20230809Quarterly Report.pdf

LISA O’HARA
Corporate Counsel
lo’[e-mail]
August 9, 2023
Ms. Jan Noriyuki
Secretary
Idaho Public Utilities Commission
PO Box 83720
Boise, ID 83720-0074
Re: Case No. IPC-E-16-19
Deferral and Recovery of Costs Associated with Participation in Energy Imbalance
Market – California Independent System Operator (“CAISO”) Quarterly Energy
Imbalance Market (“EIM”) Benefits Assessment Report
Dear Ms. Noriyuki:
Pursuant to Order No. 33706 issued in Case No. IPC-E-16-19, Idaho Power Company
(“Idaho Power” or “Company”) hereby submits the quarterly CAISO Western EIM Benefits Report
(“Report”) for the second quarter of 2023. The Report presents CAISO’s quantification of benefits
associated with participation in the Western EIM. For the second quarter of 2023, CAISO
estimated Western EIM gross benefits of $31.52 million for Idaho Power.
The EIM has provided financial benefits to the Company, and ultimately its customers.
However, as discussed in Idaho Power’s prior quarterly compliance filings as well as the
Company’s May 24, 2019, Report of EIM Benefits and Costs of Participation, CAISO’s calculation
of benefits for Idaho Power is overstated due to several of the modeling assumptions used in its
benefit calculation. The Company developed a more precise methodology, that uses inputs
specific to Idaho Power, for determining actual EIM benefits, the details of which are discussed in
the Company’s May 24, 2019, Report of EIM Benefits and Costs of Participation.
If you have any questions regarding this report, please contact Matt Larkin, Revenue
Requirement Senior Manager, at [phone] or [e-mail].
Sincerely,
Lisa J. O’ Hara
Enclosure
RECEIVED
Wednesday, August 9, 2023 4:46:32 PM
IDAHO PUBLIC
UTILITIES COMMISSION

WESTERN ENERGY IMBALANCE MARKET
BENEFITS REPORT
Second Quarter 2023

Prepared by: Market Analysis and Forecasting
July 31, 2023
WEIM BENEFITS REPORT SECOND QUARTER 2023

MPP/MA&F Copyright 2023 California ISO Page 2 of 42

CONTENTS

EXECUTIVE SUMMARY ........................................................................................................ 3
BACKGROUND .................................................................................................................... 4
WEIM ECONOMIC BENEFITS IN Q2 2023 ............................................................................ 5
CUMULATIVE ECONOMIC BENEFITS SINCE INCEPTION ................................................................. 6
INTER-REGIONAL TRANSFERS ........................................................................................................ 6
WHEEL-THROUGH TRANSFERS ....................................................................................................... 9
REDUCED RENEWABLE CURTAILMENT AND GHG REDUCTIONS .................................. 16
FLEXIBLE RAMPING PROCUREMENT DIVERSITY SAVINGS ........................................... 17
CONCLUSION..................................................................................................................... 18
APPENDIX 1: GLOSSARY OF ABBREVIATIONS ............................................................... 19
APPENDIX 2: MAXIMUM TRANSFER CAPACITIES............................................................ 20
APPENDIX 3: MINIMUM & MAXIMUM FLEXIBLE RAMPING REQUIREMENTS .................. 38
WEIM BENEFITS REPORT SECOND QUARTER 2023

MPP/MA&F Copyright 2023 California ISO Page 3 of 42

EXECUTIVE SUMMARY
This report presents the benefits associated with
participation in the Western Energy Imbalance Market
(WEIM).
The measured benefits of participation in the WEIM
include cost savings, increased integration of
renewable energy, and improved operational
efficiencies including the reduction of the need for
real-time flexible reserves.
This analysis demonstrates the benefit of economic
dispatch in the real time market across a larger WEIM
footprint with diverse resources and geography.

Q2 2023 Gross Benefits by Participant
(millions $)
Arizona Public Service $11.95
AVANGRID $8.78
Avista $4.98
BANC $17.72
BPA $7.49
California ISO $70.47
EPE $3.04
Idaho Power $31.52
LADWP $17.09
NV Energy $46.16
NorthWestern Energy $4.44
PacifiCorp $37.49
Portland General Electric $13.84
PNM $7.29
Puget Sound Energy $6.46
Powerex $34.09
Seattle City Light $5.14
Salt River Project $22.83
Tacoma Power $4.86
TEP $5.43
TID $1.72
WALC $17.12
Total $379.91

Gross benefits from WEIM since November 2014
$4.20 billion
ECONOMICAL
$379.91 M
Gross benefits realized due to more
efficient inter-and intra-regional
dispatch in the Fifteen-Minute
Market (FMM) and Real-Time
Dispatch (RTD)*

ENVIRONMENTAL
63,745
Metric tons of CO2** avoided
curtailments

OPERATIONAL
49%
Average reduction in flexibility
reserves across the footprint
2023
Q2 BENEFITS
WEIM BENEFITS REPORT SECOND QUARTER 2023

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*WEIM Quarterly Benefit Report Methodology: https://www.westerneim.com/Documents/EIM-BenefitMethodology.pdf.
**The GHG emission reduction reported is associated with the avoided curtailment only. The current market process and
counterfactual methodology cannot differentiate the GHG emissions resulting from serving ISO load via the WEIM versus dispatch
that would have occurred external to the ISO without the WEIM. For more details, see
http://www.caiso.com/Documents/GreenhouseGasEmissionsTrackingReport-FrequentlyAskedQuestions.pdf
BACKGROUND
The Western EIM began financially binding operation on November 1, 2014, by optimizing
resources across the ISO and PacifiCorp Balancing Authority Areas (BAAs). Since then, the
WEIM has continued to grow and now includes 22 market participants and represents nearly
80% of the demand for electricity in the Western interconnection. Today, the Western EIM
footprint includes portions of Arizona, California, Idaho, Montana, Nevada, New Mexico,
Oregon, Utah, Washington, Wyoming, Texas and extends to the border with Canada.
California ISO 2014
PacifiCorp 2014
NV Energy 2015
Arizona Public Service 2016
Puget Sound Energy 2016
Portland General Electric 2017
Powerex 2018
Idaho Power 2018
BANC 2019
Seattle City Light 2020
Salt River Project 2020
TID 2021
PNM 2021
LADWP 2021
NorthWestern Energy 2021
Tacoma Power 2022
Avista 2022
TEP 2022
BPA 2022
AVANGRID 2023
EPE 2023
WALC 2023
TABLE 1: WEIM participants

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WEIM ECONOMIC BENEFITS IN Q2 2023
Table 2 shows the estimated WEIM gross benefits by each region per month1. The monthly
savings presented show $150.21 million for April, $105.89 million for May, and $123.81 million
for June with a total estimated benefit of $379.91 million for this quarter2. This level of WEIM
benefits accrued from having additional WEIM areas participating in the market and economical
transfers displacing more expensive generation.
Region April May June Total
APS $6.78 $2.48 $2.69 $11.95
AVRN $4.48 $2.46 $1.84 $8.78
AVA $2.44 $1.50 $1.04 $4.98
BANC $9.74 $4.79 $3.19 $17.72
BPA $3.60 $2.29 $1.60 $7.49
CISO $25.29 $19.98 $25.20 $70.47
EPE $1.41 $0.79 $0.84 $3.04
IPCO $8.43 $17.86 $5.23 $31.52
LADWP $6.59 $6.28 $4.22 $17.09
NVE $20.32 $8.89 $16.95 $46.16
NWMT $2.75 $0.99 $0.70 $4.44
PAC $10.78 $11.87 $14.84 $37.49
PGE $5.87 $3.82 $4.15 $13.84
PNM $3.93 $1.75 $1.61 $7.29
PSE $3.44 $1.06 $1.96 $6.46
PWRX $12.25 $3.15 $18.69 $34.09
SCL $2.33 $1.21 $1.60 $5.14
SRP $11.05 $5.34 $6.44 $22.83
TPWR $3.00 $0.59 $1.27 $4.86
TEP $3.09 $1.30 $1.04 $5.43
TID $0.90 $0.53 $0.29 $1.72
WALC $1.74 $6.96 $8.42 $17.12
Total $150.21 $105.89 $123.81 $379.91
TABLE 2: Q2 2023 benefits in millions USD

1 The WEIM benefits reported here are calculated based on available data. Intervals without complete data are
excluded in the calculation. The intervals excluded due to unavailable data are normally within a few percent
points of the total intervals.
2 For several quarterly estimates, CAISO benefits were calculated on a variation of the counterfactual
methodology. For CAISO only the logic had considered offline resources as part of the bid stack in the
counterfactual. In Q4 2021, CAISO identified some questionable results that drove persistent negative benefits
for CAISO when considering offline resources. Since Q4 2021, the benefit calculation for CAISO area follows
the same methodology applicable to all WEIM entities in which only online resources are used.
WEIM BENEFITS REPORT SECOND QUARTER 2023

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CUMULATIVE ECONOMIC BENEFITS SINCE INCEPTION
Since the start of the WEIM in November 2014, the cumulative economic benefits of the market
have totaled $4.20 billion. The quarterly benefits have grown over time as a result of the
participation of new BAAs, which results in benefits for both the individual BAA but also
compounds the benefits to adjacent BAAs through additional transfers. The ISO began
publishing quarterly WEIM benefit reports in April 2015.3
Graph 1 illustrates the gross economic benefits of the WEIM by quarter for each participating
BAA.

GRAPH 1: Cumulative economic benefits for each quarter by BAA
INTER-REGIONAL TRANSFERS
A significant contributor to WEIM benefits is transfers across balancing areas, providing access
to lower cost supply, while factoring in the cost of compliance with greenhouse gas (GHG)
emissions regulations when energy is transferred into the ISO. As such, the transfer volumes
are a good indicator of a portion of the benefits attributed to the WEIM. Transfers can take place
in both the 15-Minute Market and Real-Time Dispatch (RTD).
Generally, transfer limits are based on transmission and interchange rights that participating
balancing authority areas make available to the WEIM, with the exception of the PacifiCorp
West (PACW) -ISO transfer limit and the Portland General Electric (PGE) -ISO transfer limit in
RTD. These RTD transfer capacities between PACW/PGE and the ISO are determined based
on the allocated dynamic transfer capability driven by system operating conditions. This report

3 Prior reports are available at https://www.westerneim.com/Pages/About/QuarterlyBenefits.aspx
WEIM BENEFITS REPORT SECOND QUARTER 2023

MPP/MA&F Copyright 2023 California ISO Page 7 of 42
does not quantify a BAA’s opportunity cost that the utility considered when using its transfer
rights for the WEIM.
Appendix 2 provides the 15-minute and 5-minute WEIM transfer volumes with base schedule
transfers excluded. The WEIM entities submit inter-BAA transfers in their base schedules. The
benefits quantified in this report are only attributable to the transfers that occurred through the
WEIM. The benefits do not include any transfers attributed to transfers submitted in the base
schedules that are scheduled prior to the start of the WEIM.
The transfer from BAA_x to BAA_y and the transfer from BAA_y to BAA_x are separately
reported. For example, if there is a 100 Megawatt-Hour (MWh) transfer during a 5-minute
interval, in addition to a base transfer from ISO to NVE, it will be reported as 100 MWh
from_BAA ISO to_BAA NEVP, and 0 MWh from_BAA NEVP to_BAA ISO in the opposite
direction. The 15-minute transfer volume is the result of optimization in the 15-minute market
using all bids and base schedules submitted into the WEIM. The 5-minute transfer volume is the
result of optimization using all bids and base schedules submitted into WEIM, based on unit
commitments determined in the 15-minute market optimization. The maximum transfer
capacities between WEIM entities are shown in Appendix 2: Maximum Transfer Capacities.

WEIM BENEFITS REPORT SECOND QUARTER 2023

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GRAPH 2: WEIM transfer
WEIM BENEFITS REPORT SECOND QUARTER 2023

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WHEEL-THROUGH TRANSFERS
As the footprint of the WEIM grows, wheel-through transfers may become more common. In
order to derive the wheel-through transfers for each WEIM BAA, the ISO uses the following
calculation for every real-time interval dispatch:

 Total import: summation of transfers above base transfers coming into the WEIM
BAA under analysis
 Total export: summation of all transfers above base transfers going out of the WEIM
BAA under analysis
 Net import: the maximum of zero or the difference between total imports and total
exports
 Net export: the maximum of zero or the difference between total exports and total
imports
 Wheel-through: the minimum of the WEIM transfers into (total import) or WEIM
transfer out (total export) of a BAA for a given interval

All wheel-through transfers are summed over both the month and the quarter.

Currently, a WEIM entity facilitating a wheel through receives no direct financial benefit for
facilitating the wheel; only the sink and source directly benefit. As part of the WEIM
Consolidated Initiatives stakeholder process, the ISO committed to monitoring the wheel
through volumes to assess whether, after the addition of new WEIM entities, there is a potential
future need to pursue a market solution to address the equitable sharing of wheeling benefits.

The ISO will continue to track the volume of wheel-through transfers in the WEIM market in the
quarterly reports.

This volume reflects the total wheel-through transfers for each WEIM BAA, regardless of the
potential paths used to wheel through. The net imports and exports estimated in this section
reflect the overall volume of net imports and exports; in contrast, the imports and exports
provided in Table 2 reflect the gross transfers between two WEIM BAAs.

The metric is measured as energy in MWh for each month and the corresponding calendar
quarter, as shown in Tables 3 through 6 and Graphs 3 through 6.

BAA Net Export Net Import Wheel Through
AVA

83,708

170,476

65,387
AVRN

215,524

42,904

42,335
AZPS

268,828

262,500

594,887
BANC

82,686

242,637

-
BPAT

206,468

177,798

141,432
WEIM BENEFITS REPORT SECOND QUARTER 2023

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TABLE 3: Estimated wheel-through transfers in Q2 2023

CISO

2,758,377

552,611

588,055
EPE

135,298

70,983

72
IPCO

66,404

314,349

296,746
LADWP

146,132

233,543

121,801
NEVP

531,979

122,291

423,789
NWMT

65,081

48,051

57,983
PACE

145,515

1,057,669

191,496
PACW

222,215

76,703

455,045
PGE

81,416

310,021

100,230
PNM

148,523

97,109

106,910
PSEI

114,170

203,698

147,262
PWRX

4,583

1,005,970

13,819
SCL

16,380

116,835

21,663
SRP

564,023

461,313

150,218
TEPC

178,019

337,524

78,230
TIDC

26,769

40,453

-
TPWR

10,154

64,412

18,361
WALC

15,285

77,686

206,647
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GRAPH 3: Estimated wheel-through transfers in Q2 2023

BAA
Net Export Net Import Wheel Through
AVA

13,905

64,563

15,506
AVRN

61,861

14,989

13,969
AZPS

121,457

53,838

161,576
BANC

26,610

80,005

-
BPAT

51,839

78,988

73,511
CISO

714,265

192,065

267,543
EPE

38,198

9,655

-
IPCO

36,160

66,661

120,424
LADWP

66,911

60,296

23,187
NEVP

165,012

35,659

124,786
NWMT

40,411

6,877

12,557
PACE

58,542

303,973

77,749
PACW

71,031

15,652

158,406
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PGE

18,789

110,173

41,402
PNM

63,906

11,852

31,180
PSEI

53,791

75,682

46,512
PWRX

907

399,482

5,695
SCL

3,866

52,064

5,777
SRP

193,201

152,145

35,154
TEPC

63,820

63,807

23,184
TIDC

14,504

12,730

-
TPWR

3,646

17,733

5,147
WALC

6,072

9,818

33,303

TABLE 4: Estimated wheel-through transfers in April 2023

GRAPH 4: Estimated wheel-through transfers in April 2023

WEIM BENEFITS REPORT SECOND QUARTER 2023
MPP/MA&F Copyright 2023 California ISO Page 13 of 42
BAA Net Export Net Import Wheel Through
AVA 50,639 27,639 33,824
AVRN 82,119 12,298 16,028
AZPS 51,454 110,503 206,315
BANC 35,715 97,092 -
BPAT 97,642 33,326 27,192
CISO 972,500 158,792 123,775
EPE 37,229 34,252 34
IPCO 12,228 112,093 73,833
LADWP 39,248 97,536 53,494
NEVP 153,920 58,504 155,017
NWMT 11,336 23,734 20,108
PACE 34,958 416,454 19,433
PACW 88,983 22,901 137,422
PGE 33,934 77,365 30,163
PNM 45,526 33,534 32,972
PSEI 33,478 55,684 45,514
PWRX 2,521 191,180 2,801
SCL 7,839 13,176 11,153
SRP 142,958 169,501 69,867
TEPC 33,498 153,387 22,389
TIDC 2,242 17,621 -
TPWR 4,852 17,611 8,247
WALC 6,693 47,329 74,400
TABLE 5: Estimated wheel-through transfers in May 2023
WEIM BENEFITS REPORT SECOND QUARTER 2023

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GRAPH 5: Estimated wheel-through transfers in May 2023

BAA Net Export Net Import Wheel Through
AVA

19,164

78,274

16,057
AVRN

71,544

15,617

12,339
AZPS

95,917

98,159

226,996
BANC

20,361

65,540

-
BPAT

56,987

65,484

40,729
CISO

1,071,612

201,754

196,737
EPE

59,871

27,076

38
IPCO

18,015

135,595

102,490
LADWP

39,973

75,712

45,120
NEVP

213,046

28,128

143,986
NWMT

13,334

17,440

25,318
PACE

52,016

337,242

94,314
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PACW

62,201

38,150

159,217
PGE

28,693

122,483

28,666
PNM

39,092

51,723

42,758
PSEI

26,901

72,332

55,236
PWRX

1,154

415,308

5,323
SCL

4,674

51,595

4,734
SRP

227,863

139,667

45,197
TEPC

80,701

120,330

32,657
TIDC

10,023

10,103

-
TPWR

1,656

29,068

4,967
WALC

2,520

20,538

98,944

TABLE 6: Estimated wheel-through transfers in June 2023

GRAPH 6: Estimated wheel-through transfers in June 2023
WEIM BENEFITS REPORT SECOND QUARTER 2023

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REDUCED RENEWABLE CURTAILMENT AND GHG REDUCTIONS
The WEIM benefit calculation includes the economic benefits that can be attributed to avoided
renewable curtailment within the ISO footprint. If not for energy transfers facilitated by the
WEIM, some renewable generation located within the ISO would have been curtailed via either
economic or exceptional dispatch. The total avoided renewable curtailment volume in MWh for
Q2 2023 was calculated to be 38,770 MWh (April) + 57,896 MWh (May) + 52,272 MWh (June) =
148,938 MWh total.
There are environmental benefits of avoided renewable curtailment as well. Under the
assumption that avoided renewable curtailments displace production from other resources at a
default emission rate of 0.428 metric tons CO2/MWh, avoided curtailments displaced an
estimated 63,745 metric tons of CO2 for Q2 2023. Avoided renewable curtailments also may
have contributed to an increased volume of renewable credits that would otherwise have been
unavailable. This report does not quantify the additional value in dollars associated with this
benefit. Total estimated reductions in the curtailment of renewable energy in the ISO footprint,
along with the associated reductions in CO2, are shown in Table 7.
Year Quarter MWh Eq. Tons CO2
1 8,860 3,792
2015 2 3,629 1,553
3 828 354
4 17,765 7,521
1 112,948 48,342
2016 2 158,806 67,969
3 33,094 14,164
4 23,390 10,011
1 52,651 22,535
2017 2 67,055 28,700
3 23,331 9,986
4 18,060 7,730
1 65,860 28,188
2018 2 129,128 55,267
3 19,032 8,146
4 23,425 10,026
1 52,254 22,365
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2019 2 132,937 56,897
3 33,843 14,485
4 35,254 15,089
1 86,740 37,125
2020 2 147,514 63,136
3 37,548 16,071
4 39,956 17,101
2021 1 76,147 32,591
2 109,059 46,677
3 23,042 9,862
4 38,044 16,283
2022 1 94,168 40,304
2 118,352 50,655
3 42,468 18,176
4 25,609 10,960
2023 1 53,002 22,685
2 148,938 63,745
Total 2,052,737 878,491

TABLE 7: Total reduction in curtailment of renewable energy and associated reductions in CO2
FLEXIBLE RAMPING PROCUREMENT DIVERSITY SAVINGS
The WEIM facilitates procurement of flexible ramping capacity in the FMM to address variability
that may occur in the RTD. Because variability across different BAAs may happen in opposite
directions, the flexible ramping requirement for the entire WEIM footprint can be less than the
sum of individual BAA’s requirements. This difference is known as flexible ramping procurement
diversity savings.
Starting in 2016, the ISO replaced the flexible ramping constraint with flexible ramping products
that provide both upward and downward ramping. The minimum and maximum flexible ramping
requirements for each BAA and for each direction are listed in Appendix 3: Minimum &
Maximum Ramping Requirements.

The flexible ramping procurement diversity savings for all the intervals averaged over the month
are shown in Table 7. The percentage savings is the average MW savings divided by the sum of
the individual BAA requirements.
WEIM BENEFITS REPORT SECOND QUARTER 2023

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April May June
Direction Up Down Up Down Up Down
Average MW saving 1,747

1,006 1,745 1,668 1,744 1,227
Sum of BAA requirements 3,057 2,900 3,127 3,078 3,258 3,265
Percentage savings 57% 35% 56% 54% 54% 38%
Table 8: Flexible ramping procurement diversity savings in Q2 2023
Flexible ramping capacity may be used in RTD to handle uncertainties in the future interval. The
RTD flexible ramping capacity is prorated to each BAA. Flexible ramping surplus MW is defined
as the awarded flexible ramping capacity in RTD minus its share, and the flexible ramping
surplus cost is defined as the flexible ramping surplus MW multiplied by the flexible ramping
WEIM-wide marginal price. A positive flexible ramping surplus MW is the capacity that a BAA
provided to help other BAAs, and a negative flexible ramping surplus MW is the capacity that a
BAA received from other BAAs.
The WEIM dispatch cost for a BAA with positive flexible ramping surplus MW is increased
because some capacities are used to help other BAAs. The flexible ramping surplus cost is
subtracted from the BAA’s WEIM dispatch cost to reflect the true dispatch cost of a BAA. Please
see the Benefit Report Methodology for more details.
CONCLUSION
Using state-of-the-art technology to find and deliver low-cost energy to meet real-time demand,
the WEIM demonstrates that utilities can realize financial and operational benefits through
increased coordination and optimization. In addition to these benefits, the WEIM provides
significant environmental benefits through the reduction of renewable curtailments during
periods of oversupply.
Sharing resources across a larger geographic area reduces greenhouse gas emissions by using
renewable generation that otherwise would have been turned off. The quantified environmental
benefits from avoided curtailments of renewable generation from 2015 to-date reached 878,491
metric tons of CO2, roughly the equivalent of avoiding the emissions from 184,699 passenger
cars driven for one year.

WEIM BENEFITS REPORT SECOND QUARTER 2023

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APPENDIX 1: GLOSSARY OF ABBREVIATIONS

Abbreviation Description
APS Arizona Public Service
AVA Avista Utilities
AVRN Avangrid
BAA Balancing Authority Area
BANC Balancing Authority of Northern California
BPA Bonneville Power Administration
CISO, ISO California ISO
EIM Energy Imbalance Market
EPE El Paso Electric
FMM Fifteen Minute Market
GHG Greenhouse Gas
IPCO Idaho Power
LADWP Los Angeles Department of Water and Power
MW Megawatt
MWh Megawatt-Hour
NVE NV Energy
PAC PacifiCorp
PACE PacifiCorp East
PACW PacifiCorp West
PGE Portland General Electric
PSE Puget Sound Energy
PWRX Powerex
RTD Real Time Dispatch
SCL Seattle City Light
SRP Salt River Project
TEP Tucson Electric Power
TID Turlock Irrigation District
TPWR Tacoma Power
WALC
Western Area Power Administration Desert
Southwest
WEIM Western Energy Imbalance Market

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APPENDIX 2: Maximum Transfer Capacities

Month

From BAA

To BAA
15min WEIM transfer
(15m – base)
5min WEIM transfer
(5m – base)
AVA AVRN 8 0
April AVA BPAT 13,044 13,809
AVA CISO 0 0
AVA IPCO 10,714 7,409
AVA NWMT 9,124 6,251
AVA PACW 1,262 1,941
AVA PGE 0 0
AVA PSEI 0 0
AVA SCL 4 0
AVA TPWR 0 0
AVRN AVA 0 0
AVRN BPAT 33,026 32,478
AVRN PACW 17,869 24,875
AVRN PGE 18,395 16,586
AVRN SCL 1,862 1,890
AZPS CISO 84,067 68,551
AZPS EPE 2,289 0
AZPS LADWP 21,672 24,834
AZPS NEVP 5,481 6,376
AZPS PACE 152,693 153,445
AZPS PNM 13,235 13,894
AZPS SRP 7,404 8,791
AZPS TEPC 4,790 6,674
April AZPS WALC 1,344 468
BANC BPAT 0 0
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BANC CISO 27,573 23,849
BANC TIDC 3,101 2,761
BPAT AVA 10,083 6,765
BPAT AVRN 4,770 5,601
BPAT BANC 0 0
BPAT CISO 14,597 21,086
BPAT IPCO 9,354 3,702
BPAT LADWP 0 0
BPAT NEVP 0 0
BPAT NWMT 10,368 4,644
BPAT PACW 4,335 1,393
BPAT PGE 23,818 21,309
BPAT PSEI 30,438 37,541
BPAT PWRX 7,414 0
BPAT SCL 9,095 8,420
BPAT TPWR 12,087 14,888
CISO AVA 0 0
CISO AZPS 101,243 82,079
CISO BANC 59,773 71,661
CISO BPAT 23,030 30,020
CISO LADWP 40,607 38,677
CISO NEVP 78,374 81,354
CISO PACW 16,540 48,624
CISO PGE 30,429 56,245
CISO PWRX 359,142 379,151
April CISO SRP 165,944 169,621
CISO TEPC 1,073 1,589
CISO TIDC 8,787 9,969
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CISO WALC 11,867 12,819
EPE AZPS 1,273 0
EPE PNM 16,971 16,594
EPE TEPC 23,328 21,604
IPCO AVA 39,888 44,792
IPCO BPAT 21,816 24,317
IPCO NEVP 24,852 15,033
IPCO NWMT 241 523
IPCO PACE 31,419 20,816
IPCO PACW 39,170 37,424
IPCO PSEI 1,943 1,864
IPCO SCL 11,383 11,815
LADWP AZPS 6,195 8,551
LADWP BPAT 0 0
LADWP CISO 32,904 23,616
LADWP NEVP 35,387 36,659
LADWP PACE 22,448 20,960
LADWP TEPC 0 0
LADWP WALC 1,273 312
NEVP AZPS 535 977
NEVP BPAT 0 0
NEVP CISO 48,753 31,656
NEVP IPCO 83,761 76,691
NEVP LADWP 17,106 14,723
NEVP PACE 175,549 161,882
April NEVP WALC 6,298 3,870
NWMT AVA 13,690 15,554
NWMT BPAT 2,988 2,774
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NWMT IPCO 11,557 11,329
NWMT PACE 28,867 23,312
NWMT PACW 19 0
NWMT PGE 47 0
NWMT PSEI 163 0
NWMT TPWR 0 0
PACE AZPS 33,678 25,536
PACE IPCO 56,365 56,020
PACE LADWP 4,469 2,457
PACE NEVP 7,673 7,494
PACE NWMT 8,048 8,016
PACE PACW 41,911 36,768
PACE SRP 0 0
PACE TEPC 13 0
PACW AVA 12,170 12,958
PACW AVRN 12,309 20,889
PACW BPAT 8,817 8,763
PACW CISO 22,237 41,312
PACW IPCO 24,451 24,641
PACW NWMT 7 0
PACW PGE 54,950 54,762
PACW PSEI 57,681 64,230
PACW SCL 1,855 1,883
PGE AVA 0 0
PGE AVRN 708 1,184
April PGE BPAT 18,280 21,335
PGE CISO 26,381 23,320
PGE NWMT 47 0
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MPP/MA&F Copyright 2023 California ISO Page 24 of 42
PGE PACW 7,365 8,525
PGE PSEI 3,309 4,422
PGE SCL 1,412 1,405
PGE TPWR 0 0
PNM AZPS 92,070 72,206
PNM EPE 4,505 5,932
PNM SRP 1,762 1,544
PNM TEPC 16,319 15,404
PSEI AVA 0 0
PSEI BPAT 13,123 14,337
PSEI IPCO 4,389 3,321
PSEI NWMT 76 0
PSEI PACW 12,851 14,179
PSEI PGE 1,759 2,021
PSEI PWRX 26,166 26,026
PSEI SCL 35,070 32,428
PSEI TPWR 7,732 7,992
PWRX BPAT 9,317 0
PWRX CISO 0 0
PWRX PSEI 6,228 6,603
SCL AVA 9 0
SCL AVRN 818 1,284
SCL BPAT 604 538
SCL IPCO 4,462 3,973
SCL PACW 249 329
April SCL PGE 558 652
SCL PSEI 1,475 2,868
SRP AZPS 25,472 25,068
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SRP CISO 173,447 169,708
SRP PACE 0 0
SRP PNM 107 104
SRP TEPC 28,530 31,886
SRP WALC 2,369 1,590
TEPC AZPS 633 18
TEPC CISO 44,257 38,474
TEPC EPE 3,187 3,723
TEPC LADWP 0 0
TEPC PACE 1,724 1,307
TEPC PNM 12,055 12,439
TEPC SRP 11,966 6,979
TEPC WALC 25,210 24,064
TIDC BANC 8,866 8,344
TIDC CISO 7,866 6,160
TPWR AVA 0 0
TPWR BPAT 4,293 4,127
TPWR NWMT 0 0
TPWR PGE 0 0
TPWR PSEI 3,767 4,666
WALC AZPS 2,948 979
WALC CISO 15,034 11,877
WALC LADWP 3,624 2,792
WALC NEVP 16,692 13,528
WALC SRP 1,017 364
WALC TEPC 9,752 9,835
May AVA AVRN 0 0
AVA BPAT 2,132 1,656
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AVA CISO 0 0
AVA IPCO 60,157 54,960
AVA NWMT 29,351 24,539
AVA PACW 1,600 3,307
AVA PGE 25 0
AVA PSEI 2 0
AVA SCL 4 0
AVA TPWR 0 0
AVRN AVA 0 0
AVRN BPAT 24,758 19,509
AVRN PACW 57,227 61,645
AVRN PGE 16,588 12,735
AVRN SCL 5,799 4,258
AZPS CISO 34,589 20,557
AZPS EPE 2,020 0
AZPS LADWP 15,897 19,460
AZPS PACE 180,841 160,032
AZPS PNM 46,416 51,501
AZPS SRP 3,012 2,727
AZPS TEPC 896 2,917
AZPS WALC 719 575
BANC BPAT 0 0
BANC CISO 37,078 34,579
BANC TIDC 1,329 1,136
BPAT AVA 22,203 20,161
May BPAT AVRN 10,902 13,333
BPAT BANC 0 0
BPAT CISO 4,856 9,479
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BPAT IPCO 3,714 3,127
BPAT LADWP 0 0
BPAT NEVP 0 0
BPAT NWMT 6,142 3,400
BPAT PACW 1,527 2,047
BPAT PGE 20,563 23,364
BPAT PSEI 27,271 30,466
BPAT PWRX 7,184 0
BPAT SCL 2,094 1,821
BPAT TPWR 15,171 17,635
CISO AVA 0 0
CISO AZPS 216,535 196,667
CISO BANC 83,645 97,000
CISO BPAT 1,550 2,232
CISO LADWP 87,510 87,553
CISO NEVP 168,668 151,426
CISO PACW 9,939 35,070
CISO PGE 30,197 46,690
CISO PWRX 151,219 168,662
CISO SRP 235,483 232,733
CISO TEPC 977 882
CISO TIDC 16,158 16,485
CISO WALC 64,657 60,874
EPE AZPS 1,511 0
EPE PNM 10,794 10,747
May EPE TEPC 30,524 26,516
IPCO AVA 16,909 13,892
IPCO BPAT 2,251 1,057
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IPCO NEVP 20,519 17,085
IPCO NWMT 2,720 3,384
IPCO PACE 39,701 34,663
IPCO PACW 5,280 3,300
IPCO PSEI 9,089 8,712
IPCO SCL 3,712 3,967
LADWP AZPS 5,405 9,514
LADWP BPAT 0 0
LADWP CISO 15,210 9,967
LADWP NEVP 36,602 30,878
LADWP PACE 36,458 40,358
LADWP TEPC 0 0
LADWP WALC 1,796 2,025
NEVP AZPS 0 0
NEVP BPAT 0 0
NEVP CISO 29,448 17,082
NEVP IPCO 80,596 74,156
NEVP LADWP 24,596 23,719
NEVP PACE 196,834 180,685
NEVP WALC 7,065 13,297
NWMT AVA 6,773 7,584
NWMT BPAT 3,612 157
NWMT IPCO 3,353 3,627
NWMT PACE 23,747 20,075
NWMT PACW 169 0
NWMT PGE 164 0
May NWMT PSEI 167 0
NWMT TPWR 0 0
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MPP/MA&F Copyright 2023 California ISO Page 29 of 42

PACE AZPS 10,978 15,931
PACE IPCO 11,582 8,716
PACE LADWP 11,140 9,840
PACE NEVP 2,660 2,283
PACE NWMT 12,361 12,519
PACE PACW 9,118 5,101
PACE SRP 0 0
PACE TEPC 0 0
PACW AVA 21,880 19,825
PACW AVRN 3,021 11,256
PACW BPAT 4,796 861
PACW CISO 35,550 98,588
PACW IPCO 32,905 29,667
PACW NWMT 30 0
PACW PGE 31,047 23,827
PACW PSEI 42,672 41,260
PACW SCL 1,276 1,120
PGE AVA 0 0
PGE AVRN 1,155 2,539
PGE BPAT 22,280 20,838
PGE CISO 12,786 11,820
PGE NWMT 112 0
PGE PACW 22,875 27,652
PGE PSEI 0 0
PGE SCL 1,450 1,247
PGE TPWR 0 0
May PNM AZPS 52,734 38,942
PNM EPE 22,758 26,509
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PNM SRP 1,488 1,197
PNM TEPC 14,412 11,850
PSEI AVA 0 0
PSEI BPAT 14,194 11,665
PSEI IPCO 0 0
PSEI NWMT 49 0
PSEI PACW 12,951 21,675
PSEI PGE 126 195
PSEI PWRX 26,368 25,319
PSEI SCL 12,966 11,915
PSEI TPWR 7,145 8,224
PWRX BPAT 4,242 0
PWRX CISO 0 0
PWRX PSEI 4,408 5,322
SCL AVA 6 0
SCL AVRN 441 1,197
SCL BPAT 254 372
SCL IPCO 13,038 11,671
SCL PACW 245 526
SCL PGE 514 716
SCL PSEI 3,058 4,510
SRP AZPS 40,578 54,084
SRP CISO 82,843 64,900
SRP PACE 0 0
SRP PNM 186 219
SRP TEPC 78,547 85,430
May SRP WALC 8,175 8,192
TEPC AZPS 1,144 422
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TEPC CISO 8,588 4,277
TEPC EPE 7,530 7,777
TEPC LADWP 0 0
TEPC PACE 133 75
TEPC PNM 6,028 4,039
TEPC SRP 3,797 2,531
TEPC WALC 46,872 36,766
TIDC BANC 102 93
TIDC CISO 2,628 2,149
TPWR AVA 0 0
TPWR BPAT 1,983 2,171
TPWR NWMT 0 0
TPWR PGE 0 0
TPWR PSEI 8,913 10,928
WALC AZPS 2,169 1,257
WALC CISO 18,414 9,168
WALC LADWP 12,849 10,458
WALC NEVP 13,976 11,849
WALC SRP 709 180
WALC TEPC 48,612 48,180
June AVA AVRN 66 192
AVA BPAT 14,440 11,504
AVA CISO 0 0
AVA IPCO 13,168 13,227
AVA NWMT 7,240 8,847
AVA PACW 1,620 1,451
June AVA PGE 0 0
AVA PSEI 5 0
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MPP/MA&F Copyright 2023 California ISO Page 32 of 42
AVA SCL 18 0
AVA TPWR 0 0
AVRN AVA 232 111
AVRN BPAT 30,742 24,649
AVRN PACW 45,377 43,293
AVRN PGE 11,143 8,869
AVRN SCL 7,872 6,960
AZPS CISO 51,913 45,605
AZPS EPE 2,432 0
AZPS LADWP 21,865 22,227
AZPS PACE 233,964 190,540
AZPS PNM 47,971 57,499
AZPS SRP 4,336 3,356
AZPS TEPC 2,669 3,328
AZPS WALC 1,597 357
BANC BPAT 0 0
BANC CISO 18,337 20,361
BANC TIDC 29 0
BPAT AVA 8,615 9,128
BPAT AVRN 2,678 4,496
BPAT BANC 0 0
BPAT CISO 1,770 5,711
BPAT IPCO 3,279 2,916
BPAT LADWP 0 0
BPAT NEVP 0 0
BPAT NWMT 6,779 3,520
June BPAT PACW 1,910 972
BPAT PGE 9,307 9,560
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MPP/MA&F Copyright 2023 California ISO Page 33 of 42
BPAT PSEI 28,238 31,588
BPAT PWRX 7,247 0
BPAT SCL 5,014 4,908
BPAT TPWR 24,624 24,918
CISO AVA 0 0
CISO AZPS 204,909 212,561
CISO BANC 63,913 65,540
CISO BPAT 6,201 13,822
CISO LADWP 70,197 61,917
CISO NEVP 150,132 127,174
CISO PACW 14,998 60,569
CISO PGE 68,472 94,909
CISO PWRX 371,977 396,272
CISO SRP 175,740 178,273
CISO TEPC 2,728 3,050
CISO TIDC 10,378 10,103
CISO WALC 43,523 43,878
EPE AZPS 806 0
EPE PNM 20,102 22,661
EPE TEPC 43,588 37,248
IPCO AVA 56,664 56,242
IPCO BPAT 13,342 10,263
IPCO NEVP 3,929 4,563
IPCO NWMT 2,628 3,410
IPCO PACE 15,560 15,007
IPCO PACW 35,097 20,233
June IPCO PSEI 0 0
IPCO SCL 12,294 10,788
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MPP/MA&F Copyright 2023 California ISO Page 34 of 42

LADWP AZPS 3,373 5,972
LADWP BPAT 0 0
LADWP CISO 23,324 16,377
LADWP NEVP 18,926 18,488
LADWP PACE 46,345 42,882
LADWP TEPC 0 0
LADWP WALC 1,961 1,374
NEVP AZPS 0 0
NEVP BPAT 0 0
NEVP CISO 35,458 29,212
NEVP IPCO 152,301 129,532
NEVP LADWP 17,733 17,850
NEVP PACE 192,023 171,510
NEVP WALC 7,325 8,930
NWMT AVA 25,159 22,839
NWMT BPAT 4,075 1,666
NWMT IPCO 2,471 2,796
NWMT PACE 10,859 11,350
NWMT PACW 51 0
NWMT PGE 181 0
NWMT PSEI 197 0
NWMT TPWR 0 0
PACE AZPS 9,082 11,983
PACE IPCO 65,870 53,651
PACE LADWP 9,080 7,559
PACE NEVP 1,199 1,381
PACE NWMT 27,193 26,982
June PACE PACW 66,664 44,774
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PACE SRP 0 0
PACE TEPC 0 0
PACW AVA 4,842 6,011
PACW AVRN 8,379 20,194
PACW BPAT 4,230 3,230
PACW CISO 18,356 40,432
PACW IPCO 32,686 32,624
PACW NWMT 3 0
PACW PGE 49,457 37,457
PACW PSEI 83,598 79,470
PACW SCL 2,140 2,000
PGE AVA 0 0
PGE AVRN 1,143 2,363
PGE BPAT 28,959 26,687
PGE CISO 6,088 6,057
PGE NWMT 163 0
PGE PACW 17,425 20,372
PGE PSEI 2 0
PGE SCL 1,962 1,881
PGE TPWR 0 0
PNM AZPS 65,637 54,775
PNM EPE 16,894 18,559
PNM SRP 732 566
PNM TEPC 9,838 7,949
PSEI AVA 1 0
PSEI BPAT 13,887 12,682
PSEI IPCO 0 0
June PSEI NWMT 89 0
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MPP/MA&F Copyright 2023 California ISO Page 36 of 42
PSEI PACW 2,982 5,538
PSEI PGE 0 0
PSEI PWRX 26,709 24,359
PSEI SCL 32,854 29,791
PSEI TPWR 8,701 9,118
PWRX BPAT 3,439 0
PWRX CISO 0 0
PWRX PSEI 5,201 6,477
SCL AVA 57 0
SCL AVRN 405 711
SCL BPAT 382 434
SCL IPCO 2,697 3,339
SCL PACW 60 165
SCL PGE 315 354
SCL PSEI 3,863 4,405
SRP AZPS 30,465 39,142
SRP CISO 185,801 173,627
SRP PACE 0 0
SRP PNM 736 980
SRP TEPC 49,690 56,201
SRP WALC 3,838 3,109
TEPC AZPS 1,016 0
TEPC CISO 35,169 26,948
TEPC EPE 6,699 8,555
TEPC LADWP 0 0
TEPC PACE 252 267
TEPC PNM 12,188 13,341
June TEPC SRP 3,844 2,412
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MPP/MA&F Copyright 2023 California ISO Page 37 of 42

TEPC WALC 65,876 61,834
TIDC BANC 33 0
TIDC CISO 9,836 10,023
TPWR AVA 0 0
TPWR BPAT 1,132 1,277
TPWR NWMT 0 0
TPWR PGE 0 0
TPWR PSEI 5,206 5,347
WALC AZPS 2,590 722
WALC CISO 30,840 23,488
WALC LADWP 10,081 11,279
WALC NEVP 26,096 20,508
WALC SRP 869 256
WALC TEPC 46,586 45,211
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MPP/MA&F Copyright 2023 California ISO Page 38 of 42
APPENDIX 3: Minimum & Maximum Flexible Ramping Requirements

Month BAA Direction Minimum
requirement
Maximum
requirement
AVA up 5 99
April AVRN up 0 165
AZPS up 0 298
BANC up 0 103
BPAT up 9 426
CISO up 0 2,404
EPE up 0 53
IPCO up 11 155
LADWP up 0 415
NEVP up 0 478
NWMT up 0 138
PACE up 0 479
PACW up 0 185
PGE up 0 192
PNM up 0 165
PSEI up 0 230
PWRX up 0 325
SCL up 0 51
SRP up 0 280
TEPC up 0 195
TIDC up 0 20
TPWR up 0 22
WALC up 0 27
ALL EIM up 315 2,771
AVA down 0 97
AVRN down 0 142
AZPS down 0 226
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April BANC down 0 130
BPAT down 0 647
CISO down 0 1,896
EPE down 0 68
IPCO down 0 209
LADWP down 0 313
NEVP down 0 469
NWMT down 0 116
PACE down 0 511
PACW down 0 196
PGE down 0 267
PNM down 0 158
PSEI down 0 262
PWRX down 0 359
SCL down 0 38
SRP down 0 200
TEPC down 0 160
TIDC down 0 19
TPWR down 0 23
WALC down 0 30
ALL EIM down 0 2,175
AVA up 4 99
May AVRN up 1 165
AZPS up 0 298
BANC up 0 103
BPAT up 3 426 CISO up 0 2,419
EPE up 0 53
IPCO up 0 155
LADWP up 0 448
NEVP up 0 478
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MPP/MA&F Copyright 2023 California ISO Page 40 of 42
NWMT up 1 131
PACE up 0 479
PACW up 0 185
PGE up 2 192
PNM up 0 165
PSEI up 0 275
PWRX up 0 303
May SCL up 0 51
SRP up 0 235
TEPC up 0 195
TIDC up 0 18
TPWR up 0 22
WALC up 0 28
ALL WEIM up 395 2,771
AVA down 0 87
AVRN down 0 142
AZPS down 0 226
BANC down 0 130
BPAT down 14 607
CISO down 20 1,896
EPE down 0 68

IPCO down 0 209
LADWP down 12 313
NEVP down 0 491
NWMT down 0 116
PACE down 0 511
PACW down 0 196
PGE down 0 269
PNM down 0 158
PSEI down 0 252
PWRX down 0 359
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MPP/MA&F Copyright 2023 California ISO Page 41 of 42
SCL down 0 38
SRP down 0 200
TEPC down 0 138
TIDC down 0 19
TPWR down 0 23
WALC down 0 29
ALL EIM down 0 2,175
June
AVA up 0 92
AVRN up 0 272
AZPS up 0 341
BANC up 0 116
BPAT up 0 462
CISO up 0 2,251
EPE up 0 75
IPCO up 6 169
LADWP up 22 432
NEVP up 0 531
NWMT up 0 127
PACE up 0 521
PACW up 0 168
PGE up 4 214
PNM up 0 170
PSEI up 0 256
PWRX up 5 291
SCL up 0 38
SRP up 0 248
TEPC up 0 295
TIDC up 0 18
TPWR up 1 24
WALC up 0 30
ALL WEIM up 385 2,771
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MPP/MA&F Copyright 2023 California ISO Page 42 of 42
June
AVA down 4 103
AVRN down 0 294
AZPS down 0 327
BANC down 0 158
BPAT down 0 597
CISO down 0 2,221
EPE down 0 70
IPCO down 0 237
LADWP down 0 382
NEVP down 0 648
NWMT down 0 129
PACE down 0 631
PACW down 9 199
PGE down 0 236
PNM down 0 243
PSEI down 11 265
PWRX down 0 359
SCL down 0 30
SRP down 0 233
TEPC down 0 148
TIDC down 0 21
TPWR down 0 20
WALC down 0 34
ALL WEIM down 0 2,175