20210524IPC to Staff 1-12.pdf

DONOVAN E. WALKER
Lead Counsel
[e-mail]

May 24, 2021

VIA ELECTRONIC MAIL

Jan Noriyuki, Secretary
Idaho Public Utilities Commission
11331 West Chinden Blvd., Building 8
Suite 201-A
Boise, Idaho 83714

Re: Case No. IPC-E-21-09
Idaho Power Company’s Application for Capacity Deficiency To Be Utilized
For Avoided Cost Calculations

Dear Ms. Noriyuki:

Attached for electronic filing is Idaho Power Company’s Response to the First
Production Requests of the Commission Staff in the above entitled matter.

Please handle the confidential information in accordance with the Protective
Agreement executed in this matter.

If you have any questions about the attached documents, please do not hesitate
to contact me.

Very truly yours,
Donovan E. Walker

DEW:cld
Enclosures
RECEIVED
2021 May 24, PM 4:13
IDAHO PUBLIC
UTILITIES COMMISSION
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 1
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]
[e-mail]

Attorney for Idaho Power Company

BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION

IN THE MATTER OF IDAHO POWER
COMPANY’S APPLICATION FOR
APPROVAL OF THE CAPACITY
DEFICIENCY TO BE UTILIZED FOR
AVOIDED COST CALCULATIONS.
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CASE NO. IPC-E-21-09

IDAHO POWER COMPANY’S
RESPONSE TO THE FIRST
PRODUCTION REQUEST OF
THE COMMISSION STAFF

COMES NOW, Idaho Power Company (“Idaho Power” or “Company”), and in
response to the First Production Request of the Commission Staff to Idaho Power
Company dated May 3, 2021, herewith submits the following information:

RECEIVED
2021 May 24, PM 4:13
IDAHO PUBLIC
UTILITIES COMMISSION
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 2
REQUEST NO. 1: Please provide Attachment 1 in Excel format with all formulae
intact.
RESPONSE TO REQUEST NO. 1: Please see the attached Excel file.
The response to this Request is sponsored by Michael Darrington, Energy
Contracts Leader of Idaho Power Company.

IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 3
REQUEST NO. 2: Please describe what is included in “Existing EE” in the Load
and Resource Balance and whether it includes all cost-effective EE yet to be implemented
or if it only includes EE already implemented. Please provide the source of the data.
RESPONSE TO REQUEST NO. 2: “Existing EE” in the Load and Resource
Balance worksheet is the Achievable Economic Energy Efficiency Potential, which
includes existing and future energy efficiency. It includes all energy efficiency measures
determined to be cost effective from the Utility Cost Test (UCT) perspective, regardless
of whether they are in an existing program. This forecast of energy efficiency potential is
from the Energy Efficiency Potential Study conducted in 2020 by Applied Energy Group.
The response to this Request is sponsored by Jared Hansen, Resource Planning
Leader of Idaho Power Company.

IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 4
REQUEST NO. 3: Please define “non-forecasted trended EE” and explain why its
value is zero throughout the IRP planning horizon. Please provide the source of the data.
RESPONSE TO REQUEST NO. 3: “Non-forecasted trended EE” refers to any
energy efficiency (“EE”) that was not already included in the load forecast or in IRP
portfolios. For information on what kind of EE was included in the load forecast, please
refer to Data Request No. 2. This value is zero throughout the planning horizon because
all other EE programs identified as cost effective were already included in the Load &
Resource Balance workbook. For more information on how EE programs were modeled
and analyzed, please see Chapter 5 of the Second Amended 2019 IRP.
The response to this Request is sponsored by Jared Hansen, Resource Planning
Leader of Idaho Power Company.

IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 5
REQUEST NO. 4: Please provide the exit dates assumed for each unit of the
Bridger coal plant and for Valmy Unit #2 and explain the basis that was used for
determining the dates.
RESPONSE TO REQUEST NO. 4: The exit dates for the Bridger coal plant units
and Valmy Unit 2 are from the Preferred Portfolio of the Second Amended 2019 IRP.
Valmy Unit 2 has an assumed exit date of year-end 2022. Exits for the four Bridger units
are assumed at year-end 2022, 2026, 2028, and 2030.
The response to this Request is sponsored by Jared Hansen, Resource Planning
Leader of Idaho Power Company.

IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 6
REQUEST NO. 5: Please provide the amount of market purchases that are
assumed from the Southwest Transmission Pathway associated with the retirement of
the Valmy coal plant? Please provide rationale for the assumptions and explain how the
assumptions are reflected in the Load and Resource Balance.
RESPONSE TO REQUEST NO. 5: Energy from the North Valmy coal plant is
scheduled to Idaho Power on the Valmy to Midpoint 345 kV line. Exit from each North
Valmy coal plant was assumed to make available approximately 130 MW of transmission
capacity for purchases from Southwest markets. The assumption from the Second
Amended 2019 IRP was that generation from North Valmy could be replaced by market
purchases from Southern market hubs. As stated on page 18 of the 2nd Amended 2019
IRP, (under the Valmy Unit 2 Exit Date section) and on pages 77-78 (under the Nevada
Transmission without North Valmy section), these assumptions require future testing.
These assumptions are shown in the Load & Resource Balance worksheet as an
increase in Market Purchases as the Valmy units are exited for June through September
of each year.
The response to this Request is sponsored by Jared Hansen, Resource Planning
Leader of Idaho Power Company.

IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 7
REQUEST NO. 6: Please explain how the amount of deficit or surplus is
determined in the Load and Resource Balance, especially with respect to the resolution
of time. In addition, please answer the following:
a. Are all hours examined or are there set times of the day that are examined
for each month? Please explain.
b. If all hours are examined, how is the information converted to monthly data?
c. Does the contribution at peak for different resources use the same time
periods as above? Please explain.
d. What data is used to determine the contribution of peak for wind and solar
in the Load and Resource Balance?
e. Please explain why PURPA solar capacity is zero in winter months
(December, January, and February).
RESPONSE TO REQUEST NO. 6: The deficit or surplus is determined by
subtracting the monthly peak forecasted demand, which includes the effect of energy
efficiency and demand response, from the sum of available generation resources, power
purchase agreements, and transmission capacity available for market purchases.
a. The forecasted system peak hour from each month was examined
b. All hours were not examined in the Load & Resource Balance
c. Yes, contributions from resources reflect their anticipated capability for the
system peak hours.
d. The contribution to peak for solar was calculated using the 8760-Method
developed by the National Renewable Energy Laboratory using 2017 and 2018
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 8
data. The contribution to peak for wind was calculated using a capacity factor
method based on 2011-2013 data.
e. For winter months, the system peak hour occurs in the morning before sunrise.
The response to this Request is sponsored by Jared Hansen, Resource Planning
Leader of Idaho Power Company.

IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 9
REQUEST NO. 7: Have there been any updates to PURPA contracts, such as
terminations or additions since the development of this Load and Resource Balance in
the 2019 IRP? Please list all the updates.
RESPONSE TO REQUEST NO. 7: Since the development of the Load &
Resource Balance in the2019 IRP, the Energy Sales Agreements (“ESA”) applicable to
the following PURPA Qualifying Facilities (“QF”) have been terminated or expired without
a replacement ESA:
Project
Resource
Type
Nameplate
Capacity (MW)
Bettencourt Dry Creek Biofactory Biomass 2.25
Big Sky West Dairy Digester Biomass 1.5
Double A Digester Biomass 4.5
Rock Creek Dairy Biomass 4
Kasel and Witherspoon Hydro 0.9

Idaho Power has added the following QFs since the development of the Load & Resource
Balance in the 2019 IRP:
Project
Resource
Type
Nameplate
Capacity (MW)
Durkee Solar Solar 3
Coleman Hydro Hydro 0.8

The response to this Request is sponsored by Michael Darrington, Energy
Contracts Leader of Idaho Power Company.
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 10
REQUEST NO. 8: Have there been any updates to power purchase agreements,
such as terminations or additions since the development of this Load and Resource
Balance in the 2019 IRP? Please list all the updates.
RESPONSE TO REQUEST NO. 8: There have been no updates or changes to
power purchase agreements.
The response to this Request is sponsored by Michael Darrington, Energy
Contracts Leader of Idaho Power Company.
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 11
REQUEST NO. 9: Please explain how Market Purchases’ contribution to peak is
determined. In the explanation, please include whether market availability and
transmission capacity were considered. Also, please provide a breakdown of market
availability by market hub, if available, in Excel format with formulae intact.
RESPONSE TO REQUEST NO. 9: Market Purchases are assumed to fully
contribute to peak. Idaho Power reserves portions of its transmission capacity to import
energy for load service (network set-aside). The Market Purchases’ contribution to peak
is determined based on firm transmission capacity that is available/set-aside and it is
assumed there will be market availability to fully utilize the associated transmission
capacity to meet peak needs.
Please see the attached Excel file for a breakdown of available transmission
capacity assumed in the Load & Resource Balance workbook.
The response to this Request is sponsored by Jared Hansen, Resource Planning
Leader of Idaho Power Company.
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 12
REQUEST NO. 10: Does the Company have interruptible load contracts included
in the Load and Resource Balance? If so, please describe each contract. Also, please
provide the following:
a. Explain how interruptible load contracts are included in the Load and
Resource Balance.
b. Provide the amount of capacity contribution in each year.
c. Explain if interruptible load contracts are assumed to be renewed in the
Load and Resource Balance after contract expiration.
d. Please explain whether their values were considered for load when
calculating the planning margin.
RESPONSE TO REQUEST NO. 10: Idaho Power does not currently have
interruptible load contracts. As a result, none are included in the Load & Resource
Balance.
The response to this Request is sponsored by Jared Hansen, Resource Planning
Leader of Idaho Power Company.
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 13
REQUEST NO. 11: Is the load forecast included in the Application the latest
information available? If not, please provide the latest load forecast and explain causes
for any difference from the amounts included in the Application. In the explanation, please
include how the latest load forecast reflects impacts of the pandemic.
RESPONSE TO REQUEST NO. 11: No, the load forecast included in the
Application is not the latest information available. The latest load forecast is provided in
the attached Confidential Excel file.
The differences between the latest load forecast and the amounts included in the
Application were caused by numerous factors, including: more recent economic forecast
drivers from Moody’s and Woods and Poole, updated electricity and natural gas price
forecasts, new sales forecasts provided by special contract customers, new residential
SAE input files from Itron, and updates of numerous regression models. These factors,
and others, are all considered part of Idaho Power’s annual forecasting process and
update.
The latest load forecast reflects the impacts of the COVID-19 pandemic
(“pandemic”) as was known and evident in the summer of 2020 when the forecast was
prepared. These pandemic impacts are described in more detail below.
The Company did adjust its Residential load forecast as a result of the pandemic.
Observed data during the affected billing months in 2020 demonstrated an increase in
usage in the Residential sector due to pandemic impacts. Fittingly, the Residential
forecast was increased for the short-term only, based on the limited historical data (April
2020 through July 2020) available for observation and absent a generally accepted
estimate of the duration of the pandemic.
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 14
Commercial and Industrial (C/I) forecast models are built on a long-term annual
basis. The energy impact in the customer classes in regard to the pandemic response
became evident in variance tracking beginning in spring of 2020. By virtue of the models’
annual structure, this data was not directly available for inclusion into the history. While
many of the economic inputs from third-party providers did have assumptions for future
impacts of lockdown behavior, not all models could utilize this input, particularly the
smaller commercial customer class models.
To accurately forecast the impact, the Company used short-term analysis of
monthly and daily usage to adjust the first year of the forecast (2020) to establish historical
trended end-of-year forecasts. These short-term forecasts were compared to model
output to serve as the basis for adjustment. For Industrial and Large Commercial
customers, the forecast years 2021 and 2022 were adjusted downward based on
observed results. For the remaining commercial customer class, downward adjustments
were applied for the years 2021 to 2025.
Any differences to the forecast for irrigation sales is due to the annual update of
the irrigation sales forecast regression. The model is discussed in Appendix A—Sales
and Load Forecast to the Second Amended 2019 Integrated Resource Plan. The updated
dependent and independent variables, coefficients, regression time period, etc., resulted
in forecast differences. The Company did not include adjustments or changes to its
irrigation load forecast as a result of the pandemic. Due to the regular variability of the
irrigation class relative to other customer classes, the Company did not find it necessary
to include an adjustment.
No additional pandemic-related adjustments or changes were made by the
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 15
Company to the load forecasts for Special Contracts from what was submitted to the
Company. Each year, an “Annual Request for Load Forecast Information” letter is sent to
each of the Company’s Special Contract customers: Micron Technology, Simplot
Fertilizer, and the Idaho National Laboratory. In 2020, the letters that were sent requested
that their individual load forecasts should “assume that all attached information is
reflective of any near-term demand and energy impacts attributable to recent changes in
economic conditions.” Accordingly, the forecast figures provided are assumed to reflect
pandemic impacts to the best knowledge of the Special Contract customer at that time.
Any differences to the forecasts for Special Contracts were due to the updated Annual
Requests provided by each Special Contract customer.
The response to this Request is sponsored by Jordan Prassinos, Load Research
and Forecasting Manager of Idaho Power Company.
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 16
REQUEST NO. 12: Please explain how net-metering generation is considered in
the Load and Resource Balance and answer the following questions.
a. How is the capacity contribution of net-metering generation determined?
Please provide workpapers that calculate the capacity contribution with formulae intact.
b. Please explain if the capacity contribution comes from both existing net-
metering customers and/or forecasted net-metering customers.
c. Are existing net-metering customers assumed to continue throughout the
IRP planning horizon once included in the Load and Resource Balance, and are the levels
of their capacity contribution expected to change over time? Please explain.
RESPONSE TO REQUEST NO. 12: As explained in the On-Site Generation
section of Appendix A—Sales and Load Forecast of the Second Amended 2019 IRP, “the
long-term sales forecast was adjusted downward to reflect the impact of the increase in
the number of customers with on-site generation, specifically solar, connecting to our
system.”
Schedules 6, 8, and 84 (net-metering) customer usage is compared to usage prior
to identified customers becoming a net-metering customer. The resulting decrement in
average monthly sales per customer (in kWh) is then multiplied by forecasts of the
Schedule 6, 8, and 84 residential and commercial customer counts to estimate the future
energy impact on the sales forecast. The forecast of net-metering customers serves as a
function of historical trends and current policy considerations.
The forecast of net-metering customers multiplied by the estimated sales impact
per customer results in a monthly downward adjustment to the sales forecast for each
class. At the end of the forecast period (2038), the annual residential sales forecast
IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 17
reduction was about 38 aMW, and the commercial reduction was less than 4 aMW.
Please see the attached Excel file containing the net-metering customer forecasts and
associated sales impacts for residential and commercial net-metering.
a. The monthly load forecast is reduced by the projected net-metering impacts
over the forecast period through the process identified above. The result is a primary
input to the monthly peak demand forecast regression models. By nature of the process,
the peak demands are lower because of the decrement to average load that is identified.
The resulting expected case load forecast and expected case peak forecast are
considered in the Load & Resource Balance. There are no specific workpapers that
calculate the system capacity contribution as it is a function of the overall monthly sales
and load forecast process. The attached Excel file calculates the average capacity
forecast.
b. The average capacity contribution comes from both existing net-metering
customers (see c below) and forecasted net-metering customers (see above).
c. Yes, existing net-metering customers are assumed to continue throughout
the IRP planning horizon and are included in the Load and Resource Balance. The levels
of their average capacity contribution are expected to change over time due to net-
metering’s decremental impact on historical sales and are assessed annually.
The response to this Request is sponsored by Jordan Prassinos, Load Research
and Forecasting Manager of Idaho Power Company.

IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 18
Respectfully submitted this 24th day of May 2021.

DONOVAN E. WALKER
Attorney for Idaho Power Company

IDAHO POWER COMPANY’S RESPONSE TO THE FIRST PRODUCTION REQUESTS OF THE
COMMISSION STAFF - 19
CERTIFICATE OF SERVICE

I HEREBY CERTIFY that on this 24th day of May 2021, I served a true and correct
copy of the within and foregoing IDAHO POWER COMPANY’S RESPONSE TO THE
FIRST PRODUCTION REQUESTS OF THE COMMISSION STAFF upon the following
named parties by the method indicated below, and addressed to the following:

Matt Hunter
Deputy Attorney General
Idaho Public Utilities Commission
Po Box 83720
Boise, Idaho 83720-0074

Hand Delivered
U.S. Mail
Overnight Mail
FAX
X Email Matt Hunter
[e-mail]

________________________________
Christy Davenport, Legal Assistant