Multi-day power outages hit major Texas cities last week as unusually frigid temperatures exposed weaknesses in an electricity system designed for an earlier era. More than 3 million Texans lost lights, heat and food refrigeration in a series of "rolling blackouts" – a step taken avoid a total system collapse amid high demand after snow and ice storms. An underlying problem was the state's failure to winterize gas lines, oil pipes, wind turbines and other essential equipment with enough insulation and heaters. Texans rely on natural gas for two-thirds of their winter electricity supply, and failures across that delivery system were the biggest cause of outages. Instruments froze and low pressure in pipelines limited the flow of that fuel. "Maximizing profits means you don't fix stuff unless it's actually broken," says state Rep. Jon Rosenthal, a Democrat from Houston who wants lawmakers to "require companies to do things like winterize their stuff."

At the same time, an Austin ice storm knocked down power lines and short-circuited transformers. Another reason for the crisis was Texans' massive use of electric heaters all day and night, creating a demand normally seen only on the hottest days during summer air-conditioning season. State utilities reduce generating capacity during winter and take some power plants offline for maintenance. At Gov. Greg Abbott's request, President Biden authorized money and supplies for the state. The Federal Emergency Management Agency sent generators to state hospitals, water plants and other critical facilities, along with blankets, food and bottled water. It also delivered diesel fuel for backup power.

The Republican governor and executives in the coal and gas industries blamed the crisis on frozen wind turbines and solar plants, which account for about 13% of Texas' winter power. But the emergency in an energy-drilling state shows reflects a broader national concern about energy reliability in an era when weather extremes occur more often than in past decades. Utilities in California, Minnesota, Mississippi and elsewhere imposed temporary blackouts earlier for various reasons.

Professor says: "Every one of our sources of power supply underperformed. Every one of them is vulnerable to extreme weather and climate events in different ways. None of them were adequately weatherized." -- Daniel Cohan, associate professor of civil and environmental engineering at Rice University in Houston

State legislator says: "There are lot of folks culpable for this and there is going to be a reckoning of the policy decisions that have been made in the past." – Rep. Lyle Larson, a Republican whose district includes San Antonio

Journalist says: "America can put a man on the moon but Texas can't keep the lights on. Houston, we have a problem." – Dan Rather, former CBS News anchor, in tweet