20251202Closing Brief.pdf

RECEIVED
DECEMBER 2, 2025
Clean Energy Opportunities for Idaho IDAHO PUBLIC
UTILITIES COMMISSION
Kelsey Jae (ISB No. 7899)
Law for Conscious Leadership
521 E 41 st St,Apt. 506
Garden City, ID 83714
Phone: [phone]
1kelsey0)kelseyjae.com
Attorney for Clean Energy Opportunities for Idaho
BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
IN THE MATTER OF IDAHO POWER CASE NO. IPC-E-24-44
COMPANY'S APPLICATION FOR
APPROVAL OF SPECIAL CONTRACT Clean Energy Opportunities for Idaho
AND TARIFF SCHEDULE 28 TO
PROVIDE ELECTRIC SERVICE TO Closing Brief
MICRON IDAHO SEMICONDUCTOR
MANUFACTURING (TRITON) LLC.
The Triton FAB load is transformational, unlike any existing customer. The magnitude of
the incremental FAB load makes this a case of first impression. As a matter of first
impression this case requires Commission policy updates to address the transformation
that is now upon us.
There are multiple open issues in this docket, but the key issue is who pays for resources
which are solely caused by the FAB yet not solely used by the FAB. Resolving how to
allocate the costs of the incremental bulk power system (Generation &Transmission,
"G&T") resources caused by the FAB load necessitates a more thorough review than Idaho
Power("the Company" or "IPC") has provided.
The ESA should not be approved as submitted. In section 3.1 of this briefing, CEO
recommends three ESA changes: to implement TOU energy rates, to clarify that any
"additional transmission" costs are not limited to those needed as traditional
"Interconnection Facilities", and to explicitly allow the ability to update the method used
to determine FAB Energy and Demand charges. In addition, CEO requests that additional
reviews should be ordered to address open matters enumerated in section 3.2. Failing to
fully address these matters could harm existing IPC customers in this instance and will do
further damage when the next very large load customer arrives.
CEO's brief will address these matters in more detail below.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 1

Clean Energy Opportunities for Idaho
Table of Contents
1 THE CASE AS PRESENTED HAS MULTIPLE DEFICIENCIES AND IS INADEQUATE TO SUPPORT ESA
AND SCHEDULE 28 APPROVAL. 2
1.1 NO-HARM SCENARIOS-THE SINGULAR"BEST CASE"SCENARIO NO-HARM ANALYSIS THE COMPANY RAN WAS
INSUFFICIENT TO JUSTIFY THE FAB RECEIVING EMBEDDED DEMAND RATE TREATMENT. ALTERNATE SCENARIOS PRODUCE
DRAMATICALLY DIFFERENT OUTCOMES THAT SHOW SUBSTANTIAL HARM TO EXISTING CUSTOMERS. 2
1.2 TRANSFORMATIONAL,NOT TRADITIONAL-THE FAB LOAD IS SO MUCH LARGER THAN EXISTING CUSTOMERS THAT
TRADITIONAL SPECIAL CONTRACTS APPROACHES ARE AN INAPPROPRIATE BASIS FOR JUSTIFYING THE USE OF TRADITIONAL COST
ALLOCATION METHODS. 7
1.3 PERVERSE INCENTIVES-IN THIS ERA WHERE IOUS COMPETE FOR LARGE NEW LOAD"COMPETITIVE"CUSTOMERS,
PROTECTION OF EXISTING"CAPTIVE"CUSTOMERS IS AT RISK. 10
1.4 BAD PRECEDENT-THE PROPOSED FAB COSTALLOCATION METHODS LIMIT FAIR TREATMENT FOR EXISTING
CUSTOMERS FROM BOTH THE FAB AND SUCCESSIVE LARGE LOAD CUSTOMERS. 12
2 NEW VERY LARGE CUSTOMERS RAISE SEVERAL NEW ISSUES THAT REQUIRE CLARIFICATION AND
POLICY GUIDANCE FROM THE COMMISSION. 13
2.1 WHAT CONSTITUTES A NEW LARGE LOAD? 13
2.2 WHEN DOES SUCH A NEW LARGE CUSTOMER BECOME"EXISTING"AND NO LONGER"NEW"? 14
2.3 SHOULD INCREMENTAL INFRASTRUCTURE COSTS THAT WOULD NOT OCCUR BUT FOR THE NEW LOAD BE CHARGED
TO THAT NEW CUSTOMER? 14
2.4 HOW SHOULD A NEW LARGE LOAD CUSTOMER PAY FOR THE INCREASED REVENUE REQUIREMENTS IT CAUSES DUE
TO UPWARD PRESSURE ON THE COMPANY'S FINANCING COSTS AND RETURN ON EQUITY(ROE)? 15
2.5 HOW ARE ANY INCREMENTAL COSTS A NEW LOAD CAUSES TO BE MEASURED AND ALLOCATED TO THAT
CUSTOMER? 15
2.6 COULD SPECIAL RATE DESIGN CONCERNS RELATED TO NEW VERY LARGE CUSTOMERS BE REDUCED OR
ELIMINATED BY CUSTOMER SELF-SUPPLY OR VIA FUNDING THROUGH A CIAO"LOAN"? 15
3 SUMMARY RECOMMENDATIONS AND REQUESTS 16
3.1 CHANGES TO THE ESA 17
3.2 STAFF LEAD FOLLOW-ON PROCESS 17
1 The case as presented has multiple deficiencies and is inadequate to
support ESA and Schedule 28 approval.
1.1 No-harm scenarios-The singular"best case"scenario no-harm analysis the Company
ran was insufficient to justify the FAB receiving embedded demand rate treatment.
Alternate scenarios produce dramatically different outcomes that show substantial harm
to existing customers.
Company witness Ms. Aschbrenner explained that the Company went through a two-step
process to develop the embedded demand cost approach it proposes for the FAB.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 2

Clean Energy Opportunities for Idaho
First, the Company conducted a no-harm analysis purportedly showing that allocating both
existing and incremental G&T costs on a load ratio basis would not harm existing
customers by raising the rates they pay as demand charges. Second, the Company
developed a marginal energy cost and embedded demand cost rate structure for the ESA.
Other no-harm scenarios and rate design alternatives were not presented.
The Company's no-harm analysis is the prime justification for proposing that the FAB not
be directly charged for the incremental G&T costs it causes.' As will be shown below, that
no-harm analysis is fatally flawed and the conclusion that granting the FAB embedded
demand cost treatment is not warranted.
Table 3 . LTCE Resource Selection `With vs . Without Micron"
With Micron vs.Without Micron
Geothermal
Nuclear
Year Coal Gas/H2 Wind Solar Storage OR EE Biomass
2026 - - - - - - - -
2027 - - 600 100 100 - - -
2028 - - - 100 200 - - -
2029 - 100 100 - 155 10 - -
2030 - 250 - - - - - -
2031 - - - - - - 8 -
2032 - (50) - - - - - -
2033 - (50) - 100 45 - 21 -
2034 - - - - (5) - 6 -
2035 - - - - - - 5 -
Sub Total - 250 700 3W 49S 10 41 -
Figure 1-List of FAB caused incremental generation resource requirementS2
It is not contested that serving the FAB load will require incremental generation resources
(as displayed in Figure 1). These resources will be very expensive. Using unit prices for
supply-side resources taken from the 2025 IRP, the FAB would cause IPC to procure (and
rate base) more than $2 billion worth of additional generation resources3.
' CEO notes additional attempts to justify the embedded cost treatment by comparison,among other things,
to rate treatment employed in the Lamb Weston and Brisbee special contracts. See section 1.2 below.
2 IPC-E-24-44 Ellsworth Surrebuttal page 9.
3 Calculated assuming that all the solar resource requirements would be procured via PPA rather than IPC
owned and only 300 MWs of the wind resource would be IPC owned with the remainder procured via PPA for
consistency with the 2025 IRP assumptions.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 3

Clean Energy Opportunities for Idaho
The no-harm analysis the Company relied upon uses calculations based on the
assumption that after the end of the ramp up period the FAB will never operate at less than
full capacity over the next two decades. That full capacity implied a level of power
consumption greater than 4 terawatt-hours/year over the remainder of the 20 year test
period. At that level of consumption the FAB would attract existing G&T fixed costs in an
amount that exceeds the cost of the incremental generation resources FAB requires. CEO
refers to the Company's no-harm run as one based on the"best case"scenario. A
comprehensive and sufficient no-harm analysis should include multiple scenario analyses
rather than just a single, best-case set of assumptions.
Under this"best case" no-harm scenario, the FAB could absorb enough fixed costs from
existing G&T resources to offset the incremental cost of the new G&T resources it requires.
If the demand charges associated with the > $2 billion in FAB caused incremental
generation resource costs were to be spread across a lower amount of FAB consumption, a
dramatically different result arises.
In a no-harm scenario where calculations were based on an annual FAB power
consumption pattern that aligns with the declining monthly billing demand quantities,4 the
total amount charged to FAB declines almost 50%. Because such lower levels of FAB
consumption do not reduce the cost of the FAB caused incremental generation resources,
those costs are shifted to existing customers. At a minimum billing demand level of FAB
power consumption, more than $1 billion of FAB caused incremental generation costs
are shifted to existing customers.s
While this billion-dollar cost shift alone should disqualify the interpretation the Company
made on its no-harm analysis, other substantive deficiencies exist in the analysis method
IPC utilized. One has to do with the treatment of Transmission related fixed costs. Both
IIPA and CEO raised concerns about the Company's refusal to consider that some portion
of the Transmission costs that IPC models as not changing between its"with FAB"and
"without FAB" runs should actually be shown to vary between those runs.
4 IPC-E-24-44 Application Exhibit 2-2.
5 CEO is using only general references to amounts of cost transfer under other than"best case"no-harm
scenarios. The Company marked Exhibits 1 and 3 no-harm excel spreadsheets as Confidential in their
entirety. CEO challenged the extensive confidentiality protections claimed over the data in the spreadsheet.
See Confidentiality Challenge filed on September 15,2025. Prior to this challenge CEO requested clarity via
email on August 23rd and received a response from the Company. Follow-up emails regarding the challenge
were exchanged on September 24th and 26th. The Company replied to the challenge on October 1 st but did not
file its reply. CEO counter replied on October 9th,followed-up on October 17th and received additional unfiled
comments from the Company on October 21 st. Idaho Power continues to claim"sensitive business
information"protection over nearly all of the data and purports to require documents citing this data be
submitted confidentially or in redacted form.CEO continues to dispute the appropriateness of this extensive
secrecy. Here,CEO is choosing to reference the no-harm analysis using general terms rather than specific
numerical values to avoid the stated requirement to submit this Closing Brief in redacted form.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 4

Clean Energy Opportunities for Idaho
CEO focused on the timing of the buildout of Mayfield substation and extending the 500kV
line running from Hemmingway to Mayfield to serve the massive load growth in south-east
Boise.6 IIPA raised concerns about the costs associated with new transmission lines
designed to access low cost energy markets. IPC ignored both sources of incremental
transmission costs in its no-harm analysis.
Either incremental transmission capacity was needed to serve the FAB and should be
included in the no-harm analysis, or the excessive magnitude of transmission capacity in
the Company's resource plan was selected to also improve energy costs. If the latter,then
it is neither fair nor reasonable to allocate transmission infrastructure to the energy-
intensive FAB as though those costs are 100% capacity related.
An additional open issue arises from the fact that the no-harm analysis was calculated
based on 2023 and then again on 2025 IRP conditions. In the IRP the Company only
models new loads from committed large load customers who have entered into
procurement or construction agreements with Idaho Power. This results in the 2025 IRP
only reflecting about 300MWs of new large customer load growth beyond the FAB load.' By
contrast, IPC President Lisa Grow stated during the Company's 2Q25 earnings conference
call:
,,The pipeline of prospective customers on our list exceeds our all-time peak load of around
3,800 megawatts."
The no-harm analysis the Company ran to justify the rate design in the FAB ESA assumes
that the FAB will get credit for sopping-up substantial quantities of currently under-utilized
G&T capacity and their related demand costs. If the Company adds 3GWs of pipeline
customers, they too will use up remaining under-utilized G&T capacity. Will those
customers get a pro-rata share of the credit for sopping-up cost offsets that have already
been credited to the FAB? If the potential for using up under-utilized G&T capacity is
already incorporated in the FAB's rate design,will acceptance of the proposed FAB ESA
treatment have produced an effective"first in time, first in right"allocation system?
Company witness Mr.Anderson states:
The ESA does not permanently fix demand-related pricing. Instead, it reflects cost
responsibility.'
The Company would have a FAB demand cost allocation method—referred to above as
"cost responsibility" -that combines the incremental G&T costs the FAB causes with pre-
existing embedded G&T costs and spreads those costs via a load-ratio share. A more
s IPC-E-24-44 Heckler Rebuttal pages 5 and 6.
7 2025 IRP Appendix A pages 23 and 24.
8 Lisa Grow, IDACORP 2Q 2025 Earnings Conference Call,July 31,2025.
9 IPC-E-24-44 Anderson Direct page 17.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 5

Clean Energy Opportunities for Idaho
robust no-harm review shows that such an allocation method would clearly harm existing
customers should future FAB loads decline at a rate considered in the ESA.
CEO has suggested a modification to the proposed demand costing method that could
hold the existing customers harmless. In CEO's approach, the FAB would be charged for
all the incremental G&T costs it is causing. The FAB could also be credited for any portion
of existing G&T costs they were absorbing up to a level that equals but does not exceed the
incremental costs they caused.10
CEO's suggested approach would hold existing customers harmless from G&T costs that a
new very large customer causes. It would also finesse the first in time, first in right issue by
allowing flexibility in how multiple future new large loads are credited for sopping-up some
of the costs of existing underutilized G&T capacity.
IIPA and CEO previously provided analyses that suggest not being charged the full cost of
the incremental resources the FAB will require produces a greater than $1 billion benefit to
FAB. CEO believes policy guidance on how to balance charging new megaload customers
for the incremental costs they cause and how and to what extent existing customers
should be shielded from these effects is clearly needed.
CEO suggests that policy clarifications from the Commission are warranted at this time on
several matters, including:
• Should new megaload customers exclusively pay for all incremental costs their new
Load causes even if such a rate design provides benefits to the existing customers
that those customers would not receive absent the new load?
• Should new megaload customers pay for their incremental costs but be granted
some offsetting credit in their rate structure to reflect amounts of fixed charges the
new customer attracts that reduce costs for existing customers?
• Should the extent of any such credit be limited to the amount required just to keep
existing customers"whole"?
The Company suggests that relevant issues raised in this case are being fully vetted and the
ESA should be approved without further delay." In contrast, CEO concludes that the
proposed ESA and its associated Schedule 28 rate features merit more extensive review
and modifications in order to adequately serve the public's interest.12
10 IPC-E-24-44 October 28 2025 Hearing transcript, Heckler Corn page 803.
""Further review beyond what is already scheduled as part of the Micron FAB case proceedings would only
postpone resolution of issues that are already being thoroughly vetted." IPC-E-24-44 Aschenbrenner
Surrebuttal page 11.
12 IPC-E-24-44 Heckler rebuttal page 2.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 6

V Clean Energy Opportunities for Idaho
1.2 Transformational, not traditional—The FAB load is so much larger than existing
customers that traditional special contracts approaches are an inappropriate basis for
justifying the use of traditional cost allocation methods.
CEO pointed out the core unresolved issues in this case in March13 - The FAB represents a
transformational load, so fundamentally different from all other of the Company's
customers that traditional cost allocation methods are not adequate.
There are many examples of how the Company and FAB counsel referred to traditional
approaches for allocating the costs of shared system resources to justify ignoring the Long-
standing"cost causer pays" principle. For example,while on the witness stand IIPA
witness Dr. Kaufman was asked repeatedly about whether FAB would solely use power
generated by the new resources its load will cause.
Similarly, in her direct testimony Company witness Ms. Aschbrenner states:
"Idaho Power does not procure generation or transmission resources that are solely
dedicated to an individual customer".14
Company witness Mr. Ellsworth comments that the Mayfield substation is not:
"solely attributable to Micron FAB's load."15
Company witness Mr. Anderson also focuses on the topic stating:
"planned transmission projects are not solely necessitated by Micron FAB...These are
system resources-not facilities dedicated solely to Micron FAB. System generation and
transmission are planned,procured, and operated to optimize service for all customers.
Assigning costs by vintage rather than by cost causation is not an approach the Company
supports.16
Apparently in contrast, in her direct testimony Company witness Ms. Aschbrenner notes
that:
"It has been a long-standing policy of the Commission that, to the extent feasible, costs
should be assigned to a cost-causer to mitigate upward pressure on rates that would
otherwise exist."17
'3 IPC-E-24-44 March 21,2025 comments.
14IPC-E-24-44 Aschbrenner Direct page 9(emphasis added).
15 IPC-E-24-44 Ellsworth Surrebuttal page 4(emphasis added).
16 IPC-E-24-44 Anderson Surrebuttal page 7(emphasis added).
"IPC-E-24-44Aschbrenner Direct, page 8.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 7

Clean Energy Opportunities for Idaho
In response to questioning by counsel for ICIP, Ms. Aschbrenner confirmed that the
Company's policies support this Commission policy and are implemented that:
"growth pay[s]for growth.
and that:
"There has not been a policy in the State of Idaho, nor has that been accepted, that
incremental generation is assigned directly to customers. Generation resources and
transmission resources are utilized by all customers on our system.""
As discussed in the no-harm section above, the FAB load is so large that it does solely
require additional infrastructure resources even if in their use they will not solely serve FAB
Load. It is feasible to assign these costs to the cost-causer. The lack of a previously
established policy related to assigning incremental generation costs directly to particular
customers is no justification for not doing so in this case.
Under a different theory, Company witnesses also attempt to justify the proposed cost
allocation method for determining demand pricing structure proposed for the FAB by
comparing the proposed FAB costing method to methods approved for Lamb-Weston and
Brisbie contracts.
Specifically,they note consistency with "traditional cost-of-service principles and
Commission precedent"20 when proposing FAB demand charges calculated on an
embedded (rather than incremental) system capacity cost basis. CEO finds these
comparisons largely specious and not persuasive regarding guidance on how FAB demand
costs should be allocated.
For example, the Company references the existing Brisbie Special Contract. The manner in
which Brisbie procures RECs from a dedicated resource under a "Clean Energy Your Way"
structure is not in anyway analogous to the rate design in the proposed FAB ESA. The
comparison of the FAB to Brisbie is not informative regarding FAB rate design.
Comparison to the costing methods in the Lamb Weston case is also problematic.
Ironically, suggesting the FAB demand costs should be based upon embedded system
costs appears to be directly contrary to the rationale used in developing the Lamb Weston
Special Contract. Using the Lamb Weston rationale argues for a FAB rate design based on
incremental rather than embedded costing.
'$IPC-E-24-44 October 28 2025 Hearing transcript, page 370.
19 IPC-E-24-44 October 28 2025 Hearing transcript, pages 371 and 372.
21 IPC-E-25-16,Anderson direct page 7.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 8

Clean Energy Opportunities for Idaho
Three quotes from the Application for a Special Contract with Lamb Weston (IPC-E-23-18)
present this matter clearly. In section 15 of the Application in that case, under a sub-
grouping of topics related to "Pricing Structure"the Company asserts that it has attempted
to:
develop pricing that would reduce potential cost-shifting and result in Lamb Weston fairly
contributing to incremental system costs necessary to serve their new load.21
Later in Application section 19, the Company explains that the application of marginal
energy costs in the Lamb Weston ESA is appropriate because the Company was energy
constrained at the time the ESA was submitted, stating:
Because the Company's system is currently facing near-term energy constraints, it is
expected that the incremental load will cause an increase in the cost to provide energy to
all customers.As such, the Company proposes to price Block 2 Energy on a marginal cost
basis as more fully set forth below.22
In contrast, in section 17 of the Lamb Weston application, the Company explains that the
use of demand rates based on embedded costs is warranted because Lamb Weston was a
relatively small new load and not likely to require new generation or transmission
investments:
"The expansion of the Lamb
Weston Facility is expected to Lamb Weston's peak load represents.7%of IPC
result in an approximately average system load. By comparison,at> 18%of
14,000 kW increase in power average annual total system load by 2030,the FAB
requirements, which is a summer load represents a 25 times larger share.
relatively small increment as The two loads are not comparable.
compared to Idaho Power's
20.0% 18.1%
system load and is not expected
to alone drive new generation 2 16.0%
or transmission investments.As
a result, the Company N 12.0°r°
developed the demand rates to o 8.0%
reflect embedded costs."23 6
4.0%
2 0.7%
The FAB load is not a "small 0.0%
increment" new power requirement, Lamb Weston FAB
and the FAB load does alone drive Comparison of each company's peak Spec ialContract load expressed
new generation or transmission asa%age of the Company's annual average total system load.
investments.
Figure 2—Lamb Weston and FAB are not comparable
2' IPC-E-23-18,Application section 15 page 7(emphasis added).
22 IPC-E-23-18,Application section 19, page 9(emphasis added).
23 IPC-E-23-18,Application section 17, pages 8 and 9(emphasis added).
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 9

Clean Energy Opportunities for Idaho
At seven/tenths of 1% of average system load, the incremental generation and
transmission resources Lamb Weston's Special contract would require (if any)were
deemed too small to warrant an incremental demand cost allocation.
By contrast the FAB alone will cause multi-billion dollars of generation investments"."
At >18% of average system load, the incremental generation and transmission resources
that the FAB load will require are not comparable to the Lamb Weston requirements.
The fact that the Company chose to price demand for Lamb Weston based on embedded
costs does not justify a similar embedded demand cost treatment for the FAB.
1.3 Perverse Incentives- In this era where IOUs compete for large new load"competitive"
customers, protection of existing"captive"customers is at risk.
Growth in power required to serve new very large customers is changing the electricity
market nationwide. We are in a new era of exploding demand for electric power. And in this
new era, biases inherent to the traditional Investor Owned Utility(IOU) incentive structure
become increasingly problematic. These biases serve to favor the IOU and new large load
customers at the expense of existing customers.
In the past, IOUs faced a low but relatively stable increase in demand for their product.
They didn't grow fast but were reliable sources of earnings and related dividend payments.
Even then the IOU was incented to propose additions to its infrastructure (with related
increases in the rate base that drives its earning capacity) but methods were developed to
balance that incentive.
Traditionally, careful resource planning, competitive procurements and CPCN review have
provided protection to the captive customers residing in the IOU's service territory. An IRP
identifies the need for additional resources. RFP based competition ensures good value
when the new resources are needed. And a CPCN review confirms the current need and
appropriateness of this particular resource to serve that need . Overall this regulatory
process protects the captive customers from excessive procurement the Company
incentives could otherwise produce.
What has recently changed the game is an element of competition between IOUs for a new
class of extremely large customers. Should these new customers choose to build within a
particular IOU's service territory the IOU could potentially justify massive increases in its
infrastructure and rate base. That's what is happening here, and the FAB is just the first of a
procession of new megaload customers coming to southern Idaho.
24 If the Company were to procure all the Gas/1-12,Wind,Solar and Storage resources shown on Table 3
directly(rather than via PPA)at the price per MW values in the 2025 IRP that sum of"capital costs"would
exceed$3.5 billion. With adjustment for resource requirements being met via PPA rather than IPC ownership
the capital costs for FAB required generation resources would exceed$2 billion.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 10

4'1d11,6, Clean Energy Opportunities for Idaho
The potential for new megaload customers justifying enormous increases in IOU earning
power is like spreading chum in front of financial analysts. IPC President Grow also
testified in the Company's most recent rate case:
... Idaho Power expects to double its rate base over the next four years."2'
This new condition presents a big new challenge for regulators. The financial structure
incents IOUs to propose low-rate contracts to new megaload customers in order to win the
new"competitive"customers to their service territories and support massive rate base
growth. A low rate structure benefits the new megaload customer. That customer's
decision to add its massive new load in the IOU's service territory benefits the IOU.
But what about the interests of existing captive customers that already take power in the
IOU's service territory? How do regulators balance the interests of the Company's existing
captive customers with the benefits new customer growth can provide?"
CEO Policy Director Heckler has testified that the proposed ESA represents a sweet deal27
for both parties. Figure 3 shows that adding the incremental generation resources needed
to serve the FAB load will provide IPC an opportunity to earn an extra $1.5 trillion over the
next 20 years.
Over a 20-year ESA duration,IPC would receive>$1.5 bllion of incremental return on investment
on Company purchases of the FAB caused incremental generation resources presented in Mr.
Ellsworth's testimony(excludes all solar&most of the wind as PPAs)
$160,000,000
$120,000,000
$80,000,000
$40,000,000
$-
I, co 0) N M ' 'D r M 0 O .--I N M V '0
N N N M M M M M M M M M M a 8 8 8 9 a a
N N N N N N N N N N N N N N N N N N N N
Annual return on investment on net depreciated value of incremental generation resources
Figure 3-Rate base increases to meet incremental FAB generation requirement are highly
beneficial to IPC earnings potential
25 Lisa Grow Direct, IPC-E-25-16,24:14-15(May 30,2025).
26 For related discussion see Extracting Profits from the Public: How Utility Ratepayers Are Paying for Big
Tech's Power Eliza Martin and Ari Peskoe, Environmental and Energy Law Program, Harvard Law School
March 2025.
27 IPC-E-24-44 October 28 2025 Hearing transcript, Heckler Com, page 802.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 11

1p Clean Energy Opportunities for Idaho
In addition to the very favorable
overall implied rate structure offered 2025 IRP forecasts marginal energy costs to
decline more than 60%over FAB lifetime
to the FAB in the ESA, a different but
Boor
equally concerning implication of the
proposed ESA was raised regarding 80%
the option it effectively grants the FAB 60%
to transition out of being charged
aOX.
marginal energy rates.
28
20%
The 2025 IRP projects substantial 0%
declines in energy prices as SWIP and N
N N N N M M M M M M M M M M
0 0 0 0 0 0 0 0 0 0 0 0 0 o g 8 8 8 8
N N N N N N N N N N N N N N N N N N N N
B2H improve market access in the Annual marginal enegy cost as a%age of2026value
next decade. —
Figure 4-Improved market access is forecasted to
drive down energy prices in the coming decades.
ESA terms imply that energy consumption at the FAB will rise over a ramp-up period in the
remainder of this decade and then could plateau during the following decade and a half.
Even a cursory review of the data shown in Figure 4 suggests that the option to choose
whether to remain at marginal energy prices or convert to an embedded energy rate around
2030 grants a substantial benefit to the FAB.
The rational for charging marginal energy rates to the FAB was based on a belief that the
FAB would increase energy demand, that the increase in energy demand would cause
energy prices to rise, and that the FAB would absorb the energy price increase. The 2025
IRP forecasts flip that rationale on its head. If the IRP forecasts are correct, in the 2030s
the ESA effectively grants the FAB the choice to buy its energy at a rate that is lower than
the overall energy cost charged to existing customers.
The FAB is proposed to get a very low demand rate and the Company gets a very large
increase in its return on investment. The FAB will ostensibly face a marginal price for its
energy but even the ESA provides a concerning"option"to the FAB on that matter. The
proposal in the ESA is clearly good for the parties to the ESA contract. Absent changes to
that ESA and subsequent efforts to resolve related open issues, CEO concludes that
approval of the ESA as proposed is not in the public interest.
1.4 Bad Precedent-the proposed FAB cost allocation methods limit fair treatment for
existing customers from both the FAB and successive large load customers.
28 See IPC-E-24-44 Heckler Rebuttal page 11.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 12

Clean Energy Opportunities for Idaho
In rebuttal testimony CEO raised concerns about the precedential risk that could arise
from the FAB ESA.29 As detailed above, CEO believes the FAB can be clearly distinguished
from any other customer in the Company's service territory. Terms in section 13.2 of the
proposed ESA appear to attempt to constrain Commission actions by requiring showings
that those actions are"nondiscriminatory". As a unique level of load the FAB is in a class of
one and has no analogous customer against which it would receive a discriminatory
treatment. However,the next megaload customer is not going to be in a class of one and
will have a basis for arguing that they are being discriminated against if they don't get
treatment analogous to that provided to the FAB.
Approval of the ESA as proposed without addressing the open issues delineated in the brief
section below may prove unduly constraining on future Commission decisions. With
billions of dollars riding on how FAB open issues are resolved, CEO sees a substantial risk
of a future megaload customer suing to receive FAB like treatment.31 Approval of the ESA
as proposed would provide a dangerous precedent. For that and other reasons, the ESA
should not be approved without modification.
2 New very large customers raise several new issues that require
clarification and policy guidance from the Commission.
2.1 What constitutes a new large load?
IPC witness Ms. Aschbrenner explains that current Company policy considers any new
customer with an expected load greater than 1 megawatt a "large load customer"and any
customer with a load greater than 20 megawatts is of a size requiring a special contract31.
The FAB (and presumably many of the loads in the additional 3 gigawatt"pipeline") are
orders of magnitude larger than these classifications. In some states a size threshold is
used to define a large load, for example 75 or 100 megawatts. In other states an impact
test is employed, for example any new customer who requires infrastructure beyond what
current resource plans call for adding over the next decade is a new large customer.
As explained above, one of the fundamental distinctions between the FAB and other recent
special contract customers such as Lamb Weston is the need for additional resources to
serve the new FAB load. Guidance from the Commission regarding whether new
customers with certain size or impact characteristics should receive a different rate design
29 IPC-E-24-44 Heckler Rebuttal page 13.
30 See Heckler comment regarding Supreme Court, IPC-E-24-44 October 28 2025 Hearing transcript, Heckler
Com page 803.
3' IPC-E-24-44 Aschbrenner Direct page 5.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 13

Clean Energy Opportunities for Idaho
treatment would be very valuable in light of the likelihood of additional new large
customers being added in the Company service territory in the immediate future.
2.2 When does such a new large customer become"existing"and no longer"new"?
The ESA Staff witness Mr. Eldred raised concerns that the FAB not be allowed to transfer
from paying a marginal energy cost without a showing that doing such would not harm
other customers.32 The option for the FAB to initiate a transition out of the marginal energy
rate structure was timed to align with the end of the FAB load ramp period. One could
conclude that this implies that once a new customer reaches its full planned level of
consumption that the customer transitions to an "existing"customer status. Elsewhere in
the ESA the treatment of stranded asset risk via a declining minimum demand charge
suggests that some element of customer"newness"extends over a couple of decades.ss
Guidance from the Commission concerning how to distinguish new very large customers -
whether their size requires that they receive some special rate treatment and for how long a
duration such rate treatment is warranted - remain relevant open questions worthy of
Commission direction. Alternatives covered in section 2.6 below could effectively make
this issue moot.
2.3 Should incremental infrastructure costs that would not occur but for the new
load be charged to that new customer?
CEO contends that if the timing and/or magnitude of a new large customer's load
necessitates establishing or accelerating procurement of G&T system resources that
customer should pay such costs associated with those assets.
In Table 3 from Mr. Ellsworth's surrebuttal testimony the Company effectively
acknowledges that the FAB will necessitate procuring additional generation resources.
Both CEO and IIPA have also noted that the FAB will also cause the Company to incur costs
related to the timing and magnitude of additional transmission resources the FAB will need
that extend beyond the interconnection assets it has covered via Contributions in Aid of
Construction (CIAC) payments.
The FAB, as leader in a long pipeline of new very large customer loads, raises issues that
warrant policy review. Collectively these new loads will require massive new Company
funding. The rate and magnitude of this increase in funding need will likely raise the
Company's overall cost of capital. A rising ROE and/or debt cost will impact all customers.
32 IPC-E-24-44 Eldred Direct page 11.
33 IPC-E-24-44 Heckler Rebuttal page 12.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 14

jp Clean Energy Opportunities for Idaho
Should this increase in financing costs be charged to all customers or should it be
allocated directly to the new loads causing this cost increase?
2.4 How should a new large load customer pay for the increased revenue
requirements it causes due to upward pressure on the Company's financing
costs and Return On Equity(ROE)?
Large load customers put upward pressure on rates when they put upward pressure on
ROE. As a result existing customers allocated a higher portion of total revenue
requirements (e.g., residents) bear a higher portion of that increase. In IPC-E-25-16, the
Company requested a higher ROE. The Company attributed that ROE increase in part
because "high capital expenditures and increasing debt have recently worsened Idaho
Power's financial profile. Oral testimony on October 28 discussed how large customers
such as the FAB are driving increases in capital expenditures in a manner different than
existing customers.35
The proposed ESA fails to address the upward pressure on rates caused by the FAB's
disproportionate impact on ROE. CEO recommends that the Commission direct the
Company to propose remedies to this matter in the filing of the Class Cost of Service
docket stipulated in the IPC-E-25-16 settlement,the next GRC, or whatever proceeding
viewed most appropriate by the Commission.
2.5 How are any incremental costs a new load causes to be measured and
allocated to that customer?
Table 3 estimates the quantity, timing and types of incremental generation resources the
FAB would require through 2035 based on the set of assumptions underlying the 2025 IRP
estimating tool. The actual additional generation resources that the Company will procure
to serve load growth from the FAB will likely differ from the resource mix shown in Table 3.
If we have a situation in the future where resources are being added to serve multiple new
very large customers how will the actual costs incurred by the Company be allocated to the
individual customers? Because resources must be procured before the load they will serve
arises, how will costs incurred in one year be allocated to customers whose load
requirement drove those procurement needs but whose actual load only occurs in
subsequent years?
2.6 Could special rate design concerns related to new very large customers be
reduced or eliminated by customer self-supply or via funding through a CIAC"loan"?
34 IPC-E-25-16,Thompson Direct 32:21-22.
35 Cross Ex of Idaho Power witness Aschenbrenner by Pete Richardson.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 15

Clean Energy Opportunities for Idaho
Some states are requiring new very large customers to procure their own generation
resources at their cost thus reducing cost impacts to existing customers. CEO believes
that there are efficiencies that arise from having the Company directly procure incremental
G&T resources and thus suggested a CIAC based alternative.36
Traditional CIAC payments are made to cover costs for resources that only benefit the
customer making the CIAC payment (such as interconnection assets that only serve that
customer). The CIAC payment is made and the customer receives a direct benefit, such as
an interconnection. The customer will need interconnection for as long as it remains a
customer so the CIAC payment is not expected to be repaid to the customer.
CEO's suggestion focused on a slightly different approach. As has been discussed above,
bulk system G&T resources are inherently used by multiple customers, so a new very large
load customer would not get a sole benefit by making a CIAC payment to cover G&T costs.
Existing customers arguably do deserve some protection from stranded asset risk related
to costs the Company incurs to procure the additional G&T resources the new customer
requires.
CEO's suggestion is that the new large load customer be required to provide CIAC funding
in an amount adequate to cover the present value of that customer's future G&T resource
needs. Having made the CIAC payment, the new customer would not have caused the
embedded G&T costs to increase so that new customer could be charged embedded
demand rates.
A difference between CEO's suggestion and traditional CIAC payments is that the funding
be temporary. CEO suggests that the Company would gradually refund the CIAC payments
to the customer as a credit against its embedded cost billing. Simultaneously the
Company would shift the credited portion of the CIAC payment from a CIAC status and into
the Company's rate base. If the new customer did not ultimately procure the full amount of
power upon which its need for new G&T resources was predicated it would not receive a full
refund of its CIAC payments thus protecting existing customers from a stranded asset risk.
3 Summary recommendations and requests
The ESA should not be approved as proposed. Questions related to the FAB's share of
future revenue requirements should be resolved within a follow-on process set up within
this docket. The FAB should be provided some temporary pricing structure for use until
those questions are resolved and implemented.37
36 See IPC-E-24-44 Heckler Rebuttal page 10.
37 IPC-E-24-44 Heckler Surrebuttal page 19.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 16

Clean Energy Opportunities for Idaho
3.1 Changes to the ESA
CEO proposes at least three changes to the proposed ESA.
1. Revise Schedule 28 Time of Use (TOU) Energy Rate and the associated update
methodology to more accurately reflect the hourly, time-varying nature of cost
causation. No party has opposed the proposal by CEO to implement TOU energy
rates for Schedule 28. The Company has proposed a strawman of such rates in its
Surrebuttal, and parties in this docket also agreed to modified time periods in the
IPC-E-25-16 Settlement Agreement. CEO asks the Commission to direct the
Company to file a revision to Schedule 28 in which energy rates are updated with a
time-of-use pricing structure that reflects the same or similar new time periods as
the Schedule 19 TOU time periods stipulated in the IPC-E-25-16 General Rate Case
Settlement Agreement.38
2. In section 6.1 and any other relevant portions of the ESA should be amended to
make clear that any"additional transmission"costs not be limited to those needed
as traditional"Interconnection Facilities"and those costs should be covered by
Triton making additional upfront CIAC payments.39
3. The ESA should explicitly allow the ability to update the method used to determine
Energy and Demand charges.
3.2 Staff lead follow-on process
Issues listed in sections 2.1 through 2.6 above should be resolved within a follow-on
process setup within this docket. CEO recommends that Staff be directed to lead this
process.
The next GRC is an inappropriate forum for resolving such issues. GRCs can be used to
determine how much revenue should be collected from the FAB based on test year data
but they should not be relied upon to determine the specific method for calculating the
amount of revenue that should be collected from the FAB.
If the Commission approves the proposed settlement in GRC IPC-E-25-16 and the
Company opens a docket to address cost of service issues,that docket could address
some matters raised in this case. However, other matters are specific to large load
customers and should be addressed via a process specific to large load customers. CEO
requests that the Commission provide guidance on the means for addressing each of the
following matters:
• Guidelines regarding what constitutes a new Large Load Customer.
• When does anew large load customer transition from new to existing.
38 As described in IPC-E-24-44 White Surrebuttal, page15.
39 IPC-E-24-44 Hecker rebuttal page 6.
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 17

Clean Energy Opportunities for Idaho
• Which incremental costs caused by the new large load customer should be charged
to that customer, and how those costs should be measured.
• Guidelines for how customers that disproportionately cause upward pressure on
ROE and financing costs should pay for those impacts.
• Guidelines for No-Harm Scenario Analyses for large load customers so that the
Commission can adequately weigh the risks of harm to existing customers.
• Consideration of alternatives such as whether payments made in the form of self-
supply or CIAC could protect existing customers.
• The degree to which G&T infrastructure provide energy benefits and the means of
reflecting those in energy rates.
Respectfully submitted,
Courtney White Michael Heckler
Managing Director Policy Director
Clean Energy Opportunities for Idaho Clean Energy Opportunities for Idaho
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 18

CERTIFICATE OF SERVICE
I hereby certify that on this 2nd day of December, 2025, 1 delivered true and correct
copies of the foregoing CLOSING BRIEF to the following persons via the method of service
noted:
Electronic Mail Delivery (See Order No. 34602)
Idaho Public Utilities Commission
Monica Barrios-Sanchez
Commission Secretary
secretary(ilpuc.idaho.gov
Idaho PUC Staff
f
Chris Burdin
Deputy Attorney General
Idaho Public Utilities Commission
chris.burdin(@puc.idaho.gov
Idaho Power Company
Megan Goicoechea Allen
Donovan Walker
Connie Aschenbrenner
Grant Anderson
mgoicoecheaallenOidahopower.com
[e-mail]
caschenbrennerna idahopower.com
ganderson(@idahopower.com
dockets idahopower.com
Industrial Customers of Idaho Power, Inc.
Peter J. Richardson
Dr. Don Reading
[e-mail]
dreadingna mindspring.com
Idaho Irrigation Pumpers Association, Inc.
Eric L. Olsen
Lance Kaufman, Ph.D.
elo(a)echohawk.com
lance(a�aegisinsight.com
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 19

Micron Technology, Inc.
Austin Rueschhoff
Thorvald A. Nelson
Austin W. Jensen
Kristine A.K. Roach
Holland & Hart, LLP
darueschhoff0hollandhart.com
tnelson aphollandhart.com
awj [e-mail]
aclee(a)hollandhart.com
karoach(a)hollandhart.com
'U
Kelsey Jae
Attorney for CEO
IPC-E-24-44 Clean Energy Opportunities for Idaho's Closing Brief 20