How the Lights Stay On

Chapter 8: The Frozen Texan

Sometimes a disaster is in the forecast for days, and you can watch it coming.

In the first week of February 2021, meteorologists across North America began to notice something unusual happening in the upper atmosphere. The polar vortex — a swirl of frigid air that normally stays trapped around the Arctic — was wobbling. Pieces of it were breaking off and sliding south. By the second week of February, one of these pieces was heading directly into the central United States.

The weather service issued warnings. The temperature in Dallas would drop below zero for the first time in decades. In some parts of Texas, the temperature would fall by more than fifty degrees in twenty-four hours. The storm, eventually called Winter Storm Uri, would freeze a region that had not been seriously frozen since the 1950s.

People stocked groceries. People filled bathtubs with water in case the pipes froze. Schools and businesses closed. The state braced itself.

Then the storm arrived, and the grid started to fail.

By the time Texas thawed out a week later, somewhere between 246 and 700 people would be dead. It would be the worst weather disaster in Texas history. And almost none of those deaths were directly caused by the cold itself. They were caused by the failure of the grid.

Texas, you may remember from Chapter 2, has its own electrical grid.

When the great American grids were being interconnected in the twentieth century, most states gradually joined either the Eastern Interconnection or the Western Interconnection — the two giant synchronized machines that span the rest of North America. Texas chose differently. The Texas grid, run by an organization called ERCOT (the Electric Reliability Council of Texas), kept itself almost entirely separate from the others.

There was a reason for this. By staying separate, Texas’s grid was not subject to federal regulation in the way that interstate grids are. The Federal Energy Regulatory Commission, or FERC, can set reliability rules for the Eastern and Western grids because they cross state lines. ERCOT crosses no state lines, and so has historically operated under Texas state rules instead — which were lighter and friendlier to producers.

This choice had real advantages. Texas built electricity infrastructure faster than almost any other state. Wholesale electricity prices were often lower than in California or the Northeast. Texas became, eventually, the largest wind-power producer in the country and one of the largest solar producers, partly because the regulatory environment made it easy for new generators to enter the market.

It also had a quieter cost, which would become very loud in February 2021.

After a smaller freeze in 2011 had caused brief blackouts, Texas’s regulators had recommended that generators winterize their equipment — wrap pipes, install heaters on critical components, protect against extreme cold. The recommendation was voluntary. Most generators did not do it, because doing it would have cost money, and the market did not reward them for being reliable in extreme weather. They were paid for electricity they actually delivered. If they were offline during a freeze, they simply did not collect that revenue. The math, for the generator, was to skip winterization and accept the occasional bad week.

The math, for the people of Texas, would turn out very differently.

The freeze began on Sunday, February 14, 2021 — Valentine’s Day.

By Monday morning, demand on the Texas grid was setting all-time winter records. Millions of homes had electric heating systems — including many cheap electric resistance heaters that are extremely inefficient. People who normally used natural gas to heat their homes also needed electricity for blowers and pumps. Even gas customers were drawing more electricity than usual.

And at the same moment that demand was climbing, supply was falling apart.

Natural gas, which provided more than half of Texas’s electricity, was failing in two ways. The wellheads in west Texas were freezing — water in the gas itself was forming ice plugs in the pipes. And the pipelines and compressor stations that moved the gas to power plants were freezing too. Some compressor stations had electric components that themselves needed electricity to run, which meant that as the grid lost generation, the gas system also lost ability to deliver fuel to the plants that still worked. It was a feedback loop in the worst possible direction.

Coal plants were failing as well — frozen pulverizers, frozen conveyor belts, frozen coal piles. A nuclear reactor at the South Texas Project tripped offline because a water-level sensor froze (an embarrassingly small failure, given the size of the plant). Wind turbines, which had not been winterized for the Texas climate, iced over and stopped turning. Some solar panels were covered in snow.

By Monday morning, February 15, ERCOT’s control room was watching its supply collapse minute by minute. The grid’s frequency began to drop below 60 hertz — the heartbeat we met in Chapter 2. Then below 59.9. Then below 59.8.

If frequency stays below 59.4 hertz for more than nine minutes, automatic equipment begins disconnecting generators from the grid to protect them from physical damage. Once that starts, it cannot be easily stopped. The grid would collapse entirely.

At 1:51 AM on Monday morning, ERCOT made the only decision left: they began ordering utilities to cut power to their customers. The plan was to rotate the blackouts — to leave each neighborhood dark for thirty or forty-five minutes at a time, then move on. This was supposed to bring demand down to a level the surviving supply could meet.

The plan did not work as intended.

The problem with rolling blackouts is that they are surprisingly hard to actually roll.

The grid is not divided into neat blocks the size of city neighborhoods. It is divided into circuits that follow the historical accidents of how transmission lines were built, which substations serve which areas, which lines were upgraded in which decades. Some circuits cannot be disconnected without taking down a hospital, a fire station, a water treatment plant, a natural gas compressor station. Those circuits are protected — they have to stay on.

Once the protected circuits in each neighborhood are accounted for, what is left is often a much smaller set of circuits that can actually be turned off. And so the burden of rotating blackouts falls disproportionately on those circuits — and on the people who happen to live on them.

In Texas, during the freeze, some neighborhoods stayed dark for fifteen minutes. Other neighborhoods, just a few blocks away, stayed dark for four days.

For people who lost power in subzero temperatures, the first few hours were uncomfortable. The next few hours were dangerous. By the second day, in homes that were not built to retain heat, the indoor temperature was approaching the outdoor temperature. Pipes were freezing and bursting, flooding kitchens with ice water. People wore every layer of clothing they owned and huddled in bathrooms with the doors closed.

Some people, desperate for warmth, brought charcoal grills inside. Charcoal produces carbon monoxide, which is colorless and odorless and lethal. Multiple families died this way, parents and children together in their living rooms.

Others ran cars in attached garages to warm up. Carbon monoxide killed them too.

Others left their homes to sit in their running cars in the driveway, just to charge their phones. Some of those people, exhausted from cold and sleeplessness, fell asleep with the engine running. They did not wake up.

In a Houston-area suburb, an eleven-year-old boy died in his bed of hypothermia during the night. His mother had been keeping him as warm as she could. The house had been without power for nearly two days.

He was not alone. Across Texas, that week, somewhere between 246 and 700 people died from causes directly traceable to the grid failure. The lower figure is the official state count. The higher figure comes from analyzing excess mortality — comparing how many people actually died that week to how many would normally have died in a typical February week — and is what most independent researchers believe is closer to the truth.

After the disaster, ERCOT’s CEO told a state legislative hearing that the Texas grid had come within four minutes and thirty-seven seconds of complete catastrophic failure.

If ERCOT’s frantic measures had not worked — if they had not been able to shed enough load by cutting power to millions of homes — the grid’s frequency would have fallen below the safety threshold, and the entire Texas Interconnection would have collapsed.

What does “complete collapse” mean? It means every generator disconnecting from the grid simultaneously. It means a state of thirty million people suddenly with zero electricity, including the equipment used to start power plants. Restarting a grid from a complete collapse is called a black start, and it is one of the most difficult operations in all of electrical engineering. It requires bringing generators online one by one, using small backup generators (themselves cold and possibly frozen) to power the equipment needed to start the bigger ones. Each generator, once started, has to be carefully synchronized to the small piece of grid being slowly rebuilt.

If the Texas grid had fully collapsed in February 2021, experts at the time estimated it could have taken weeks to months to restore power across the state. In subzero temperatures. With pipes already freezing. With food rotting in dark refrigerators.

That is what four minutes meant.

In the months after the freeze, Texas politicians held hearings. ERCOT’s CEO was fired. Several of the state’s Public Utility Commissioners were forced to resign. Investigations were launched.

In 2021 and 2022, the Texas legislature passed laws requiring power plants and natural gas facilities to winterize their equipment. The Public Utility Commission established new rules. ERCOT changed how it operated.

When the next major winter storm hit Texas in December 2022, the grid mostly held. There were some outages, but not a collapse. The winterization rules had partly worked.

But several things did not change.

Texas remained part of its own interconnection, separate from the rest of the United States. Proposals to build major transmission ties with the Eastern Interconnection — which would have allowed Texas to import electricity from other states during emergencies — were not adopted. The decision to stay independent of federal regulation was reaffirmed politically.

The regulatory structure remained largely market-based. Generators are still rewarded primarily for electricity they actually deliver, not for being reliable through extreme weather, though some adjustments have been made.

And the deepest structural choice — whether Texas would be a state that prizes cheap, abundant electricity above almost everything else, or one that prizes resilience and consumer protection — remained, fundamentally, the choice it has always been.

It is tempting, especially for people who do not live in Texas, to tell a simple story about the freeze: a state with too much faith in markets and too little willingness to be regulated finally paid the price. Texans got what they bargained for.

This story is partly true. It is also too simple, and it is not fair.

Texas’s regulatory choices have produced real benefits for many decades. Cheap electricity. Easy entry for new generators. The fastest wind-power buildout in the country. Texas now produces more wind energy than any other state — more than several whole countries — partly because the same light regulatory hand that left the grid vulnerable in February 2021 also let wind farms get permitted and connected in months rather than years. The same trade-off cuts in both directions.

Texas’s voters and politicians have consistently chosen this trade-off. They have done so with information from earlier freezes and earlier warnings. They could have chosen differently. They have chosen, repeatedly, not to.

This is the deeper truth that Winter Storm Uri laid bare. The Texas freeze was not really a story about an engineering failure. It was a story about a political choice, made over many decades, that produced an engineering outcome.

This is true everywhere. California’s blackouts during wildfire season are a story about the choice to live in fire-prone areas while running aging electrical infrastructure. Germany’s energy crisis after the 2022 invasion of Ukraine was a story about the choice, made decades earlier, to depend on Russian gas while shutting down nuclear plants. France’s relatively stable electricity prices through that same crisis were a story about the choice, also made decades earlier, to build a fleet of nuclear reactors.

There is no grid anywhere in the world whose performance is separable from political and economic choices. The reliability you experience is not just an engineering outcome. It is a political outcome that happens to be engineered.

Several months after the freeze, on a sweltering August evening, the same Texas grid was operating at near-record demand. Air conditioners were running across the state. ERCOT was managing the load minute by minute. The frequency stayed near 60 hertz. The lights stayed on.

Somewhere in a Houston suburb, a family was eating dinner together. The mother had lost a son in February. The grid that had failed her in winter was, that summer, working perfectly. The same engineers, the same control room, the same set of choices.

She set the air conditioning a degree cooler. She watched her remaining children at the table. The lights did not flicker.

The grid is a machine. The grid is also a mirror. It shows you, over time, the priorities of the people who built it.

In February 2021, the Texas grid showed something that people in Texas — and people watching from elsewhere — did not love seeing. But it was true. It is still true.

And the only way that picture changes is by changing the choices underneath it. Slowly. Imperfectly. By voters and engineers and legislators and ordinary people, deciding what they are willing to pay for what they want to get.

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