20230316INT to Staff - Response to No. 116-117.pdf

RESPONSE TO THE NINTH PRODUCTION REQUEST OF COMMISSION STAFF PAGE 1 OF 3
Preston N. Carter, ISB No. 8462
Blake W. Ringer, ISB No. 11223
Givens Pursley LLP
601 W. Bannock St.
Boise, Idaho 83702
Telephone: [phone]
Facsimile: [phone]
[e-mail]
[e-mail]

Attorneys for Intermountain Gas Company

BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION

IN THE MATTER OF THE APPLICATION OF
INTERMOUNTAIN GAS COMPANY FOR
AUTHORITY TO INCREASE ITS RATES AND
CHARGES FOR NATURAL GAS SERVICE IN
THE STATE OF IDAHO

Case No. INT-G-22-07

INTERMOUNTAIN GAS COMPANY’S
RESPONSES TO THE NINTH PRODUCTION
REQUEST OF THE COMMISSION STAFF

In response to the Ninth Production Request of the Commission Staff to Intermountain
Gas Company dated March 9, 2023, Intermountain Gas Company, (“Intermountain,”
“Applicant,” or “Company”), submits the following responses. Responsive documents are
available for download using the link provided in the accompanying email.
DATED: March 16, 2023.

GIVENS PURSLEY LLP

Preston N. Carter
Attorney for Intermountain Gas Company
RECEIVED
Thursday, March 16, 2023 2:24:02 PM
IDAHO PUBLIC
UTILITIES COMMISSION
RESPONSE TO THE NINTH PRODUCTION REQUEST OF COMMISSION STAFF PAGE 2 OF 3
CERTIFICATE OF SERVICE
I certify that on March 16, 2023, a true and correct copy of the foregoing was served
upon all parties of record in this proceeding via electronic mail as indicated below:

Commission Staff Via Electronic Mail
Jan Noriyuki, Commission Secretary
Idaho Public Utilities Commission
11331 W. Chinden Blvd., Bldg. 8, Suite 201-A
Boise, ID 83714

[e-mail]
Dayn Hardie
Deputy Attorney General
Idaho Public Utilities Commission
11331 W. Chinden Blvd., Bldg. 8, Suite 201-A
Boise, ID 83714
[e-mail]

Chad M. Stokes
Cable Huston LLP
1455 SW Broadway, Ste. 1500
Portland, OR 97201
Attorneys for Alliance of Western Energy
Consumers
[e-mail]

Marie Callaway Kellner
710 N. 6th Street
Boise, ID 83702
Attorneys for Idaho Conservation League
[e-mail]

Brad Heusinkveld
Idaho Conservation League, Energy Assoc.
710 N. 6th Street
Boise, ID 83702
[e-mail]

Darrell Early
Ed Jewell
Deputy City Attorney
Boise City Attorney’s Office
150 N. Capitol Blvd.
PO Box 500
Boise, ID 83701-0500
[e-mail]
[e-mail]
[e-mail]

RESPONSE TO THE NINTH PRODUCTION REQUEST OF COMMISSION STAFF PAGE 3 OF 3

Wil Gehl
Energy Program Manager
Boise City Dept. of Public Works
150 N. Capitol Blvd.
PO Box 500
Boise, ID 83701-0500
[e-mail]

Preston N. Carter

INTERMOUNTAIN GAS COMPANY
CASE INT-G-22-07
NINTH PRODUCTION REQUEST OF THE COMMISSION STAFF
Preparer/Sponsoring Witness: Min Park/ Lori
Blattner
REQUEST NO. 116:
Please provide the data used as inputs, the Eviews workfiles, and workpapers supporting
the Company’s Weather Normalization adjustments updated to include the Company’s actual
2022 calendar year information.
RESPONSE NO. 116:
The Company updated the weather normalization variables to include data through
December 2022. The variable file is included as “RFP 116 Import Workbook 2022 Dec
Update.xls”. The Company then used the updated variables to calculate updates to the filed
weather normalization model as well as several variations discussed by the Company and Staff.
The eViews workfiles are included as “RFP 116 RS_2022_MODELS.wf1” and “RFP 116
GS_2022_MODELS.wf1”. A printout of the resulting models and residual graphs is included as
“RFP 116 Weather Normalization Models 2022 Dec Update.pdf.”. Because there was not much
difference in the final revenue requirement result from any of the six update models shown on
“RFP 116 Weather Normalization Models 2022 Dec Update.pdf”, the Company chose to use the
same model structure as originally filed, updated with actuals through Dec 2022, in the updated
testimony of Ms. Blattner.
INT-G-22-07
IPUC DR 116
Page 1 of 1
INTERMOUNTAIN GAS COMPANY
CASE INT-G-22-07
NINTH PRODUCTION REQUEST OF THE COMMISSION STAFF
Preparer/Sponsoring Witness: Chris Mickelson / Ron Amen
REQUEST NO. 117:
Please provide the data used as inputs and workpapers supporting the Company’s Cost of
Service Study and Load study updated to include the Company’s actual 2022 calendar year
information. When applicable, please provide workpapers in electronic format with links intact
and formulae enabled.
RESPONSE NO. 117:
Please see the Company’s filing on March 9, 2023, for Mr. Amen’s updated direct
testimony, exhibits, and workpapers that provided the Company’s cost of service study updated
to actual 2022 calendar year information. Please refer to Attachments to this response for
additional workpapers updated with customer related information.
The Company’s load study uses both daily (via AMI where available) and monthly usage
data by rate class from January 2019 through July 2022 to perform regression analyses, as
described in Mr. Amen’s direct testimony, Section IV, Load Study and Analysis. The regression
results were extrapolated from the Monthly system peak load sendout data to the average test
year number of customers, updated through December 2022, for each of the Core classes, RS and
GS. The resulting statistical properties from the extensive regression analyses was sufficient to
conclude that the 3 ½ years of usage data was sufficient and did not require updating to include
the Company’s last six months of actual 2022 calendar year customer usage information.
RFP 117 Attachment A:Supplemental_External_Meters_M&R (MTRS_M&R)
RFP 117 Attachment B:Supplemental_External_SALES_TRANS
RFP 117 Attachment C:Supplemental_External_Services (SERV)
INT-G-22-07
IPUC DR 117
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RFP 117 Attachment D: Supplemental_IGC Load Study Workpaper - Dec 2022
Actuals.xlsx
INT-G-22-07
IPUC DR 117
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