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Home My WebLink About20211109Quarterly Report.pdfJULIA A. HILTON Deputy General Counsel jhilton@idahopower.com November 9, 2021 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 and third quarters of 2021. The Report presents CAISO’s quantification of benefits associated with participation in the Western EIM. CAISO estimated Western EIM gross benefits for Idaho Power of $15.23 million for the second quarter and $17.76 million for the third quarter of 2021. 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 (208) 388-2461 or mlarkin@idahopower.com. Sincerely, Julia A. Hilton Enclosure RECEIVED 2021 NOV -9 PM 1:39 IDAHO PUBLIC UTILITIES COMMISSION www.westernEIM.com WESTERN EIM BENEFITS REPORT Second Quarter 2021 Prepared by: Market Analysis and Forecasting July 30, 2021 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 2 of 28 CONTENTS EXECUTIVE SUMMARY ........................................................................................................... 3 BACKGROUND ......................................................................................................................... 4 WESTERN EIM ECONOMIC BENEFITS IN Q2 2021 ................................................................ 4 CUMULATIVE ECONOMIC BENEFITS SINCE INCEPTION ................................................................... 5 INTER-REGIONAL TRANSFERS ............................................................................................................. 6 WHEEL THROUGH TRANSFERS .......................................................................................................... 15 REDUCED RENEWABLE CURTAILMENT AND GHG REDUCTIONS ....................................21 FLEXIBLE RAMPING PROCUREMENT DIVERSITY SAVINGS ..............................................22 CONCLUSION ..........................................................................................................................27 APPENDIX 1: GLOSSARY OF ABBREVIATIONS...................................................................28 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 3 of 28 EXECUTIVE SUMMARY This report presents the benefits associated with participation in the Western Energy Imbalance Market (EIM). The measured benefits of participation in the Western EIM 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 EIM footprint with more diverse resources and geography. Q2 2021 Gross Benefits by Participant (millions $) Arizona Public Service $9.25 BANC $18.12 California ISO $27.58 Idaho Power $15.23 LADWP $8.54 NV Energy $6.20 NorthWestern Energy $1.06 PacifiCorp $15.05 Portland General Electric $7.45 PNM $2.32 Puget Sound Energy $4.16 Powerex $1.01 Seattle City Light $2.75 Salt River Project $12.61 TID $1.37 Total $132.70 *EIM Quarterly Benefit Report Methodology: https://www.westerneim.com/Documents/EIM-BenefitMethodology.pdf. Gross benefits from EIM since November 2014 $1.42 billion ECONOMICAL $132.70 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 46,677 Metric tons of CO2** avoided curtailments OPERATIONAL 52% Average reduction in flexibility reserves across the footprint 2021 Q2 BENEFITS WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 4 of 28 **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 EIM versus dispatch that would have occurred external to the ISO without the EIM. 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). NV Energy began participating in December 2015, Arizona Public Service and Puget Sound Energy began participating in October 2016, and Portland General Electric began participating in October 2017. Idaho Power and Powerex began participating in April 2018, and the Balancing Authority of Northern California (BANC)1 began participating in April 2019. Seattle City Light and Salt River Project began participating in April 2020. Most recently, three new balancing authorities began participating in the Western EIM, with the Turlock Irrigation District (TID) in March 20212 , the second phase of BANC in March 2021, and the Los Angeles Department of Water and Power (LADWP) and Public Service Company of New Mexico (PNM) in April 2021, followed by NorthWestern Energy (NWMT) starting in June 2021. The Western EIM footprint now includes portions of Arizona, California, Idaho, Nevada, New Mexico, Oregon, Utah, Washington, Wyoming, Montana, and extends to the border with Canada. WESTERN EIM ECONOMIC BENEFITS IN Q2 2021 Table 1 shows the estimated EIM gross benefits by each region per month3. The monthly savings presented show $31.11 million for April, $30.43 million for May, and $71.16 million for June with a total estimated benefit of $132.70 million for this quarter. The increased benefits observed on June 2021 were largely driven by the heat wave in mid- June that resulted in high electric energy prices. 1 Modesto Irrigation District, the City of Redding, the City of Roseville, and the Western Area Power Administration – Sierra Nevada Region became part of the overall BANC EIM on March 25. Benefits for BANC for March 25 through March 31 are incorporated in April 2021 benefits for BANC. 2 Benefits for TID for March 25 through March 31 are incorporated in April 2021 benefits for TID. 3 The EIM 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 of the total intervals. WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 5 of 28 Region April May June Total APS $2.46 $2.61 $4.18 $9.25 BANC $5.21 $3.45 $9.46 $18.12 CISO $3.77 $4.50 $19.31 $27.58 IPCO $3.33 $3.11 $8.79 $15.23 LADWP $2.17 $2.58 $3.79 $8.54 NVE $1.52 $1.88 $2.80 $6.20 NWMT $1.06 $1.06 PAC $3.51 $3.19 $8.35 $15.05 PGE $2.69 $1.82 $2.94 $7.45 PNM $0.33 $0.68 $1.31 $2.32 PSE $1.29 $1.17 $1.70 $4.16 PWRX $0.50 $0.23 $0.28 $1.01 SCL $0.71 $0.66 $1.38 $2.75 SRP $3.20 $4.09 $5.32 $12.61 TID $0.42 $0.46 $0.49 $1.37 Total $31.11 $30.43 $71.16 $132.70 TABLE 1: Q2 2021 benefits in millions USD CUMULATIVE ECONOMIC BENEFITS SINCE INCEPTION Since the start of the EIM in November 2014, the cumulative economic benefits of the market have totaled $1.42 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 EIM benefit reports in April 2015.4 Graph 1 illustrates the gross economic benefits of the EIM by quarter for each participating BAA. 4 Prior reports are available at https://www.westerneim.com/Pages/About/QuarterlyBenefits.aspx WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 6 of 28 GRAPH 1: Cumulative economic benefits for each quarter by BAA INTER-REGIONAL TRANSFERS A significant contributor to EIM 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 EIM. 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 EIM, 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 does not quantify a BAA’s opportunity cost that the utility considered when using its transfer rights for the EIM. Table 2 provides the 15-minute and 5-minute EIM transfer volumes with base schedule transfers excluded. The EIM 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 EIM. The benefits do not include any transfers attributed to transfers submitted in the base schedules that are scheduled prior to the start of the EIM. 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 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 7 of 28 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 EIM. The 5-minute transfer volume is the result of optimization using all bids and base schedules submitted into EIM, based on unit commitments determined in the 15-minute market optimization. The maximum transfer capacities between EIM entities are shown in Graph 2 below. Month From BAA To BAA 15min EIM transfer (15m – base) 5min EIM transfer (5m – base) AZPS CISO 108,819 82,649 April AZPS LADWP 19,700 21,650 AZPS NEVP 6,129 8,467 AZPS PACE 24,536 35,027 AZPS PNM 11,340 14,805 AZPS SRP 22,461 14,092 BANC CISO 2,770 1,381 BANC TIDC 0 0 CISO AZPS 57,488 83,244 CISO BANC 163,792 181,035 CISO LADWP 73,970 87,289 CISO NEVP 91,696 109,257 CISO PACW 2,974 40,512 CISO PGE 11,271 29,855 CISO PWRX 10,604 13,383 CISO SRP 139,681 156,429 CISO TIDC 9,995 13,605 IPCO NEVP 24,537 11,946 IPCO PACE 3,767 4,814 IPCO PACW 26,101 24,934 IPCO PSEI 0 0 IPCO SCL 6,040 6,387 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 8 of 28 LADWP AZPS 681 1,449 LADWP CISO 46,638 33,441 LADWP NEVP 10,829 12,280 LADWP PACE 16,409 15,336 NEVP AZPS 924 1,189 NEVP CISO 89,801 49,410 NEVP IPCO 46,136 47,925 NEVP LADWP 28,449 22,483 NEVP PACE 31,339 35,024 PACE AZPS 80,698 56,765 PACE IPCO 92,865 91,028 PACE LADWP 14,847 11,901 PACE NEVP 64,915 38,033 PACE PACW 21,351 18,423 PACE SRP 0 0 PACW CISO 8,819 31,044 PACW IPCO 47,968 39,768 PACW PGE 37,825 32,749 PACW PSEI 17,772 23,213 PACW SCL 731 813 April PGE CISO 16,473 2 PGE PACW 37,523 43,599 PGE PSEI 9,670 13,458 PGE SCL 2,988 3,229 PNM AZPS 22,400 20,279 PNM SRP 22,383 16,383 PSEI IPCO 0 0 PSEI PACW 34,206 35,707 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 9 of 28 PSEI PGE 13,831 14,152 PSEI PWRX 17,091 18,504 PSEI SCL 24,117 23,349 PWRX CISO 11,263 6 PWRX PSEI 42,304 42,430 SCL IPCO 6,791 6,016 SCL PACW 4,175 4,206 SCL PGE 4,770 5,242 SCL PSEI 8,652 10,059 SRP AZPS 8,195 18,801 SRP CISO 129,543 120,922 SRP PACE 0 0 SRP PNM 2,487 3,785 TIDC BANC 29 84 TIDC CISO 14,316 12,159 May AZPS CISO 70,135 45,856 AZPS LADWP 25,283 30,715 AZPS NEVP 5,061 5,387 AZPS PACE 23,386 22,483 AZPS PNM 44,520 43,914 AZPS SRP 25,637 23,056 BANC CISO 9,669 5,658 BANC TIDC 0 0 CISO AZPS 117,836 125,411 CISO BANC 127,005 154,165 CISO LADWP 128,015 132,731 CISO NEVP 101,242 110,488 CISO PACW 2,153 45,620 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 10 of 28 CISO PGE 11,285 32,191 CISO PWRX 11,947 15,175 CISO SRP 191,781 203,853 CISO TIDC 17,724 19,962 IPCO NEVP 27,378 18,196 IPCO PACE 8,340 9,435 IPCO PACW 15,378 13,673 IPCO PSEI 15,528 13,553 IPCO SCL 8,109 7,795 LADWP AZPS 3,137 4,838 LADWP CISO 30,785 20,130 LADWP NEVP 12,667 12,311 LADWP PACE 68,066 63,798 NEVP AZPS 6,336 7,032 May NEVP CISO 62,718 34,254 NEVP IPCO 40,437 41,627 NEVP LADWP 66,933 57,781 NEVP PACE 39,510 38,006 PACE AZPS 111,346 101,199 PACE IPCO 103,964 94,656 PACE LADWP 34,462 31,803 PACE NEVP 105,934 80,539 PACE PACW 24,974 25,105 PACE SRP 0 0 PACW CISO 15,301 25,496 PACW IPCO 29,356 22,645 PACW PGE 28,124 29,430 PACW PSEI 20,373 24,909 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 11 of 28 PACW SCL 790 784 PGE CISO 18,572 13 PGE PACW 32,039 32,146 PGE PSEI 8,568 12,307 May PGE SCL 3,514 3,485 PNM AZPS 36,402 32,241 PNM SRP 6,387 5,628 PSEI IPCO 0 0 PSEI PACW 23,168 21,538 PSEI PGE 7,882 7,719 PSEI PWRX 16,755 16,123 PSEI SCL 20,075 22,423 PWRX CISO 19,938 44 PWRX PSEI 15,920 15,816 SCL IPCO 5,890 5,388 SCL PACW 3,989 3,846 SCL PGE 4,658 5,110 SCL PSEI 5,263 8,777 SRP AZPS 17,225 22,900 SRP CISO 87,397 80,693 SRP PACE 0 0 SRP PNM 1,509 2,429 TIDC BANC 0 0 TIDC CISO 15,007 13,005 June AZPS CISO 165,939 128,119 AZPS LADWP 29,081 24,591 AZPS NEVP 18,514 20,144 AZPS PACE 27,141 37,186 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 12 of 28 AZPS PNM 22,266 26,363 AZPS SRP 28,094 27,971 BANC CISO 15,741 13,772 BANC TIDC 55 18 CISO AZPS 36,113 40,836 CISO BANC 118,199 131,930 CISO LADWP 45,431 56,064 CISO NEVP 58,823 71,104 CISO PACW 6,195 8,783 CISO PGE 5,773 12,552 CISO PWRX 8,877 12,269 CISO SRP 63,452 70,907 CISO TIDC 15,155 17,413 IPCO NEVP 27,855 18,049 IPCO NWMT 1,328 1,635 IPCO PACE 1,396 1,940 IPCO PACW 10,642 12,254 IPCO PSEI 2,629 2,578 IPCO SCL 2,785 2,780 LADWP AZPS 5,538 8,986 LADWP CISO 95,140 76,104 LADWP NEVP 9,561 13,235 LADWP PACE 17,854 15,652 NEVP AZPS 2,546 4,592 NEVP CISO 124,249 77,570 NEVP IPCO 49,372 58,382 NEVP LADWP 20,771 24,159 NEVP PACE 23,256 25,824 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 13 of 28 NWMT IPCO 3,168 3,096 NWMT PACE 325 137 PACE AZPS 91,242 73,212 PACE IPCO 117,342 121,126 PACE LADWP 82,694 78,048 June PACE NEVP 102,997 84,127 PACE NWMT 12,982 14,388 PACE PACW 28,708 31,612 PACE SRP 0 0 PACW CISO 13,929 53,649 PACW IPCO 66,159 52,691 PACW PGE 36,093 32,552 PACW PSEI 16,009 14,581 PACW SCL 704 424 PGE CISO 11,849 0 June PGE PACW 36,936 48,387 PGE PSEI 6,445 6,464 PGE SCL 2,824 2,385 PNM AZPS 44,575 40,237 PNM SRP 9,617 8,069 PSEI IPCO 0 0 PSEI PACW 33,010 42,722 PSEI PGE 13,126 14,794 PSEI PWRX 18,707 15,462 PSEI SCL 24,940 21,561 PWRX CISO 15,829 2 PWRX PSEI 6,423 9,584 SCL IPCO 11,094 10,432 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 14 of 28 SCL PACW 4,629 7,326 SCL PGE 4,544 5,793 SCL PSEI 4,999 8,810 SRP AZPS 29,316 37,432 SRP CISO 204,531 191,172 SRP PACE 0 0 SRP PNM 800 1,343 TIDC BANC 0 119 TIDC CISO 16,965 15,428 TABLE 2: Energy transfers (MWh) in the FMM and RTD markets for Q2 2021 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 15 of 28 GRAPH 2: Estimated maximum transfer capacity (EIM entities operating in Q1 2021) WHEEL THROUGH TRANSFERS As the footprint of the Western EIM grows, wheel-through transfers may become more common. Currently, an EIM 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 Western EIM Consolidated Initiatives stakeholder process, the ISO committed to monitoring the wheel through volumes to assess whether, after the addition of new EIM 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 EIM market in the quarterly reports. In order to derive the wheel-through transfers for each EIM BAA, the ISO uses the following calculation for every real-time interval dispatch: WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 16 of 28  Total import: summation of transfers above base transfers coming into the EIM BAA under analysis  Total export: summation of all transfers above base transfers going out of the EIM 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 EIM transfers into (total import) or EIM transfer out (total export) of a BAA for a given interval All wheel-through transfers are summed over both the month and the quarter. This volume reflects the total wheel-through transfers for each EIM 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 EIM 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 AZPS 222,849 291,466 391,014 BANC 20,819 468,521 17 CISO 1,653,347 785,004 328,082 IPCO 43,479 489,356 106,908 LADWP 120,981 423,902 157,023 NEVP 162,231 250,100 364,199 NWMT 2,496 15,344 738 PACE 845,232 197,109 108,627 PACW 130,917 206,141 255,248 PGE 131,225 188,589 34,419 PNM 123,035 92,852 - PSEI 159,334 111,874 95,190 PWRX 57,999 81,019 10,049 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 17 of 28 SCL 53,373 67,837 27,788 SRP 461,302 509,306 18,757 TIDC 40,752 50,949 117 TABLE 3: Estimated wheel-through transfers in Q2 2021 GRAPH 3: Estimated wheel-through transfers in Q2 2021 BAA Net Export Net Import Wheel-Through AZPS 74,633 79,982 102,292 BANC 1,388 181,310 - CISO 597,823 213,064 118,415 IPCO 14,024 150,828 34,194 LADWP 37,687 118,563 24,994 NEVP 50,536 74,530 105,713 NWMT - - - PACE 199,366 73,529 16,949 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 18 of 28 PACW 34,706 74,522 93,090 PGE 47,741 69,533 12,590 PNM 36,713 18,611 - PSEI 49,001 46,416 42,879 PWRX 37,111 26,480 5,428 SCL 17,338 25,598 8,243 SRP 131,186 174,927 12,563 TIDC 12,252 13,614 - TABLE 4: Estimated wheel-through transfers in April 2021 GRAPH 4: Estimated wheel-through transfers in April 2021 BAA Net Export Net Import Wheel- Through AZPS 32,204 154,930 139,474 BANC 5,658 154,424 - CISO 743,797 127,282 98,075 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 19 of 28 IPCO 19,397 121,086 43,327 LADWP 20,388 172,772 80,815 NEVP 40,133 88,338 138,716 NWMT - - - PACE 269,730 70,642 63,693 PACW 39,013 77,186 64,969 PGE 34,830 61,566 13,177 PNM 37,877 46,452 - PSEI 34,866 42,462 33,042 PWRX 12,679 28,135 3,213 SCL 14,866 26,318 8,269 SRP 104,791 231,693 1,491 TIDC 13,031 19,975 - TABLE 5: Estimated wheel-through transfers in May 2021 GRAPH 5: Estimated wheel-through transfers in May 2021 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 20 of 28 BAA Net Export Net Import Wheel Through AZPS 116,013 56,554 149,247 BANC 13,773 132,787 17 CISO 311,727 444,659 111,592 IPCO 10,058 217,442 29,387 LADWP 62,906 132,567 51,215 NEVP 71,561 87,232 119,770 NWMT 2,496 15,344 738 PACE 376,136 52,938 27,985 PACW 57,198 54,434 97,189 PGE 48,654 57,490 8,652 PNM 48,445 27,788 - PSEI 75,467 22,996 19,268 PWRX 8,209 26,404 1,408 SCL 21,168 15,920 11,276 SRP 225,325 102,687 4,703 TIDC 15,469 17,361 117 TABLE 6: Estimated wheel-through transfers in June 2021 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 21 of 28 GRAPH 6: Estimated wheel-through transfers in June 2021 REDUCED RENEWABLE CURTAILMENT AND GHG REDUCTIONS The Western EIM 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 EIM, 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 2021 was calculated to be 49,173 MWh (April) + 43,119 MWh (May) + 16,767 MWh (June) = 109,059 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 46,677 metric tons of CO2 for Q2 2021. 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 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 22 of 28 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 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 Total 1,509,114 645,821 TABLE 7: Total reduction in curtailment of renewable energy and associated reductions in CO2 FLEXIBLE RAMPING PROCUREMENT DIVERSITY SAVINGS The Western EIM 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 EIM footprint can be less than the sum of individual BAA’s requirements. This difference is known as flexible ramping procurement diversity savings. WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 23 of 28 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 Table 8. Month BAA Direction Minimum requirement Maximum requirement AZPS up 0 292 April BANC up 0 113 CISO up 0 1955 IPCO up 0 212 LADWP up 0 241 NEVP up 0 275 PACE up 0 328 PACW up 0 181 PGE up 0 310 PNM up 0 162 PSEI up 0 177 PWRX up 0 282 SCL up 0 52 SRP up 0 136 TIDC up 0 15 ALL EIM up 0 2,734 AZPS down 0 292 BANC down 0 119 CISO down 0 1,361 IPCO down 0 224 LADWP down 0 171 NEVP down 0 272 April PACE down 0 407 PACW down 0 157 PGE down 0 234 PNM down 0 164 PSEI down 0 144 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 24 of 28 PWRX down 0 268 SCL down 0 43 SRP down 0 161 TIDC down 0 18 ALL EIM down 0 1,807 AZPS up 34 292 May BANC up 7 80 CISO up 113 1,824 IPCO up 26 229 LADWP up 31 241 NEVP up 27 275 PACE up 104 328 PACW up 60 181 PGE up 72 310 PNM up 35 158 PSEI up 36 177 PWRX up 69 278 SCL up 5 52 SRP up 37 148 TIDC up 1 15 ALL EIM up 101 2,563 AZPS down 34 292 BANC down 0 119 CISO down 226 1,361 May IPCO down 54 224 LADWP down 23 171 NEVP down 22 277 PACE down 121 407 PACW down 29 157 PGE down 45 234 PNM down 32 164 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 25 of 28 PSEI down 27 154 PWRX down 69 268 SCL down 0 38 SRP down 16 159 TIDC down 1 18 ALL EIM down 272 1,807 June AZPS up 32 294 BANC up 6 73 CISO up 321 2,059 IPCO up 31 229 LADWP up 34 359 NEVP up 37 303 NWMT up 36 83 PACE up 66 541 PACW up 54 181 PGE up 67 310 PNM up 34 227 PSEI up 30 150 PWRX up 69 219 SCL up 4 32 SRP up 23 160 TIDC up 2 15 ALL EIM up 323 2,260 AZPS down 30 288 BANC down 2 96 CISO down 98 1,631 IPCO down 38 246 LADWP down 29 191 NEVP down 34 282 NWMT down 24 100 PACE down 121 581 WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 26 of 28 PACW down 14 159 PGE down 39 244 PNM down 48 196 PSEI down 37 154 PWRX down 69 229 SCL down 1 29 SRP down 18 178 TIDC down 2 12 ALL EIM down 196 1,807 Table 8: Flexible ramping requirements The flexible ramping procurement diversity savings for all the intervals averaged over the month are shown in Table 9. The percentage savings is the average MW savings divided by the sum of the four individual BAA requirements. April May June Direction Up Down Up Down Up Down Average MW saving 1,168 1,179 1,110 1,145 1,206 1,305 Sum of BAA requirements 2,437 2,187 2,278 2,142 2,399 2,172 Percentage savings 48% 54% 49% 53% 50% 60% Table 9: Flexible ramping procurement diversity savings in Q2 2021 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 EIM-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 EIM 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 EIM dispatch cost to reflect the true dispatch cost of a BAA. Please see the Benefit Report Methodology for more details. WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 27 of 28 CONCLUSION Using state-of-the-art technology to find and deliver low-cost energy to meet real-time demand, the Western EIM demonstrates that utilities can realize financial and operational benefits through increased coordination and optimization. In addition to these benefits, the Western EIM 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 645,821 metric tons of CO2, roughly the equivalent of avoiding the emissions from 135,781 passenger cars driven for one year. WESTERN EIM BENEFITS REPORT SECOND QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 28 of 28 APPENDIX 1: GLOSSARY OF ABBREVIATIONS Abbreviation Description APS Arizona Public Service BAA Balancing Authority Area BANC Balancing Authority of Northern California CISO, ISO California ISO EIM Energy Imbalance Market FMM Fifteen Minute Market GHG Greenhouse Gas IPCO Idaho 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 TID Turlock Irrigation District www.westernEIM.com WESTERN EIM BENEFITS REPORT Third Quarter 2021 Prepared by: Market Analysis and Forecasting October 29, 2021 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 2 of 29 CONTENTS EXECUTIVE SUMMARY ........................................................................................................... 3 BACKGROUND ......................................................................................................................... 4 WESTERN EIM ECONOMIC BENEFITS IN Q3 2021 ................................................................ 4 CUMULATIVE ECONOMIC BENEFITS SINCE INCEPTION ................................................................... 5 INTER-REGIONAL TRANSFERS ............................................................................................................. 6 WHEEL THROUGH TRANSFERS .......................................................................................................... 16 REDUCED RENEWABLE CURTAILMENT AND GHG REDUCTIONS ....................................22 FLEXIBLE RAMPING PROCUREMENT DIVERSITY SAVINGS ..............................................24 CONCLUSION ..........................................................................................................................28 APPENDIX 1: GLOSSARY OF ABBREVIATIONS...................................................................29 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 3 of 29 EXECUTIVE SUMMARY This report presents the benefits associated with participation in the Western Energy Imbalance Market (EIM). The measured benefits of participation in the Western EIM 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 EIM footprint with more diverse resources and geography. Q3 2021 Gross Benefits by Participant (millions $) Arizona Public Service $24.58 BANC $72.52 California ISO $54.01 Idaho Power $17.76 LADWP $23.57 NV Energy $18.04 NorthWestern Energy $5.16 PacifiCorp $40.12 Portland General Electric $7.12 PNM $6.77 Puget Sound Energy $6.78 Powerex $0.92 Seattle City Light $3.92 Salt River Project $17.78 TID $2.13 Total $301.18 *EIM Quarterly Benefit Report Methodology: https://www.westerneim.com/Documents/EIM-BenefitMethodology.pdf. Gross benefits from EIM since November 2014 $1.72 billion ECONOMICAL $301.18 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 9,862 Metric tons of CO2** avoided curtailments OPERATIONAL 56% Average reduction in flexibility reserves across the footprint 2021 Q3 BENEFITS WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 4 of 29 **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 EIM versus dispatch that would have occurred external to the ISO without the EIM. 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). NV Energy began participating in December 2015, Arizona Public Service and Puget Sound Energy began participating in October 2016, and Portland General Electric began participating in October 2017. Idaho Power and Powerex began participating in April 2018, and the Balancing Authority of Northern California (BANC) began participating in April 2019. Seattle City Light and Salt River Project began participating in April 2020. Most recently, three new balancing authorities began participating in the Western EIM, with the Turlock Irrigation District (TID) in March 2021, the second phase of BANC in March 2021, and the Los Angeles Department of Water and Power (LADWP) and Public Service Company of New Mexico (PNM) in April 2021, followed by NorthWestern Energy (NWMT) starting in June 2021. The Western EIM footprint now includes portions of Arizona, California, Idaho, Nevada, New Mexico, Oregon, Utah, Washington, Wyoming, Montana, and extends to the border with Canada. WESTERN EIM ECONOMIC BENEFITS IN Q3 2021 Table 1 shows the estimated EIM gross benefits by each region per month1. The monthly savings presented show $129.10 million for July, $78.57 million for August, and $93.51 million for September with a total estimated benefit of $301.18 million for this quarter. The increased benefits observed in Q3 2021 were largely driven by the heat waves resulting in high loads and tight supply conditions across the EIM footprint. These conditions resulted in high electric energy prices. 1 The EIM 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 of the total intervals. WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 5 of 29 Region July August September Total APS $10.16 $6.62 $7.80 $24.58 BANC $26.62 $17.75 $28.15 $72.52 CISO $29.80 $15.19 $9.02 $54.01 IPCO $9.59 $4.20 $3.97 $17.76 LADWP $9.85 $5.67 $8.05 $23.57 NVE $7.44 $3.08 $7.52 $18.04 NWMT $1.53 $2.25 $1.38 $5.16 PAC $14.10 $10.95 $15.07 $40.12 PGE $2.67 $2.32 $2.13 $7.12 PNM $3.29 $1.45 $2.03 $6.77 PSE $2.32 $2.70 $1.76 $6.78 PWRX $0.61 $0.23 $0.08 $0.92 SCL $1.79 $1.08 $1.05 $3.92 SRP $8.54 $4.51 $4.73 $17.78 TID $0.79 $0.57 $0.77 $2.13 Total $129.10 $78.57 $93.51 $301.18 TABLE 1: Q3 2021 benefits in millions USD CUMULATIVE ECONOMIC BENEFITS SINCE INCEPTION Since the start of the EIM in November 2014, the cumulative economic benefits of the market have totaled $1.72 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 EIM benefit reports in April 2015.2 Graph 1 illustrates the gross economic benefits of the EIM by quarter for each participating BAA. 2 Prior reports are available at https://www.westerneim.com/Pages/About/QuarterlyBenefits.aspx WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 6 of 29 GRAPH 1: Cumulative economic benefits for each quarter by BAA INTER-REGIONAL TRANSFERS A significant contributor to EIM 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 EIM. 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 EIM, 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 does not quantify a BAA’s opportunity cost that the utility considered when using its transfer rights for the EIM. Table 2 provides the 15-minute and 5-minute EIM transfer volumes with base schedule transfers excluded. The EIM 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 EIM. The benefits do not include any transfers attributed to transfers submitted in the base schedules that are scheduled prior to the start of the EIM. 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 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 7 of 29 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 EIM. The 5-minute transfer volume is the result of optimization using all bids and base schedules submitted into EIM, based on unit commitments determined in the 15-minute market optimization. The maximum transfer capacities between EIM entities are shown in Graph 2 below. Month From BAA To BAA 15min EIM transfer (15m – base) 5min EIM transfer (5m – base) AZPS CISO 296,277 265,859 July AZPS LADWP 29,718 31,143 AZPS NEVP 17,900 24,961 AZPS PACE 10,875 15,755 AZPS PNM 9,804 13,527 AZPS SRP 14,246 14,318 BANC CISO 15,648 12,316 BANC TIDC 36 25 CISO AZPS 6,782 9,387 CISO BANC 118,099 135,441 CISO LADWP 16,958 23,611 CISO NEVP 11,345 15,299 CISO PACW 7,332 5,605 CISO PGE 5,243 5,957 CISO PWRX 7,305 8,980 CISO SRP 10,776 13,081 CISO TIDC 9,625 11,829 IPCO NEVP 52,278 39,174 IPCO NWMT 4,829 5,758 IPCO PACE 1,195 1,621 IPCO PACW 11,291 14,523 IPCO PSEI 7,329 7,578 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 8 of 29 IPCO SCL 6,148 6,281 LADWP AZPS 834 1,299 LADWP CISO 165,437 139,638 LADWP NEVP 17,924 21,917 LADWP PACE 8,888 9,487 NEVP AZPS 874 1,265 NEVP CISO 197,892 151,613 NEVP IPCO 26,591 36,681 NEVP LADWP 22,284 24,816 NEVP PACE 1,615 3,364 NWMT IPCO 9,233 9,682 NWMT PACE 994 1,029 NWMT PACW 0 0 NWMT PGE 0 0 NWMT PSEI 0 0 PACE AZPS 66,206 59,241 PACE IPCO 155,963 164,174 PACE LADWP 98,545 91,710 PACE NEVP 108,264 97,329 PACE NWMT 16,227 21,082 July PACE PACW 43,205 53,664 PACE SRP 0 0 PACW CISO 10,981 53,300 PACW IPCO 39,220 33,284 PACW NWMT 0 0 PACW PGE 63,670 61,182 PACW PSEI 26,167 25,092 PACW SCL 1,116 932 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 9 of 29 PGE CISO 16,884 26 PGE NWMT 0 0 PGE PACW 21,384 29,994 PGE PSEI 366 499 PGE SCL 1,090 930 PNM AZPS 83,660 77,220 PNM SRP 0 0 PSEI IPCO 0 0 PSEI NWMT 0 0 PSEI PACW 39,905 44,507 PSEI PGE 1,998 2,243 PSEI PWRX 15,718 13,346 PSEI SCL 27,457 25,181 PWRX CISO 14,981 85 PWRX PSEI 10,847 12,860 SCL IPCO 9,869 9,709 SCL PACW 926 1,234 SCL PGE 1,449 1,693 SCL PSEI 6,450 9,746 SRP AZPS 14,307 16,895 SRP CISO 280,825 273,569 SRP PACE 0 0 SRP PNM 38 55 TIDC BANC 3,421 2,579 TIDC CISO 19,861 17,487 August AZPS CISO 272,766 250,526 AZPS LADWP 43,125 45,810 AZPS NEVP 23,072 25,476 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 10 of 29 AZPS PACE 8,249 9,691 AZPS PNM 10,097 15,078 AZPS SRP 34,945 33,638 BANC CISO 19,767 17,202 BANC TIDC 3 0 CISO AZPS 11,274 16,698 CISO BANC 94,172 106,328 CISO LADWP 22,637 30,664 CISO NEVP 12,370 14,801 CISO PACW 8,035 11,691 CISO PGE 3,242 16,176 CISO PWRX 9,358 10,811 CISO SRP 43,344 48,267 CISO TIDC 14,096 15,376 IPCO NEVP 52,108 40,166 IPCO NWMT 559 969 IPCO PACE 801 769 IPCO PACW 45,198 49,679 IPCO PSEI 9,771 9,351 IPCO SCL 6,690 6,428 LADWP AZPS 1,046 1,094 LADWP CISO 136,099 110,843 LADWP NEVP 15,199 18,520 LADWP PACE 9,785 9,142 August NEVP AZPS 1,056 823 NEVP CISO 153,696 123,993 NEVP IPCO 26,805 32,311 NEVP LADWP 34,822 36,531 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 11 of 29 NEVP PACE 989 876 NWMT IPCO 23,425 24,674 NWMT PACE 2,462 1,766 NWMT PACW 0 0 NWMT PGE 0 0 NWMT PSEI 0 0 PACE AZPS 110,864 93,052 PACE IPCO 202,096 203,495 PACE LADWP 98,262 93,735 PACE NEVP 138,027 125,513 PACE NWMT 11,359 13,669 PACE PACW 30,208 35,228 PACE SRP 0 0 PACW CISO 21,266 45,505 August PACW IPCO 35,964 27,071 PACW NWMT 0 0 PACW PGE 67,960 64,600 PACW PSEI 24,388 21,668 PACW SCL 1,025 789 PGE CISO 7,744 16 PGE NWMT 0 0 PGE PACW 24,706 31,825 PGE PSEI 0 0 PGE SCL 1,041 932 PNM AZPS 66,998 58,505 PNM SRP 0 0 PSEI IPCO 0 0 PSEI NWMT 0 0 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 12 of 29 PSEI PACW 35,660 41,681 PSEI PGE 0 0 PSEI PWRX 14,825 14,057 PSEI SCL 24,936 22,877 PWRX CISO 15,144 4 PWRX PSEI 10,004 11,502 SCL IPCO 7,613 8,334 SCL PACW 839 1,212 SCL PGE 1,454 1,639 SCL PSEI 5,362 7,207 SRP AZPS 59,661 60,669 SRP CISO 144,196 140,815 SRP PACE 0 0 SRP PNM 0 0 TIDC BANC 212 0 TIDC CISO 19,526 18,438 September AZPS CISO 199,062 182,791 AZPS LADWP 24,469 24,737 AZPS NEVP 7,744 9,400 AZPS PACE 5,603 7,477 AZPS PNM 20,547 28,473 AZPS SRP 35,525 35,158 BANC CISO 9,846 6,517 BANC TIDC 7 44 CISO AZPS 13,172 14,844 CISO BANC 141,187 149,532 CISO LADWP 31,147 35,925 CISO NEVP 17,619 20,401 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 13 of 29 CISO PACW 2,122 16,392 CISO PGE 5,584 21,727 CISO PWRX 36,744 11,809 CISO SRP 41,465 52,045 CISO TIDC 21,931 23,409 IPCO NEVP 109,382 103,947 IPCO NWMT 349 429 IPCO PACE 902 963 IPCO PACW 25,919 24,928 IPCO PSEI 16,547 15,564 IPCO SCL 7,541 6,932 LADWP AZPS 5,841 6,630 LADWP CISO 146,716 123,433 LADWP NEVP 9,958 9,914 LADWP PACE 7,221 9,479 NEVP AZPS 5,363 5,825 NEVP CISO 200,648 177,095 NEVP IPCO 13,248 14,905 NEVP LADWP 35,626 41,213 NEVP PACE 2,607 4,250 NWMT IPCO 20,137 21,320 NWMT PACE 3,625 3,483 NWMT PACW 29 14 NWMT PGE 9 12 NWMT PSEI 4 2 September PACE AZPS 112,443 108,763 PACE IPCO 149,496 161,367 PACE LADWP 90,477 86,042 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 14 of 29 PACE NEVP 121,678 112,794 PACE NWMT 6,203 6,801 PACE PACW 21,531 23,293 PACE SRP 0 0 PACW CISO 11,929 25,588 PACW IPCO 6,390 4,125 PACW NWMT 0 4 September PACW PGE 64,497 60,642 PACW PSEI 21,096 17,362 PACW SCL 426 338 PGE CISO 13,593 171 PGE NWMT 23 15 PGE PACW 18,180 25,031 PGE PSEI 0 0 PGE SCL 349 326 PNM AZPS 45,351 38,596 PNM SRP 0 8 PSEI IPCO 0 0 PSEI NWMT 0 1 PSEI PACW 0 0 PSEI PGE 0 0 PSEI PWRX 16,592 17,154 PSEI SCL 17,213 17,291 PWRX CISO 15,544 171 PWRX PSEI 8,848 9,254 SCL IPCO 7,818 8,969 SCL PACW 1,116 1,269 SCL PGE 1,374 1,464 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 15 of 29 TABLE 2: Energy transfers (MWh) in the FMM and RTD markets for Q3 2021 GRAPH 2: Estimated maximum transfer capacity (EIM entities operating in Q3 2021) SCL PSEI 9,367 11,227 SRP AZPS 12,695 13,803 SRP CISO 155,763 153,947 SRP PACE 0 0 SRP PNM 295 527 TIDC BANC 8 44 TIDC CISO 10,888 9,299 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 16 of 29 WHEEL THROUGH TRANSFERS As the footprint of the Western EIM grows, wheel-through transfers may become more common. Currently, an EIM 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 Western EIM Consolidated Initiatives stakeholder process, the ISO committed to monitoring the wheel through volumes to assess whether, after the addition of new EIM 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 EIM market in the quarterly reports. In order to derive the wheel-through transfers for each EIM BAA, the ISO uses the following calculation for every real-time interval dispatch:  Total import: summation of transfers above base transfers coming into the EIM BAA under analysis  Total export: summation of all transfers above base transfers going out of the EIM 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 EIM transfers into (total import) or EIM transfer out (total export) of a BAA for a given interval All wheel-through transfers are summed over both the month and the quarter. This volume reflects the total wheel-through transfers for each EIM 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 EIM 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 AZPS 569,120 118,075 468,090 BANC 36,316 394,711 45 CISO 376,087 1,836,395 471,210 IPCO 61,682 487,517 274,213 LADWP 277,753 382,761 184,701 NEVP 241,823 265,294 416,010 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 17 of 29 NWMT 59,122 45,981 2,913 PACE 1,491,075 15,765 63,798 PACW 176,643 146,472 266,305 PGE 81,027 228,790 9,014 PNM 174,753 57,750 14 PSEI 137,017 97,415 61,839 PWRX 29,236 71,572 4,746 SCL 37,863 63,425 25,989 SRP 656,167 190,960 5,763 TIDC 47,875 50,676 122 TABLE 3: Estimated wheel-through transfers in Q3 2021 GRAPH 3: Estimated wheel-through transfers in Q3 2021 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 18 of 29 BAA Net Export Net Import Wheel-Through AZPS 228,581 28,086 137,746 BANC 12,387 138,453 0 CISO 79,217 765,957 150,414 IPCO 14,479 193,474 60,686 LADWP 115,077 113,960 57,655 NEVP 100,800 81,569 117,622 NWMT 10,670 26,911 49 PACE 465,824 8,423 22,858 PACW 68,764 44,579 105,488 PGE 29,365 68,901 2,220 PNM 77,312 13,651 - PSEI 59,621 29,951 25,920 PWRX 11,498 20,838 1,508 SCL 14,022 24,977 8,410 SRP 291,269 27,417 - TIDC 20,058 11,795 81 TABLE 4: Estimated wheel-through transfers in July 2021 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 19 of 29 GRAPH 4: Estimated wheel-through transfers in July 2021 BAA Net Export Net Import Wheel- Through AZPS 196,446 45,986 185,470 BANC 17,409 106,441 - CISO 124,056 563,565 146,994 IPCO 10,016 198,873 97,539 LADWP 73,582 140,984 66,510 NEVP 72,457 102,222 122,811 NWMT 25,718 13,928 742 PACE 546,801 3,238 19,038 PACW 50,341 61,830 109,874 PGE 30,948 80,716 1,964 PNM 58,818 15,078 - PSEI 58,677 29,712 20,148 PWRX 9,911 23,329 1,630 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 20 of 29 SCL 10,854 23,518 7,586 SRP 196,641 76,356 5,575 TIDC 18,509 15,407 - TABLE 5: Estimated wheel-through transfers in August 2021 GRAPH 5: Estimated wheel-through transfers in August 2021 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 21 of 29 BAA Net Export Net Import Wheel Through AZPS 144,092 44,003 144,874 BANC 6,520 149,817 45 CISO 172,814 506,873 173,802 IPCO 37,187 95,170 115,988 LADWP 89,094 127,816 60,536 NEVP 68,565 81,502 175,577 NWMT 22,734 5,142 2,122 PACE 478,450 4,104 21,902 PACW 57,538 40,063 50,943 PGE 20,713 79,172 4,830 PNM 38,623 29,021 14 PSEI 18,719 37,752 15,771 PWRX 7,827 27,405 1,608 SCL 12,987 14,930 9,992 SRP 168,258 87,186 188 TIDC 9,309 23,474 41 TABLE 6: Estimated wheel-through transfers in September 2021 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 22 of 29 GRAPH 6: Estimated wheel-through transfers in September 2021 REDUCED RENEWABLE CURTAILMENT AND GHG REDUCTIONS The Western EIM 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 EIM, 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 2021 was calculated to be 4,491 MWh (July) + 7,099 MWh (August) + 11,451 MWh (September) = 23,042 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 9,862 metric tons of CO2 for Q3 2021. 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 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 23 of 29 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 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 Total 1,532,156 655,683 TABLE 7: Total reduction in curtailment of renewable energy and associated reductions in CO2 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 24 of 29 FLEXIBLE RAMPING PROCUREMENT DIVERSITY SAVINGS The Western EIM 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 EIM 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 Table 8. Month BAA Direction Minimum requirement Maximum requirement AZPS up 35 319 July BANC up 6 81 CISO up 400 2,059 IPCO up 35 256 LADWP up 45 359 NEVP up 41 303 NWMT up 32 83 PACE up 115 541 PACW up 44 203 PGE up 69 220 PNM up 53 227 PSEI up 31 151 PWRX up 58 258 SCL up 4 34 SRP up 23 160 TIDC up 1 16 ALL EIM up 589 2,239 AZPS down 4 299 BANC down 4 118 CISO down 0 1,631 IPCO down 39 239 LADWP down 39 218 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 25 of 29 NEVP down 14 285 NWMT down 25 100 PACE down 146 581 PACW down 44 159 PGE down 36 244 PNM down 54 212 July PSEI down 33 137 PWRX down 74 238 SCL down 4 34 SRP down 20 191 TIDC down 2 14 ALL EIM down 0 1,775 AZPS up 41 319 August BANC up 7 83 CISO up 505 2,068 IPCO up 33 256 LADWP up 40 359 NEVP up 57 303 NWMT up 32 83 PACE up 100 541 PACW up 42 203 PGE up 67 273 PNM up 47 227 PSEI up 35 151 PWRX up 64 258 SCL up 3 34 SRP up 45 160 TIDC up 2 16 ALL EIM up 669 2,541 AZPS down 5 299 BANC down 6 118 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 26 of 29 CISO down 16 1,310 August IPCO down 23 247 LADWP down 29 218 NEVP down 13 285 NWMT down 25 212 PACE down 121 581 PACW down 43 159 PGE down 36 216 PNM down 40 212 PSEI down 30 137 PWRX down 74 251 SCL down 3 41 SRP down 20 247 TIDC down 2 14 ALL EIM down 8 1,639 September AZPS up 31 335 BANC up 5 89 CISO up 428 2,669 IPCO up 38 256 LADWP up 44 230 NEVP up 41 360 NWMT up 26 141 PACE up 109 568 PACW up 25 203 PGE up 57 273 PNM up 46 227 PSEI up 28 160 PWRX up 64 228 SCL up 3 34 SRP up 44 210 TIDC up 3 14 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 27 of 29 September ALL EIM up 655 2,917 AZPS down 33 403 BANC down 9 118 CISO down 93 1,057 IPCO down 11 239 LADWP down 23 269 NEVP down 21 580 NWMT down 38 173 PACE down 157 591 PACW down 48 181 PGE down 39 215 PNM down 41 218 PSEI down 38 180 PWRX down 85 300 SCL down 3 41 SRP down 19 382 TIDC down 2 14 ALL EIM down 66 1,633 Table 8: Flexible ramping requirements The flexible ramping procurement diversity savings for all the intervals averaged over the month are shown in Table 9. The percentage savings is the average MW savings divided by the sum of the four individual BAA requirements. July August September Direction Up Down Up Down Up Down Average MW saving 1,317 1,442 1,326 1,461 1,255 1,385 Sum of BAA requirements 2,611 2,267 2,626 2,323 2,580 2,248 Percentage savings 50% 64% 50% 63% 49% 62% Table 9: Flexible ramping procurement diversity savings in Q3 2021 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 WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 28 of 29 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 EIM-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 EIM 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 EIM 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 Western EIM demonstrates that utilities can realize financial and operational benefits through increased coordination and optimization. In addition to these benefits, the Western EIM 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 655,683 metric tons of CO2, roughly the equivalent of avoiding the emissions from 137,854 passenger cars driven for one year. WESTERN EIM BENEFITS REPORT THIRD QUARTER 2021 MPP/MA&F Copyright 2021 California ISO Page 29 of 29 APPENDIX 1: GLOSSARY OF ABBREVIATIONS Abbreviation Description APS Arizona Public Service BAA Balancing Authority Area BANC Balancing Authority of Northern California CISO, ISO California ISO EIM Energy Imbalance Market 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 North West Energy PAC PacifiCorp PACE PacifiCorp East PACW PacifiCorp West PNM Public Service Company of New Mexico PGE Portland General Electric PSE Puget Sound Energy PWRX Powerex RTD Real Time Dispatch SCL Seattle City Light SRP Salt River Project TID Turlock Irrigation District