By one measure, the Texas electric power grid weathered a late December cold snap, one of the first winter storms since the disastrous February 2021 event known as Uri.

Uri resulted in widespread power outages as multiple fossil and renewable energy facilities either froze or were offline due to fuel supply issues. By some counts, hundreds died as a result of the power outages.

In comparison, December 2022 was no comparison: no widespread outages and few, if any, issues with generating units.

But a closer look by local news outlet Texas Monthly suggests that at least one issue remained troubling: natural gas supplies.

The news organization said that Texas had trouble delivering natural gas during the cold weather event. It said that over a five-day period in February 2021, the state’s gas processing capacity fell by 84%, keeping large amounts of gas out of the state’s network of pipelines. 

By contrast, over a two-day period in December, the state’s gas processing capacity fell by 34%, the news outlet said, quoting data from Wood Mackenzie.

On the residential side of things, Atmos Energy, which supplies gas to homes across the state, came up short as it worked to deliver gas to customers in suburban Dallas and Austin. Governor Greg Abbott has asked for an investigation into what happened, Texas Monthly said.

It also reported that power plants had trouble getting gas to burn. It said that officials at grid operator Electric Reliability Council of Texas (ERCOT) ordered several electric power generators to burn fuel oil because those plants didn’t have enough natural gas. The fuel was available as a backup because of a reform put in place after the 2021 blackouts. ERCOT reportedly paid more than $50 million this winter for 19 power plants to have backup fuel on hand.

During the December cold snap, ERCOT asked the U.S. Department of Energy for permission to exceed normal federal air quality restrictions to allow generators to burn otherwise noncompliant fuel oil. The federal agency granted the ERCOT request.

And at least 2,100 MW of natural gas–fired electrical generation had to shut down at some point during the December 22–24 cold weather because of a lack of gas. ERCOT said in recent days it was investigating why so many plants tripped off-line.  

One complicating factor may have been unexpected electricity demand. On the morning of December 23, demand topped 74,000 MW. That surpassed an ERCOT forecast that demand during the cold weather event would peak at just under 70,000 MW.

And demand was well above a seasonal forecast that ERCOT issued just weeks earlier. That forecast pegged expected peak winter demand–based on average weather conditions–at about 67,400 MW.

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