20171109PAC to Staff 3rd Suppl UT-40 DPU 8 1-8.pdf

1407 W.North Temple
ROCKY MOUNTAIN Salt Lake City,UT 84116
POWER
A DIVISION OF PACIFICORP
October 27,2017
Erika Tedder
Division of Public Utilities
160 E 300 S,4th Floor
Salt Lake City,UT 84114
e_tedder@utahgov (C)
RE:UT Docket No.17-035-40
DPU 8th Set Data Request (1-8)
Please find enclosed Rocky Mountain Power's Responses to DPU 8th Set Data Requests 8.1-8.8.
Also provided on a Confidential CD are Confidential Response DPU 8.8 and Confidential
Attachment DPU 8.1.
Confidential information is provided subject to Public Service Commission of Utah (UPSC)
Rules 746-1-602 and 603.
If you have any questions,please call me at [phone].
Sincerely,
Jana Saba
Manager,Regulation
Enclosures
C.c.:Dan Kohler/DPU _d_ktoehle_r@day_markea._com_(C)
Aliea Afnan/DPU [e-mail]_rg(W)
ibower@,daymarkea.com (W)
Dan Peaco/DPU dyeaco@_daymarkeasom (C)(W)
Kevin Higgins/UAE khiggins@energygtratco_m (C)
Neal Townsend/UAE (C)(W)
Gary A.Dodge/UAE [e-mail] (C)
Philip Hayet/OCS [e-mail] (C)
Béla Vastag/OCS bvagt_ag@utah_.gov(C)
Sophie Hays/UCE (C)
Kate Bowman/UCE kate@utah_cleanenergYArg (C)(W)
Emma Rieves/UCE [e-mail](C)(W)
Lisa Tormoen Hickey/[e-mail] (C)
Mitch Longson/Interwest n1_longson@rnc2b_._com (C)
Nancy Kelly/[e-mail](C)
Jennifer Gardner/WRA (C)
Penny Anderson/WRA (W)
Peter J.Mattheis/Nucor p rn srnxblaw.corn (C)
Eric J.Lacey/Nucor (C)(W)
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.1
DPU Data Request 8.1
During the October 11,2017 technical conference,the Company stated that the most
recent area reliability study did not show a need for the proposed transmission project to
meet reliability standards.Please confirm this statement,and provide the most recent
applicable area study.
Response to DPU Data Request 8.1
The statement was intended to convey that the Company is currentlyin compliance with
the North American Electric Reliability Company (NERC)TPL-001-4 standard,
Transmission System Planning l'erformance Requirements.PacifiCorp's most recent
TPL-001-4 annual assessment is provided as Confidential Attachment DPU 8.1.
Confidential information is provided subject to Public Service Commission of Utah
(UPSC)Rule 746-1-602 and 746-1-603.
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.2
DPU Data Request 8.2
During the October 11,2017 technical conference,the Company responded to questions
regarding the assumed transfer capability increase of 750 MW (see,e.g.,Link Testimony
lines 156-161,Vail Testimony lines 72-83,Company's Response to DPU 4.1).The
Company acknowledgedthat the 750 MW value is not calculated in the WECC study
provided in response to DPU 4.1,and that 750 MW value is the result of an informal
analysis conducted by the Company in preparation for filingthe Application.Finally,the
Company stated that it is currentlyconducting a formal analysis of the increase in transfer
capability that will be provided to parties in the coming weeks.
(a)Please confirm the accuracy of the representationof the Company's statements made
above.
(b)Please confirm that the Company has not yet provided any studies supporting the
claimed transfer limit increase of 750 MW.
(c)Please provide all analysis and documentationof the "informal"study conducted by
the Company concluding that the transfer capability would increase by 750 MW with
the proposed transmission project.Include in this response all internal memoranda,
reports,presentations,etc.related to this study,as well as all work papers,modeling
results,power flow studies,dynamic-stability studies,etc.
(d)Please provide the anticipated date that the new,formal analysis will be complete.
(e)Please provide the new analysis as soon as it is complete,along with all
documentation,analysis,modeling results,power flow studies,dynamic-stability
studies,etc.associated with the study.
Response to DPU Data Request 8.2
PacifiCorp has completed the preliminaryTransfer Capability assessment studies for the
Aeolus West transmission path,which reflects the increase of transfer capability of 750
megawatts (MW)from east to west across Wyoming.This analysis will be the first set of
studies to be included in the FAC-013-2 Transfer Capability assessment of the path.
For additional study information,please refer to the Company's response to OCS Data
Request 8.1.
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.3
DPU Data Request 8.3
Regarding the Company's study of the increase in transfer limit allowed by the proposed
project (currentlyunderway):
(a)Will this study be submitted to WECC?
(b)Please describe the process for recognition of these results by WECC.For example,
will WECC conduct its own study?Will it adopt PacifiCorp's results and include
them in system studies going forward?
Response to DPU Data Request 8.3
(a)Path ratingi studies for the Aeolus West transmission path for the full Energy
Gateway project were completed in January 2011;therefore,these studies will not be
needed at this time.
(b)PacifiCorp has completed the preliminary Transfer Capability assessment studies for
the Aeolus West transmission path,which reflects the increase of transfer capability
of 750 megawatts (MW)from east to west across Wyoming.This analysis will be the
first set of studies to be included in the FAC-013-2 Transfer Capability assessment of
the path.
While the preliminary Transfer Capability assessment evaluated the simultaneous
interaction between the Aeolus West path and the TOT 4B (Path 38)path,the FAC-
013-2 Transfer Capability assessment will also evaluate simultaneous interactions
between Aeolus West and both the Bonanza West (Path 33)and TOT lA (Path 30)
paths,and potential interaction with TOT 3 (Path 36).As no facilities will be
constructed west of Jim Bridger,an interaction between Aeolus West and Bridger
West (Path 19)and potentiallyPath C (Path 20)and Montana -Idaho (Path 18)will
also be investigated.
In performing the Transfer Capability assessment for the Aeolus West path,a
technical study group will be formed with interested Western Electricity Coordinating
Council (WECC)utilities and a joint study finding will be shared with the WECC
Study Subcommittee (StS).As follow-on to these studies,System Operating Limits
(SOL)studies will be required to meet Peak Reliability guidelines.
For additional study information,please refer to the Company's response to OCS
Data Request 8.1.
1 At the March 30,2010,Energy Gateway West and Energy Gateway South combined project reviewmeeting
participants approved the Energy Gateway Phase 2 Study Plan and agreed that incremental transmission
limitations for transmission segments that are added between stages,will be addressed via SOL (System
Operating Limit)studies.[This same process was previously followedand successfully demonstrated by BPA and
Avista for the West of Hatwai Expansion project.]
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.4
DPU Data Request 8.4
Refer to the Vail Testimony,lines 332-341,stating that the 750 MW increase in transfer
capability allows approximately 1,270 MW of additional wind due to the ability of other
resources to re-dispatch.Refer also to the Company's Response to DPU 4.2(b)
describing the factors considered in the 1,270 MW value.
(a)Please provide the quantitative analysis,calculations,and work papers supporting the
conclusion that redispatch can accommodate 1,270 MW of additional wind capacity
with a 750 MW transfer limit increase.Include in this analysis the assumed
redispatch of other plants by unit to allow the additional wind capacity.Work papers
should be provided in electronic spreadsheet format with formulas intact.
(b)Provide the results of outage simulations referenced in response to DPU 4.2(b)
concluding that system performance meets NERC reliability criteria under these
conditions.
(c)How much additional wind capacity could be accommodated on the existing system
(absent the proposed transmission project)by redispatching existing generators?
Please provide all analysis and documentation supporting this response.
Response to DPU Data Request 8.4
(a)PacifiCorp has completed the preliminary Transfer Capability assessment studies for
the Aeolus West transmission path,which reflects the increase of transfer capability
of 750 megawatts (MW)from east to west across Wyoming with up to 1,270 MW of
new wind resources east of Bridger/Anticline.This analysis will be the first set of
studies to be included in the FAC-013-2 Transfer Capability assessment of the path.
For additional study information,please refer to the Company's response to OCS Data
Request 8.1.
(b)The preliminaryTransfer Capability assessment study report provided for the Aeolus
West transmission path demonstrates that the new transmission system facilities
meets all North American Electric Reliability Corporation (NERC)and Western
Electricity Coordinating Council (WECC)performance criteria under steady-state and
outage conditions.
(c)In utilizing redispatch of thermal resources,zero MW of additional wind generation
can be accommodated on the existing Wyoming transmission system due to low
stiffness factor (short circuit ratio (SCR))considerations.
Low system stiffness factor prevents the addition of new wind resources in southeast
Wyoming without the addition of new transmission facilities.This prudent
engineering practice on the part of PacifiCorp has been confirmed by NERC's
issuance of the "IntegratingInverter-Bases Resources into Weak Power Systems
Reliability Guideline"in June 2017,which describes concerns with adding significant
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.4
levels of inverter-basedresources into weak transmission system.A copy of the
NERC reliability guideline is provided as Attachment DPU 8.4.
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.5
DPU Data Request 8.5
Regarding the approval of the proposed project in other jurisdictions:
(a)Please provide an update of the status of proceedings in all other jurisdictions.
(b)Please provide a schedule for each proceeding,and identifythe date of expected
regulatory ruling for each jurisdiction.
(c)For each jurisdiction,please confirm whether or not approval is required for the
project to go forward.
(d)If the Company does not receive approvals in all other jurisdictions,will the
Application in Utah be withdrawn?
Response to DPU Data Request 8.5
(a)Please refer to the Company's response to subpart (b)below.
(b)Updated schedules for states in which applications have been filed.
Wyoming (Docket 20000-520-EA-17)
-09/25/2017 -Technical conference (Complete)
-11/20/2017-Intervenor direct testimony due
-12/18/2017-Company rebuttal testimony due
-01/17/2018 -Technical conference on 2017R RFP results
-02/05/2018 -Intervenor supplemental testimony due for 2017R RFP results
-02/12/2018 -Company supplemental rebuttal testimony due for 2017R RFP
results
-02/22-28/2018 -Public hearing
-04/30/2018 -Commission order requested
Idaho (Case PAC-E-17-07)
-08/10/2017 -Technical conference (Complete)
-11/20/2017-Intervenor direct testimony due
-12/08/2017-Company rebuttal testimony due (Company requested extension
to 12/18/2017 and all intervenors granted it as of 10/27/2017but the Company
must file its motion to change the schedule with Idaho Commission)
-02/08/2018 -Settlement conference
-02/16/2018 -Intervenor supplemental testimony due for 2017R RFP results
-03/02/2018 -Company supplemental rebuttal testimony due for 2017R RFP
results
-03/12-15/2018 -Public hearing
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.5
04/06/2018 -Commission order requested
(c)Approval of the certificate of public convenience and necessity (CPCN)application
in Wyoming (Docket 20000-520-EA-17)and the Significant Energy Resource
Decision application in Utah are required for the project to go forward.Although
advance approvals in other states are not technical requirements for the Company to
proceed,receipt of such approvals -or the lack thereof -will be a key factor in the
Company's ultimate decision on whether to proceed.
(d)In the states where approval has been requested,if approval for the CPCN in
Wyoming is not received,the Company would not be in a position to proceed with
the project.
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.6
DPU Data Request 8.6
Refer to the Link Testimony,lines 566-575.Regarding the modeling of the line-loss
benefit in SO and PaR,please provide additional details and documentationregarding
how the 102 GWh benefit was actually implemented in the model.For example,was
there a shape applied to the energy savings?Was load simply reduced by l 1.6 MW each
hour?If so,how were the load savings distributed across the system?
Response to DPU Data Request 8.6
The loads in Wyoming Northeast were reduced by 11.61 megawatts (MW)each hour
once the transmission project is in service to reflect the line loss benefits.
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.7
DPU Data Request 8.7
Refer to the Company's Response to OCS 1.11.Please explain why the LGIA request
for the McFadden Ridge II project was withdrawn only one month after it was filed.
Response to DPU Data Request 8.7
The 2011 Integrated Resource Plan (IRP)indicated 2,100 megawatts (MW)of new wind
resources would be added to PacifiCorp's generationportfolio beginning in 2018.New
wind resources were scheduled to be built in phases over several years to meet state
renewable standards.The Large Generator Interconnection Agreement (LGIA)request
for McFadden Ridge II was filed October 21,2011,as part of the development process to
meet this goal.As the IRP was progressing through the state commission approval
process in the fall of 2011,the timing of new wind construction projects began to look
less certain.The LGIA was withdrawn November 21,2011,to avoid the accrual of costly
engineering studies until more certainty could be attainedregarding the timing of future
wind projects.
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.8
DPU Data Request 8.8
Confidential Request -Refer to the Company's Confidential Attachment to OCS 1.22
(16'Supplemental).
Confidential Response to DPU Data Request 8.8
In reference to the Company's 16*Supplemental response to OCS Data Request 1.22,
specifically Confidential Attachment OCS 1.22 lst Supplemental,spreadsheet
"Generation Curtailment Data CONF",tab "Thermal 2012-2017",the Company responds
as follows:
The data used in the "Thermal 2012-2017"work sheet was extracted from the
Company's "Pi"database for the referenced timeframe.The hourly values for the
maximum capacity (PMAX)were extracted from the "Pi"database for each unit.The
hourly values for actual generation output were extracted from the "Pi"database.
O
O
O
O
O
17-035-40 /Rocky Mountain Power
October 27,2017
DPU Data Request 8.8
Confidential information is provided subject to Public Service Commission of Utah
(UPSC)Rule 746-1-602 and 746-1-603.