Almost 460,000 customers lack electricity in Southern US in ice storm's wake

Almost 460,000 electricity customers remained without service the afternoon of Feb. 2 across four US South-Central states in the wake of a brutal ice storm that knocked out service to more than 500,000 that morning, which lightened loads and weakened power prices in the region.

Electric Reliability Council of Texas North Hub real-time on-peak power was just $25.64/MWh around 1 pm on Feb. 2, down sharply from Feb. 1's average of $43.08/MWh, as outages weakened power demand. Similarly, the Midcontinent Independent System Operator's Arkansas Hub real-time price was just $24.73/MWh around 1 pm on Feb. 2, down from the Feb. 1 average of $37.87/MWh.

However, utilities made significant progress in restoring service as precipitation dissipated and temperatures rose above freezing in several areas.

Outages were almost exclusively caused by icy precipitation downing power lines, unlike the deadly mid-February 2021 winter storm which left about 4 million Texas power customers without service, some for days, which was primarily a problem with a lack of power supply.

Throughout the storm, ERCOT operations have remained in normal condition with, for example, an extra 7.9 GW of reserve supply available around 3:15 pm CT on Feb. 2, compared with current demand of about 56.7 GW and committed capacity approaching 73 GW.

MISO has also issued no supply related advisories and had terminated its severe weather alert as of 3 pm CT Feb. 2.

Texas hardest hit

Texas was hardest hit, with more than 440,000 without service the morning of Feb. 2, according to PowerOutage.us, but that number had diminished to about 347,000 as of 3 pm CT.

The capital city of Austin's municipal utility had the most customers without service – 152,340 as of about 3 pm CT according to the utility's outage web page, but Austin Energy warned on Aug. 1 that customers may have to go without service for 12 to 24 hours, as "challenging conditions may slow down" restoration efforts.

Oncor Electric Delivery, Texas' largest transmission and distribution utility, had the second-largest total, almost 143,000 as of 3 pm CT.

"Oncor and mutual assistance personnel continue to work night and day to restore power outages caused by the winter storm," the investor-owned utility said in a Feb. 2 news release. "Overnight bands of freezing rain have led to ice accumulations as high as a quarter of an inch in the Dallas-Fort Worth metro area, which has increased local outages. Communities in Oncor's eastern, northeastern and southern regions ... continue to experience the greatest impacts, with ice accumulations reaching half an inch. Ice can increase the weight of tree branches up to 30 times, leading to sagging or broken branches impacting lines, and add hundreds of pounds of extra weight to power lines."

Ice, winter advisories ended

The National Weather Service's ice and winter weather advisories had been deleted by 3:30 pm CT Feb. 2. CustomWeather forecast ERCOT's population-weighted average low temperature on Feb. 3, at 41 degrees F, to exceed the normal level of 39.2 F for the first time since the storm hit.

However, as temperatures climb and ice falls off tree limbs, these limbs may "suddenly spring up into lines, causing additional outage impacts," Oncor said.

ERCOT forecast its peakload to plunge from about 62.3 GW Feb. 2 to 53.7 GW on Feb. 3, but ERCOT North Hub day-ahead on-peak power trading for Feb. 3 indicated higher prices, around $32.25, compared with Feb. 2's real-time prices in the mid-$20s/MWh , as normal business routines were expected to resume without heavy power demand for heating.

The MISO South region's load on Feb. 2 was forecast to peak at 21.7 GW, down about 1.7 GW or 7.1% from Feb. 1's peak of 23.4 GW, but loads were forecast to rise to 23.3 GW on Feb. 2. MISO South includes vertically integrated utilities in Arkansas, Louisiana, Mississippi and Texas, and outside of Texas, Arkansas was hardest hit by the ice storm.

The MISO Arkansas Hub had some slight strengthening of prices Feb. 2, as MISO's day-ahead price of $25.55/MWh for Feb. 3 delivery was in the range of Feb. 2's real-time prices and that of the previous five-year average for that date.