Texas has invested more in wind and solar power than any other state in recent years, but during the current cold snap, natural gas has played a key role in keeping the lights on.

During the past few days, renewable energy was a small but meaningful part of the energy mix that delivered electricity to Texans. But starting on Sunday, as wind chills dipped below 0 degrees Fahrenheit in some Texas cities and demand surged, especially in morning hours when residents awakened, the grid leaned heavily on gas, according to data from the Electric Reliability Council of Texas, the grid operator.

As the mercury has dropped, many Texans have been thinking about the winter storm of 2021, when power failures were blamed for some 240 deaths. Disinformation spread back then, wrongly blaming wind energy. While some wind turbines froze in 2021 and coal plants were knocked offline, it was frozen natural gas plants that were the main problem. Power was out for days in some areas.

Since then, state officials have weatherized pipes and gas equipment and also shored up wind turbines and other equipment. Grid operators have also issued calls for conservation during those crucial morning hours. All of that led them to project confidence that the grid would hold up this week.