The declaration of a so-called Level 2 emergency late on Wednesday came in response to shrinking supplies of available power and meant the Electric Reliability Council of Texas, the state’s grid operator, had to draw on reserves while pushing consumers to curb usage.

ERCOT called off all emergency warnings as of 9pm local time.

Texas hadn’t experienced a grid emergency since February 2021, when a historic freeze triggered blackouts that led to hundreds of deaths, stranded millions inside freezing homes, and paralysed the Lone Star State for almost a week.

Conditions deteriorated so quickly on Wednesday that the grid operator skipped calling emergency level 1. A level 2 emergency means power reserves have dropped to critical levels and allows the operator to call on more supplies to prop up the grid. It’s unclear what led to ERCOT calling a second-tier emergency. 

Read More: Texas Falls Short of Big Grid Overhaul After Deadly Winter Storm

As the crisis deepened late on Wednesday, utilities in San Antonio and the state capital Austin warned blackouts might be imminent and urged customers to take conservation efforts such as not charging electric cars and turning off pool filters. Medically fragile residents who need oxygen and similar aids were urged to have backup plans in place.

Spot power prices surged to more than $5,000 a megawatt-hour, exceeding the price cap, multiple times on Wednesday evening. That was quadruple the cost of power supplies for that period in the day-ahead market.

“We knew wind was low and demand was high, but there was no reason to expect conditions to be worse than many other days this summer,” said Katie Coleman, an attorney for the Texas Industrial Energy Consumers. “We are still trying to understand what happened.”

ERCOT’s move comes after the state’s GOP leadership lauded what it said were comprehensive grid overhauls that would prevent a repeat of the 2021 winter blackout. ERCOT didn’t immediately respond to a request for comment.

The alert was called during the evening, the time of day that now has become perilous for grid operators because supplies of solar power go down but other generation sources aren’t always available to pick up the slack. DM