The US Energy Information Administration, or EIA, publishes short notes called Today in Energy. On October 15, 2026, one of them reported that three regional transmission organizations set records for peak hourly load in the summer just past. They are PJM, the Electric Reliability Council of Texas (ERCOT) and the Southwest Power Pool (SWPP).
The figures come from Form EIA-930. Each balancing authority reports to EIA on that form. EIA shows them in its Hourly Electric Grid Monitor. Parts of the note follow, not the whole.
Three Records
PJM peaked at 162.6 GW on July 2, 2026, the note says. Its peak before 2026 was 160.6 GW, on June 23, 2025.
ERCOT peaked at 91.1 GW on July 22, 2026. Its record before 2026 was 85.5 GW, on August 20, 2024.
SWPP peaked at 58.0 GW on July 27, 2026. Its peak before 2026 was 56.0 GW, on August 21, 2023.
Each is the highest load in a single hour. EIA says most of these peaks came during regional heat waves, amid the hottest summer on record nationally, which drove up cooling demand.
The note puts most of these peaks down to heat. It does not split the load by who used it, so it cannot say how much of the peak came from new large users.
Close to the Line Elsewhere
Other grid operators came near their records. The California Independent System Operator and ISO New England came within 2% of theirs, the note says. The New York Independent System Operator was within 3%, and the Midcontinent Independent System Operator, MISO, within 4%.
MISO peaked at 121.5 GW on June 30, 2026. EIA says that is the highest in its Hourly Electric Grid Monitor, but below the peak of 127.1 GW on July 20, 2011, as MISO reported it. The New York Independent System Operator, too, reports a record set in 2013, before EIA collected hourly data.
What the Numbers Are
Each balancing authority reports to Form EIA-930, the note says, and EIA makes the data available as-is. The values represent the best at the time of reporting. Various reporting issues may limit their quality. And data the balancing authorities publish themselves may differ from the data in the form.
For anyone counting on spare capacity in these regions, the hour that matters is the peak, and in three of them it set a record this year.
Sources
- U.S. Energy Information Administration (EIA). PJM, ERCOT, and SWPP all set peak load records this summer (Today in Energy, in-brief analysis). 15 October 2026. energy agency