U.S. electric grid operators and utilities from the Plains to Pacific Ocean are bracing for record temperatures and spiking power demand amid a regionwide heat wave forecast to create tight capacity conditions through June 18.
The Electric Reliability Council Of Texas Inc. on June 14 issued a call for conservation for the next five days, citing a "significant number of forced outages" among power plants. High temperatures in major cities such as Austin, Dallas and Houston are expected in the mid to upper 90s, according to the National Weather Service.
The grid operator, known as ERCOT, saw peak demand in the afternoon of June 14 exceed 70,000 MW, beating a prior peak demand record for June of 69,123 MW, set in 2018, according to the grid operator. At the same time that high demand was expected, power plant operators had 12,178 MW out of service for repairs as of 2:30 p.m. CT, contributing to an unanticipated capacity crunch, ERCOT spokesperson Leslie Sopko said during a media briefing.
Of that amount, 9,066 MW was thermal generation and the rest was renewable energy. Typically, thermal generators have only about 3,600 MW of capacity offline for repairs on hot summer days, ERCOT said. Peak wind generation was also expected to be approximately 1,500 MW below normal levels.
Day-ahead on-peak power prices on June 14 were in the low $80s/MWh in ERCOT's four zones, according to S&P Global Market Intelligence data, more than double prices on June 11.
"We will be conducting a thorough analysis with generation owners to determine why so many units are out of service," ERCOT Vice President of Grid Planning and Operations Woody Rickerson said in a statement. "This is unusual for this early in the summer season."
ERCOT asked Texans to reduce air conditioning use, turn off lights and pool pumps and avoid using large appliances, among other conservation measures.
ERCOT outages 'very concerning'
This latest test for the embattled Texas grid operator comes after ERCOT suffered a near-total collapse of its transmission system during a winter storm in February, forcing a large-scale multiday load shed that left millions of residents without power. ERCOT also had a near-miss situation in April, when it was forced to call for conservation as a quarter of its fleet was down for repairs.
Different than in April, however, when large-scale generator outages are not unusual to conduct repairs and prepare for summer, the vast majority of outages on June 14 were unanticipated, according to Warren Lasher, senior director of system planning at ERCOT.
A recent summer reliability assessment that forecast record demand did not foresee such high levels of generator outages.
"I find the current number of units on outage to be very concerning," Lasher said during the media briefing. The executive declined to name the number or type of thermal generators out of service but said they were spread across the ERCOT service territory.
Lasher also declined to speculate on whether a revision of the state's scarcity pricing rule — criticized for hitting retail energy providers and other market participants with $9,000/MWh prices during the February crisis — was inadvertently causing generators to misinterpret the need to be online.
Calif. rotating outages 'could become necessary'
Across the West, dozens and possibly hundreds of daily record high temperatures "are likely to be set over the next few days in California, Intermountain West, Desert Southwest, Rockies, and High Plains," the National Weather Service said in a June 14 forecast. Sacramento, Calif., for example, is expecting a high temperature of 110 degrees on June 17, and Phoenix is expecting high temperatures above 115 degrees every day through June 19.
Gusty winds and high heat are also creating conditions for fire weather across large swaths of the region.
The California ISO said it may also call for conservation but had not yet done so as of midday on June 14. The state's primary transmission grid operator has placed restrictions on maintenance between June 15 and June 18.
The grid operator is not expecting the need for rotating blackouts.
"But as happened during an intense regional heat wave last August that hit much of the Western U.S., rotating power outages could become necessary if weather and stressed grid conditions persist or worsen," CAISO said in a June 11 statement.
The anticipated increases in electricity demand were also driving wholesale power prices higher. Day-ahead on-peak prices at CAISO's two hubs on June 14 and two main desert Southwest trading hubs were all about four times higher than on June 11, according to Market Intelligence data.
