Texas heat brings the state's power grid closest it has been to outages since 2021 winter storm

abcnews.go.com:

The sweltering heat wave in Texas has the power grid manager again asking residents to cut electricity use

HOUSTON — Texas’ power grid manager on Thursday again asked residents to cut their electricity use as the state endures another stretch of sizzling summer heat. The request carried fresh urgency, coming the day after the system was pushed to the brink of outages for the first time since a deadly winter blackout in 2021.

The request by the Electric Reliability Council of Texas, which serves most of the state’s 30 million residents, came a day after low energy reserves prompted the grid operator to issue a level 2 energy emergency alert. Operating reserves fell as demand surged amid the heat, and power from wind and solar energy sources proved insufficient, according to ERCOT.

It was the first time the council entered emergency operations since a deadly 2021 ice storm knocked out power to millions of customers for days and resulted in hundreds of deaths.

The emergency status remained in place for about an hour Wednesday night until grid conditions returned to normal, ERCOT said in a post on X, formerly known as Twitter.

Besides low reserves, ERCOT said it issued Wednesday's emergency alert because of a “drop in frequency,” which refers to the generation of electrical power. A spokesperson for ERCOT did not immediately return an email seeking comment on what caused the drop in frequency.

But Thomas Overbye, a professor of electrical and computer engineering at Texas A&M University, said such a frequency drop is usually caused by a large power plant going offline, which could have a significant impact.

“These generators have been running, you know, a lot all summer. So that means that maintenance that we might want to