20170925Utah_DPU Set 6(1-7).pdf

1407 W.NorthTemple
ROCKY MOUNTAIN Salt Lake City,UT 84116
POWER
A DIVISION OF PACIFICORP
August 25,2017
Erika Tedder
Division of Public Utilities
160 E 300 S,4th Floor
Salt Lake City,UT 84114
[e-mail]
etedder@utahgov (C)
RE:UT Docket No.17-035-39
DPU 6*Set Data Request (1-7)
Please find enclosed Rocky Mountain Power's Responses to DPU 6th Set Data Requests 6.1-
6.7.Also provided are Attachments DPU 6.1 and 6.3 -(1-2).Provided on the enclosed
Confidential CD are Confidential Attachments DPU 6.2 and 6.6 and Confidential Response to
DPU 6.5.Confidential information is provided subject to Public Service Commission of Utah
(UPSC)Rules 746-1-602 and 746-1-603.
If you have any questions,please call Tarie Hansen at [phone].
Sincerely,
Bob Lively
Manager,Regulation
Enclosures
C.c.:Dan Kohler/DPU (C)
Dan Peac/DPU dpeaco daymarkea.corn (C)(W)
Aliea Afnan/DPU [e-mail] (W)
Béla Vastag/OCS bvastag@utahgov (C)
Philip Hayet/OCS [e-mail] (C)
Gary A.Dodge/UAE [e-mail]_m (C)
Kevin Higgins/UAE (C)
Neal Townsend/UAE [e-mail](C)(W)
17-035-39 /Rocky Mountain Power
August 25,2017
DPU Data Request 6.1
DPU Data Request 6.1
O &M Expense.What is the current property tax expense for the WTGs that are
proposed to be repowered?What will the estimated incremental property tax be after the
WTGs are repowered?Please provide in Excel format with intact formulae.
Response to DPU Data Request 6.1
Please refer to Attachment DPU 6.1 for an estimate of property taxes associated with all
existing property for each of the wind projects for which repowering is proposed.Note:
these estimates are based upon 2016 property tax assessments and 2016 property tax
rates.Incremental property taxes have not been estimated on a project-specific basis.
17-035-39/Rocky Mountain Power
August 25,2017
DPU Data Request 6.2
DPU Data Request 6.2
General.Please provide monthlycurtailment data for the five-yearperiod beginning
January 1,2011 through December 31,2016 for the Wyodak and Dave Johnston
generatingplants,respectively.For each curtailment incident,please provide an
explanation of the reason for each respective curtailment at both Wyodak and Dave
Johnston during the five-year period.Please provide your response in Excel format with
intact formulae where applicable.
Response to DPU Data Request 6.2
Please refer to Confidential Attachment DPU 6.2.
Curtailments on Wyodak and Dave Johnston generationwere required to operate within
the TOT 4A transmission limits.
Confidential information is provided subject to Public Service Commission of Utah
(UPSC)Rule 746-1-602 and 746-1-603.
17-035-39 /Rocky Mountain Power
August 25,2017
DPU Data Request 6.3
DPU Data Request 6.3
O &M Expense.For the same period referenced in DR 6.2,please provide O &M expenses
(totals)in Excel format with intact formulae for Wyodak and Dave Johnston,respectively.
Response to DPU Data Request 6.3
Please refer to Attachment DPU 6.3-1 for the Dave Johnston operations and maintenance
(O&M)expenses for years 2011 through 2016,and Attachment DPU 6.3-2 for the Wyodak
O&M expenses for years 2011 through 2016.
17-035-39 /Rocky Mountain Power
August 25,2017
DPU Data Request 6.4
DPU Data Request 6.4
General.For the same period referenced in DR 6.2,please provide the contribution
capacities for Wyodak,Dave Johnston,Glenrock I,Glenrock III,RollingHills,Seven
Mile Hill I,Seven Mile Hill II,High Plains,McFadden Ridge,and Dunlap I in Excel
format with intact formulae.
Response to DPU Data Request 6.4
The Company has interpreted "contribution capacities"to be requesting the capacity
contribution values as defined in PacifiCorp's 2017 Integrated Resource Plan (IRP),
Volume II,Appendix N.Based on the foregoing assumption,the Company responds as
follows:
Capacity contribution values,represented as a percentage of resource capacity,are a
measure of the ability of resources to reliably meet demand.PacifiCorp establishes
capacity contribution values for forward-lookingplanning purposes.These values are
calculated by assessing the ability of resources to produce system energy in those hours
with the highest loss of load probability (LOLP),based on a forecast of generation and
LOLP events.Capacity contributions are not applicable to historical periods with actual
system conditions where load is met,and therefore,capacity contribution values are not
available for the period referenced in DPU Data Request 6.2 for any of the listed
generatingfacilities.For forward-planning purposes,PacifiCorp assumes Wyodak and
Dave Johnston have capacity contribution values of 100 percent.For all other listed wind
facilities,PacifiCorp's forward planning assumes Wyoming wind resources have capacity
contribution values of 15.8 percent (2017 IRP,Volume II,Appendix N,Table N.1).
17-035-39 /Rocky Mountain Power
August 25,2017
DPU Data Request 6.5
DPU Data Request 6.5
O &M Expense.Please provide documentation for the warranty terms and agreements for
the repowered WTGs for both GE and Vestas generators.Please provide supporting
documentation.
Response to DPU Data Request 6.5
Please refer to the Company's response to DPU Data Request 1.3,subparts 1 and 4.
Confidential information is provided subject to Public Service Commission of Utah
(UPSC)Rule 746-1-602 and 746-1-603.
17-035-39 /Rocky Mountain Power
August 25,2017
DPU Data Request 6.6
DPU Data Request 6.6
O &M Expense.As part of the Company's due diligence to repower the selected WTGs,
please provide the estimated annual O &M expense over the useful life of both GE and
Vestas WTGs,including the followingrespective components of the repowered WTGs
once the warranties have expired.Please provide supporting documentation in Excel
format with intact formulae similar to OCS DR 1.40.
(a)Rotor blade
(b)Gearbox
(c)Hub
(e)Yaw bearing maintenance (includingany crane services)
(f)Generator
(g)Brake
(h)Slip ring (includingany crane services)
(i)General maintenance
(j)Balance of system maintenance
Response to DPU Data Request 6.6
Note:the subpart references in this request omits subpart (d).The Company's response
uses the same subpart references as provided by the Division of Public Utilities (DPU)
above,and therefore also omits subpart (d).
The Company objects to this request as requiring development of a special study or
information not maintained in the ordinary course of business.Without waiving this
objection,the Company responds as follows.
Please refer to Confidential Attachment DPU 6.6,which provides estimated annual
operations and maintenance (O&M)costs for the remaining life of the projects for each
wind project underthe repowering scenario.
Please also refer to the Company's response to DPU Data Request 2.7.The Company
does not budget O&M expenses to the level of individual components of the wind turbine
generators or distinguish between general maintenance and balance of system
maintenance.
Confidential information is provided subject to Public Service Commission of Utah
(UPSC)Rule 746-1-602 and 746-1-603.
17-035-39 /Rocky Mountain Power
August 25,2017
DPU Data Request 6.7
DPU Data Request 6.7
Installation Costs.As part of the installation of each repowered WTG at each of the
proposed wind repowering sites,will the yaw bearings and slip rings be replaced?
Response to DPU Data Request 6.7
Yes,the Company's repowering projects will include entirelynew nacelles,hubs,and
rotors.The yaw drive system,includingyaw bearings,as well as slip rings upon which
the yaw brakes slide upon,are components of the nacelle and will be replaced with new
equipment.Other slip ring components within the wind turbine generator include the
pitch slip ring mounted on the gearbox and the rotor slip ring on the generator.These slip
rings will also be replaced with the new nacelles.