202305012023 IRP Sensitivity Studies.pdf

1407 W. North Temple, Suite 330
Salt Lake City, UT 84116
May 1, 2023
VIA ELECTRONIC FILING AND OVERNIGHT DELIVERY
Jan Noriyuki
Commission Secretary Idaho Public Utilities Commission 11331 W Chinden Blvd Building 8 Suite 201A
Boise, Idaho, 83714
RE: CASE NO. PAC-E-23-10 - PACIFICORP’S APPLICATION FOR ACKNOWLEDGEMENT OF THE 2023 INTEGRATED RESOURCE PLAN
Dear Ms. Noriyuki:
On March 31, 2023, PacifiCorp d/b/a Pacific Power (PacifiCorp or Company) filed its 2023 Integrated Resource Plan (2023 IRP) in the above-referenced docket. PacifiCorp is now supplementing its filing with results of its 2023 IRP sensitivity studies.

The Company is also providing public and confidential electronic workpapers that contain supporting information for the analyses included in the 2023 IRP. Informal inquiries, including requests to receive a copy of the 2023 IRP filing or non-disclosure
agreement, may be directed to Mark Alder, Idaho Regulatory Affairs Manager, at (801) 220-
2313. Sincerely,

Joelle Steward Senior Vice President of Regulation and Customer Solutions

Enclosures cc: Ed Schriever, Idaho Governor’s Office (without enclosures) Brad Heusinkveld, Idaho Conservation League (without enclosures)
Ryan Adelman, Idaho Power Company (without enclosures)
Teri Carlock, Idaho Public Utilities Commission staff (without enclosures) Thomas J. Budge, (Bayer) (without enclosures) Nancy Kelly, Western Resource Advocates (without enclosures)
RECEIVED
2023 May 1, 4:16PM
IDAHO PUBLIC
UTILITIES COMMISSION

2023 INTEGRATED RESOURCE PLAN
SENSITIVITY MODELING RESULTS

PACIFICORP

PACIFICORP – 2023 IRP SENSITIVITY – MODELING RESULTS
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TABLE OF CONTENTS

TABLE OF CONTENTS ...................................................................................... i
INDEX OF TABLES ............................................................................................. i
INDEX OF FIGURES ........................................................................................... i
ADDITIONAL SENSITIVITY ANALYSIS ...................................................................... 1
P-MM SENSITIVITY CASES ............................................................................................................................ 1
HIGH LOAD GROWTH SENSITIVITY (S-01) ...................................................................................... 1
LOW LOAD GROWTH SENSITIVITY (S-02) ........................................................................................ 2
1-IN-20 LOAD GROWTH SENSITIVITY (S-03) ................................................................................... 3
HIGH PRIVATE GENERATION SENSITIVITY (S-04) ............................................................................ 4
LOW PRIVATE GENERATION SENSITIVITY (S-05) ............................................................................. 5
BUSINESS PLAN SENSITIVITY (S-06) ................................................................................................................... 6

INDEX OF TABLES

TABLE S.1 – SUMMARY OF P-MM SENSITIVITY CASES............................................... 1
TABLE S.2 – RISK-ADJUSTED PVRR (BENEFIT)/COST OF S-01 VS. P-MM ................. 2
TABLE S.3 – RISK-ADJUSTED PVRR (BENEFIT)/COST OF S-02 VS. P-MM ................. 3
TABLE S.4 – RISK-ADJUSTED PVRR (BENEFIT)/COST OF S-03 VS. P-MM ................. 4
TABLE S.5 -- RISK-ADJUSTED PVRR (BENEFIT)/COST OF S-04 VS. P-MM ................ 5
TABLE S.6 -- RISK-ADJUSTED PVRR (BENEFIT)/COST OF S-05 VS. P-MM ................ 5
TABLE S.7 – RISK-ADJUSTED PVRR (BENEFIT)/COST OF S-06 VS. P-MM ................. 7

INDEX OF FIGURES
FIGURE S.1 – INCREASE/(DECREASE) IN NAMEPLATE CAPACITY OF S-01 RELATIVE
TO CASE P-MM .................................................................................................... 2
FIGURE S.2 – INCREASE/(DECREASE) IN NAMEPLATE CAPACITY OF S-02 RELATIVE
TO CASE P-MM .................................................................................................... 3
FIGURE S.3 – INCREASE/(DECREASE) IN NAMEPLATE CAPACITY OF S-03 RELATIVE
TO CASE P-MM .................................................................................................... 4
FIGURE S.4 – INCREASE/(DECREASE) IN NAMEPLATE CAPACITY OF S-04 RELATIVE
TO CASE P-MM .................................................................................................... 6
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FIGURE S.5 – INCREASE/(DECREASE) IN NAMEPLATE CAPACITY OF S-06 RELATIVE
TO CASE P-MM .................................................................................................... 7

PACIFICORP – 2023 IRP SENSITIVITY – MODELING RESULTS
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Additional Sensitivity Analysis
In addition to the studies developed as part of the 2023 Integrated Resource Plan (IRP) portfolio-
development process supporting selection of the preferred portfolio, additional sensitivity cases
were conducted to better understand how certain modeling assumptions influence the resource mix
and timing of future resource additions. These sensitivity cases are useful in understanding how
PacifiCorp’s resource plan would be affected by changes to uncertain planning assumptions and
to address how alternative resources and planning paradigms affect system costs and risk.

To isolate the impact of a given planning assumption, the present value revenue requirement
(PVRR) of the sensitivity cases is compared to the PVRR of the 2023 IRP preferred portfolio,
identified as case P-MM portfolio (medium gas / medium CO2).

P-MM Sensitivity Cases

Table S.1 describes the sensitivity studies conducted under the P-MM case definitions with full
optimization of coal retirement options.

Table S.1 – Summary of P-MM Sensitivity Cases1
Case Description Load Forecast Private
Generation Resources CO2 Policy
S-01 High Load High Low Optimized Medium gas /
Medium CO2
S-02 Low Load Low High Optimized Medium gas /
Medium CO2
S-03 1 in 20 Load
Growth 1 in 20 Base Optimized Medium gas /
Medium CO2
S-04 High Private
Generation Base High Optimized Medium gas /
Medium CO2
S-05 Low Private
Generation Base Low Optimized Medium gas /
Medium CO2
S-06 Business Plan Base Base Align first three
years
Medium gas /
Medium CO2

High Load Growth Sensitivity (S-01)
Table S.2 shows the PVRR impacts of the S-01 sensitivity relative to P-MM. Higher loads result
in increased resource requirements which translate into higher system costs. Figure S.1
summarizes the portfolio impacts. The higher loads resulted in an additional 200 MW of wind and
battery resources on the east side of the system, and an additional 50 MW of solar and battery

1 The numbering sensitivities has been changed from the 2023 IRP filed March 31, 2023. As there will be another
filing on May 31, 2023, inclusive of stakeholder feedback gathered during the 2023 IRP extended comment period,
the 2023 IRP currently filed has not been updated to reflect this. Specifically, the “S-04 20-year Normal” sensitivity
has been removed from Table S.1 this supplement because it was already provided as case “W-11 Climate Change
counterfactual” in the 2023 IRP, Chapter 9 – Modeling and Portfolio Selection Results. Also, Sensitivity “S-08 New
Load” is not included in this supplement as it was also provided in the same chapter.
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resources in the west in 2028. In 2032, an additional 100 MW of wind, solar and battery were
included in the west. In 2034, a Non-Emitting Peaker was added to the east, and in 2037, an
additional 200 MW of solar and battery resources are added to the east. Energy efficiency and
demand response selections increased throughout the study period as well. The higher loads are
also met by increased thermal output and market purchases, and lower sales. CO2 emissions over
the study period increased by 9 million tons.

Table S.2 – Risk-Adjusted PVRR (Benefit)/Cost of S-01 vs. P-MM
(Benefit) / Cost ($ Million)
$1,692

Figure S.1 – Increase/(Decrease) in Nameplate Capacity of S-01 Relative to Case P-MM

Low Load Growth Sensitivity (S-02)
Table S.3 shows the PVRR impacts of the S-02 sensitivity relative to P-MM . The reduced loads
lower system costs over the 20-year study period. Figure S.2 summarizes portfolio impacts. In the
low load sensitivity, 100 MW less of solar and battery were selected in 2028. A further reduction
of 200 MW of battery occurred in 2029 along with 100 MW of wind. Additionally, replacement
resource requirements decreased, reducing the need for 648 MW of non-emitting peaker resources
split between years 2030 and 2036. These changes resulted in lower fuel costs, lower emission
costs, and lower market purchases. CO2 emissions over the study period decreased by 7 million
tons.
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Table S.3 – Risk-Adjusted PVRR (Benefit)/Cost of S-02 vs. P-MM
(Benefit) / Cost ($ Million)
($1,867)

Figure S.2 – Increase/(Decrease) in Nameplate Capacity of S-02 Relative to Case P-MM

1-in-20 Load Growth Sensitivity (S-03)
Table S.4 shows the PVRR impacts of the S-03 sensitivity relative to P-MM. This sensitivity
assumes 1-in-20 extreme weather conditions during the summer (July) for each state. System costs
are approximately $1.3 billion higher due to requirements to meet additional peak load. Figure S.3
summarizes portfolio impacts. In 2028, an additional 550 MW of wind and 500 MW of solar are
selected and matched by an incremental 1,050 MW of battery storage. An additional 342 MW of
demand response and 42 MW of energy efficiency are selected by the end of the study period. 412
MW of non-emitting peaker resources in 2030 replaced the need for 50 MW of wind and 400 MW
of stand-alone battery resources in 2029 and 2030, respectively. A net increase of 1,326 MW of
incremental transmission is selected to support portfolio changes. The high early influx of
renewables and battery storage in 2028 reduces emissions by approximately 13 million tons over
the study period.

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Table S.4 – Risk-Adjusted PVRR (Benefit)/Cost of S-03 vs. P-MM
(Benefit) / Cost ($ Million)
$1,347

Figure S.3 – Increase/(Decrease) in Nameplate Capacity of S-03 Relative to Case P-MM

High Private Generation Sensitivity (S-04)
The High Private Generation sensitivity in the 2023 IRP is substantially similar to the preferred
portfolio. This is driven by the influence of the Inflation Reduction Act, which enacted most of the
drivers previously explaining the circumstances which might lead to higher private generation. In
this sense, the 2023 IRP preferred portfolio already realizes the much of the narrative justifying a
higher private generation future.2 Combined with the high level of overlap between private
generation and solar saturation, no material portfolio changes were indicted in S-04 relative to the
preferred portfolio.

2 See the report accompanying the 2023 IRP, Appendix L – Private Generation, report entitled Private Generation
Forecast, Behind-The-Meter Resource Assessment, page 11,
“The Inflation Reduction Act of 2022 (IRA) extends tax credits for private generation that create very
favorable economics for adoption, and those are embedded in the base case. We therefore limited our upper
bound forecast to lower technology costs and higher retail electricity rates, and these produced only a small
boost to adoption for technologies that were already cost effective under the IRA.”
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Table S.5 shows the PVRR impacts of the High Private S-04 sensitivity relative to P-MM. Higher
private generation assumptions decrease net load, which in turn decreases system costs. The CO2
emissions over the study period decreased by 1 million tons.

Table S.5 -- Risk-Adjusted PVRR (Benefit)/Cost of S-04 vs. P-MM
(Benefit) / Cost ($ Million)
($24)

Low Private Generation Sensitivity (S-05)
Table S.6 shows the PVRR impacts of the S-05 sensitivity relative to P-MM. Lower private
generation creates higher net loads and results in increased system costs, primarily due to increased
proxy resources costs, partially offset by net market transaction benefits. Figure S.4 summarizes
portfolio impacts. From 2028 to 2032, 350 MW of incremental solar and battery storage are added
to the system, followed by an additional 400 MW of solar and 100 MW of battery in 2037. An
additional 352 MW of demand response and 21 MW of energy efficiency are selected by the end
of the study period. A net increase of 706 MW of incremental transmission is selected to support
portfolio changes. CO2 emissions over the study period decreased by 1 million tons.

Table S.6 -- Risk-Adjusted PVRR (Benefit)/Cost of S-05 vs. P-MM
(Benefit) / Cost ($ Million)
$382

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Figure S.4 – Increase/(Decrease) in Nameplate Capacity of S-04 Relative to Case P-MM

Business Plan Sensitivity (S-06)
Table S.7 shows the PVRR impacts of the S-06 sensitivity relative to P-MM. System benefits
increase by $614m. This sensitivity complies with Utah requirements to perform a business plan
sensitivity consistent with the Public Service Commission of Utah’s order in Docket No. 15-035-
04, summarized as follows:

• Over the first three years, resources align with those assumed in PacifiCorp’s December
2022 Business Plan.
• Beyond the first three years of the study period, unit retirement assumptions are aligned
with the preferred portfolio.
• All other resources are optimized.

Figure S.5 reflects the difference between business plan project status as compared to preferred
portfolio proxy resource options in the initial three years of the 20-year study period. This is
observed as reductions or delays in 2020 All-Source Request for Proposals (RFP) wind, solar and
battery storage resources in the business plan relative to the 2023 IRP, primarily in 2025. The
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business plan also reflects increased market reliance and reduced sales. CO2 emissions over the
study period increased by 9 million tons relative to the preferred portfolio.

Table S.7 – Risk-Adjusted PVRR (Benefit)/Cost of S-06 vs. P-MM
(Benefit) / Cost ($ Million)
($614)

Figure S.5 – Increase/(Decrease) in Nameplate Capacity of S-06 Relative to Case P-MM

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