20241022PAC to Staff 275.pdf

RECEIVED
Tuesday, October 22, 2024
IDAHO PUBLIC
_ ROCKY MOUNTAIN UTILITIES COMMISSION
POWER
A DIVISION OF PACIFICORP
1407 W North Temple, Suite 330
Salt Lake City, Utah 84116
October 22, 2024
Monica Barrios-Sanchez
Commission Secretary
Idaho Public Utilities Commission
11331 W. Chinden Blvd.
Bldg. 8, Ste. 201-A
Boise, ID 83714
monica.barrio ssanchez(apuc.Idaho.gov
S ecretarygpuc.idaho.gov
RE: ID PAC-E-24-04
IPUC Set 18 (275-276)
Please find enclosed Rocky Mountain Power's Response to IPUC Wh Set Data Request 275.
Also provided is Attachment IPUC 275.
If you have any questions, please feel free to call me at(801)220-2313.
Sincerely,
/s/
Mark Alder
Manager, Regulation
Enclosures
C.c.: Eric L. Olsen/IIPA elo(&echohawk.com(C)
Lance Kaufman/IIPA lancekae isg insi hg t�(C)
Matthew Nykiel/ICL matthew.nykielkiamail.com
Brad Heusinkveld/ICL bheusinkveldkidahoconservation.oriz
Thomas J. Budge/Bayer tj&racineolson.com(C)
Brian C. Collins/Bayer bcollins(&consultbai.com
Greg Meyer/Bayer gmeyer(a)consultbai.com
Kevin Higgins/Bayer khiggins ckenergystrat.com(C)
Neal Townsend/Bayer ntownsendkenereystrat.com (C)
Ronald L. Williams/PIIC rwilliams(&hawleytroxell.com
Brandon Helgeson/PIIC bhel eg sonLhawleytroxell.com
Bradley Mullins/PIIC brmullins(a�mwanalytics.com
Val Steiner/PIIC val.steinerna,itafos.com

Kyle Williams/PIIC williamsk(?byui.edu

PAC-E-24-04/Rocky Mountain Power
October 22, 2024
IPUC Data Request 275
IPUC Data Request 275
In its response to Staff Production Request No. 130, the Company provided
schedules for several sub-projects that collectively comprise the Gateway South
(GWS)project. For example, the Company submitted separate schedules for
transmission line segments titled"Element A", "Element B", and"Element C."
The Company also submitted schedules for the substations (named "A1"through
"A5") that connect the transmission elements. Please provide the following
information about these sub-projects:
(a) Please provide a map that depicts all these sub-projects in relation to the entire
GWS project; and
(b) Please elaborate on the interdependencies between each sub-project and the
usefulness of the entire GWS project. For example, please clarify if Substation
A3 must be substantially complete to enable the transmission of power from
Aeolus to Mona, or if the substation is only necessary to take-off power to
other portions of the grid.
Response to IPUC Data Request 275
(a) Please refer to Attachment IPUC 275.
(b) For any transmission line to be energized, the substations at each end must be
constructed, tested, and commissioned. In the case of Energy Gateway South,
this includes the Aeolus substation, the Little Snake and Coyote series
compensation stations, and the Clover substation. All must meet the necessary
commissioning requirements before any part of Energy Gateway South can be
energized. The Aeolus and Clover substations serve as the energy sources,
while the Little Snake and Coyote stations are series compensation stations
that control voltage when all three elements of Energy Gateway South are
energized.
Energization will begin from either the Aeolus or Clover substation (Element
A or C), extending to the nearest series compensation station, where testing
will take place between those two locations. Once this testing is complete,
Element B between the Little Snake and Coyote stations will be energized and
tested. Finally, the remaining Element A or C will be energized and undergo
final testing.
For Element D, upgrades were required at both the Mona and Clover
substations. After completion, the existing lines between these two substations
were reconductored and energized, followed by the Huntington line being
looped into the Clover substation and energized.

PAC-E-24-04/Rocky Mountain Power
October 22, 2024
IPUC Data Request 275
Recordholder: Brandon Smith
Sponsor: Todd Jensen