20180329PAC to Staff UT DPU Set 23 (1-4) (1).pdf

1407 W.North Temple
ROCKY MOUNTAIN Salt Lake City,UT 84116
POWER
A DIVIS10N OF PACIFICORP
March 15,2018
Erika Tedder
Division of Public Utilities
160 E 300 S,4th Floor
Salt Lake City,UT 84114
[e-mail](C)
RE:UT Docket No.17-035-40
DPU 23rd Set Data Request (1-4)
Please find enclosed Rocky Mountain Power's Responses to DPU 23rd Set Data Requests 23.3-
23.4.The remaining responses will be provided separately.Provided electronically is
Attachment DPU 23.4.
If you have any questions,please call me at [phone].
Sincerely,
Jana Saba
Manager,Regulation
Enclosures
C.c.:Dan Kohler/DPU [e-mail](C)
Aliea Afnan/DPU [e-mail] (W)
[e-mail] (W)
Dan Peaco/DPU [e-mail] (C)(W)
Kevin Higgins/UAE [e-mail] (C)
Neal Townsend/UAE [e-mail](C)(W)
Gary A.Dodge/UAE [e-mail] (C)
Phillip Russell/UAE [e-mail] (C)
Philip Hayet/OCS [e-mail] (C)
Béla Vastag/OCS [e-mail](C)
Sophie Hays/UCE [e-mail](C)
Kate Bowman/UCE [e-mail](C)(W)
Emma Rieves/UCE [e-mail](C)(W)
Lisa Tormoen Hickey/[e-mail] (C)
Mitch Longson/Interwest [e-mail] (C)
Nancy Kelly/WRA [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 15,2018
DPU Data Request 23.3
DPU Data Request 23.3
In reference to the Company's response to DPU DR 19.1,and UIEC's DR 2-3,the Round-
Robin technique that will be used to bring the new wind on-line for testing and to meet the
IRS private ruling letter,section 6 (regular basis),please provide the details in Excel format
with intact formulae relating to any curtailments to all other generation in the area as a
result of transmission constraints behind the TOT4A and TOT4B paths until the proposed
transmission projects are completed.Please include in this analysis any loss in synchronous
generation attributes relating to the curtailment of Dave Johnston and Wyodak facilities.
Response to DPU Data Request 23.3
First,on the topic of commissioning the wind turbine generators (WTG),PacifiCorp
currentlyplans to commission all the WTGs for the Ekola,TB Flats,and Cedar Springs
new wind projects exclusivelyusing the 230 kilovolt (kV)transmission system that is
forecast by the transmission provider to have all critical upgrades completed by June 15,
2020.The exact amount of new wind energy that will be placed on the 230 kV system at
any given time during the commissioning duration has yet to be definitively established.
The Company is working with WTG suppliers and engineer,procure,and construct
(EPC)contractors to align this plan.This plan provides for approximately four months of
WTG commissioning duration ,and may require the maximum capacity of the existing
230 kV transmission system if necessary,and the requirements of the transmission
providers "Path Operation Manual".The project team(s)will work with PacifiCorp
energy supply management (ESM)to minimize commercial generation losses to
customers during the WTG commissioning period.If necessary,in the absence of 230 kV
back feed power,mobile generationequipment can be used to commission individual
WTGs.
Second,on the topic of regular operation of the WTGs,hypothetically,if the Company
were in a situation where the new WTGs needed to be operated on a constrained
transmission system,a "round robin"generationrotation plan could be utilized to satisfy
the production tax credit (PTC)requirement that power from the WTGs must be put onto
the grid on a regular basis.During the hypothetical transmission constrained period,the
"round robin"operating plan could result in reduction of the existing generation on the
system,but grid operators would have control of the resource selection option to either
reduce the generation at existing facilities,or new facilities,dependent upon which
decision is in the best interest of customers.Details for implementing this operating
"round robin"scenario and any associated curtailment of Dave Johnston or Wyodak have
not yet been definitively established and are not available in spreadsheet form.
17-035-40 /Rocky Mountain Power
March 15,2018
DPU Data Request 23.4
DPU Data Request 23.4
In reference to the Company's response to DPU DR 19.1,what is the IRS's definition of
"regular basis "in section 6 of the private letter ruling?Please provide a copy of the
IRS's Private Letter Ruling (PLR)20033403.
Response to DPU Data Request 23.4
The correct citation for the Internal Revenue Service (IRS)private letter ruling (PLR)is
PLR 20033403[1].The PLR does not define "regular basis".The recital of the facts
surrounding the PLR's conclusion that the wind turbine generators (WTG)were being
used on a regular basis is set out below.In the event of a delay in the completion of the
transmission line beyond December 31,2020,resulting in a transmission constraint
affecting the ability to operate the wind projects at full capacity,the Company intends to
operate the wind projects in a manner consistent with the facts of the PLR,a copy of
which is provided as Attachment DPU 23.4.
In the event of a delay in the M substation upgrade beyond Date 2,
Taxpayer can nevertheless deliver Project output by making minor and
temporary modifications to its electrical gathering and transmission
facilities.In the event of such delay,Taxpayer intends to utilize the G Kv
tap on the multiple-tap transformers at its two substations,to deliver and
sell output during any delay in the completion of the M substation
upgrade.Once the M substation upgrade is completed,the Taxpayer-
owned transmission lines will be disconnected from the G Kv tap of the
transformers and reconnected to the H Kv tap of the transformers.
Taxpayer expects that utilization of the G Kv taps will allow for delivery
and sale of Mw of electricity,or about %of the Projects maximum
capacity.
In the event of a delay in the completion of the M substation upgrade,the
G Kv tap of the transformers would be used to facilitate testing and
synchronization of each WTG.Thereafter,each of the C WTGs would be
able to produce at its full rated capacity subject only to the limitations of
the M substation prior to the completion of the M substation upgrade,such
capacity limitation estimated to be approximately MW.During any such
delay,Taxpayer expects to operate a fluctuatingnumber of WTGs in a
manner that maximizes operating efficiencygiven the part load
characteristics of the WTGs and the then current site specific wind
conditions.In some instances,fewer WTGs will be operated at or close to
full capacity (D per WTG);in other instances,a larger number of WTGs
will be operated at less than full load.Taxpayer expects to rotate the
operation of WTGs during the time prior to completion of the M
substation upgrade,so that a reasonably consistent number of operating
hours is logged among all of the WTGs for warranty purposes.