HOUSTON, Texas: A powerful winter storm disrupted U.S. energy production and power systems over the weekend, knocking out as much as two million barrels per day of crude oil output and triggering sharp price swings across oil, gas, and electricity markets.

Oil production losses peaked on January 24 at around two million bpd, or roughly 15 percent of U.S. output, according to estimates from analysts and traders. Consultancy Energy Aspects said the Permian Basin bore the brunt of the outages, accounting for about 1.5 million bpd of the decline.

Shut-ins eased by January 26, with Permian production losses estimated at roughly 700,000 bpd, and output expected to be fully restored by Jan. 30, Energy Aspects said.

Several major producers reported weather-related disruptions. ConocoPhillips' Permian crude output was down by about 175,000 bpd as of January 25 due to frigid conditions, according to a source familiar with the matter. A company spokesperson said ConocoPhillips typically does not comment on day-to-day operations.

Chevron reported that hatches were frozen open during the storm in Midland, Texas, according to a regulatory filing. Chevron did not immediately respond to a request for comment.

At ExxonMobil, multiple gas compressor shutdowns across different fields affected oil production because gas compression is used to lift oil, a source said.

"We closely monitor severe weather conditions and proactively implement necessary safety and operational measures to safeguard our people, maintain infrastructure integrity, and ensure continuity of essential operations," an ExxonMobil spokesperson said.

Producers also faced third-party takeaway challenges due to hazardous road conditions, limiting water hauling and technician access for repairs, the Texas Oil and Gas Association said.

More than two dozen upsets were reported at natural gas processing plants and compressor stations in Texas, including facilities operated by Occidental and Targa Resources, according to regulatory filings. Analysts noted this was far fewer than the more than 200 upsets recorded during the first five days of the severe 2021 winter storm.

In North Dakota, the third-largest U.S. oil-producing state, output was estimated to be down by 80,000 to 110,000 bpd as of January 26 morning, Justin Kringstad, director of the North Dakota Pipeline Authority, said. Associated natural gas production was down by 0.24 to 0.33 billion cubic feet per day.

U.S. crude futures settled down 44 cents at US$60.63 a barrel. Average natural gas output in the Lower 48 states slipped to 106.9 bcfd in January from a record 109.7 bcfd in December, according to LSEG, as producers shut in supply.

On the refining side, freezing weather disrupted operations along the U.S. Gulf Coast. ExxonMobil shut units at its Baytown, Texas, petrochemical complex, while Cenovus Energy's 172,000 bpd Lima, Ohio, refinery experienced mechanical issues that could delay a complete restart until later this week, industry monitor IIR said.

Peak natural gas production losses could reach about 20 bcfd, according to Rystad Energy. Front-month gas futures jumped nearly 30 percent to settle at $6.80 per million British thermal units, their highest since December 2022.

About 810,000 customers across the U.S. remained without power on January 26 after snow, sleet, and freezing rain swept from the Gulf Coast to New England. PJM, the largest U.S. power grid, forecast generation outages of 22.4 gigawatts, or about 16 percent of committed capacity, though it continued to meet demand.

Wholesale power prices surged, with next-day prices in New England rising 82 percent to $313 per megawatt hour, while PJM West prices jumped about 360 percent to around $413, their highest since January 2014.