20231128PAC to Staff 1-4.pdf

1407 W North Temple, Suite 330 Salt Lake City, Utah 84116
November 28, 2023 Jan Noriyuki Idaho Public Utilities Commission 472 W. Washington
Boise, ID 83702-5918 [e-mail] (C) RE: ID PAC-E-23-23
IPUC Set 1 (1-4) Please find enclosed Rocky Mountain Power’s Responses to IPUC 1st Set Data Requests 1-4. Also provided are Attachments IPUC 1 and 2. If you have any questions, please feel free to call me at [phone].
Sincerely, ____/s/____ Mark Alder Manager, Regulation Enclosures

RECEIVED
Tuesday, November 28, 2023 10:57:49 AM
IDAHO PUBLIC
UTILITIES COMMISSION
PAC-E-23-23 / Rocky Mountain Power November 28, 2023 IPUC Data Request 1
IPUC Data Request 1 Please provide all exhibits in Excel format with formulas intact and enabled.
Response to IPUC Data Request 1
Please refer to Attachment IPUC 1 which provides a copy of Exhibit No. 1 and Exhibit No. 2 in native Microsoft Excel format with formulas intact.

Note: In Exhibit No. 2, the base revenues and tax act adjustment (TAA) revenues are from the Company’s last general rate case (GRC), Case No. PAC-E-21-07. Recordholder: James Zhang / Deanna Fladstol

Sponsor: To Be Determined
PAC-E-23-23 / Rocky Mountain Power November 28, 2023 IPUC Data Request 2
IPUC Data Request 2 Please provide supporting documentation and/or workpapers for each month's amortization values from January 2022 to September 2023 presented in Exhibit
No. 1.
Response to IPUC Data Request 2
Please refer to Attachment IPUC 2 which provides the calculation of the
amortization values by month for January 2022 through December 2023. The amortization included in Attachment IPUC 2 represents a debit to a regulatory liability and a credit to income tax expense. The monthly amortization is derived via a ratio of year-to-date (YTD) pre-tax book income divided by a full
year forecast of pre-tax book income, as prescribed in Accounting Standards
Codification 740 (ASC 740).
Recordholder: Deanna Fladstol
Sponsor: To Be Determined
PAC-E-23-23 / Rocky Mountain Power November 28, 2023 IPUC Data Request 3
IPUC Data Request 3 Please provide work papers for calculations of October, November and December 2023 estimated amortization values.
Response to IPUC Data Request 3 Please refer to the Company’s response to IPUC Data Request 2.

Recordholder: Deanna Fladstol Sponsor: To Be Determined
PAC-E-23-23 / Rocky Mountain Power November 28, 2023 IPUC Data Request 4
IPUC Data Request 4 Monthly amortization amounts are based upon customer usage. Please clarify if the amortization ending balance through 2023 will total exactly $0. If so, please
explain how this will occur. If not, please explain how the Company proposes to
treat any unamortized balance. Response to IPUC Data Request 4

The Company requested amortization of the remaining excess deferred income tax (EDIT) balance of $8.5 million to be returned over two years beginning January 1, 2022. This ratemaking treatment was approved by way of an all-party stipulation in Case No. PAC-E-21-07. Consistent with the ratemaking treatment for all regulatory assets and liabilities, the Company’s amortization of the EDIT
balance was based on an annual amount. Any differences between the actual
Schedule 197 credits and ratemaking amortization are not tracked for future recovery or refund. As such, the Company assumes the accounting balance based on annual amortization used in ratemaking will be zero at the end of 2023.

Recordholder: Deanna Fladstol Sponsor: To Be Determined