20240826AVU to Staff 9-27.pdf

RECEIVED
Monday, August 26, 2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/19/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Xin Shane
TYPE: Production Request DEPARTMENT: EIM Settlement
REQUEST NO.: Staff- 009 TELEPHONE: [phone]
REQUEST:
Please respond to the following regarding the EIM benefits:
a. Please provide the dollar value of EIM benefits;
b. Please explain how the dollar values of EIM benefits are determined;
c. Please explain whether the methodology that determines EIM benefits is approved by the
Commission; and
d. Please provide evidence showing that EIM O&M included in the PCA does not exceed
EIM benefits.
RESPONSE:
Please see Avista's response Staff_PR_009C, which contains TRADE SECRET,
PROPRIETARY or CONFIDENTIAL information and exempt from public view and is
separately filed under IDAPA 31.01.01, Rule 067 and 233, and Section 9-340D, Idaho Code.
a. The total EIM benefit for the PCA review period, July 2023 to June 2024, is $18.6 million
system. Please refer to Staff PR 009C Confidential Attachment A for monthly detail.
b. The EIM benefit calculation process follows our internal method that was documented
back in 2022. Please refer to Staff_PR_009C Confidential Attachment B for detailed
information. This was provided to the Commission as part of a compliance filing in Case
No. AVU-E-22-11 on October 11, 2022. In that Case No., the Commission issued Order
No. 35543 stating the Company's October 11, 2022 report on its method for measuring
EIM benefits and how that method differs from CAISO's method complies with Order No.
35543.
c. See part b above.
d. The total EIM O&M for the PCA review period, July 2023 to June 2024, is approximately
$1.1 million system ($380,000 Idaho share), which is considerably less than the $18.6
million system provided in response to part a.

RECEIVED
Monday,August 26,2024
IDAHO PUBLIC
AVISTA CORPORATION UTILITIES COMMISSION
RESPONSE TO REQUEST FOR INFORMATION
JURISDICTION: IDAHO DATE PREPARED: 08/22/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Annette Brandon
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff-010 TELEPHONE: [phone]
REQUEST:
Please respond to the following regarding the CCA costs associated with surplus thermal
generation imported into Washington and subsequently sold to the market
as off-system sales ("off-system sales").
a) Please explain whether no-cost allowances for Washington's portion of the CCA costs
associated with the off-system sales are provided by the Washington Department of
Ecology.
b) Please confirm that Washington ratepayers pay for Washington's portion of CCA costs
associated with the off-system sales.
c) When the Company decides to make off-system sales, does it consider the CCA costs in
setting the prices of sold energy? Please describe the price-setting considerations in the
decision-making process.
d) Are the price-setting considerations for Idaho ratepayers different than those for
Washington ratepayers? Please explain.
RESPONSE:
Please see the following responses regarding surplus thermal generation:
a. The Department of Ecology has yet to confirm whether Avista will be held accountable to
the formula associated with WAC 173-441 (greenhouse gas reporting) or WAC 173-446
(climate commitment act).
b. In Washington State, electric ratepayers receive no-cost allowances. As noted in the
response to part(a), it is yet to be determined if off-system sales are covered in the true up
mechanism.
c. No, the Company does not include CCA allowance cost in its dispatch decisions, with the
exception of Idaho's portion (approximately 35%) of obligations related to Boulder Park.
d. No. The Company currently operates its electric operations on a system-level basis, with
the exception of Boulder Park.

RECEIVED
Monday,August 26,2024
IDAHO PUBLIC
AVISTA CORPORATION
UTILITIES COMMISSION
RESPONSE TO REQUEST FOR INFORMATION
JURISDICTION: IDAHO DATE PREPARED: 08/22/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Annette Brandon
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff-0I I TELEPHONE: [phone]
REQUEST:
Page 14 of Holland's Direct Testimony states that "Avista shareholders absorbed approximately
$700,000 in carbon expense for the sales benefit."Please respond to the following:
a. Please explain how the $700,000 is calculated and provide workpapers for the calculation.
b. Is the $700,000 based on the expenses associated with CCA allowance purchases,
regardless of whether the allowances are retired to meet the CCA target?
c. Is the $700,000 only associated with Idaho's allocation of off-system sales or does it
include Washington's allocation of the off-system sales? Please explain.
RESPONSE:
Please see Avista's response Staff_PR_011 C, which contains TRADE SECRET,
PROPRIETARY or CONFIDENTIAL information and exempt from public view and is
separately filed under IDAPA 31.01.01, Rule 067 and 233, and Section 9-340D, Idaho Code.
Please note, this portion of testimony was intended to illustrate the impact of the Idaho
Commission not allowing expenses associated with CCA to flow through the PCA. The$700,000
is illustrative in the amount of $700,000 for the 2023 calendar year. In accordance with
Commission directives, no expenses are included in the PCA in 2023 or in 2024.
Please see the following responses regarding surplus thermal generation:
a. Please see Staff_PR_011 C Confidential Attachment A for the calculation of the $700,000.
Please note this represents a rounded number, with the actual calculated number of
$662,437. The calculation is based on actual Boulder Park Generation(Idaho's share) and
the allowance end of month (EOM) market price. This generation is reflected on column
(H) of the attachment, prices are reflected in column(F).
b. Expense is calculated based on obli ag tion incurred during the month (in accordance with
matching principle). Please see response to part (a).
c. Please see the response to part(a).

RECEIVED
Monday,August 26,2024
IDAHO PUBLIC
AVISTA CORPORATION UTILITIES COMMISSION
RESPONSE TO REQUEST FOR INFORMATION
JURISDICTION: IDAHO DATE PREPARED: 08/22/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Annette Brandon
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff-012 TELEPHONE: [phone]
REQUEST:
Please respond to the following regarding CCA costs associated with Idaho's share of Boulder
Park generation:
a) Please explain the amount of CCA costs associated with Idaho's share of Boulder Park
generation;
b) Please explain whether the amount is absorbed by Avista shareholders; and
c) Is the amount based on the expenses associated with CCA allowance purchases,regardless
of whether the allowances are retired to meet the CCA target?Please explain.
RESPONSE:
Please note no expenses associated with the Climate Commitment Act is included in the PCA, in
accordance with Commission requirements.
a) Please see the Company's response to Staff PR 011.
b) In accordance with Commission guidance, any expense associated with CCA that would
otherwise be allocated to Idaho customers, is absorbed by Avista shareholders.
c) Please see the Company's response to Staff PR-0 11.

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/22/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Annette Brandon
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff-013 TELEPHONE: [phone]
REQUEST:
Please respond to the following regarding Boulder Park's dispatch costs:
a) Please explain whether CCA costs are considered in the dispatch costs of Boulder Park.
b) Please describe the cost-setting considerations in the dispatch decision-making process.
c) Are the dispatch costs of Boulder Park set differently for Idaho ratepayers than for
Washington ratepayers? Please explain.
d) Please explain which accounts captured those CCA costs associated with the dispatch of
Boulder Park.
e) Please provide the total amount of CCA costs with the dispatch of Boulder Park in this
PCA.
RESPONSE:
Parts (a)—(d): Please see the Company's response to Staff PR 011.
Part (e): No expenses associated with the Climate Commitment Act are included in the PCA, in
accordance with Commission requirements.

RECEIVED
Monday,August 26, 2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 014 TELEPHONE: [phone]
REQUEST:
Please explain whether only 90% of the Palouse Wind costs are included in the actual net power
costs. Please provide evidence to support your answer.
RESPONSE:
Yes, effective September 1, 2023 per the Company's last general rate case, 90% of the Palouse
Wind and Rattlesnake Flat Wind costs were included in the actual net power costs in accordance
with the Settlement Stipulation approved per Order 35156, Case Nos. AVU-E-23-01 and
AVU-G-23-01.
Please see Staff_PR_014 Attachment A for native (Excel) workpapers of the PDF version
available in the Company's Q4 2023 and Q2 2024 Quarterly PCA reports filed with the
Commission (see page 46 of the Q4 2023 report for July through December 2023 and page 40 of
the Q2 2024 report for January through June 2024). For ease of reference, the Company included
copies of the quarterly reports for this PCA review period in its original filing as well. The
workpaper shows on Excel rows 20 and 21 (Line Nos. 14 and 15) the monthly values of Palouse
Wind and Rattlesnake Flats. Excel row 41 represents the "Company Absorbed Wind," which is
10%of the overall amount of Palouse Wind and Rattlesnake Flats and is adjusted out of the overall
net power costs.

RECEIVED
Monday,August 26, 2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 015 TELEPHONE: [phone]
REQUEST:
Please explain whether only 90% of the Rattlesnake Flat Wind costs are included in the actual net
power costs and provide evidence to support your answer.
RESPONSE:
Please see the Company's response to Staff PRO 14.

RECEIVED
Monday,August 26, 2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 016 TELEPHONE: [phone]
REQUEST:
Please provide the workpapers that calculate the actual monthly costs of the Chelan contract.
RESPONSE:
The workpapers to calculate the actual monthly costs of the Chelan contract are included with
Avista's quarterly PCA report under the journal DJ480. For ease of reference, the workpapers
from March to June 2024 have been included as Staff_PR_016 Attachment A. These were also
provided to the Commission in the Company's Q 1 2024 Quarterly PCA report for February
through March 2024 (see pages 35 and 53, respectively) and Q2 2024 Quarterly PCA report for
April 2024 through June 2024 (see pages 16, 33, 51, respectively). The Company included copies
of the quarterly reports for this PCA review period in its original filing as well.

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 017 TELEPHONE: [phone]
REQUEST:
Please provide the workpapers that calculate the actual monthly costs of the Columbia Basin
Hydro ("CBH") contract.
RESPONSE:
Please see Staff_PR_017 Attachments A, B and C for the months of April 2024, May 2024 and
June 2024, respectively.

RECEIVED
Monday,August 26,2024
IDAHO PUBLIC
AVISTA CORPORATION UTILITIES COMMISSION
RESPONSE TO REQUEST FOR INFORMATION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 018 TELEPHONE: [phone]
REQUEST:
Please provide the workpapers that calculate the actual monthly costs of the CBH transmission.
RESPONSE:
The Company has not incurred incremental or additional transmission costs associated with the
CBH project during the PCA review period. The Company anticipates that incremental
transmission expenses will occur in 2025 when the larger resources within the CBH project deliver
power to Avista's system and additional purchased transmission will be necessary.

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 019 TELEPHONE: [phone]
REQUEST:
The actual purchased power expenses incurred by the Company are different than those reflected
in Account 555 in IPUC Deferral Analysis due to reasons such as the Stipulation in Case No.
AVU-E-23-01. Please provide a breakdown of the Company's actual purchased power expenses
by month and by seller and a breakdown of the actual Account 555 included in the IPUC Deferral
Analysis by month and by counterparty. Please reconcile the two and explain the cause for the
difference.
RESPONSE:
The workpaper provided in Schultz workpapers, tab named "Act-Ruth-Proposed"was developed
in close collaboration with Idaho Staff. The intent was to avoid duplication of work between
Company workpapers and Staff workpapers. Avista agreed to use Staff s workpapers in its filings
in the manner which best conforms to Staff s needs.
Actual purchased power expense, reflected in account 555 Purchased Power, is summarized by
month and by counterparty in the quarterly filings. The Company included copies of the quarterly
reports for this PCA review period in its original filing as well. For ease of reference, the native
(excel) workpapers for the PCA review period are provided in the Company's response to
Staff_PR_014 Attachment A. In reconciling the information previously provided to Staff, see
Staff_PR 014 Attachment A,Excel row 24(Line No. 18)and Schultz workpaper Excel row 18 for
the specific months, which shows only an immaterial variance by month(+/- $1) due to rounding.
Please see the Company's response to Staff_PR_025 for the Company's Generation and Purchase
workpaper for details by month and by counterparty. Please note the Generation and Purchase
reflects the total amount of purchases, and does not include any adjustments made to the PCA
calculation to conform with general rate case or contract approvals by the Idaho Commission.

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 020 TELEPHONE: [phone]
REQUEST:
The actual transmission expenses incurred by the Company are different than those reflected in
Account 565 in IPUC Deferral Analysis due to reasons such as the Stipulation in Case No.
AVU-E-23-01. Please provide a breakdown of the Company's actual transmission expenses by
month and by transmission provider and a breakdown of the actual Account 565 included in the
IPUC Deferral Analysis by month and by counterparty. Please reconcile the two and explain the
cause for the difference.
RESPONSE:
Both referenced workpapers (July 2023 —June 2024 Variance Analysis and Schultz workpapers,
tab named"Act-Auth-Proposed")provide an actual expense amount of$18,948,0501 for the PCA
review period and are in agreement on a month-by-month basis.
The Company is providing the detail of 565 Transmission Expense in two files. Please see
PC—DR_020 Attachment A for July 2023 through December 2023 and PC—DR_020 Attachment B
for January 2024 through June 2024.
'Expressed in thousands in"July 2023—June 2024 Variance Analysis.xls".

RECEIVED
Monday,August 26,2024
IDAHO PUBLIC
AVISTA CORPORATION UTILITIES COMMISSION
RESPONSE TO REQUEST FOR INFORMATION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 021 TELEPHONE: [phone]
REQUEST:
Please define Cost Variance in Table No. 1, on page 16 of Holland's Direct Testimony. Also,
please explain why the sum of all Cost Variances is equal to the Total Variance.
RESPONSE:
The "cost variance" represents the price/quantity variance when comparing the actual values to
authorized as recorded to the general ledger. Said differently, it represents the difference between
actual costs and authorized costs. See also page 15 of Witness Holland's Direct Testimony filed in
this case for additional descriptions of this variance.
Costs associated with the variance generation types (hydro, wind, thermal, gas) are further
analyzed by the "generation variance," which essentially reallocates the cost variance to the
applicable resource. This reallocation is not a change in overall cost, rather, it serves to further
provide explanation of how each resource contributed towards meeting load requirements. Since
the generation variance has a net zero impact, the "total variance" on a net basis will equal the
"cost variance".

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 022 TELEPHONE: [phone]
REQUEST:
Please define Generation Variance in Table No. 1, on page 16 of Holland's Direct Testimony.
Also, please explain why the sum of all Generation Variances is zero.
RESPONSE:
Please see the Company's response to Staff PR_021 and also pages 15-16 of Witness Holland's
Direct Testimony filed in this case.

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 023 TELEPHONE: [phone]
REQUEST:
According to the Clearwater Agreement,net revenue from the sale of Clearwater generated RECs
will be split between the Company(10%)and Clearwater(90%). Please provide evidence showing
that the amounts of revenue reflected in Line "456380 ED ID — Sch 25P REC Revenue" in the
IPUC Deferral Analysis corresponds to 10% of the net revenue from the sale of Clearwater
generated RECs.
RESPONSE:
Please see Avista's response Staff_PR_023C, which contains TRADE SECRET,
PROPRIETARY or CONFIDENTIAL information and exempt from public view and is
separately filed under IDAPA 31.01.01, Rule 067 and 233, and Section 9-340D, Idaho Code.
FERC Account 456380 ED.ID is recorded within Avista's accounting system with the accounting
name "Other Electric Rev-Clearwater RECS"which represents the 10% of the REC split.
To support this and provide evidence as requested, please see Staff_PR_023C Confidential
Attachment A for the June 2024 monthly workpaper, calculating the 10% REC value of
$95,186.04. This amount agrees to the corresponding value within the IPUC Deferral Analysis
(Schultz workpapers, tab named"Act-Auth-Proposed", cell N60).

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 024 TELEPHONE: [phone]
REQUEST:
Please respond to the following regarding Line "456030 ED ID Sch 25 P Transmission" in the
IPUC Deferral Analysis:
a. Please explain what Line "456030 ED ID-Sch 25 P Transmission"represents;
b. Please explain how the values on the Line "456030 ED ID-Sch 25 P Transmission" are
determined and provide workpapers that calculate the values;
c. Please explain how the MWhs used in the calculation of actual purchase power expenses
are determined;
d. Please explain why the value remains at the same level ($13,750) from July 2023 through
February of 2024;
e. Please explain why the value starts changing from March of 2024 on; and
f. Please explain why the value varies from month-to-month after March of 2024.
RESPONSE:
Please see Avista's response Staff_PR_024C, which contains TRADE SECRET,
PROPRIETARY or CONFIDENTIAL information and exempt from public view and is
separately filed under IDAPA 31.01.01, Rule 067 and 233, and Section 9-340D, Idaho Code.
a. This line represents the transmission purchased for the Morgan Stanley REC deal.
b. The transmission value assigned to 456030 ED.ID is calculated as 10 percent of the
transmission purchased by Avista to facilitate the deal with Morgan Stanley (bundled
energy and REC's generated by Clearwater Paper)that is Avista's share. Clearwater Paper
is responsible for 90 percent of the purchased transmission.
c. The MWh value is based on the actual metered energy used by Clearwater Paper. The costs
associated with Morgan Stanley are a flat monthly amount and the remainder is charged to
Clearwater Paper.
d. The value is based on the agreed upon reservation values in MWh. In 2024, Clearwater's
transmission reservations had more variability between service types (Monthly Firm,
Weekly Firm, Daily Firm)which is reflected in the resulting monthly expenses. Please see
Staff PR_024C Confidential Attachment A for calendar 2023 and Staff_PR_024C
Confidential Attachment B for the January through July 2024 (YTD) volumes and totals
associated with each transmission service.
e. See part d. above.
f. See part d. above.

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 025 TELEPHONE: [phone]
REQUEST:
If Line"456030 ED ID-Sch 25 P Transmission"does not represent the deferral of purchase power
expenses the Company pays Clearwater, please explain where such a deferral is located in the
IPUC Deferral Analysis. Also, please provide workpapers that calculate such a deferral. Lastly,
please explain how the MWhs used in the calculation of actual purchase power expenses of
Clearwater are determined.
RESPONSE:
Account 456030 ED.ID represents the transmission costs charged to Clearwater to deliver their
generation to Avista's system. Purchases associated with the Clearwater Paper PPA are recorded
in FERC Account 555380 and are included as part of the overall 555 Purchased Power total.
Please see Staff_PR_025 Attachment A for calendar 2023 and Staff_PR_025 Attachment B for the
January through June 2024 MWh volumes and resulting costs for the Clearwater agreement.

RECEIVED
Monday,August 26,2024
IDAHO PUBLIC
AVISTA CORPORATION UTILITIES COMMISSION
RESPONSE TO REQUEST FOR INFORMATION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff- 026 TELEPHONE: [phone]
REQUEST:
Please provide Clearwater's amount of generation and load by month during the deferral period.
RESPONSE:
Please see the Company's response to Staff PR 025.

RECEIVED
Monday,August 26,2024
AVISTA CORPORATION IDAHO PUBLIC
RESPONSE TO REQUEST FOR INFORMATION UTILITIES COMMISSION
JURISDICTION: IDAHO DATE PREPARED: 08/23/2024
CASE NO: AVU-E-24-07 WITNESS: Kevin Holland
REQUESTER: IPUC RESPONDER: Ryan Finesilver
TYPE: Production Request DEPARTMENT: Energy Supply
REQUEST NO.: Staff—027 TELEPHONE: [phone]
REQUEST:
Please provide the forced and unforced downtime that lasted over 24 hours for each of the
Company's generation plants during the deferral period and provide the causes of each downtime.
RESPONSE:
Please see Avista's response Staff_PR_027C, which contains TRADE SECRET,
PROPRIETARY or CONFIDENTIAL information and exempt from public view and is
separately filed under IDAPA 31.01.01, Rule 067 and 233, and Section 9-340D, Idaho Code.
Please see the Company's response to Staff_PR_005C for the requested information pertaining to
forced outages. For planned and maintenance outages, Avista has provided two spreadsheets, one
for July 1, 2023 through December 31, 2023 (Staff_PR_027C Confidential Attachment A), and
one for January 1, 2024 through June 30, 2024 (Staff PR 027C Confidential Attachment B).
For Colstrip,there was one planned outage on Unit 3 in September of 2023 to replace a temporary
exciter system with a refurbished exciter. There were two outages on Unit 4. One was a decision
to repair a tube leak. The unit was shut down to affect the repair in advance of expected extreme
cold weather. The second outage was the planned overhaul. Please see Staff_PR_027C
Confidential Attachment C for Unit 3 and Staff PR 027C Confidential Attachment D for Unit 4.