20080912PAC to Staff 1-21.pdf

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September 10, 2008
Neil Price
Deputy Attorney General
Idaho Public Utilties Commission
472 W Washington
Boise, ID 83702-5983
RE: P AC-E-08-03
IPUC Data Request 1-21
RECEiVED
Z008 SEP I I AM 10: Sa.
IDAHO P ìC
UTIL1TIES co ISSION
201 South Main, Suite 2300
Salt Lake City, Ut 84111
Please find enclosed Rocky Mountan Power's Responses to IPUC Data Requests 1-21.
Provided on the enclosed CD are Attchments IPUC 4 -(1-2), 7a-(1-4), 13, 16, and 19,
If you have any questions, please feel free to call me at [phone].
Sincerely,
Tei UJet//c
Ted Weston,
Manager, Reguation
Enclosures
P AC- E-08-03/Rocky Mountain Power
September 10, 2008
¡PUC Data Request 1
IPUC Data Request 1
The Company indicated in Utah DPU Request 1.31 that an update for the project
costs is due on the last week of August. Please provide the most recent update (if
available) for the Company's estimated cost of the project.
Response to IPUC Data Request 1
Negotiations are continuing with potential contractors for the construction of the
345 kV transmission line. It was anticipated they would be complete by the end
of August 2008, however, additional discussions surrounding commodity pricing,
foundation costs based on soil conditions, right of way acquisition costs and
contractual risks are stil taking place. Final bids are expected to be completed by
mid-September 2008 and PacifiCorp management wil assess project costs and
determine 'next steps' by the end of September 2008. The information provided
in Utah DPU Request 1.31 remains the best project estimate at this time subject to
negotiated price movements for the above items. IPUC was previously provided
a copy of the Company's responses to Utah DPU Data Requests in Docket No.
08-035-42 in Utah. When provided in Utah, Attachment DPU 1.31 was
inadvertently not designated confidential; because it contains commercially-
sensitive line item detail for major components of the project, it should have been
designated confidentiaL. The Company will provide ¡PUC Staff a new copy of
Confidential Attachment DPU 1.31 upon receipt of a signed protective agreement
in this proceeding.
Responder: Wiliam A. Cuningham
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
¡PUC Data Request 2
IPUC Data Request 2
What is the curent $/mile cost for building a new 345kV transmission line?
Response to IPUC Data Request 2
Based on the project update provided in the Company's response to Utah DPU
Data Request 1.31 (specifically Attchment DPU 1.31), the $/mile cost for
building the new 345 kV transmission line would be approximately $4 milion per
mile. This isolates only the transmission line costs exclusive of substation,
communication and microwave sites. The estimated $/mile cost wil change after
project cost estimates are complete in September 2008.
Please note, that as explained in the Company's response to IPUC Data Request
1, Attachment DPU 1.31 in Utah Docket No. 08-035-42 is now designated
confidentiaL.
Responder: Willam A. Cunningham
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 3
IPUC Data Request 3
What is the total length, in miles, of the new transmission line that needs to be
built? What is the total length in Idaho? What is the total length in Utah?
Response to IPUC Data Request 3
The total length of the Populus to Terminal transmission line is 131.9 miles; 100.9
miles in Utah and 31.0 miles in Idaho.
Responder: Todd R. Jensen
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 4
IPUC Data Request 4
On a better resolution map, please identify all alternative transmission routes
considered and highlight the final route selected.
Response to IPUC Data Request 4
Please refer to Attachments IPUC 4 -1 and IPUC 4 -2. On these maps, the green
line indicates the Company's curent selected route. The black hatch marks
indicate alternative routes considered. In addition, Attachment IPUC 4 -1 depicts
the routes through Utah and Idaho, and Attchment IPUC 4 -2 depicts the routes
through Idaho in high resolution.
Responder: Lisa M. Symonds
IDAHO
PAC-E-08-03
ROCKY MOUNTAIN POWER
IPUC DATA REQUEST (1-21)
ATTACHMENT IPUC 4 -(1-2)
IDAHO
PAC-E-08-03
ROCKY MOUNTAIN POWER
IPUC DATA REQUEST (1-21)
ATTACHMENT IPUC 4 -(1-2)
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P AC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 5
IPUC Data Request 5
For each alternative route including the final route selected, please provide all
costs associated to build the transmission line on that paricular route.
Response to IPUC Data Request 5
Over 450 alternative route miles were considered, as defined by the route maps
provided as attachments to the Company's response to IPUC Data Request 4.
Detailed cost estimates were not completed for every route considered. The siting
criteria used to analyze the routes, including line mile costs, were applied to each
alternative route and segments were eliminated if they did not best meet the siting
criteria. The final alternatives selected between Populus and Ben Lomond varied
in mileage between 84 miles to over 90 miles. The final route selected is
approximately 86 miles in length, was the second shortest route, and best met all
the siting criteria. The costs for the alternative route miles would vary depending
on terrain andconstructability issues, but would be approximately $4 milion per
mile.
Responder: Lisa M. Symonds
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 6
IPUC Data Request 6
In regards to the new Populus Substation that needs to be built, please provide in
detail:
a. Why is it necessary to build this substation instead of utilzing or upgrading
nearby substations for this project?
b. What other locations did the Company consider to build this substation and
why were they not chosen?
c. Why did the Company choose to build the substation at this location?
Response to IPUC Data Request 6
a. PacifiCorp does not own any nearby substations suitable for this purpose.
b. Please refer to the Company's response to IPUC Data Request 4;
specifically Attachment IPUC 4 -1 which shows, in blue hatch marks, the
full Populus siting areas considered. The Populus substation site is located
such that three existing 345 kV lines wil loop in and out of the station at a
location where the lines are adjacent to each other, and where a south
bound corridor can reasonably originate for the new 345 kV lines. While
other locations east and west of this paricular site are possible and were
considered, it is believed that this general location results in the least
overall project cost, the highest practical reliabilty improvement, and the
lowest public impact. The availability of property, site access, and
environmental impact were also considered. This location also meets
PacifiCorp's long term transmission plans to interconnect future Gateway
West 500 kV line. This location wil eliminate the requirement for a
completely new station in the future and reduces the overall number of
stations required.
c. Please refer to the Company's response to subpar b above.
Responder: Wiliam A. CunninghamDavid E. Hagen
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 7
IPUC Data Request 7
Please provide any relevant analysis available that shows:
a. The current transfer capacities on Path C without this project and explain how
it is used to serve the load in Idaho.
b. The new transfer capacities on Path C with this project and explain how it wil
help serve the increased load and demand in Idaho.
Response to IPUC Data Request 7
a. The curent Path C capacity is 750 MW 'firm' north to south, and a range
from 350 MW to 950 MW south to north depending on temperature and the
amount of southeast Idaho load in any given hour.
North to South: In this direction, curent transmission capacity is used to
provide service for southbound point-to-point customers and for network
customer loads in Utah.
PacifiCorp provides service to up to 600 MW of load north of Path C net of
local generation. Service to this load is provided through PacifiCorp owned
lines and by contract through transmission lines owned by Idaho Power
Company. The current capacity of Path C is limited in both directions and
additional capacity is needed to provide new capacity to service growing loads
in southeast Idaho from generating resources south of Path C.
Please refer to Attachment IPUC 7a -1, which provides the Western Energy
Coordinating Council's (WECC) path rating catalog. Path C is a rated path
and can be found in the WECC path rating catalog, page Item 1-54. The
WECC path rating stated in the 2005 catalog is stil valid and applicable.
In addition to the above, path OTC limits are imposed on this "approved path
rating" based on operational and system conditions, which are seasonaL.
Please refer to Attachment IPUC 7a -2 through IPUC 7a -4, which provide
OTC studies recently submitted to WECC subcommittees for review and
approval.
b. The addition of the Populus-Terminal Project wil redefine Path C and, in
effect, increase the southbound capacity to 1,600 MW, and the northbound
capacity to 1,250 MW. The increase in capacity wil allow additional use of
generating resources south of Path C to serve Goshen area load.
Responder: Wiliam A. Cunningham IDavid E. Hagen
IDAHO
PAC-E-08-03
ROCKY MOUNTAIN POWER
IPUC DATA REQUEST (1-21)
ATTACHMENT IPUC 7a -(1-4)
P AC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 8
IPUC Data Request 8
Please explain how this project improves the service and reliability in the
Company's Idaho service territory.
Response to IPUC Data Request 8
This project wil enhance the overall reliabilty of portions of the transmission
grid connecting South East Idaho to Uta and to Wyoming. The project also
provides significant reliability benefits to the only existing high use commercial
transmission path that exists between Idaho and Utah. Reinforcement of this path
provides added capacity and an improved level of redundancy and reliability of
supply to South East Idaho from generation sources in Utah and Wyoming.
Significant impacts have occured on this interconnected path that can cause
disruptions and quality of service impacts to Idaho customers. Outages on
portions of this path have occured as stated in the Company's response to IPUC
Data Request 9.
This new line wil position PacifiCorp to serve long-term load growth needs,
improve overall system reliability by providing additional capacity to serve loads
under normal and contingency situations, leverage opportunities for additional
energy sales to other potential customers when demands are down in Idaho, and
provide PacifiCorp with greater flexibilty and the opportunity to consider options
regarding generation capacity additions to serve Idaho loads. The project provides
improved ability for delivery of renewable energy from existing and future wind
projects into South East Idaho.
Responder: Willam A. Cunningham
P AC-E-08-03/Rocky Mountain Power
September 10,2008
IPUC Data Request 9
IPUC Data Request 9
Identify the location of outages caused by transmission failure in Path C.
a. How wil this project prevent or mitigate similar outages and how will it
improve recovery from that condition in those areas affected by this project as
indicated in line 5 page 2 of Mr. Cupparo's testimony (provide supporting
metrics and any relevant analysis as needed)?
Response to IPUC Data Request 9
On the current transmission system between Wasatch Front and Idaho, there have
been three outages in the latter part of 2007 with a direct impact on the
transmission corridor that resulted in curailments of schedules, curilments of
interrptible loads and generation curailments in order to decrease loading across
the transmission corridor and the Bridger West transmission path. The
disturbances occured on September 27,2007, October 15,2007 and October 21,
2007, during periods of heavy flow northbound on the transmission corridor. As
a result, 1,454 customers were affected by the first outage and Nucor and
Monsanto loads were either interrpted and/or reduced during all three outages.
Generation curailments and realignments between 300 MW and 1,000 MW were
required in all three incidents.
On November 27,2007 and November 30, 2007, transmission faults occured on
the Terminal-Ben Lomond 345 kV line which is adjacent to the curent
transmission line. Both incidents caused another adjacent 345 kV line, Terminal-
Syracuse, to also trip and the result overloaded a 230/138 kV transformer which
relayed out of service. PacifiCorp Grid Operations had to respond by redirecting
energy flows, cut delivery schedules, and curail generation levels between 429
MWand 509 MW respectively for each incident. No retail customers were
impacted; however Sierra Pacific Power Company (SPP), Nevada Power
Company (NEVP) and Los Angeles Deparment of Water and Power (LADWP)
observed heavy flows across their transmission systems and had to implement
reactive procedures.
The abilty to recover from system disturbances was severely limited because
there was a lack of existing transmission capacity during these outages.
Construction of the Populus-to-Terminal 345 kV transmission line project wil
provide additional transmission capacity and redundancy to mitigate system
impacts due to unplanned outages.
Responder: Wiliam A. Cuningham
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 10
IPUC Data Request 10
Please provide comparison demonstrating why it is necessary to pursue this
project rather than upgrading the existing transmission corridors to increase
transfer capacity to handle the load growth?
Response to IPUC Data Request 10
Three alternatives were evaluated before choosing construction of the Populus-to-
Terminal 345 kV transmission line:
Alternative 1 ~ Rebuild the existing 138 kV transmission line from the
Treasureton Substation in Idaho to the Syracuse Substation in Utah. This
alternative limits the Path C capacity increase to a 300 MW north to south transfer
with little increased transfer capacity from south to north. It does not provide a
redundant path between Energy Gateway West and Energy Gateway South or
offer any additional capacity for the future. This alternative also does not tae
advantage of maximizing the existing Ben Lomond-Terminal corridor in order to
provide additional capacity between Idaho and Utah. This option failed to
provide adequate service in the northbound direction as required for two network
customers. One network customer will need up to 80 MW of new northbound
transmission capacity to serve loads by 2017. Additional northbound capacity
provides PacifiCorp Merchant with resource dispatch options to better serve loads
located near Goshen Idaho.
Alternative 2 - Construct a new single circuit 345 kV transmission line from the
future Populus Substation near Downey, Idaho to the Ben Lomond Substation in
Utah. This alternative provides a greater capacity increase from Idaho to Ben
Lomond. The alternative included an upgrade of the existing 138 kV line between
Ben Lomond and Terminal required to realize a minimum increase in capacity of
300 MW from Ben Lomond to the Wasatch Front load center. This alternative
does not provide a redundant path between Energy Gateway West and Energy
Gateway South and fails to take advantage of maximizing the existing vacant Ben
Lomond- Terminal transmission corridor.
Alternative 3 - Upgrade other existing paths or seek additional transmission
corridors into Utah. This option was evaluated and not pursued due alternate
project costs projections and the complexity of permitting new transmission
corridors when compared to upgrading the existing corridor. This alternative did
not provide the operational and reliability benefits required between southeast
Idaho and Utah.
Responder: Wiliam A. Cunningham
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 11
IPUC Data Request 11
During the construction of the project, the 230kV transmission line between
Terminal and Ben Lomond wil be upgraded to 345kV. If this par of the line is
under construction, what complications wil this cause in the Company's service
territory and other adjacent areas? If so, please list the areas affected and any
outages that will occur.
Response to IPUC Data Request 11
PacifiCorp wil limit transfers across the system between Terminal substation and
Ben Lomond substation so as to ensure the electrical system continues to meet all
applicable Western Electricity Coordinating Council (WECC) and North
American Electric Reliabilty Corporation (NERC) planing and operating
stadards. Whenever possible the Company will schedule work on those portions
of the system during low demand, lower risk periods. Service to load is not
expected to be significantly affected; however generation adjustments and some
limitations onthe interconnected system in the area may be required until the new
345 kV circuits are placed into service.
Responder: Wiliam A. Cuningham !David E. Hagen
P AC-E..08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 12
IPUC Data Request 12
Provide analysis demonstrating that this project does not diminish curent
reliability and how does this project improve reliability of the system as a whole
in the Idaho area. Please include any simulations, model, studies, etc. the
Company conducted.
Response to IPUC Data Request 12
The Company is proceeding in accordance with the Western Electricity
Coordinating Council (WECC) 1 North American Electric Reliabilty Corporation
(NERC) transmission system planing standards and requirements in addition to
the WECC path rating process. This process insures that significant transmission
additions, like this project in Idaho, do not diminish the reliabilty of the system in
Idaho and the overall, wider grid. The Phase 2 Study Report is being prepared for
submission to the WECC members for the project. This study evaluated several
WECC base case scenarios against numerous disturbances and outages to
determine the project's impact on reliability. As par of the Phase 2 Study Report,
both southbound and northbound dynamic analysis was performed assuming post-
construction MW ratings and produced no NERC 1 WECC standards violations.
The report also indicated increased path capacity and improved reliabilty
resulting from the completed project.
Responder: Wiliam A. Cuningham /David E. Hagen
P AC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 13
IPUC Data Request 13
Please explain and provide supporting information explaining why this
transmission line is necessary to relieve constraints in the system according to the
Western Governor's Association.
a. How does this transmission line help with congestion in the system (provide
analysis, documents, etc. as needed)?
Response to IPUC Data Request 13
Please refer to Attachment IPUC 13, which provides a copy of the "Conceptual
Plans for Electricity Transmission in the West - Report to the Western Governors'
Association" dated August 2001.
The transmission path between southeast Idaho and Wasatch Front (Path C) was
identified in the attached report as one of the highest constrained transmission
paths in the western interconnected system. The Transmission Working Group
considered a number of factors such as historical performance, capabilty that
must be set aside for reliability and system performance during outages or during
other-than-average conditions, load growth, and new generation resources.
Responder: Willam A. Cunningham IShayleah J. LaB ray
IDAHO
PAC-E-08-03
ROCKY MOUNTAIN POWER
IPUC DATA REQUEST (1-21)
ATTACHMENT IPUC 13
P AC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 14
IPUC Data Request 14
What kind of equipment/new technologies is the Company utilzing for this
project to improve power transfer efficiency?
Response to IPUC Data Request 14
For a portion of the project, the Company is using Aluminum Composite Core
Conductor (ACCC) conductor as compared to the Company's standard Aluminum
Conductor Steel Reinforced (ACSR) conductor. ACCC has the composite core
with trapezoidal shaped aluminum wires providing more current carrying
conductive aluminum and less weight as compared to the ACSR conductor with
the steel core.
The Companyis adding two series capacitors at Populus Substation to increase
power flows on the Jim Bridger 345 kV system. The series capacitors wil be
designed and built using the latest and newest technology.
Responder: Paul F. Capell
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 15
IPUC Data Request 15
How wil this project utilze energy from Goshen Wind Farm? How much of the
maximum transfer capacity of the new transmission line is allocated to renewable
resources?
Response to IPUC Data Request 15
This project provides increased capability to move Goshen wind energy between
Idaho and Utah. The posted network transmission (NT) allocation indicates 1,400
MW wil ultimately be available and all capacity has been assigned to NT use.
The new capacity will permit PacifiCorp's expanding renewable resource
portfolio to be moved to Idaho and Utah loads.
Responder: Kenneth T. Houston
P AC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 16
IPUC Data Request 16
Please provide any agreements with local wind farms or any other renewable
energy provider who wil utilize this line.
Response to IPUC Data Request 16
Please refer to Attachment IPUC 16. The line wil be used to move all network
resources, including those purchased, or owned, by PacifiCorp's Merchant
fuction, PacifiCorp Energy, which has a Network Integration Service
Agreement, and Uta Associated Municipal Power Systems (UAMPS) under the
Transmission Service and Operating Agreement. These network resources
include renewable resources.
Responder: Kenneth T. Houston
IDAHO
PAC-E-08-03
ROCKY MOUNTAIN POWER
IPUC DATA REQUEST (1-21)
ATTACHMENT IPUC 16
P AC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 17
IPUC Data Request 17
Per commitment #34 from the acquisition case (PAC-E-05-08), what are the
future considerations of planed generating capacity other than the energy from
renewable resources? Please provide details of planed additions and how these
additions wil help serve the increased load and demand in Idaho.
Response to IPUC Data Request 17
Please refer to PacifiCorp's Integrated Resource Plan (lRP) and Plan Updates,
which are both available to download on the Company's website at
ww.pacificorp.com (select "Energy Resources" then "Integrated Resource
Planing"). If downloading these documents is not practical, please contact the
Company for a hard copy of the documents.
In addition to renewable resources, the Company's plan shows the addition of
natural gas facilties, upgrades to existing thermal and hydro resources, combined
heat and power, demand side management and market purchases.Thes e
resources are intended to meet a planing reserve margin of 12 percent on top of
forecasted electricity demand for the system and individual load areas evaluated
for PacifiCorp's IRP.
Resource planing and cost allocations are performed on a system-wide basis.
Notwithstanding, please refer to pages 5-6 of the 2007 IRP Update for
expectations of future demand in Rocky Mountain Power's Idaho service
territory. The timing and size of planed generating plant additions in the IRP
take into account the expectations of future demand in Idaho.
Responder: Gregory N. Duvall
P AC- E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 18
IPUC Data Request 18
Has the Company obtain all the required land use permits from county or local
government in the State of Idaho for this project? Please explain.
Response to IPUC Data Request 18
The Company has obtained approval for the required county land use permit in
the State of Idaho. Bannock County approved a Zoning Clearance Permit on June
4,2008 for the Populus substation and 345 kV transmission line. No other local
or county land use permit approvals were required for the project from the
following entities: Oneida County, Malad City, and City of Downey.
Responder: Todd R. Jensen
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 19
IPUC Data Request 19
In paragraph 9 of the Company's application, the Company stated that the impact
of the project on Idaho's rate is estimated to be 3%. Although there will be no
determination of prudency, cost recovery or cost allocation in this case, please
give details on how the 3% amount was calculated.
Response to IPUC Data Request 19
Please refer to Attachment IPUC 19.
Responder: Steven R. McDougal
IDAHO
PAC-E-08-03
ROCKY MOUNTAIN POWER
IPUC DATA REQUEST (1-21)
ATTACHMENT IPUC 19
P AC-E-08-03/Rocky Mountain Power.
September 10, 2008
IPUC Data Request 20
IPUC Data Request 20
Please provide analysis demonstrating how this project relieves congestion in the
system.
Response to IPUc Data Request 20
PacifiCorp tracks curtailments of scheduled energy both northbound and
southbound on Path C. Schedules are established in one-hQur increments and
curtailments are identified by reason/explanation.
Curailments are monitored whenever scheduled energy transfers, either
northbound or southbound, were unable to be completed. The table below
summarizes the curailment data captured between May 2007 and April 2008
through PacifiCorp' s dispatch management system.
Path C Corridor Curtailments
Month Schedules Days of Days of Interruption Total number of
Interrupted Interruption During High Load MWh Interrupted
Hours(l)
January 2008 55 4 3 1,232
February 2008 5 2 1 226
March 2008 98 7 6 1,549
Apri12008 50 4 2 804
May 2007 0 0 0 0
June 2007 2 1 1 48
July 2007 0 0 0 0
August 2007 15 7 3 226
September 2007 145 9 5 5,789
October 2007 285 18 8 10,119
November 2007 247 16 10 5,641
December 2007 15 4 4 259
Total 917 72 43 25,893
(I) High load hours are defined as 6:00am to 1O:00pm Monday through Saturday.
The above char only reflects the number of schedule curailments. It does not
include the number of instances where the transmission corridor was unavailable
for scheduling. Construction of the Populus-to-Termina1345-kV Transmission
Line project wil add significant capacity to Path C, thus relieving congestion.
Responder: Wiliam A. Cuningham
PAC-E-08-03/Rocky Mountain Power
September 10, 2008
IPUC Data Request 21
IPUC Data Request 21
Please provide supporting information explaining the immediate reliabilty impact
and meet the increased load and demand.
Response to IPUc Data Request 21
Please refer to the Company's response to IPUC Data Request 11. Once the new
345 kV lines are placed into service, transfer capability to serve load and for
economic transfers wil substatially increase, and the overall reliability of the
system will be markedly improved.
Please refer to the Company's response to IPUC Data Request 12. Details of the
reliability impact are part of the Phase 2 Study Report cited in this response.
Responder: Wiliam A. Cuningham IDavid E. Hagen