Texas Warns of Potential Blackouts on Extreme Heat and Low Wind

(Bloomberg) -- Texas officials are warning of possible rolling blackouts Thursday evening as a blistering heat wave bears down on the central US. 

The state has a “high potential” to declare an energy emergency, the Public Utility Commission warned, as unusually low winds cut into the available electricity supplies just as millions of air conditioners drive up demand.

That would mark the most serious threat to the Texas grid thus far this summer. The neighboring Midwest grid operator is also warning of short supplies. The vast expanse of the heat will limit the ability to import power from other grids, potentially exacerbating any shortages.

“It’s basically every grid for themselves at that point,” said Joshua Rhodes, an energy research scientist at the University of Texas at Austin.

The National Weather Service is warning that temperatures in Dallas may reach 108F (42C) and 104F in Topeka, Kansas. Heat alerts stretch across 20 states from Minnesota to Louisiana. 

This week’s heat wave is smashing records dating back more than a century, taxing energy grids and raising health risks in a region with a population of about 145 million. It’s the latest in a string of climate disasters, from deadly wildfires to hurricanes, that have pummeled the US in recent weeks. 

The Electric Reliability Council of Texas anticipates power supplies falling short of demand from about 7 p.m. to 9:30 p.m. local time, according to forecasts compiled by Nrgstream, a data provider. Grid operator Ercot serves 26 million customers in the state and is calling on the public to voluntarily reduce power consumption.

“What we are seeing is conditions that are more tight than we have seen at any other day this summer,” Ercot CEO Pablo Vegas told the state utility regulators Thursday morning. “At this time, it is a high likelihood that we expect to be in emergency operations this evening.”

Slack winds are contributing to power constraints. Wind was supplying about 5.8 gigawatts of capacity at 3 p.m., about 7.1% of the energy mix. That’s about 56% of the wind power usually available in the summer, and well down from the 14.1 gigawatts of wind power that was available at the same time Wednesday. 

Still, the constraints are likely to mean 15-minute rolling outages in residential neighborhoods, in contrast to the crippling blackouts that gripped Texas in 2021 during deadly Winter Storm Uri. 

The Midwest power grid is also facing surging demand as temperatures soar, with the Midcontinent Independent System Operator issuing a warning Thursday that it may run short of supplies. By afternoon it had walked back the notice, but the grid will remain tight. MISO serves 45 million customers in 15 states from North Dakota to Mississippi, as well as Canada’s Manitoba province.  

In the Midwest, “the record-breaking heat wave is driving electricity demand to near all-time highs,” Brandon Morris, a spokesman for MISO, said in an email. 

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