North Texas here, green energy had very little to do w/ this, it was simple supply and demand.
The Texas grid is designed for peak usage in July/Aug/Sept, so when its gets to be 110 degrees outside the power plants which are primarily gas powered have all the natural gas they need t to generate MW of energy, I mean I'm not running my gas furnace when its 110 outside.
So come Sunday the temps are dropping into the single digits, I;ve lived in Dallas for 30+ years and I don;t recall ever seeing single digits, so those gas powered power plants start cranking MWs and at the same time at my house, the gas furnace is running none stop (BTW folks forget most home HVAC systems are designed for a 30 degree delta, ie if its 10 degrees out, you should expect the inside temp to be 40, yea, my furnace is going to run non-stop), so I;m sucking down as much natural gas as I can get.
See the problem? the grid was not designed to have consumers sucking down gas at the same time as the power plants. So the power plants that were operating could not maintain line pressure because there was not enough gas in the system. Add to the fact the pipelines were not engineered for extreme cold it all cascaded down. The -2 Tuesday morning was the coldest in 120 years, 120 years ! normally in mid-Feb in Dallas its 60 during the day and 40 at night.
The windmills are a strawman for the real cause, ERCOTs winter plan calls for like 5% wind power, wind is just not the winter plan, last time I checked you need temp differential to create wind and we don't have much wind in the winter here, spring is a different story. ERCOT's plan forecasted a max low of 10 degrees, and they had NO plan if it dropped below that.
It went from potential blackouts at like 11pm Sunday, to rolling blackouts at 2am Monday, so we had a 3 hour warning in the middle of damn night to prepare. Since this deep freeze had been forecasted for a good week and once the weathermen on TV got it right, almost to a T on the temps and snowfall, Governor Abbot or someone should have gone on TV on Saturday and said "hey its gonna get very very cold next week and you should prepare for extend periods of time w/o power, just like South Texas does during hurricane season," Would that have made a difference I don;t know and we will never know because no one and I mean no one in Gov't mentioned blackouts until they happened. But windmills were not the problem. The problem is lax planning and failure of state gov;t and a junior senator to accept responsibility.