20260206Reply Comments - Redacted.pdf

-NIQAW POWER,
RECEIVED
DONOVAN WALKER FEBRUARY 6, 2026
Lead Counsel IDAHO PUBLIC
dwalker(a)idahopower.com UTILITIES COMMISSION
February 6, 2026
VIA ELECTRONIC FILING
Commission Secretary
Idaho Public Utilities Commission
11331 W. Chinden Blvd., Bldg 8,
Suite 201-A (83714)
PO Box 83720
Boise, Idaho 83720-0074
Re: Case No. IPC-E-25-29
Application of Idaho Power Company's for a Certificate of Public
Convenience and Necessity for the Bennett Gas Expansion Project and for
an Associated Accounting Order
Dear Commission Secretary:
Attached for electronic filing is Idaho Power Company's ("Idaho Power") Reply
Comments in regard to the above matter.
The confidential version will be sent in a separate email to the parties who have
executed the Protective Agreement.
If you have any questions about the aforementioned documents, please do not
hesitate to contact me.
Very truly yours,
Donovan E. Walker
DEW:sg
Attachments
1221 W. Idaho St(83702)
P.O. Box 70
Boise, ID 83707

CERTIFICATE OF ATTORNEY
ASSERTION THAT INFORMATION CONTAINED IN AN IDAHO PUBLIC UTILITIES
COMMISSION FILING IS PROTECTED FROM PUBLIC INSPECTION
Application of Idaho Power Company for Approval of a Certificate of Public
Convenience and Necessity for the Bennett Gas Expansion Project and for an
Associated Accounting Order
Case No. IPC-E-25-29
The undersigned attorney, in accordance with Commission Rules of Procedure 67,
believes that Idaho Power Company's Reply Comments dated February 6, 2026, contain
information that Idaho Power Company and a third party claim is a confidential trade
secret, business records of a private enterprise required by law to be submitted or to be
inspected by a public agency, and/or public records exempt from disclosure by state or
federal law (material nonpublic information under U.S. Securities and Exchange
Commission Regulation FD) as described in Idaho Code § 74-101, et seq., and/or § 48-
801, et seq. As such, it is protected from public disclosure and exempt from public
inspection, examination, or copying.
DATED this 6t" day of February 2026.
Donovan Walker
Counsel for Idaho Power Company

DONOVAN E. WALKER (ISB No. 5921)
Idaho Power Company
1221 West Idaho Street (83702)
P.O. Box 70
Boise, Idaho 83707
Telephone: [phone]
Facsimile: [phone]
dwalker(o-)idahopower.com
Attorney for Idaho Power Company
BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
IN THE MATTER OF IDAHO POWER )
COMPANY'S APPLICATION FOR A ) CASE NO. IPC-E-25-29
CERTIFICATE OF PUBLIC CONVENIENCE )
AND NECESSITY FOR THE BENNETT GAS ) IDAHO POWER COMPANY'S
EXPANSION PROJECT AND FOR AN ) REPLY COMMENTS
ASSOCIATED ACCOUNTING ORDER. )
COMES NOW, Idaho Power Company ("Idaho Power" or "Company"), and,
pursuant to Idaho Public Utilities Commission's ("Commission") Rules of Procedure 201-
204 and the Notice of Modified Procedure, Order No. 36854, hereby respectfully submits
the following Reply Comments in response to Comments filed by Commission Staff
("Staff") and the Idaho Irrigation Pumpers Association, Inc. ("IIPA") on January 23, 2026.
IDAHO POWER COMPANY'S REPLY COMMENTS - 1

I. BACKGROUND
1. Idaho Power closely monitors resource needs and responds with
appropriate urgency to acquire additional low-cost, reliable sources of generation and
capacity, as evidenced by Idaho Power's consecutive requests to acquire resources to
be online in 2023,E 2024,2 2025,3 2026,4 2027,5 and 2028.6 In response to resource needs
identified in the 2023 Integrated Resource Plan ("IRP"), on August 16, 2024, Idaho Power
conducted a competitive solicitation through the issuance of an All-Source Request for
Proposal ("RFP') seeking to acquire a combination of energy and capacity resources
("2028 RFP"). The 2028 RFP did not restrict bids based on resource type or ownership
structure, however, Idaho Power outlined that the deficit required a minimum of
approximately 138 megawatts (WW") of incremental capacity needs and 555 MW of
supply-side resource additions in 2028 and beyond. The Company accepted energy or
capacity incremental to its system beginning in the summer 2028 timeframe and beyond,
from market energy purchases or new or existing resources.
2. The evaluation of the 2028 RFP bids was bifurcated, with prioritization of
the 2028 bids in order to meet summer demand in 2028, followed by evaluation of the
bids with a commercial operation date after April 1, 2028 ("Beyond April 2028 Bids").
Idaho Power's discussion in this case is specific to the evaluation of the Beyond April
2028 Bids for which the Company ultimately received approval of the final shortlist of bids
with a commercial operation date no later than June 1, 2029 ("2029 Bids") to meet the
Case Nos. IPC-E-22-06 and IPC-E-22-13.
2 Case Nos. IPC-E-23-05 and IPC-E-23-20.
3 Case Nos. IPC-E-22-29 and IPC-E-23-20.
4 Case Nos. IPC-24-01, IPC-E-24-16, and IPC-E-24-45.
5 Case Nos. IPC-E-24-42 and IPC-E-25-27.
6 Case No. IPC-E-25-29.
IDAHO POWER COMPANY'S REPLY COMMENTS -2

identified capacity deficits. The Public Utility Commission of Oregon ("OPUC") found that
Idaho Power conducted a fair and competitive resource acquisition procurement process
in accordance with the OPUC competitive bidding rules.' The Company used the results
from that approved final shortlist, selecting the most cost-effective project identified
through the extensive competitive bidding process, the Bennett Gas Expansion Project,
to help meet the identified 2028 capacity deficiency.
3. Idaho Power records the accumulation of all costs associated with the
construction of an asset, including the cost of financing the construction expenditures, or
Allowance for Funds Used During Construction ("AFUDC"), in Federal Energy Regulatory
Commission ("FERC") Account 107 — Construction Work in Progress ("CWIP"). When the
plant is completed and placed in service, the total cost of the plant, including AFUDC, is
moved to FERC Account 101 — Electric Plant-in-Service, placing the asset in rate base.
For generation resources, typically, once selected on the final shortlist having been
identified as a least-cost, least risk resource, and subsequently acknowledged by the
OPUC, Idaho Power moves the charges to FERC Account 107 - CWIP as the viability of
the project has been confirmed, and AFUDC commences.
4. Based on industry demand for long-lead materials, and to ensure
commercial operation dates are met, the Company has been incurring capital
expenditures associated with resource procurements prior to acknowledgement of the
final shortlist from the OPUC or granting of a Certificate of Public Convenience and
Necessity ("CPCN") from the Idaho Commission. For example, in order to secure a
position in the queue to purchase the reciprocating internal combustion engines ("recips")
OPUC Order No. 25-327, Docket UM 2317, Aug. 30, 2025.
IDAHO POWER COMPANY'S REPLY COMMENTS - 3

for the Bennett Gas Expansion Project, Idaho Power was required to make a down
payment prior to acknowledgement of the final shortlist by the OPUC or issuance of a
CPCN from the Idaho Commission. This down payment was necessary to ensure the
plant would be operational in time to meet the identified capacity need. Because Idaho
Power has not previously been in a position to incur costs associated with resource
procurements prior to receiving a CPCN, the Company is requesting the Commission
acknowledge it is appropriate to begin the accrual of AFUDC once the project has been
deemed viable and expenditures associated with the resource procurement have been
incurred.
5. On September 19, 2025, Idaho Power submitted an Application to the
Commission for an order: (1) granting a CPCN for the expansion of the existing Bennett
Mountain Power Plant to include the addition of the Bennett Gas Expansion Project, a
cost-effective natural gas-fueled facility providing up to 167 MW of generation to meet an
identified capacity deficit in 2028, (2) confirmation of the Company's application of accrual
of AFUDC for the Bennett Gas Expansion Project upon initial procurement activities for
the recips, and (3) approving the commencement of the accrual of AFUDC on capital
expenditures associated with future resource procurements at the time the project has
been deemed viable by the Company.
6. On January 23, 2026, Comments were filed by Staff and IIPA. In their
Comments, Staff recommends the Commission (1) issue a CPCN for the Bennett Gas
Expansion Project, (2) clarify that prudence of the final cost will be determined based on
actual costs when the Company seeks recovery in rates, and (3) approve AFUDC accrual
for the Bennett Gas Expansion Project but deny Idaho Power's request for blanket early
IDAHO POWER COMPANY'S REPLY COMMENTS -4

AFUDC accrual on future resource procurements.$ The IIPA however, in their Comments,
recommend the Commission deny or defer the issuance of a CPCN for the Bennett Gas
Expansion Project, suggesting the Company has not demonstrated a capacity need
attributable to existing customers.
7. In these Reply Comments, Idaho Power responds to the recommendations
offered by Staff and addresses IIPA's concerns regarding the capacity need
demonstration, the standard by which the Company is requesting the Commission issue
a CPCN for the Bennett Gas Expansion Project. The Company respectfully requests the
Commission (1) accept Staff's recommendations to issue a CPCN for the Bennett Gas
Expansion Project and approve AFUDC accrual for the Bennett Gas Expansion Project
upon initial procurement activities, (2) accept the Company's request to approve the
commencement of the accrual of AFUDC on capital expenditures associated with future
resource procurements at the time the project has been deemed viable by the Company,
and (3) reject IIPA's unwarranted proposal to deny or defer the issuance of a CPCN for
the Bennett Gas Expansion Project.
II. REPLY COMMENTS
A. The Commission should adopt Staff's recommendation to issue a CPCN for
the Bennett Gas Expansion Project and approve AFUDC accrual beginning
at initial procurement activities.
8. In order to comply with its continuing obligation to serve all customers
located in its certificated service territory, the Company must at times acquire additional
resources to meet the identified capacity deficits on its system when the need arises. On
February 29, 2024, Idaho Power commenced a competitive bidding process, filing a
8 Staff Comments, page 8.
IDAHO POWER COMPANY'S REPLY COMMENTS - 5

request with the OPUC to (1) approve the selection of London Economics International
LLC ("LEI") as the Independent Evaluator ("IE") for the 2028 RFP, (2) approve the
proposed 2028 RFP scoring and modeling methodology, (3) approve the draft 2028 RFP,
and (4) waive certain competitive bidding rules to allow for expedited review and approval
of the 2028 RFP. On April 30, 2024, the OPUC approved the selection of LEI as the IE
for Idaho Power's 2028 RFP and evaluation of 2028 RFP resources. The OPUC also
approved the concurrent review of both the scoring and modeling methodologies and
preparation of the draft 2028 RFP.
9. Idaho Power performed a quantitative and qualitative evaluation with an
objective scoring methodology to reasonably evaluate the price and non-price attributes
of the Beyond April 2028 Bids submitted through the RFP process, which included 83
proposals from 18 different bidders, with a total of 117 resource bids, ultimately identifying
the 2029 Bids final shortlist of projects with commercial operation by June 1, 2029. As
required under the OPUC competitive bidding rules, the final shortlist was submitted for
OPUC review and on August 19, 2025, the OPUC acknowledged the 2029 Bids final
shortlist. Following identification as the most cost-effective project necessary to meet the
identified 2029 capacity deficiency, the Internal Bid Team was provided a Notice to
Proceed with the Bennett Gas Expansion Project.
10. Idaho Power appreciates Staff's thorough review of the Company's request
in this case, their recommended issuance of a CPCN for the Bennett Gas Expansion
Project and approval of the accrual of AFUDC at the commencement of initial
procurement activities for the project. Staff performed a comprehensive analysis in this
proceeding confirming the requirement to solicit new resources, the selection process and
IDAHO POWER COMPANY'S REPLY COMMENTS - 6

the result of the evaluation, finding that the "Company has met the regulatory
requirements to obtain a CPCN."g Staff reviewed the Company's load and resource
assumptions utilized in the most recent system reliability assessment to produce Idaho
Power's annual capacity position, concluding the capacity deficit may be even larger than
the 265 MW identified by the Company because the results are based on nine additional
generation or transmission projects that are scheduled to be online in 2026 or 2027,
which, if even one project is delayed, would result in a larger capacity deficit.10
11. With respect to the selection process, Staff thoroughly reviewed the 2028
RFP and the IE closing report, noting that the fairness of the process is "foundational to
any of its results" and that they believe the "selection process was fair and reasonable."11
Staff agreed that the 2028 RFP allowed bids for all commercially viable resource types
and that Idaho Power appropriately bifurcated the bidders into two groups based on
commercial operation dates, concluding that there was "a sufficient number of bids in
each group to ensure adequate competition.1112 Further, Staff independently examined the
Company's Ievelized cost calculations, noting that the values are a major determinant in
which resources are selected, concluding that they were "fairly and reasonably
determined." Finally, Staff independently verified Idaho Power's determination of the top
performing bids through the stochastic analyses, noting that the Bennett Gas Expansion
Project is a least-cost resource based "on its top-tier outcome" and its "unique status as
the only dispatchable resource.'113
9 Staff Comments, page 3 and page 6.
10 Staff Comments, page 3.
11 Id., pages 3-4.
12 Id., page 4.
13 Id.
IDAHO POWER COMPANY'S REPLY COMMENTS - 7

12. In addition to their review of the 2028 RFP evaluation and selection process,
and confirmation that identification of the Bennett Gas Expansion Project is a least-cost
resource, Staff evaluated the risk associated with the project concluding the Bennett Gas
Expansion Project is a least-risk resource for a number of reasons, including "(1) the
anticipated reduction of the overall capacity deficit, (2) the expedited timeframe for the
[p]roject to be brought online, (3) lack of fuel-supply risk, and (4) lack of permitting risk.1114
In addition to aiding in the reduction of the capacity deficit, Staff noted that, because the
Bennett Gas Expansion Project can be brought online quicker than other bids on the 2029
Bids final shortlist, it can further reduce system reliability risk. Staff also highlighted that
the Company has reduced the fuel-supply risk by procuring additional natural gas supply
capacity and securing the applications for the Conditional Use Permit for construction and
the Air Permit — Permit to Construct and the Bureau of Land Management easement
permit were timely submitted. Staff agrees that the Bennett Gas Expansion Project is the
least-cost, least-risk resource when compared to other viable resources.15
B. The Company has demonstrated incremental capacity needs and has an
obligation to serve all those that request it within its service area.
13. To comply with its continuing obligations to serve customers, Idaho Power
must acquire additional resources to meet the identified capacity deficits on its system
when the need arises. While Staff agrees that the Company "faces a capacity deficit in
2028 and therefore, additional resources are necessary to ensure system reliability,""
IIPA does not believe the Company has met the "standard of necessity"17 because it
14 Id., page 5.
15 Id., page 2.
16 Id., page 3.
17 IIPA Comments, page 1.
IDAHO POWER COMPANY'S REPLY COMMENTS - 8

claims Idaho Power did not demonstrate the capacity need is attributable to only what
IIPA characterizes as "existing"18 customers. IIPA's conclusion, however, is based on a
misrepresentation of Idaho Power's obligations under Idaho Code as well as a
misunderstanding of the capacity need determination performed as part of the system
reliability assessment.
14. As noted by IIPA, Idaho Power does not dispute that large loads are
contributing to the capacity need.19 The standard by which the Company is requesting a
CPCN for the Bennett Gas Expansion Project is that "the present or future public
convenience and necessity require or will require such construction"20 which is supported
by the 265 MW capacity deficiency presented in this case. Further, under Idaho Code §§
61-302, 61-315, 61-507, the Company has an obligation to provide adequate, efficient,
just, and reasonable service on a nondiscriminatory basis to all those that request it within
its service area. This obligation to serve does not apply to only "existing" customers nor
should the capacity need determination be based only on the loads of "existing"
customers, as suggested by IIPA.21 Rather, Idaho Code § 61-315 prohibits the
discrimination or preference of rates, charges, service, or facilities between classes of
service. Whether it is for all the Company's customers, or for a class of one customer,
Idaho Power's obligation to provide adequate, efficient, just, and reasonable service is
18 While IIPA uses the term "existing customers" repeatedly throughout its Comments as the purported
benchmark for necessity, it provides no definition of that term, no citation to statute or Commission
precedent adopting it, and no explanation of how or when a customer transitions into or out of the
"existing" category.
19 Id., page 3.
20 Idaho Code § 61-526.
21 IIPA Comments, page 1.
IDAHO POWER COMPANY'S REPLY COMMENTS - 9

the same. Contrary to IIPA's assertion, a resource can be said to serve a public necessity
even though the capacity need is not attributable solely to existing customers.22
15. The Company's capacity planning process must align with its statutory
obligation to provide nondiscriminatory service under Idaho Code §§ 61-302, 61-315, and
61-507. Because Idaho Power must plan to reliably serve all obligated firm loads, these
loads are necessarily included as an input when performing system reliability
assessments. Excluding obligated loads from the system reliability evaluation would
result in an artificially reduced capacity requirement and would be inconsistent with the
Company's duty to ensure adequate resources for all customers it is required to serve.
16. Idaho Power operates an integrated system and the inclusion of the large
loads in the determination of capacity needs is not only appropriate, but is necessary to
ensure the Company can continue to provide safe, reliable electric service in 2028 to all
customers in its service area. As noted by IIPA, the load forecast utilized to evaluate the
system capacity included a new large load customer whose loads are contributing to
projected peak loads in 2028. However, IIPA failed to consider that the new large load
customer referenced has an executed energy service agreement with Idaho Power and
therefore the Company has an obligation to serve that customer. Idaho Power cannot
simply remove the new loads from the determination of capacity needs as the omission
would result in the Company being unable to meet system reliability requirements.
i. Idaho Power's clarification of the capacity need determination.
17. To support their claim that the capacity need should be based on loads of
only existing customers, in their Comments, IIPA explains their attempt to recalculate the
22 Id., page 1.
IDAHO POWER COMPANY'S REPLY COMMENTS - 10

capacity deficiency. However, IIPA's calculation includes some errors worthy of
clarification. First, IIPA removes loads associated with a specific new large customer but
uses a capacity number for this customer from their construction agreement, rather than
the loads for which the projected system peak was based. The construction agreement
reflects loads for the customer once the facility is fully operational, which is not expected
to occur until at least 2029. The projected 2028 system peak for which the capacity need
was based, includes loads associated with this customer of less than those reflected in
the construction agreement. Contrary to IIPA's assertion that this value was
"undisclosed",23 it was provided to IIPA as a discovery response.24
18. Further, IIPA presents what it characterizes as a "key example" to illustrate
the risk proposed by speculative load growth. However, IIPA incorrectly misrepresents
that "Idaho Power's filings and utility planning treat this proposed load as potential future
firm demand".25 IIPA goes on to suggest the proposed Diode Ventures technology park—
with anticipated loads between 600-800 MW — was "folded into forecasts of system
need"26 yet Diode Ventures load was not included in the projected 2028 system peak
need presented in this case. Accordingly, the Commission should disregard IIPA's
assertions that approval of the Bennett Gas Expansion Project would improperly expose
customers to risk based on speculative load growth, including its contentions regarding
potential non-materialization of Diode Ventures' uncontracted 600-800 MW, because
those arguments are unsupported by the record and rest on a fundamental
mischaracterization of the capacity need demonstrated in this case.
23 IIPA Comments, page 6.
24 See the Company's Response to IIPA Request No. 1-2(d)—Confidential Attachment.
25 Id., page 7.
26 Id., pages 6-7.
IDAHO POWER COMPANY'S REPLY COMMENTS - 11

19. In addition to a misunderstanding of the new large loads included in the
projected system peak utilized in system reliability assessment, the methodology IIPA
assumed to recalculate the capacity deficiency was flawed. While removing loads from
the projected system peak can be performed with "simple arithmetic,1127 the resulting
impact to the annual capacity position determination cannot. Rather, as detailed in the
Direct Testimony of Mr. Jared Ellsworth, the Company calculates the capacity position to
meet the pre-determined Loss of Load Expectation ("LOLE") threshold, which is derived
from the hourly Loss of Load Probability, also known as the high-risk hours of the year.
The computation of the capacity position is far more complex than the subtraction of peak
load from resource capacity.
C. Deferral of the Bennett Gas Expansion Project would exacerbate the
Company's 2028 resource needs and jeopardize reliability.
20. In their Comments, IIPA is critical of Idaho Power's urgency to address the
near-term 2028 capacity deficits, suggesting it is "[s]elf-created, [a]ssumption-[d]riven and
[r]eversible,"21 and that deferring the Bennett Gas Expansion Project would be
appropriate. The Company agrees that the near-term capacity deficit is based on planning
assumptions that can change, after all assumptions are fundamental to resource
planning, and during the near-term resource decision-making phase, the annual capacity
positions can be very fluid. In the face of growing loads, Idaho Power closely monitors
resource needs and responds with added urgency. In addition to the nearly 18-month,
extensive, fair and competitive RFP process the Company was required to follow, contract
negotiation, contract execution, material procurement, and construction can add another
2' Id., page 4.
28 Id., page 8.
IDAHO POWER COMPANY'S REPLY COMMENTS - 12

two to six years to the time it takes to bring a resource online. As a result, the Company
performs system reliability assessments between planning periods using the most up-to-
date assumptions. The resulting annual capacity position is, in fact, based on a snapshot
in time, as suggested by IIPA;29 it is reflective of the Company's annual capacity position
at the time a resource is procured.
21. On the contrary, resource decisions based on a "single, stable reliability
trajectory"30 would fail to recognize resource adequacy changes between planning
periods, potentially impacting Idaho Power's ability to meet system reliability
requirements. Using the Jackalope Wind Project referenced by IIPA as an example,31
regardless of the fact that the Company had received a CPCN and approval of the Power
Purchase Agreement associated with the project, the Jackalope Wind Project was no
longer able to meet the 2027 commercial operation date and therefore no longer able to
contribute to Idaho Power's capacity needs. Had Idaho Power included the project in the
Company's resource portfolio, Idaho Power's annual capacity position would be
overstated and not reflective of its inability to meet system reliability requirements in 2027
and beyond. Removing the Jackalope Wind Project was prudent and identified a
remaining capacity need and the Company was able to procure an alternative resource
to help fill the remaining capacity deficiency.
22. The diversity of least-cost, least-risk resources included on the final shortlist
of 2029 Bids is also critical with fluid annual capacity positions. During evaluation of the
bids, as part of the qualitative review, the Company considered potential factors that could
29 Id.
30 Id.
31 Id.
IDAHO POWER COMPANY'S REPLY COMMENTS - 13

impact the commercial operation date including a repeal of the Inflation Reduction Act
("IRA"), import tariffs, siting factors, and generator interconnection/transmission factors,
prioritizing those with 2028 commercial operation dates due to carrying lower IRA repeal
risk based on the information known at the time.32 This diversity of resources proved
beneficial due to the repeal of the IRA and implementation of new or increased import
tariffs, as the Bennett Gas Expansion Project was a dispatchable resource and not
impacted by the IRA repeal.
23. IIPA was also disapproving of Idaho Power's decision to accelerate the
commercial operation date of the Bennett Gas Expansion Project from the originally bid
date of April 2029 to June 2028, suggesting the change was a "discretionary planning
decision" asserting that the Company did not present evidence that the system would be
unreliable absent the acceleration.33 IIPA's supposition is unfounded. In fact, Idaho Power
presented the results in Table 2 of the Direct Testimony of Mr. Jared Ellsworth and also
clarified in discovery.34 Idaho Power performed a sensitivity analysis assessing the impact
to the annual capacity position to meet the 0.1 event-days per year LOLE threshold with
and without the Bennett Gas Expansion Project; these results clearly identified the 2028
system reliability assessment worsens by over 100 MW without the Bennett Gas
Expansion Project. Deferral of the project would continue to grow the capacity deficiency.
24. IIPA's further criticism of the Company's lack of consideration for interim
alternatives such as short-term market purchase and demand-side measures is
unsupported. With respect to market purchases, Idaho Power continually evaluates their
sz See the Direct Testimony of Mr. Eric Hackett, pages 23-24.
ss Id., page 9.
sa See the Company's Response to IIPA's Request for Production No. 1-18.
IDAHO POWER COMPANY'S REPLY COMMENTS - 14

feasibility to meet capacity deficits in future periods, including 2028 and beyond. However,
to fill remaining capacity deficits, market purchases must provide incremental capacity to
the system — i.e., be imported on transmission that has not already been assumed to be
contributing to the system. The Company's IRP and RFP modeling assumes 600 MW of
Idaho Power's existing third-party transmission rights are importing wholesale market
energy purchases and contributing capacity to the system in 2028. Therefore, to be
considered incremental capacity, any new market purchase must be either (1) imported
on incremental transmission rights not already assumed, or (2) delivered directly to the
system at the Company's border. The regional transmission system around and including
Idaho Power's system has been constrained over the past several years. Until new
transmission is built, it is unlikely that additional long-term firm transmission capacity,
beyond what Idaho Power has already reserved, will become available in any significant
volumes. Transmission can become available on occasion, and when it does, Idaho
Power evaluates purchasing it. To date, no other long-term firm transmission has been
made available in volumes sufficient to address the remaining 2028 deficits.
25. The second option, energy purchases that the seller can deliver to Idaho
Power's border, are also extremely limited and transmission-dependent. There are few
counterparties that have firm transmission to deliver the generation to the Company's
border at a point where Idaho Power also has internal firm transmission with which to
deliver the purchase to load. Besides transmission, a market purchase also requires an
entity with surplus generation capacity to be willing to commit that capacity to a sale
multiple years in advance. Idaho Power has already executed a market purchase
agreement for 200 MW for the summer period (June— September) starting in 2026, which
IDAHO POWER COMPANY'S REPLY COMMENTS - 15

will be in effect in 2028. No market purchase bids were submitted in the 2028 RFP. The
Company continually evaluates market dynamics and potential purchase opportunities to
ensure Idaho Power can economically serve load with the least-risk resources, whether
that is market purchases or a resource.
26. Finally, contrary to IIPA's assertion, demand-side options were considered
as an interim alternative to the Bennett Gas Expansion Project. The 2025 IRP evaluated
additional demand response potential in the Company's service area, grouping the
expansion of Idaho Power's existing programs and other potential programs into similar
price and characteristic buckets for analysis alongside other potential resource additions.
Demand response was available for selection in the Aurora model in 10 MW and 5 MW
amounts for existing program expansion and storage programs, respectively. The 2025
IRP Preferred Portfolio includes 10 MW of demand response as a cost-effective resource
alternative in 2029 and another 10 MW in 2042. In addition to only 10 MW of demand
response being identified as a cost-effective resource addition in 2029 and 2042, Idaho
Power did not receive any demand response bids into the 2028 RFP. The record reflects
that Idaho Power did evaluate whether demand-side measures provided the ability to
defer resource procurement efforts.35
27. Deferral of the Bennett Gas Expansion Project is not an option. The
Company has provided evidence of a 265 MW capacity deficiency in 2028 which grows
to 577 MW in 2030 based on Idaho Power's most up-to-date load and resource inputs,
assumptions thoroughly reviewed by Staff and found to be reasonable and supported.36
With a contract execution and construction period of two to six years to bring a resource
31 IIPA Comments, page 9.
36 Staff Comments, page 3.
IDAHO POWER COMPANY'S REPLY COMMENTS - 16

online, "immediate approval is necessary to avoid harm,1137 contrary to IIPA's declaration,
as absent a resource, the Company would be unable to meet system reliability
requirements, impacting the ability to provide continued safe, reliable electric service to
customers.
D. AFUDC accrual for the Bennett Gas Expansion Project when procurement
activities begin is appropriate.
28. Recently, Idaho Power began incurring capital expenditures associated with
resource procurements earlier than in the past in order to secure a position in the queue
to purchase the recips for the Bennett Gas Expansion Project. Because Idaho Power has
not previously been in a position to incur costs associated with resource procurements
prior to receiving a CPCN, the Company is requesting approval to begin the accrual of
AFUDC once the Bennett Gas Expansion Project was deemed viable and expenditures
associated with the resource procurement were incurred. Idaho Power is not, however,
seeking a prudence determination of any project costs at this time, as asserted by IIPA,38
rather recognition of the required upfront investments made by the Company in pursuit of
cost-effective, necessary resources to safely and reliably serve customers. Idaho Power
appreciates Staff's findings of the Company's request to be reasonable and support for
authorization to commence accrual AFUDC when the Bennett Gas Expansion Project
procurement activities began.39
29. In addition to the AFUDC accrual request specific to the Bennett Gas
Expansion Project, Idaho Power also requested approval of the commencement of the
accrual of AFUDC on capital expenditures associated with future resource procurements
3' IIPA Comments, page 9.
ss Id., page 7.
39 Staff Comments, page 7.
IDAHO POWER COMPANY'S REPLY COMMENTS - 17

at the time the project is deemed viable by the Company. For clarification, Idaho Power
has not made additional investments to procure additional resources for any other final
shortlisted projects bid into the 2028 RFP prior to obtaining OPUC approval.40 While Idaho
Power believes its request aligns with the Federal Energy Regulatory Commission's
guidance on the commencement of AFUDC accrual, if the Commission declines to
approve the Company's request for broad approval of the same, the Company believes
Staff's recommendation that Idaho Power follow a similar approach used in this case, and
request approval for AFUDC accrual on resource procurement activities as part of the
CPCN request related to the corresponding resource, is reasonable.41
E. Cost recovery associated with the Bennett Gas Expansion Project is more
appropriately contemplated in a future rate proceeding.
30. As part of their review of Idaho Power's request in this case, and because
the Bennett Gas Expansion Project was a benchmark bid and will be a self-build project,
Staff thoroughly analyzed the cost-effectiveness of the project noting that, as the only
dispatchable resource on the 2029 Bids final shortlist, replacement would require
"significantly larger amounts of variable energy resources and energy storage
resources."42 Considering the portfolio cost modeling performed as part of the 2029 Bids
final shortlist, the results indicate that a portfolio without the Bennett Gas Expansion
Project is as much as higher on a net present value basis than a portfolio
with the Bennett Gas Expansion Project, providing evidence of the cost-effectiveness of
the resource.
40 Staff Comments, page 7.
41 Id. pages 7-8.
42 Id., pages 4-5.
IDAHO POWER COMPANY'S REPLY COMMENTS - 18

31. In their Comments, Staff notes that because the Bennett Gas Expansion
Project is a self-build project, some of the common cost overrun protections do not exist,43
such as those included in a Build Transfer Agreement, and that the Company would likely
request cost recovery of full project costs. Thus, Staff proposes that, to assist in resolving
any cost differences in a future filing, the bid details provided in Confidential Attachment
A be utilized. Idaho Power appreciates Staff's concerns with potential cost overruns and
supports the recommendation that prudence will be based on final actual costs when the
Company seeks recovery in rates.44 However the Company notes that the details
provided in Staff's Confidential Attachment A include bid pricing and project costs at
various stages of the Engineering, Procurement, and Construction contracting process
and therefore are not reflective of final contract pricing. Idaho Power has completed an
analysis, provided to parties through discovery, that quantified the 20-year portfolio costs
associated with a 30 percent increase in the capital cost of the Bennett Gas Expansion
Project. As illustrated, a 30 percent increase to the levelized cost of capacity of the project
would increase total project costs by . However, the portfolio cost difference
between the top performing portfolio, which includes the Bennett Gas Expansion Project,
and the top performing portfolio that excludes the Bennett Gas Expansion Project, is still
nearly .45 That is, even with a 30 percent increase in project costs, the Bennett
Gas Expansion project remains a least-cost resource addition.
32. As Staff noted, the Company is not seeking a binding ratemaking treatment
in this proceeding; Idaho Power's request of the Commission is not to "prejudge cost
43 Id., page 5.
44 Id., page 8.
41 See Response to Staff's Request No. 21.
IDAHO POWER COMPANY'S REPLY COMMENTS - 19

causation, prudence, or risk allocation" to existing customers as cautioned by IIPA.46
Rather a prudence determination will occur when Idaho Power seeks cost recovery in a
future proceeding. Moreover, as part of the settlement approved in the Company's last
general rate case,47 Idaho Power committed to initiating a single-issue case related to the
class cost-of-service methodology, no later than the end of the first quarter of 2026, which
will provide all interested stakeholders, including IIPA, with the opportunity to present any
cost allocation and assignment concerns for the Commission to address. Issuance of a
CPCN for the Bennett Gas Expansion Project would not "improperly prejudge cost
causation"48 but rather an indication of the assessment of the Company's annual capacity
positions and the selection of a least-cost, least-risk resource necessary to meet any
capacity needs.
III. CONCLUSION
33. Idaho Power acknowledges and appreciates IIPA and Staff's review of the
Company's application and respectfully requests that the Commission (1) accept Staff's
recommendations to issue a CPCN for the Bennett Gas Expansion Project and approve
AFUDC accrual for the Bennett Gas Expansion Project upon initial procurement activities,
(2) accept the Company's request to approve the commencement of the accrual of
AFUDC on capital expenditures associated with future resource procurements at the time
the project has been deemed viable by the Company, or, in the alternative, adopt Staff's
recommendation that Idaho Power request approval for AFUDC accrual on future
resource procurement activities as part of the CPCN request related to the corresponding
41 IIPA Comments, page 7.
47 Case No. IPC-E-25-16, Order No. 36892.
48 IIPA Comments, page 2.
IDAHO POWER COMPANY'S REPLY COMMENTS -20

resource, and (3) reject IIPA's unwarranted proposal to deny or defer the issuance of a
CPCN. The evidentiary record demonstrates that the Bennett Gas Expansion Project
meets the statutory standard of public convenience and necessity because it enables the
Company to meet its reliability obligations for all customers the Company is required to
serve. The Bennett Gas Expansion Project is a prudent and least-cost, least-risk system
resource required to help meet the identified capacity deficit in 2028.
DATED at Boise, Idaho this 6t" day of February 2026.
DONOVAN E. WALKER=�
Attorney for Idaho Power Company
IDAHO POWER COMPANY'S REPLY COMMENTS -21

CERTIFICATE OF SERVICE
I HEREBY CERTIFY that on the 6th day of February, 2026, 1 served a true and
correct copy of Idaho Power Company's Reply Comments upon the following named
parties by the method indicated below, and addressed to the following:
Commission Staff Hand Delivered
Jeffrey R. Loll U.S. Mail
Deputy Attorney General Overnight Mail
Idaho Public Utilities Commission FAX
11331 W. Chinden Blvd., Bldg No. 8 FTP Site
Suite 201-A (83714) X Email jeff.loll(a�puc.idaho.gov
PO Box 83720
Boise, ID 83720-0074
Micron Technology, Inc. Hand Delivered
Austin Rueschhoff U.S. Mail
Thorvald A. Nelson Overnight Mail
Austin W. Jensen FAX
Holland & Hart LLP X Email darueschhoff(cDhollandhart.com
555 17th Street, Suite 3200 tnelson(q)_hol land ha rt.corn
Denver, CO 80202 awjensen(a-)_hollandhart.com
aclee(o-)_hollandhart.com
ka roach(a-)_hol land hart.com
Idaho Irrigation Pumpers Association, Hand Delivered
Inc. U.S. Mail
Eric L. Olsen Overnight Mail
ECHO HAWK & OLSEN, PLLC FAX
505 Pershing Avenue, Suite 100 X EMAIL elo(a-echohawk.com
P.O. Box 6119 Taysha echohawk.com
Pocatello, ID 83205
Lance Kaufman, Ph.D. Hand Delivered
2623 NW Bluebell Place U.S. Mail
Corvallis, OR 97330 Overnight Mail
FAX
X EMAIL lance(a)aegisinsight.com
Stacy Gust,
Regulatory Administrative Assistant
IDAHO POWER COMPANY'S REPLY COMMENTS -22