Three U.S. regional transmission organizations set records for peak hourly electricity load this summer, according to the U.S. Energy Information Administration. PJM reached 162.6 gigawatts (GW), the Electric Reliability Council of Texas (ERCOT) reached 91.1 GW, and the Southwest Power Pool (SWPP) reached 58.0 GW. The figures come from Form EIA-930 data shown in EIA's Hourly Electric Grid Monitor.
Most of the peaks came during regional heat waves in the hottest summer on record nationally, which pushed up cooling demand.
Records set in 2026
| Operator | 2026 peak | Date | Prior record | Increase |
|---|---|---|---|---|
| PJM | 162.6 GW | July 2 | 160.6 GW (June 23, 2025) | 1.3% |
| ERCOT | 91.1 GW | July 22 | 85.5 GW (August 20, 2024) | 6.5% |
| SWPP | 58.0 GW | July 27 | 56.0 GW (August 21, 2023) | 3.5% |
ERCOT posted the largest jump over its old mark, at 6.5%.
Four operators came close
The California Independent System Operator (CAISO) and ISO New England (ISO-NE) finished within 2% of their previous records. The New York Independent System Operator (NYISO) came within 3%, and the Midcontinent Independent System Operator (MISO) within 4%.
CAISO reached 50.0 GW on September 9, 2026, against its record of 51.1 GW on September 6, 2022. ISO-NE hit 25.3 GW on July 2, 2026, short of its 25.9 GW record from June 24, 2025. NYISO reached 31.1 GW on July 2, 2026, below its 31.9 GW peak of June 24, 2025. NYISO itself reports a 34.0 GW record set in 2013, before EIA collected hourly data.
MISO peaked at 121.5 GW on June 30, 2026. That is the highest in EIA's Hourly Electric Grid Monitor, but below the 127.1 GW peak of July 20, 2011, as reported by MISO.
Data caveat
Each balancing authority reports its Form EIA-930 data to EIA, and the data are made available as-is. EIA notes that reporting issues may limit quality, and that figures published directly by balancing authorities may differ from the Form EIA-930 numbers.
