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 increased slightly in August compared to the previous month possibly due to higher temperature.
Across the integrated forward market (IFM), fifteen-minute market (FMM) and real-time dispatch market (RTD), default load aggregation point (DLAP) prices on average increased compared to the previous month, correlated with an increase in load.
The cumulative total congestion rent for interties increased from $1.63 million in July to $2.35 in August. Majority of the congestion rents in August accrued on NOB_ITC(17.4%) and MALIN500_ISL(82.3%). The congestion rent on MALIN500_ISL inter-tie increased from $130,445 in July to $1.94 million, while corresponding value of NOB_ITC decreased from $1,481,523 in the July to $408,938 in August.
In the congestion revenue rights (CRR) market, the balancing account had a surplus of approximately $9.99 million compared to $12.16 million in the previous month, which was allocated to measured demand.
In August the monthly IFM average procurement increased for non-spinning and regulation up, while decreased for regulation down and spinning reserves compared to the previous month. The monthly IFM average prices decreased for regulation down and increased for non-spinning reserves, regulation up, spinning reserves compared to the previous month.
The total bid cost recovery increased from $8.95 million in July to $14.3 million in August. Out of the total monthly bid cost recovery payment for the three markets in August, the IFM market contributed 13.2 percent, RUC contributed 57.8 percent, and RTM contributed 29 percent of the total bid cost recovery payment.
RTIEO increased from -$3.19 million in July to -$0.637 million in August. RTCO increased from $23.2 million in July to $31 million in August.
The monthly uplift payments increased from -$31,099 in July to $59,487 in August. Uplift payments was mainly caused by large exceptional dispatch value in August 17th.
The number of market disruptions increased from 13 in July to 24 in August. On August 20th, there were 9 (6 RTD, 2 FMM and 1 HASP) disruptions due to implementation of a market software patch. On August 7, there were 4 (4 RTD) interval disruptions due to implementation of a market software patch.
The total volume of exceptional dispatch increased from 34,661 MWh in July to 59,078 MWh in August. There was a spike on August 12, 13 and 14 due to the planned transmission outage.
The curtailment of renewable energy decreased in August compared to the previous month. Most curtailments continued to be solar.
Western Energy Imbalance Market (WEIM) performance:
The FMM ELAP prices in August increased for most entities, except BCHA, PSEI, SCL and TPWR, and were similarly volatile compared to the previous month. The RTD ELAP prices in August increased for all entities, except for BCHA, BPAT, PSEI and SCL, and 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 0.0733 percent in July to 0.116 in August. The cumulative frequency of negative FMM ELAP prices increased from 0.316 percent in July to 0.345 percent in August. The cumulative frequency of RTD ELAP prices above $250/MWh increased from 0.0555 percent in July to 0.158 percent in August. The cumulative frequency of RTD ELAP negative prices increased from 0.322 percent in July to 0.347 percent in August.
Total WEIM RTIEO decreased from -$0.25 million in July to -$1.08 million in August. Total WEIM RTCO increased from -$3.93 million in July to -$2.02 million in August.
Total WEIM BCR increased from $1.23 million in July to $1.57 million in August.
Total flexible ramping up uncertainty payment decreased from $0.207 million in July to $0.179 million in August.
Total flexible ramping down uncertainty payment increased from $3513 in July to $16,422 in August.
Total forecast payment decreased from $0.2 million in July to $0.177 million in August.
| Month | WEIM | FMM ELAP Prices | RTD ELAP Prices | Price Difference |
|---|---|---|---|---|
| 2025-08 | AVA | $33.16 | $34.46 | -$1.29 |
| 2025-08 | AVRN | $34.39 | $35.45 | -$1.06 |
| 2025-08 | AZPS | $32.54 | $36.57 | -$4.02 |
| 2025-08 | BANC | $42.92 | $42.62 | $0.30 |
| 2025-08 | BCHA | $33.45 | $33.44 | $0.01 |
| 2025-08 | BPAT | $35.79 | $35.88 | -$0.09 |
| 2025-08 | EPE | $33.10 | $39.02 | -$5.92 |
| 2025-08 | IPCO | $33.54 | $35.16 | -$1.63 |
| 2025-08 | LADWP | $43.43 | $44.79 | -$1.36 |
| 2025-08 | NEVP | $33.26 | $35.34 | -$2.07 |
| 2025-08 | NWMT | $33.22 | $34.62 | -$1.40 |
| 2025-08 | PACE | $33.72 | $35.54 | -$1.83 |
| 2025-08 | PACW | $33.23 | $34.31 | -$1.08 |
| 2025-08 | PGE | $33.70 | $34.32 | -$0.62 |
| 2025-08 | PNM | $39.64 | $42.76 | -$3.13 |
| 2025-08 | PSEI | $34.22 | $34.92 | -$0.70 |
| 2025-08 | SCL | $34.22 | $34.92 | -$0.70 |
| 2025-08 | SRP | $32.83 | $35.69 | -$2.86 |
| 2025-08 | TEPC | $31.92 | $34.77 | -$2.85 |
| 2025-08 | TIDC | $44.12 | $43.69 | $0.43 |
| 2025-08 | TPWR | $34.18 | $34.89 | -$0.71 |
| 2025-08 | WALC | $32.66 | $36.20 | -$3.54 |