20180329PAC to Staff UT OCS Set 16 (1-11) (1).pdf

1407 W.North Temple
ROCKY MOUNTAIN Salt Lake City,UT 84116
POWER
A OfVISION OF PACIFICORP
March 26,2018
Béla Vastag
Office of Consumer Services
160 East 300 South
Salt Lake City,Utah 84111
b_vvastag@utahgov (C)
RE:UT Docket No.17-035-40
OCS 16th Set Data Request (1-11)
Please find enclosed Rocky Mountain Power's Responses to OCS 16th Set Data Requests 16.7-
16.8 and 16.11.The remaining responses will be provided separately.Also provided is
Attachment OCS 16.8-1.Provided on the enclosed Confidential CD is Confidential Attachment
OCS 16.8-2.Confidential information is provided subject to Public Service Commission of Utah
(UPSC)Rule 746-1-602 and 746-1-603.
If you have any questions,please call me at [phone].
Sincerely,
Jana Saba
Manager,Regulation
Enclosures
C.c.Erika Tedder/DPU dpudatarequest utah.gov gedder@utahiov(C)
Dan Kohler/DPU [e-mail](C)
Dan Peaco/DPU [e-mail] (C)(W)
Aliea Afnan/DPU [e-mail] (W)
[e-mail](W)
I hilip Hayet/OCS [e-mail] (C)
Gary A.Dodge/UAE [e-mail] (C)
Phillip Russell/UAE [e-mail] (C)
Kevin Higgins/UAE [e-mail] (C)
Neal Townsend/UAE [e-mail](C)(W)
Kate Bowman/UCE [e-mail](C)
Emma Rieves/UCE [e-mail](C)(W)
Lisa Tormoen Hickey/[e-mail] (C)
Mitch Longson/Interwest [e-mail] (C)
Nancy Kelly/[e-mail](C)
Jennifer Gardner/WRA [e-mail](C)
Penny Anderson/WRA [e-mail] (W)
Peter J.Mattheis/Nucor [e-mail] (C)
Eric J.Lacey/Nucor [e-mail] (C)(W)
William J.Evans/UIEC [e-mail]
Vicki M.Baldwin/UIEC [e-mail](W)
Chad C.Baker/UIEC [e-mail] (W)
17-035-40 /Rocky Mountain Power
March 26,2018
OCS Data Request 16.7
OCS Data Request 16.7
Refer to the Company's response to UIEC 2.3.Ms.Crane has stated that PacifiCorp is
willingto accept risks for the loss of receiving full PTC benefits associated with
PacifiCorp's performance.Please confirm that the Company is not willingto absorb the
risk of loss of receiving full PTC benefits if the Company operates the new wind units in
the round robin scheme?Please fully clarify the risks that the Company is and is not
willingto accept concerning the round robin scheme.
Response to OCS Data Request 16.7
The use of a "round robin"scheme does not,by itself,indicate that the Company's
performance was less than adequate or that the Company is or is not solely responsible
for the lost production tax credits (PTC)during the rotating curtailment.An assessment
of the circumstances that brought about the need to use a "round robin"scheme and the
Company's performance in light of those circumstances would be necessary to determine
the responsibility.
Regarding risks that the Company is and is not willing to accept concerning a "round
robin"scheme,the Company objects to the request on the basis that it calls for
speculation.Any outcome that is less than favorable would need to be assessed as to
whether the outcome was a result of Company's performance or whether an outcome was
a result of factors outside of the Company's ability to influence.
17-035-40 /Rocky Mountain Power
March 26,2018
OCS Data Request 16.8
OCS Data Request 16.8
Refer to DPU 12.3.
(a)Why haven't the benefits of adding synchronous condensers to the system to improve
the short-circuit ratio been vetted?Isn't it possible that the combination of adding
synchronous condensers and retiring Dave Johnston early would provide greater long-
term economic benefits to customers,while still providing the ability to add more
wind capacity to the Eastern Wyoming area,compared to adding the 500 kV line?
Please explain.If no analysis has been performed,please explain why not and how
the Company has made any determination of the benefits.Please provide the results
and work papers of all analyses conducted and any documents/reports that were relied
on in evaluating the benefits of adding synchronous condensers.
(b)The response to DPU 12.3 mentions that SVC and STATCOM devices would not
improve the transfer capabilities of the system at thermal limits.Please state if
thermal generationor synchronous condensers could be used to improve the transfer
capability of the system at thermal limits.Please explain.
Response to OCS Data Request 16.8
(a)The benefits of adding a synchronous condenser to the system has not been fully
vetted.Note:with improvement of the selective catalytic reduction (SCR)and
addition of wind,the limitingfactor will become the thermal limits of the lines.
Improvingthe SCR will not increase the thermal limit of a transmission facility.The
current TOT 4A Total Transfer Capability (TTC)is 960 megawatts (MW)compared
to an increased TTC of 1792 MW with the D2 segment in service.
(b)PacifiCorp completed an analysis in November 2017 of the Transmission Assessment
of Dave Johnston Plant Retirement Impacts to New Wyoming Wind Generation
Integration.Please refer to Attachment OCS 16.8-1 and Confidential Attachment
OCS 16.8-2.Study results indicated with the retirement of the Dave Johnston power
plant up to l169 MW of new wind generationcan be integrated in southeast
Wyoming;however,a number of 230 kilovolt (kV)transmission improvements
would need to be added to the system.It is anticipated that the cost of the 230 kV
transmission facilities identified would exceed the D.2 Project transmission facility
costs.
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
March 26,2018
OCS Data Request 16.11
OCS Data Request 16.11
It appears that PacifiCorp's position is that even if wind projects were found to be
completely uneconomic in Eastern Wyoming,the D2 segment would still have to be
constructed by 2024.If this is not an accurate characterization,please clarify and explain
the Company's position.If it is,please explain why under these circumstances,the
Company would be required to construct the D2 segment by 2024.
Response to OCS Data Request 16.11
Independentof the need to integrate additional wind in eastern Wyoming,PacifiCorp has
determined that addition of the D.2 Project (Bridger/Anticline-Aeolus)will provide the
followingreliability benefits to the transmission system:
The D.2 Project transmission facilities will strengthen the overall reliability of the
existing transmission system by providing critical voltage support to the Wyoming
transmission network.
The addition of new transmission lines will mitigate the impact of outages on the
existing system,and will increase the system reliability under the various multiple
contingencies of the TPL-001-4 standard.
-In the event of a line outage,the redundancyprovided by the Project will allow
the Company to continue to meet native load service obligations and continue to
meet other contractual obligations to third parties.
The Projects will improve the Company's ability to perform required maintenance
without significant operational impacts to the system,and will reduce impacts to
customers during planned and forced system outages.
In addition to reliability benefits,the Projects will also:
Increase the transfer capability across Wyoming by 750 megawatts (MW)and enable
interconnection of the proposed Wind Projects;
Provide greater flexibility in managing existing resources and reduce energy and
capacity losses;and
Support the long-term transmission expansionplanning established in the most recent
Northern Tier Transmission Group (NTTG)sub-regional plan.
The D.2 Project has been included in the Company's and region's long-term transmission
plan and will remain an integral component of those long-term plans even if it is not
constructed by 2020 in support of the Wind Projects.