Executive Summary
The purpose of this report is to provide market participants a monthly summary of day-ahead and real-time markets performance for August, 2025. The key market performance highlights are presented here:
CAISO area performance:
Peak loads for ISO area decreased slightly in October compared to the previous month possibly due to lower temperature.
The cumulative total congestion rent for interties decreased from $0.346 million in September to \0.216 million in October. Majority of the congestion rents in October accrued on IPPUTAH_ITC(100%). Congestion rents on the MALIN500_ISL and NOB_ITC interties declined from $155,565 and $92,411 in September, respectively, to zero in October, while the congestion rent on IPPUTAH_ITC rose from $97,881 to $216,430 over the same period.
Average Day-Ahead DLAP prices in PGAE decreased relative to the previous month, aligning with the load reduction. Similar pattern were observed in both FMM and RTD.
Net Monthly Balancing Surplus in October was $1.37 million. The auction revenues credited to the balancing account for October were $6.72 million. As a result, the balancing account had a surplus of approximately $8.09 million compared to $9.78 million in the previous month, which was allocated to measured demand.
In September the monthly IFM average procurement increased for regulation up and regulation down, while decreased for spinning and non-spinning reserves compared to the previous month. The monthly IFM average prices decreased for regulation down, non-spinning reserves, regulation up, spinning reserves compared to the previous month.
The total bid cost recovery decreased from $12.3 million in September to $10.4 million in October. Out of the total monthly bid cost recovery payment for the three markets in October, the IFM market contributed 26.4 percent, RUC contributed 51.8 percent, and RTM contributed 21.8 percent of the total bid cost recovery payment.
RTIEO increased from -$8.6 million in September to -$3.07 million in October. RTCO decreased from $28.5 million in September to $16 million in October.
The monthly uplift payments decreased from $443,880 in September to $426,266 in October. Uplift payment was mainly caused by planned transmission outages in this month.
The number of market disruptions remained at 38 from September to October. On October 31, there were 9 (3 FMM and 6 RTD) disruptions due to implementation of a market software patch. On October 21, there were 6 (6 RTD) interval disruptions due to implementation of a market software patch.
The total volume of exceptional dispatch increased from 49,694 MWh in September to 111,869 MWh in October. There was a spike on October 26 due to voltage support needs.
The curtailment of renewable energy increased in October compared to the previous month. Most curtailments continued to be solar.
Western Energy Imbalance Market (WEIM) performance:
The FMM ELAP prices in September decreased for most of BAA, except BCHA, BPAT. Besides, FMM ELAP prices were similarly volatile compared to the previous month. The RTD ELAP prices in September increased for AVA, AVRN, BCHA, BPAT, PACW, PGE, and decreased for AZPS, BANC, EPE, IPCO,LADWP,NEVP,NWMT, PACE, PNM, PSEI,SRP,SCL,TIDC, TPWR, TEPC, WALC. And RTD ELAP prices were similarly volatile compared to the previous month.
The monthly average ELAP prices in FMM and RTD for WEIM entities and the difference between the two (FMM minus RTD) are shown in Table 0.1 below.
The cumulative frequency of FMM ELAP prices above $250/MWh increased from 0.0584 percent in September to 0.0779 percent in October. The cumulative frequency of negative FMM ELAP prices increased from 0.426 percent in September to 3.59 percent in October. The cumulative frequency of RTD ELAP prices above $250/MWh increased from 0.0526 percent in September to 0.0082 percent in October. The cumulative frequency of RTD ELAP negative prices increased from 0.621 percent in September to 4.45 percent in October.
Total WEIM RTIEO increased from $0.371 million in September to $2.06 million in October. Total WEIM RTCO decreased from -$6.07 million in September to -$7.6 million in October.
Total WEIM BCR decreased from $1.46 million in September to $0.755 million in October.
Total flexible ramping up uncertainty payment increased from $0.128 million in September to $0.32 million in October.
Total flexible ramping down uncertainty payment decreased from $18,984 in September to $4,330 in October.
Total forecast payment decreased from $0.122 million in September to $58,004 in October.
| Month | WEIM | FMM ELAP Prices | RTD ELAP Prices | Price Difference |
|---|---|---|---|---|
| 2025-10 | AVA | $34.07 | $36.41 | -$2.34 |
| 2025-10 | AVRN | $37.64 | $37.70 | -$0.06 |
| 2025-10 | AZPS | $26.01 | $28.68 | -$2.66 |
| 2025-10 | BANC | $43.15 | $43.61 | -$0.46 |
| 2025-10 | BCHA | $35.65 | $35.51 | $0.15 |
| 2025-10 | BPAT | $40.82 | $42.78 | -$1.96 |
| 2025-10 | EPE | $25.88 | $27.03 | -$1.14 |
| 2025-10 | IPCO | $33.20 | $34.83 | -$1.64 |
| 2025-10 | LADWP | $33.82 | $34.01 | -$0.19 |
| 2025-10 | NEVP | $28.23 | $30.04 | -$1.81 |
| 2025-10 | NWMT | $31.99 | $33.49 | -$1.50 |
| 2025-10 | PACE | $26.02 | $27.34 | -$1.32 |
| 2025-10 | PACW | $36.68 | $37.07 | -$0.39 |
| 2025-10 | PGE | $36.54 | $36.61 | -$0.06 |
| 2025-10 | PNM | $25.25 | $28.12 | -$2.87 |
| 2025-10 | PSEI | $36.27 | $35.97 | $0.30 |
| 2025-10 | SCL | $36.07 | $35.78 | $0.29 |
| 2025-10 | SRP | $26.25 | $27.76 | -$1.51 |
| 2025-10 | TEPC | $26.61 | $28.45 | -$1.85 |
| 2025-10 | TIDC | $45.87 | $46.16 | -$0.28 |
| 2025-10 | TPWR | $36.23 | $36.07 | $0.16 |
| 2025-10 | WALC | $28.07 | $28.91 | -$0.84 |