20170303IPC to Tidwell Attachment 26.pdf

LARRY D.RIPLEY
PATRICK A.HARRINGTON
Idaho Power Company
P.0.Box 70
Boise,Idaho 83707
[phone]
Attorneys for Idaho Power Company
Street Address for Express Mail:
1221 West Idaho Street
Boise,Idaho 83702
FAX Telephone No.:[phone]
BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
IN THE MATTER OF THE APPLICATION )
OF IDAHO POWER COMPANY FOR AN )
AMENDMENT TO CERTIFICATE OF
PUBLIC CONVENIENCE AND NECESSITY,)
CERTIFICATE NO.272
CASE NO.IPC-E-95-6
)APPLICATION FOR AN AMEND
MENT TO CERTIFICATE OF
PUBLIC CONVENIENCE AND
NECESSITY NO.272
)
On October 31,1973,Idaho Power filed an application with the Commission
(which was designated Case No.U-1 006-89)requesting a Certificate of Public
Convenience and Necessity for the construction and installation of a 50 megawatt (MW)
combustion turbine generator and related facilities at the Company's Wood River
Substation near Hailey,Idaho,and the conversion and rebuild of the 46 kV transmission
and distribution lines from the Wood River Substation to the Ketchum Substation to a
138 kV transmission line.The Commission approved the Company's application in its
APPLICATION FOR AN AMENDMENT TO CERTIFICATE,Page 1
Order No.1 1315 and issued Certificate of Public Convenience and Necessity No.272 (see
(
Exhibit 1).The Company is hereby requesting an amendment to Certificate No.272
relating to the proposed Wood River Ketchum 138 kV transmission line that was approved
therein.
The Company's primary concern in its 1973 application (Case No.U-1006-
89)was to provide back-up facilities for the two transmission lines which extended service
to the Company's two substations in Hailey.At that time,Idaho Power provided service
to Hailey through a 46 kV line from the Shoshone Substation to the Hailey Substation,and
through a 138 kV line from the King Substation near Hagerman to the Wood River
Substation near Hailey.The 46 kV Shoshone-Hailey line had insufficient capacity to serve
the entire load in the area,and an outage on the 138 kV King-Wood River line (which is
(72 miles long and,as described in Order No.11315,"traverses high desert and
mountainous terrain,subject to storms,snow,avalanches,slides,fire and icing conditions")
would affect the entire Hailey-Ketchum-Sun Valley area.Accordingly,pursuant to the
Commission's authorization in Order No.11315 and Certificate No.272,the Company
built and installed the combustion turbine generator (the Hailey Turbine)at the Wood River
Substation.The Hailey Turbine made back-up service available in the event of an outage
on the King-Wood River line.In 1989,Idaho Power completed construction of a new
138 kV transmission line extending from the Midpoint Substation to the Silver Substation
to the Hailey Substation.This line completed the Company's capacity and reliability
upgrade of electric service to Hailey,and allowed the Company to eventually dispose of
APPLICATION FOR AN AMENDMENT TO CERTIFICATE,Page 2
the Hailey Turbine,as approved by the Commission's Order No.24676 in Case No.IPC-E-
92-9 dated January 27,1993 (see Exhibit 2).
Idaho Power's application in Case No.U-1 006-89 also addressed the
Company's request for authority to construct electric facilities extending north of Hailey to
serve the Ketchum-Sun Valley area.The Company proposed a new 138 kV transmission
line from the Wood River Substation to the Ketchum Substation to provide back-up service
for the existing Wood River-Ketchum 138 kV transmission line which runs along the east
end of the Wood River Valley.However,after the issuance of the Commission's Order No.
11315 and Certificate No.272,Idaho Power was unable to obtain the necessary right-of-
way for the additional 138 kV Wood River-Ketchum transmission line.The proposed new
138 kV line was intended to follow a portion of an existing 46 kV line route from the Wood
River Substation to the Gimlet area,but also required right-of-way through the city of
Ketchum.In the meantime,the Company began the difficult and protracted process of
obtaining the necessary easements,licenses and permits for its Midpoint-Silver-Hailey
transmission line referenced above.Faced with continuing right-of-way obstacles in
extending a new 138 kV line north of Hailey,the Company has continued to rely upon its
existing Wood River-Ketchum 138 kV line for service to the Ketchum-Sun Valley area.
Idaho Power recently performed an extensive reassessment of the feasibility
and need for an additional 138 kV transmission line from the Wood River Substation to the
Ketchum Substation.This study included a review of both the capacity requirements and
the reliability requirements for Idaho Power's electric service to the Ketchum-Sun Valley
area.
APPLICATION FOR AN AMENDMENT TO CERTIFICATE,Page 3
Idaho Power's current projections of electric demand in the Ketchum-Sun
(
Valley area indicate that the existing Wood River-Ketchum 138 kV transmission line has
sufficient capacity to meet the area's electric needs for the foreseeable future.The 138 kV
line's capacity ranges from approximately 120-130 MW in the winter to approximately 90
MW during the summer (power lines are able to carry more electricity in colder conditions).
By comparison,the actual winter peak load on the transmission line was 55.5 MW for
1994-1995,and projected winter peak loads are estimated at 73 MW for 2005-2006 and
110 MW for 2030-2035.Summer peak loads on the transmission line are projected to stay
well below the 90 MW capacity of the line over the same planning period.Idaho Power will
continue to monitor its load growth projections and make modifications where necessary.
However,based on current projections,there is presently no need for a new 138 kV
(transmission line to provide additional electrical capacity to the Ketchum-Sun Valley area.
Idaho Power has also thoroughly reviewed the reliability of its electrical
service to the Ketchum-Sun Valley area.The Wood River-Ketchum 138 kV transmission
line has had an excellent record of reliability since its construction in 1962.Nonetheless,
the Company has taken a number of steps to further improve the reliability of the line
including the following:
1.Structural Assessment -Energy Data Management,Inc.of Colorado
has performed a field inspection and structural analysis of the poles,cross-arms,
insulators,conductors and other components of the transmission line.This study
confirmed that the transmission line structures are in good condition and are in
APPLICATION FOR AN AMENDMENT TO CERTIFICATE,Page 4
conformance with applicable National Electrical Safety Code standards.Structures and
cross-arms identified in the study as needing work were repaired.
Electrical Assessment -Energy Data Management and Power2.
Engineers of Hailey have analyzed the historical performance of the transmission line,
including outages and lightning-related incidents.The transmission line was determined
to have an excellent outage history,with only two unplanned outages in the past fourteen
years,for a total duration of only three minutes.The electrical assessment was based
upon Idaho Power's records and did not include any brief outages which may not have
been recorded for the line over the years.
Fire Protection -Osmose,Inc.of New York has coated the3.
transmission poles with Fire-Guard protectant,which is designed to protect the poles
through three fires.
4.Avalanche Study -Power Engineers and Energy Data Management
have reviewed the probabilities and severities of avalanches in the vicinity of the
transmission line and calculated the resulting pole strength requirements.All structures
were determined to have adequate strength to withstand a 50-year recurrence avalanche.
5.Conductor Assessment -Idaho Power performed visual inspections
of several spans of the transmission line wires which were removed in connection with the
rerouting of a one-mile segment of the line in 1994.
6.Maintenance Plan -Idaho Power has developed an enhanced
maintenance plan to repair and replace power line components as needed.
APPLICATION FOR AN AMENDMENT TO CERTIFICATE,Page 5
Emergency Action Plan -Idaho Power has prepared a detailed7.
(
comprehensive emergency action plan to facilitate a rapid and effective response to a
service outage or other emergency regarding the power line.The plan includes detailed
maps and directions for access to structures,specific guidelines for structure
replacements,and contact lists for internal and external communications (e.g.law
enforcement,hospitals,etc.).Materials are stored in Hailey to facilitate the rapid
restoration of service in the event of an unplanned line outage.
Idaho Power has also recently completed an extensive public participation
process regarding the possible construction of a second 1 38 kV transmission line from the
Wood River Substation to the Ketchum Substation.The Company's process included
meetings before the Ketchum and Sun Valley City Councils,as well as before the Blaine
(County Board of Commissioners.Idaho Power also presented a proposal to construct the
new transmission line to a Community Advisory Committee whose members are listed on
the Committee list attached hereto as Exhibit 3.In addition,Idaho Power held a public
open house at Ketchum City Hall (with invitations sent to over 8,000 Idaho Power
customers in northern Blaine County)to provide information regarding the proposed
transmission line and to receive public comments.
At the conclusion of Idaho Power's public participation process,the Company
carefully evaluated the input received from the area's public officials and citizens.The
overwhelming response from the parties commenting was that,despite the unavoidable
risk of an outage to the existing transmission line,the proposed transmission line should
not be built.The reasons for public opposition to the line included the difficulty of finding
(
APPLICATION FOR AN AMENDMENT TO CERTIFICATE,Page 6
an acceptable route for the transmission line,aesthetic impacts,health and safety
concerns,and excessive cost of burying part or all of the line.(The newspaper articles
attached as Exhibit 4 provide additional information regarding public input on the line).
Based on Idaho Power's extensive review of the proposal to construct a
138 kV transmission line from the Wood River Substation to the Ketchum Substation,and
in light of the public comments received regarding the line,the Company has concluded
that the project is not feasible at this time.Idaho Power will continue to monitor the
condition of the existing Wood River-Ketchum transmission line,the increase in load
growth in the Ketchum-Sun Valley area,and the feasibility of obtaining the required right-
of-way and public permits for a second 138 kV line.
Communications with reference to this Application should be sent to the
following:
Larry D.Ripley
Attorney
Idaho Power Company
P.O.Box 70
Boise,Idaho 83707
Patrick A.Harrington
Attorney
Idaho Power Company
P.O.Box 70
Boise,Idaho 83707
WHEREFORE,the Company requests an Amendment to Certificate of
Public Convenience and Necessity,Certificate No.272,to remove the authority for the
construction of a second Wood River-Ketchum 138 kV transmission line from Certificate
of Public Convenience and Necessity,Certificate No.272,as authorized by the
Commission in U-1 006-89,Order No.11315.
APPLICATION FOR AN AMENDMENT TO CERTIFICATE,Page 7