We have some answers along with more questions about those rolling blackouts that have now ended.
Texas set a new winter record for electricity usage Wednesday night: 56,334 megawatts. That's enough to power more than 11 million homes in frigid weather.
With adequate power now flowing again to meet winter demand, the questions are flowing about what led to the rolling blackouts.
The Electric Reliability Council of Texas, the agency that manages the grid, is supposed to alert power delivery companies like Oncor, the state, local governments and the public that blackouts are coming.
That did not happen on Wednesday.
"It's unfortunate that these events unfolded quickly, and often that presents a challenge in communication," explained ERCOT CEO and president Trip Doggett at a Thursday news conference.
ERCOT said it took action when it learned the cold knocked out more than 50 generating units.
But WFAA's sister station KHOU reports that late on Tuesday night, ERCOT told the Public Utility Commission of "minor concerns" of higher demand.
But then — about four hours later — it sent an alert that reserves were dropping.
After 6 a.m. Wednesday, ERCOT told the PUC the rolling blackouts were under way.
"It appears as if things may have happened so quickly that one or two of those communication steps did not occur," said PUC Chairman Barry Smitherman.
PUC Commissioner Ken Anderson wants to know if power generating companies — like Dallas-based Luminant, the state's biggest power company — prepared their plants.