20231120Quarterly Report.pdf

LISA O’HARA
Corporate Counsel
lo’[e-mail]

November 17, 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 third quarter of 2023. The Report presents CAISO’s quantification of benefits
associated with participation in the Western EIM. For the third quarter of 2023, CAISO estimated
Western EIM gross benefits of $8.62 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
2023 NOVEMBER 17, 2023 4:21PM
IDAHO PUBLIC
UTILITIES COMMISSION

WESTERN ENERGY IMBALANCE MARKET
BENEFITS REPORT
Third Quarter 2023

Prepared by: Market Performance and Advanced Analytics

October 31, 2023
WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 2 of 40

CONTENTS

EXECUTIVE SUMMARY ........................................................................................................ 3
BACKGROUND .................................................................................................................... 4
WEIM ECONOMIC BENEFITS IN Q3 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 .................. 36

WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 3 of 40

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.

Q3 2023 Gross Benefits by Participant
(millions $)
Arizona Public Service $19.90
AVANGRID $4.80
Avista $5.19
Balancing Authority of Northern
California $22.17
Bonneville Power Administration $6.38
California ISO $34.88
El Paso Electric $5.96
Idaho Power Company $8.62
Los Angeles Dept. of Water & Power $64.78
NV Energy $60.30
NorthWestern Energy $6.34
PacifiCorp $37.37
Portland General Electric $16.92
Public Service Company New
Mexico $8.53
Puget Sound Energy $10.06
Powerex $83.72
Seattle City Light $4.61
Salt River Project $19.10
Tacoma Power $8.19
Tucson Electric Power $7.17
Turlock Irrigation District $1.00
WAPA Desert Southwest Region $26.06
Total $462.05
Gross benefits from WEIM since November 2014
$4.66 billion
ECONOMICAL
$462.05 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
25,728
Metric tons of CO2** avoided
curtailments

OPERATIONAL
59%
Average reduction in flexibility
reserves across the footprint
2023
Q3 BENEFITS
WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 4 of 40

*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 Company 2018
Balancing Authority of Northern
California 2019
Seattle City Light 2020
Salt River Project 2020
Turlock Irrigation District 2021
Public Service Company New Mexico 2021
Los Angeles Dept. of Water & Power 2021
NorthWestern Energy 2021
Tacoma Power 2022
Avista 2022
Tucson Electric Power 2022
Bonneville Power Administration 2022
AVANGRID 2023
El Paso Electric 2023
WAPA Desert Southwest Region 2023
TABLE 1: WEIM participants

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MPP/MP&AA Copyright 2023 California ISO Page 5 of 40
WEIM ECONOMIC BENEFITS IN Q3 2023
Table 2 shows the estimated WEIM gross benefits by each region per month1. The monthly
savings presented show $171.87 million for July, $140.94 million for August and $149.24 million
for September with a total estimated benefit of $462.05 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 July August September Total
APS $10.10 $5.49 $4.31 $19.90
AVRN $2.58 $0.37 $1.85 $4.80
AVA $1.71 $1.77 $1.71 $5.19
BANC $6.17 $9.48 $6.52 $22.17
BPA $1.93 $2.61 $1.84 $6.38
CISO $16.36 $5.06 $13.46 $34.88
EPE $3.07 $1.66 $1.23 $5.96
IPCO $3.45 $3.02 $2.15 $8.62
LADWP $12.67 $17.65 $34.46 $64.78
NVE $25.32 $19.96 $15.02 $60.30
NWMT $2.36 $2.30 $1.68 $6.34
PAC $15.67 $12.98 $8.72 $37.37
PGE $5.93 $6.74 $4.25 $16.92
PNM $4.84 $2.45 $1.24 $8.53
PSE $3.44 $3.93 $2.69 $10.06
PWRX $29.50 $23.16 $31.06 $83.72
SCL $1.76 $2.00 $0.85 $4.61
SRP $5.80 $6.05 $7.25 $19.10
TPWR $2.47 $4.18 $1.54 $8.19
TEP $4.47 $1.55 $1.15 $7.17
TID $0.42 $0.31 $0.27 $1.00
WALC $11.85 $8.22 $5.99 $26.06
Total $171.87 $140.94 $149.24 $462.05
TABLE 2: Q3 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 THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 6 of 40
CUMULATIVE ECONOMIC BENEFITS SINCE INCEPTION
Since the start of the WEIM in November 2014, the cumulative economic benefits of the market
have totaled $4.66 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 THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 7 of 40
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.

WEIM BENEFITS REPORT THIRD QUARTER 2023

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GRAPH 2: WEIM transfer
WEIM BENEFITS REPORT THIRD 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

62,092

136,535

34,445
AVRN

214,898

65,970

28,245
AZPS

621,649

136,576

518,268
BANC

36,177

468,297

-
BPAT

119,588

204,114

94,270
WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 10 of 40

TABLE 3: Estimated wheel-through transfers in Q3 2023

CISO

1,594,917

845,875

1,519,554
EPE

258,984

22,139

547
IPCO

93,616

513,524

213,914
LADWP

87,844

455,981

161,045
NEVP

647,385

184,058

197,945
NWMT

60,034

46,759

53,009
PACE

900,987

271,007

171,326
PACW

139,648

215,872

407,477
PGE

63,682

324,094

71,384
PNM

236,007

79,202

94,031
PSEI

144,519

115,727

96,632
PWRX

389

1,808,142

6,762
SCL

22,880

61,630

22,255
SRP

643,065

184,906

41,429
TEPC

457,708

136,907

151,627
TIDC

35,675

26,744

-
TPWR

9,235

53,625

17,148
WALC

16,383

110,081

514,101
WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 11 of 40

GRAPH 3: Estimated wheel-through transfers in Q3 2023

BAA Net Export Net Import Wheel Through
AVA

27,950

38,627

9,301
AVRN

76,490

17,212

9,719
AZPS

234,218

28,786

173,899
BANC

17,474

127,733

-
BPAT

51,932

48,285

28,801
CISO

495,944

264,639

486,393
EPE

86,481

6,712

11
IPCO

44,837

108,245

79,206
LADWP

42,629

123,881

49,073
NEVP

242,824

67,633

67,572
NWMT

20,311

18,402

15,528
PACE

133,437

173,378

60,592
PACW

44,207

67,672

132,457
WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 12 of 40
PGE

28,141

101,627

21,160
PNM

96,399

23,274

31,074
PSEI

45,416

41,844

34,246
PWRX

340

617,515

2,872
SCL

5,986

29,929

7,454
SRP

168,163

25,228

15,347
TEPC

155,837

33,029

54,601
TIDC

13,778

8,259

-
TPWR

2,056

18,105

6,713
WALC

2,482

47,315

152,946

TABLE 4: Estimated wheel-through transfers in July 2023

GRAPH 4: Estimated wheel-through transfers in July 2023

WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 13 of 40
BAA Net Export Net Import Wheel Through
AVA

20,073

41,344

7,736
AVRN

66,780

26,230

9,605
AZPS

184,407

29,471

181,917
BANC

9,633

200,018

-
BPAT

37,016

57,318

26,757
CISO

334,312

376,646

496,054
EPE

93,845

3,648

35
IPCO

27,527

215,295

62,575
LADWP

23,570

153,200

56,810
NEVP

229,579

54,086

51,701
NWMT

21,436

14,425

16,513
PACE

444,016

24,075

43,915
PACW

56,903

57,986

146,813
PGE

22,567

106,679

31,979
PNM

84,308

15,914

30,974
PSEI

57,556

29,946

32,232
PWRX

50

491,039

1,099
SCL

8,399

16,763

7,303
SRP

175,934

73,359

3,081
TEPC

167,617

28,620

53,584
TIDC

8,370

11,463

-
TPWR

2,062

23,734

5,898
WALC

6,670

31,774

183,944

TABLE 5: Estimated wheel-through transfers in August 2023

WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 14 of 40

GRAPH 5: Estimated wheel-through transfers in August 2023

BAA Net Export Net Import Wheel Through
AVA

14,069

56,564

17,408
AVRN

71,628

22,529

8,920
AZPS

203,024

78,319

162,453
BANC

9,071

140,545

-
BPAT

30,640

98,510

38,712
CISO

764,661

204,591

537,107
EPE

78,658

11,779

501
IPCO

21,251

189,985

72,133
LADWP

21,646

178,900

55,162
NEVP

174,983

62,338

78,673
NWMT

18,287

13,932

20,969
PACE

323,533

73,554

66,819
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MPP/MP&AA Copyright 2023 California ISO Page 15 of 40
PACW

38,537

90,214

128,207
PGE

12,975

115,788

18,244
PNM

55,300

40,013

31,983
PSEI

41,547

43,938

30,154
PWRX

-

699,588

2,791
SCL

8,494

14,938

7,498
SRP

298,968

86,318

23,002
TEPC

134,254

75,259

43,442
TIDC

13,527

7,022

-
TPWR

5,117

11,786

4,537
WALC

7,231

30,992

177,210

TABLE 6: Estimated wheel-through transfers in September 2023

GRAPH 6: Estimated wheel-through transfers in September 2023
WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 16 of 40

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
Q3 2023 was calculated to be 17,760 MWh (July) + 15,406 MWh (August) + 26,947 MWh
(September) = 60,113 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 25,728 metric tons of CO2 for Q3 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
2019 2 132,937 56,897
3 33,843 14,485
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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
3 60,113 25,728
Total 2,112,850 904,219

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 THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 18 of 40
July August September
Direction Up Down Up Down Up Down
Average MW saving 1,880
2,164 1,915 2,184 1,920 2,086
Sum of BAA requirements 3,309 3,391 3,399 3,553 3,409 3,440
Percentage savings 57% 64% 56% 61% 56% 61%
Table 8: Flexible ramping procurement diversity savings in Q3 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 904,219
metric tons of CO2, roughly the equivalent of avoiding the emissions from 190,108 passenger
cars driven for one year.

WEIM BENEFITS REPORT THIRD QUARTER 2023

MPP/MP&AA Copyright 2023 California ISO Page 19 of 40
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
NWMT NorthWestern Energy
PAC PacifiCorp
PACE PacifiCorp East
PACW PacifiCorp West
PGE Portland General Electric
PNM Public Service Company of New Mexico
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: WEIM Transfer Volume (MWh)

Month

From BAA

To BAA
15min WEIM transfer
(15m – base)
5min WEIM transfer
(5m – base)
July AVA AVRN 56 88
AVA BPAT 5,256 4,959
AVA CISO 0 0
AVA IPCO 15,839 19,290
AVA NWMT 6,238 7,416
AVA PACW 4,945 5,497
AVA PGE 0 0
AVA PSEI 26 0
AVA SCL 5 0
AVA TPWR 0 0
AVRN AVA 0 4
AVRN BPAT 25,480 18,762
AVRN PACW 55,124 49,140
AVRN PGE 18,052 13,963
AVRN SCL 6,330 4,341
AZPS CISO 243,105 226,973
AZPS EPE 894 0
AZPS LADWP 26,895 29,364
AZPS NEVP 0 0
AZPS PACE 159,165 126,911
AZPS PNM 12,210 18,546
AZPS SRP 4,538 1,949
AZPS TEPC 1,494 800
AZPS WALC 3,267 3,575
BANC BPAT 0 0
BANC CISO 19,337 17,474
BANC TIDC 77 0
BPAT AVA 4,909 5,581
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BPAT AVRN 4,107 5,815
BPAT BANC 0 0
BPAT CISO 3,527 9,165
BPAT IPCO 3,740 1,687
BPAT LADWP 0 0
BPAT NEVP 0 0
BPAT NWMT 6,936 2,916
BPAT PACW 3,449 3,993
BPAT PGE 16,966 19,017
BPAT PSEI 19,110 18,625
BPAT PWRX 7,916 0
BPAT SCL 3,251 2,512
BPAT TPWR 11,629 11,421
CISO AVA 0 0
CISO AZPS 44,835 54,376
CISO BANC 117,339 127,733
July CISO BPAT 2,703 6,498
CISO LADWP 24,348 31,887
CISO NEVP 41,966 45,724
CISO PACW 9,355 31,169
CISO PGE 25,987 41,582
CISO PWRX 567,046 591,404
CISO SRP 21,075 28,376
CISO TEPC 50 198
CISO TIDC 5,841 8,259
CISO WALC 10,779 14,353
EPE AZPS 2,411 0
EPE PNM 28,419 28,813
EPE TEPC 62,678 57,679
IPCO AVA 25,693 24,009
IPCO BPAT 13,938 12,288
IPCO NEVP 21,958 17,736
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IPCO NWMT 2,777 4,609
IPCO PACE 15,850 10,290
IPCO PACW 40,061 33,517
IPCO PSEI 12,400 11,585
IPCO SCL 11,415 10,010
LADWP AZPS 793 905
LADWP BPAT 0 0
LADWP CISO 74,046 60,511
LADWP NEVP 22,951 24,685
LADWP PACE 5,748 4,650
LADWP TEPC 0 0
LADWP WALC 3,941 951
NEVP AZPS 0 0
NEVP BPAT 0 0
NEVP CISO 108,872 90,389
July NEVP IPCO 105,308 88,200
NEVP LADWP 44,630 46,193
NEVP PACE 85,556 80,721
NEVP WALC 4,519 4,894
NWMT AVA 20,275 15,451
NWMT BPAT 5,994 2,994
NWMT IPCO 5,075 6,181
NWMT PACE 14,005 11,213
NWMT PACW 88 0
NWMT PGE 83 0
NWMT PSEI 245 0
NWMT TPWR 0 0
PACE AZPS 19,555 14,740
PACE IPCO 54,555 48,055
PACE LADWP 54,750 50,053
PACE NEVP 5,675 8,546
PACE NWMT 21,346 18,989
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PACE PACW 65,191 53,646
PACE SRP 0 0
PACE TEPC 0 0
PACW AVA 3,166 2,882
PACW AVRN 9,634 17,651
PACW BPAT 4,206 2,074
PACW CISO 29,773 52,889
PACW IPCO 22,574 19,438
PACW NWMT 12 0
PACW PGE 52,865 47,271
PACW PSEI 35,975 33,173
PACW SCL 1,640 1,286
PGE AVA 0 0
PGE AVRN 986 1,750
July PGE BPAT 16,913 12,968
PGE CISO 17,993 16,435
PGE NWMT 92 0
PGE PACW 17,081 17,211
PGE PSEI 1 0
PGE SCL 1,228 937
PGE TPWR 0 0
PNM AZPS 131,039 118,573
PNM EPE 2,613 3,366
PNM SRP 2,160 2,223
PNM TEPC 3,094 3,312
PSEI AVA 124 0
PSEI BPAT 11,279 10,823
PSEI IPCO 0 0
PSEI NWMT 70 0
PSEI PACW 2,150 5,366
PSEI PGE 0 0
PSEI PWRX 32,234 28,983
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PSEI SCL 19,464 18,298
PSEI TPWR 12,421 13,398
PWRX BPAT 5,599 0
PWRX CISO 0 0
PWRX PSEI 1,648 3,212
SCL AVA 4 0
SCL AVRN 708 1,627
SCL BPAT 841 838
SCL IPCO 3,492 4,599
SCL PACW 290 592
SCL PGE 664 954
SCL PSEI 3,119 4,830
SRP AZPS 18,822 13,173
SRP CISO 155,135 146,656
July SRP PACE 0 0
SRP PNM 11 13
SRP TEPC 17,860 18,611
SRP WALC 8,862 5,055
TEPC AZPS 1,964 0
TEPC CISO 26,663 20,566
TEPC EPE 2,491 3,357
TEPC LADWP 0 0
TEPC PACE 95 186
TEPC PNM 11,448 6,976
TEPC SRP 8,422 7,919
TEPC WALC 180,771 171,433
TIDC BANC 601 0
TIDC CISO 14,033 13,778
TPWR AVA 0 0
TPWR BPAT 4,201 4,883
TPWR NWMT 0 0
TPWR PGE 0 0
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TPWR PSEI 3,753 3,887
WALC AZPS 3,896 917
WALC CISO 107,868 93,400
WALC LADWP 20,465 15,458
WALC NEVP 41,939 38,515
WALC SRP 366 108
WALC TEPC 5,742 7,030
August AVA AVRN 0 0
AVA BPAT 5,869 4,697
AVA CISO 0 0
AVA IPCO 11,503 17,567
AVA NWMT 1,924 2,275
AVA PACW 4,504 3,270
AVA PGE 147 0
AVA PSEI 0 0
AVA SCL 6 0
AVA TPWR 0 0
AVRN AVA 461 492
AVRN BPAT 28,719 20,512
AVRN PACW 46,236 39,399
AVRN PGE 17,474 12,572
AVRN SCL 5,831 3,410
AZPS CISO 256,721 272,450
AZPS EPE 1,382 0
AZPS LADWP 48,939 30,424
AZPS NEVP 0 0
AZPS PACE 71,566 33,189
AZPS PNM 6,804 8,984
AZPS SRP 20,505 17,511
AZPS TEPC 1,517 1,125
AZPS WALC 3,439 2,642
BANC BPAT 0 0
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BANC CISO 8,430 9,633
BANC TIDC 110 0
BPAT AVA 4,732 4,716
BPAT AVRN 2,111 3,199
BPAT BANC 0 0
BPAT CISO 4,438 11,023
BPAT IPCO 3,978 1,387
BPAT LADWP 0 0
BPAT NEVP 0 0
BPAT NWMT 7,533 2,835
BPAT PACW 1,756 1,331
BPAT PGE 16,308 15,670
BPAT PSEI 10,585 10,748
BPAT PWRX 5,547 0
August BPAT SCL 2,336 1,271
BPAT TPWR 12,101 11,592
CISO AVA 0 0
CISO AZPS 7,609 14,756
CISO BANC 189,869 200,018
CISO BPAT 3,417 7,354
CISO LADWP 17,565 26,702
CISO NEVP 8,462 8,417
CISO PACW 7,401 28,196
CISO PGE 21,812 33,411
CISO PWRX 428,847 458,644
CISO SRP 27,852 30,848
CISO TEPC 9 15
CISO TIDC 10,041 11,463
CISO WALC 7,035 9,615
EPE AZPS 1,410 0
EPE PNM 37,223 34,689
EPE TEPC 59,458 59,191
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IPCO AVA 28,896 19,342
IPCO BPAT 4,437 3,083
IPCO NEVP 11,260 17,844
IPCO NWMT 451 1,407
IPCO PACE 2,589 1,467
IPCO PACW 38,005 29,046
IPCO PSEI 14,100 10,121
IPCO SCL 11,344 7,794
LADWP AZPS 1,014 571
LADWP BPAT 0 0
LADWP CISO 47,987 55,524
LADWP NEVP 19,887 11,058
LADWP PACE 11,342 12,496
LADWP TEPC 0 0
August LADWP WALC 8,034 731
NEVP AZPS 0 0
NEVP BPAT 0 0
NEVP CISO 121,333 135,290
NEVP IPCO 99,608 67,488
NEVP LADWP 47,847 47,248
NEVP PACE 30,475 17,075
NEVP WALC 10,554 14,178
NWMT AVA 25,907 18,025
NWMT BPAT 8,553 6,446
NWMT IPCO 5,812 9,715
NWMT PACE 4,608 3,763
NWMT PACW 46 0
NWMT PGE 50 0
NWMT PSEI 65 0
NWMT TPWR 0 0
PACE AZPS 65,880 84,056
PACE IPCO 188,310 158,580
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PACE LADWP 87,167 92,060
PACE NEVP 36,887 42,600
PACE NWMT 31,730 24,420
PACE PACW 104,113 86,208
PACE SRP 0 0
PACE TEPC 19 6
PACW AVA 6,974 6,504
PACW AVRN 10,072 29,216
PACW BPAT 5,321 2,126
PACW CISO 16,632 41,737
PACW IPCO 18,414 18,602
PACW NWMT 0 0
PACW PGE 86,206 75,197
PACW PSEI 37,006 29,391
PACW SCL 1,497 941
August PGE AVA 4 0
PGE AVRN 556 1,021
PGE BPAT 18,030 17,274
PGE CISO 34,366 28,459
PGE NWMT 62 0
PGE PACW 5,202 7,137
PGE PSEI 33 17
PGE SCL 854 637
PGE TPWR 0 0
PNM AZPS 117,623 106,771
PNM EPE 1,005 1,663
PNM SRP 6,005 4,188
PNM TEPC 3,271 2,660
PSEI AVA 0 0
PSEI BPAT 17,944 17,192
PSEI IPCO 0 0
PSEI NWMT 34 0
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PSEI PACW 3,872 9,483
PSEI PGE 298 643
PSEI PWRX 35,670 33,494
PSEI SCL 9,410 9,987
PSEI TPWR 17,660 18,040
PWRX BPAT 6,032 0
PWRX CISO 0 0
PWRX PSEI 310 1,149
SCL AVA 16 0
SCL AVRN 850 2,398
SCL BPAT 822 785
SCL IPCO 2,563 4,531
SCL PACW 139 389
SCL PGE 866 1,165
SCL PSEI 4,065 6,434
August SRP AZPS 8,957 4,248
SRP CISO 148,736 168,057
SRP PACE 0 0
SRP PNM 3 8
SRP TEPC 5,476 4,538
SRP WALC 12,564 2,164
TEPC AZPS 1,089 0
TEPC CISO 6,780 6,710
TEPC EPE 1,245 2,020
TEPC LADWP 137 0
TEPC PACE 220 0
TEPC PNM 7,742 3,208
TEPC SRP 29,521 22,876
TEPC WALC 190,744 186,388
TIDC BANC 4,101 0
TIDC CISO 5,571 8,370
TPWR AVA 0 0
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MPP/MP&AA Copyright 2023 California ISO Page 30 of 40
TPWR BPAT 4,097 4,569
TPWR NWMT 0 0
TPWR PGE 0 0
TPWR PSEI 2,776 3,391
WALC AZPS 3,816 984
WALC CISO 120,219 134,497
WALC LADWP 24,800 13,577
WALC NEVP 41,552 25,868
WALC SRP 1,493 1,017
WALC TEPC 11,545 14,670
September AVA AVRN 0 0
AVA BPAT 20,462 12,449
AVA CISO 0 0
AVA IPCO 7,577 11,604
AVA NWMT 2,565 2,737
AVA PACW 10,315 4,688
AVA PGE 15 0
AVA PSEI 30 0
AVA SCL 3 0
AVA TPWR 0 0
AVRN AVA 3,183 3,857
AVRN BPAT 24,119 22,326
AVRN PACW 32,996 37,223
AVRN PGE 15,081 11,776
AVRN SCL 7,054 5,365
AZPS CISO 173,194 211,601
AZPS EPE 643 0
AZPS LADWP 55,622 42,243
AZPS NEVP 0 0
AZPS PACE 114,324 59,736
AZPS PNM 32,462 42,797
AZPS SRP 5,612 4,297
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AZPS TEPC 972 657
AZPS WALC 4,320 4,147
BANC BPAT 0 0
BANC CISO 6,930 9,071
BANC TIDC 84 0
BPAT AVA 4,157 5,991
BPAT AVRN 7,128 6,560
BPAT BANC 0 0
BPAT CISO 4,624 6,920
BPAT IPCO 3,850 3,402
BPAT LADWP 0 0
BPAT NEVP 0 0
BPAT NWMT 4,836 2,844
September BPAT PACW 2,451 2,170
BPAT PGE 17,402 16,124
BPAT PSEI 11,566 14,696
BPAT PWRX 7,611 0
BPAT SCL 1,195 1,327
BPAT TPWR 7,934 9,316
CISO AVA 0 0
CISO AZPS 80,461 97,171
CISO BANC 142,848 140,545
CISO BPAT 22,931 37,631
CISO LADWP 64,195 66,827
CISO NEVP 46,824 40,888
CISO PACW 16,051 59,180
CISO PGE 29,743 51,828
CISO PWRX 648,780 674,024
CISO SRP 90,085 97,995
CISO TEPC 550 320
CISO TIDC 7,075 7,022
CISO WALC 24,737 27,581
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EPE AZPS 1,529 0
EPE PNM 27,842 27,608
EPE TEPC 53,395 51,552
IPCO AVA 56,531 34,243
IPCO BPAT 17,270 12,182
IPCO NEVP 7,951 12,843
IPCO NWMT 597 1,088
IPCO PACE 3,006 2,167
IPCO PACW 35,518 19,359
IPCO PSEI 7,125 3,438
IPCO SCL 12,623 8,064
LADWP AZPS 1,875 1,032
LADWP BPAT 0 0
LADWP CISO 24,515 31,674
September LADWP NEVP 23,332 18,645
LADWP PACE 24,639 24,103
LADWP TEPC 0 0
LADWP WALC 2,997 1,354
NEVP AZPS 0 0
NEVP BPAT 0 0
NEVP CISO 38,226 56,791
NEVP IPCO 107,834 75,240
NEVP LADWP 43,938 48,676
NEVP PACE 78,091 52,210
NEVP WALC 17,424 20,737
NWMT AVA 27,166 21,752
NWMT BPAT 17,019 11,370
NWMT IPCO 2,127 3,976
NWMT PACE 2,645 2,157
NWMT PACW 35 0
NWMT PGE 56 0
NWMT PSEI 19 0
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NWMT TPWR 0 0
PACE AZPS 35,344 56,521
PACE IPCO 200,269 148,450
PACE LADWP 41,157 50,403
PACE NEVP 20,557 32,661
PACE NWMT 39,176 28,232
PACE PACW 94,698 74,072
PACE SRP 0 0
PACE TEPC 14 14
PACW AVA 5,463 8,130
PACW AVRN 20,429 20,625
PACW BPAT 7,174 6,483
September PACW CISO 6,690 21,971
PACW IPCO 11,265 15,755
PACW NWMT 0 0
PACW PGE 65,963 53,401
PACW PSEI 40,717 39,541
PACW SCL 1,023 837
PGE AVA 15 0
PGE AVRN 1,375 1,912
PGE BPAT 13,599 12,424
PGE CISO 8,736 5,910
PGE NWMT 33 0
PGE PACW 7,380 10,270
PGE PSEI 170 68
PGE SCL 636 636
PGE TPWR 0 0
PNM AZPS 78,570 73,830
PNM EPE 8,828 11,396
PNM SRP 1,361 981
PNM TEPC 1,804 1,076
PSEI AVA 0 0
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PSEI BPAT 18,419 16,787
PSEI IPCO 0 0
PSEI NWMT 65 0
PSEI PACW 10,191 11,126
PSEI PGE 0 0
PSEI PWRX 29,782 28,355
PSEI SCL 6,973 6,206
PSEI TPWR 8,192 7,007
PWRX BPAT 4,861 0
PWRX CISO 0 0
PWRX PSEI 2,440 2,791
SCL AVA 3 0
September SCL AVRN 1,351 2,351
SCL BPAT 1,250 2,223
SCL IPCO 1,685 3,689
SCL PACW 264 334
SCL PGE 868 903
SCL PSEI 4,462 6,492
SRP AZPS 27,200 11,452
SRP CISO 241,965 271,729
SRP PACE 0 0
SRP PNM 242 155
SRP TEPC 26,357 29,232
SRP WALC 22,169 9,401
TEPC AZPS 565 0
TEPC CISO 24,627 24,782
TEPC EPE 729 884
TEPC LADWP 527 0
TEPC PACE 10 0
TEPC PNM 3,364 1,435
TEPC SRP 7,136 5,611
TEPC WALC 145,492 144,983
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TIDC BANC 3,555 0
TIDC CISO 9,688 13,527
TPWR AVA 0 0
TPWR BPAT 3,649 3,347
TPWR NWMT 0 0
TPWR PGE 0 0
September TPWR PSEI 5,009 6,308
WALC AZPS 1,998 766
WALC CISO 75,956 85,503
WALC LADWP 40,643 25,912
WALC NEVP 46,566 35,973
WALC SRP 1,098 436
WALC TEPC 30,997 35,850
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APPENDIX 3: Minimum & Maximum Flexible Ramping Requirements

Month BAA Direction Minimum
requirement
Maximum
requirement
July AVA up 0 85
AVRN up 8 272
AZPS up 0 341
BANC up 0 116
BPAT up 9 462 CISO up 0 2,409
EPE up 0 75
IPCO up 0 169
LADWP up 0 384 NEVP up 0 533
NWMT up 10 131
PACE up 0 521
PACW up 0 160
PGE up 0 214
PNM up 0 170
PSEI up 0 238
PWRX up 41 274
SCL up 3 50
SRP up 0 233
TEPC up 0 186
TIDC up 0 17
TPWR up 2 25
WALC up 0 30
ALL EIM up 0 2,898
AVA down 0 103
AVRN down 17 294
AZPS down 0 327
BANC down 0 158
BPAT down 43 597
CISO down 0 2,221
EPE down 0 70
IPCO down 0 237
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LADWP down 0 391
NEVP down 0 595
NWMT down 0 129
PACE down 0 631
PACW down 0 199
PGE down 0 230
PNM down 12 243
PSEI down 6 265
PWRX down 32 325
SCL down 1 47
SRP down 0 233
TEPC down 0 136
TIDC down 0 21
TPWR down 1 21
WALC down 0 32
ALL EIM down 0 3,223
August AVA up 0 85 AVRN up 6 272
AZPS up 10 341
BANC up 0 116
BPAT up 3 462 CISO up 0 2,330
EPE up 2 75
IPCO up 25 169
LADWP up 17 405
NEVP up 0 540
NWMT up 2 131
PACE up 12 521
PACW up 0 162
PGE up 0 214
PNM up 0 170
PSEI up 0 239
PWRX up 22 333
SCL up 3 50
SRP up 32 233
TEPC up 0 186
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TIDC up 0 18
TPWR up 1 25
WALC up 4 30
ALL WEIM up 0 3,156
AVA down 0 103
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
August

IPCO down 31 237
LADWP down 23 391
NEVP down 0 601
NWMT down 0 129
PACE down 42 631
PACW down 0 199
PGE down 0 230
PNM down 21 243
PSEI down 0 265
PWRX down 0 285
SCL down 4 353
SRP down 0 233
TEPC down 0 136
TIDC down 0 21
TPWR down 0 22
WALC down 6 39
ALL EIM down 0 3,305
September

AVA up 0 85
AVRN up 0 272
AZPS up 0 341
BANC up 5 116
BPAT up 0 462
CISO up 0 2,596
EPE up 0 75
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September

IPCO up 0 169
LADWP up 0 405
NEVP up 15 540
NWMT up 0 131
PACE up 0 521
PACW up 0 153
PGE up 0 214
PNM up 10 170
PSEI up 0 256
PWRX up 0 333
SCL up 2 36
SRP up 0 221
TEPC up 0 186
TIDC up 2 18
TPWR up 2 20
WALC up 2 30
ALL WEIM up 0 3,433
AVA down 0 103
AVRN down 0 294
AZPS down 0 327
BANC down 5 158
BPAT down 0 582
CISO down 0 2,221
EPE down 1 70
IPCO down 30 237
LADWP down 0 391
NEVP down 15 648
NWMT down 3 129
PACE down 71 631
PACW down 0 199
PGE down 9 230
PNM down 19 243
PSEI down 0 265
PWRX down 0 263
SCL down 0 31
SRP down 0 233
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TEPC down 18 136
TIDC down 2 21
TPWR down 0 18
WALC down 4 39
ALL WEIM down 0 3,249