20210920PAC to Bayer 117-1_5_TSRQ2687SIS.pdf

System Impact Study Report

Network Integration Transmission Service Request System Impact Study Report

Completed for
xxxxxxxxxxxxx
(“Transmission Customer”)
Proposed Transmission
xxxxxxxxxxxx WYONORTH - PACE
Network Resource
Q2687 - AREF # 89371855 240 MW
September 2019

System Impact Study Report
xxxxxxxxxxxxxxx i September 2019 AREF # 89371855
Table of Contents
1.0 Description ...................................................................................................................................................... 1 2.0 Scope of the Study .......................................................................................................................................... 1 3.0 Study Assumptions ......................................................................................................................................... 1 4.0 Transmission/Distribution Additions ............................................................................................................ 2 5.0 Conclusions ..................................................................................................................................................... 3 6.0 Participation by Affected Systems ................................................................................................................ 3

System Impact Study Report
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1.0 Description
The Transmission Customer submitted a network resource request on PacifiCorp’s Open Access, Same-time Information System (OASIS) for designated network resource status for the 240 MW xxxxxxxxxxx as listed below:
2.0 Scope of the Study
This study evaluates the request for designated network resource for the 240 MW xxxxxxxxxxxx. The study report also identifies any additional Direct Assignment Facilities or Network Upgrades
required to provide the requested service. The study does not identify costs or cost responsibilities.
3.0 Study Assumptions
The following assumptions were considered:
• All granted transmission service requests (TSR) and prior requested TSRs were considered
as well as any associated system improvements
• The Transmission Provider’s Energy Gateway West Segment D.2 (Aeolus – Bridger/Anticline 500 kV line) was assumed in-service, with ancillary improvements shown below:
o New Jim Bridger to Anticline 345 kV line
o New Anticline 345/500 kV transformer
o New Aeolus 500/230 kV transformer o New Latham dynamic reactive device
• All improvements identified in the generator interconnection study, including the Remedial
Action Scheme (RAS) for xxxxxxxxxxxxxxx (xxxx), were assumed to be in-service.
• Per the generator interconnection study for xxxxxxxxx, the Yellowtail South path will be redefined as shown in the table below:

OLD Yellowtail South Definition NEW Yellowtail South Definition
Yellowtail* – Frannie 230 kV line xxxxxxxxxxxx*- Frannie 230 kV line
Yellowtail* – Sheridan 230 kV line Yellowtail* - Sheridan 230 kV line
Yellowtail* – Lovell # 1 115 kV line Yellowtail* – Lovell # 1 115 kV line
Yellowtail* – Lovell # 2 115 kV line Yellowtail* – Lovell # 2 115 kV line
* Represents the measured end
• The capacity on the Yellowtail South path is owned by PacifiCorp (xxx MW) and Western
Area Power Administration (xxx MW).
Queue
OASIS Request Type of
Q2687 89371855 6/25/19 DNR WYONORTH PACE 240 9/1/2020 9/1/2050
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• As network resources in east Wyoming significantly exceed area load, this request was studied for deliverability to the Wasatch Front (PACE) in Utah, the Transmission Customer’s primary load center within the PACE system.
4.0 Transmission/Distribution Additions
The Transmission Customer requested that the transmission service request be evaluated with both
an upgrade option as well as a planning re-dispatch option under Section 8.1 of its Network Operating Agreement (NOA). The following indicates the study findings for each option. Upgrade Option In addition to the facilities identified under Study Assumptions, the following planned network
transmission improvements must be in service in order to grant the requested transmission service with no planning re-dispatch of resources under Section 8.1 of its NOA.
• New planned Anticline to Populus 500 kV line (Energy Gateway sub-segment D.3)
• New planned Path C transmission improvements:
o Loop the existing Populus – Terminal 345 kV line in and out of Bridgerland substation o Build out 345 kV yard at Bridgerland (three new 345 kV circuit breakers and bus work)
o Add a new 345/138 kV 700 MVA transformer at Bridgerland substation
o Complete the breaker and a half configuration at Bridgerland 138 kV substation, including four new 138 kV breakers o Install a new Remedial Action Scheme (RAS) to trip the Bridgerland 345/138 kV transformer for the N-2 outage of the Populus – Ben Lomond #1 and #2 345 kV
lines
o Loop the existing Populus – Terminal 345 kV line in and out of Ben Lomond 345 kV substation, adding three new 345 kV breakers o Add a new 230 kV breaker to the Ben Lomond north 230 kV bay to complete the breaker and a half configuration, including bus work and transformer retermination
work
• Limit Yellowtail South path to 500 MW. The Yellowtail South path will be reduced by 125 MW to 500 MW from the current 625 MW limit; this includes Western Area Power Administration’s transmission rights of xxxx MW which will be unaffected by this change.
This is not a WECC rated path.
All of the aforementioned projects are PacifiCorp planned facilities, so no Facilities Study is necessary.
NOA Section 8.1(a) Interim Planning Re-dispatch Option Transmission Customer can also elect to exercise its right to interim planning re-dispatch
procedures under Section 8.1(a) of its NOA. Section 8.1(a) states that, to the extent transmission
system upgrades are necessary to accommodate Transmission Customer’s request to designate a xxxxxx as a network resource, and the Transmission Provider has already identified as part of its long-term transmission plan upgrades that would allow the requested resource designation, no
System Impact Study Report
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Facilities Study is necessary. Rather, Transmission Provider would grant designation in the interim
while the planned facilities are being constructed, provided Transmission customer complies with the scheduling requirements of NOA Section 8.1, including that its schedules will not exceed its current network transmission rights. Once the identified planned facilities are constructed and additional transmission capacity is created, Transmission Provider will grant additional network
transmission rights to Transmission Customer to fully accommodate the requested designation
without limitation.
If Transmission Customer elects to use Section 8.1(a) of the NOA for the xxxxxxxxxx resource, and assuming the facilities listed in Section 3.0 of this study (including Energy Gateway D.2 and ancillary facilities) are in-service, Transmission Provider may designate xxxxxxxxxx as a network
resource beginning on the Transmission Customer’s requested effective date of November 30,
2020. Doing so will require Transmission Customer to follow the scheduling requirements of Section 8.1 of its NOA, including limiting its schedules to no more than its existing transmission rights until the transmission improvements identified in this Section 4 above are in-service. Before designating the xxxxxxxxxx resource as a network resource, Transmission Customer must notify
Transmission Provider in writing that it elects and agrees to comply with Section 8.1(a) of the
NOA. Once the planned facilities listed in the “Upgrade Option” section above are constructed and additional transmission capacity is created, Transmission Provider will grant the Transmission Customer’s requested additional xxx MW of network transmission rights without limitation.
5.0 Conclusions
As identified in section 4.0, certain planned upgrades are required in order to provide the requested transmission service unless Transmission Customer notifies Transmission Provider in writing that it elects and agrees to comply with Section 8.1(a) of the NOA.
If the Transmission Customer notifies the Transmission Provider in writing that it elects to use its NOA Section 8.1(a) planning re-dispatch protocol, the request will be granted on the requested effective date provided that all improvements identified in the associated generation interconnection agreement and Energy Gateway D.2 line are completed and in-service.
6.0 Participation by Affected Systems
Western Area Power Administration is an affected system.