the official case record regarding the company’s plan to add nearly 1 GW of wind energy and upgrade its transmission system, is scheduled for May 3, the Idaho Public Utilities Commission said on April 26.

The company’s proposal calls for the construction, or acquisition, of four wind facilities, as well as the construction of, or modifications to, several transmission facilities, all in Wyoming, the commission said.

The wind facilities outlined in the company’s proposal would provide a total generating capacity of 860 MW, the commission said, adding that three of the facilities have a generating capacity of 250 MW and one is capable of generating 110 MW.

The transmission projects outlined in the company’s proposal are associated with its Energy Gateway West transmission project, which calls for the addition of about 2,000 miles of transmission lines in order to alleviate congestion on Rocky Mountain Power’s transmission system and improve its ability to manage the intermittent load produced by wind, the commission said.

The company has asked the commission to approve certificates of public convenience and necessity (CPCN) for the projects, which are estimated to cost $2bn, the commission said. In addition, the company has requested commission approval for binding ratemaking treatment of the projects, which would allow Rocky Mountain Power to track the costs and benefits of the projects, with the difference recovered from customers through the Energy Cost Adjustment Mechanism until the costs of the new facilities are reflected in customers’ base rates, the commission said.

The $2bn cost estimate for the projects would lead to a rate increase of less than 1.9% in 2021, which is expected to be the first full year of operation of the new wind facilities, the commission said. Rocky Mountain Power’s application indicates that the wind facilities must be operating by the end of 2020 to receive the full benefit of federal production tax credits (PTC), the commission noted.

As TransmissionHub reported, the company, a division of PacifiCorp, said in its 2017 application that it requests CPCNs for these transmission facilities (collectively referred to as the transmission projects), significant portions of which are associated with the company’s Energy Gateway West transmission project:

  • The 140-mile, Aeolus-to-Anticline 500-kV line, which includes construction of the new Aeolus and Anticline substations
  • The five-mile Anticline-to-Jim Bridger 345-kV line, which includes modifications at the existing Jim Bridger substation to allow termination of the new 345-kV line
  • Installation of a voltage control device at the Latham substation
  • A new 16-mile, 230-kV transmission line parallel to an existing 230-kV line from the Shirley Basin substation to the proposed Aeolus substation, including modifications to the existing Shirley Basin substation
  • The reconstruction of four miles of an existing 230-kV transmission line between the proposed Aeolus substation and the Freezeout substation, including modifications as required at the Freezeout substation
  • The reconstruction of 14 miles of an existing 230-kV transmission line between the Freezeout substation and the Standpipe substation, including modifications as required at the Freezeout and Standpipe substations

The first three items listed are collectively referred to as the Aeolous-to-Bridger/Anticline Line; the last three items are collectively referred to as the 230-kV network upgrades; and the transmission projects and the wind projects are collectively referred to as the combined projects, the company noted in its application, which the commission received on July 3, 2017.

Rocky Mountain Power said that the combined projects present a time-limited opportunity to obtain cost-effective generation and build the necessary transmission facilities with minimal impact on customer rates.

The transmission projects are necessary to relieve existing congestion and would enable interconnection of the proposed wind projects into the company’s transmission system, the company said, adding that the wind projects produce zero-fuel-cost energy and federal PTC, which provide significant economic benefits for customers when combined with the transmission projects.

To participate, in the May 3 hearing, individuals may call 800-920-7487 and enter passcode 6674832# when prompted, the commission said in its April 26 statement.

About Corina Rivera-Linares 3286 Articles
Corina Rivera-Linares was TransmissionHub’s chief editor until August 2021, as well as part of the team that established TransmissionHub in 2011. Before joining TransmissionHub, Corina covered renewable energy and environmental issues, as well as transmission, generation, regulation, legislation and ISO/RTO matters at SNL Financial from 2005 to 2011. She has also covered such topics as health, politics, and education for weekly newspapers and national magazines.