Why the power grid failed in Texas and beyond – tech2.org

Why the power grid failed in Texas and beyond


DALLAS (AP) – The power outages plaguing Texas in unusually arctic temperatures are exposing weaknesses in an electrical system designed when seasonal changes in weather were more consistent and predictable – conditions that most experts believe no longer exist.

This is not just happening in Texas, of course. Utilities from Minnesota to Mississippi have imposed continuous blackouts to relieve stress on power grids that have buckled under high demand in recent days. And power outages have become a rite of summer and fall in California, in part to reduce the chances of deadly wildfires.

But the fact that more than 3 million frozen Texans have lost their electricity in a state that prides itself on its energy independence underscores the severity of a problem that is occurring in the United States with increasing frequency.

WHAT HAPPENED IN TEXAS?

Low temperatures caused Texans to turn on their heaters, including many inefficient electrical ones. Demand skyrocketed to levels normally seen only on the hottest days of summer, when millions of air conditioners are running at full throttle.

The state has a generating capacity of about 67,000 megawatts in the winter compared to a peak capacity of about 86,000 megawatts in the summer. The gap between winter and summer supply reflects that power plants are shut down for maintenance during months when demand is generally less intense and there is not as much energy coming from wind and solar sources.

But planning for this winter did not envision temperatures cold enough to freeze natural gas supply lines and stop wind turbines from spinning. As of Wednesday, 46,000 megawatts of power were off statewide – 28,000 from natural gas, coal and nuclear plants and 18,000 from wind and solar power, according to the Texas Electrical Reliability Council, which operates the state’s power grid.

“Every one of our power supplies underperformed,” said Daniel Cohan, associate professor of civil and environmental engineering at Rice University in Houston, tweeted. “Each of them is vulnerable to extreme weather and climate events in different ways. None of them were adequately heated or prepared for a full range of weather and conditions. “

The staggering imbalance between Texas power supply and demand also caused prices to skyrocket from about $ 20 per megawatt hour to $ 9,000 per megawatt hour in the state’s free wholesale power market.

That raised questions about whether some power generators buying on the wholesale market may have had a profit motive to avoid buying more natural gas and simply shutting down.

“We can’t speculate on people’s motivations in that way,” said Bill Magness, ERCOT CEO. He added that the generators had told him they were doing their best to provide power.

WHY WASN’T THE STATE PREPARED?

Gas plants and wind turbines can be protected against winter weather; it is done routinely in the colder northern states. The problem emerged in Texas after a 2011 freeze that also led to power plant shutdowns and blackouts. A national electrical industry group developed winterizing guidelines that operators must follow, but they are strictly voluntary and also require expensive investments in equipment and other necessary measures.

An ERCOT official, Dan Woodfin, said the plant upgrades after limited 2011 shutdowns during a similar cold snap in 2018, but this week’s weather was “more extreme.”

Ed Hirs, a University of Houston energy fellow, rejected ERCOT’s claim that this week’s freeze was unpredictable.

“That is silly,” he said. “Every eight or ten years we have really bad winters. This is not a surprise.”

In California, regulators last week ordered the state’s top three utilities to increase their power supply and possibly make plant upgrades to avoid another supply shortage like the one that emerged in California six months ago. and it resulted in continuous blackouts that affected some 500,000 people for a few hours at a time.

“One big difference is that the leadership in California recognizes that climate change is happening, but that doesn’t seem to be the case in Texas,” said Severin Borenstein, a professor of business administration and public policy at the University of California, Berkeley, who has been studying power supply problems for over 20 years.

WHY ROLLING BLACKOUTS NEEDED?

Grid operators say continuous blackouts are a last resort when energy demand overwhelms supply and threatens to create a broader collapse of the entire electrical system.

Generally, utilities lock down certain blocks or zones before shutting off power to another area and then another. Often times, areas with hospitals, fire stations, water treatment plants, and other key facilities are spared.

With blackouts, no neighborhood is supposed to go an unfairly long period without power, but that wasn’t always the case this week in Texas. Some areas never lost power, while others were left off for 12 hours or more when temperatures dropped to single digits.

WHEN DOES IT HAPPEN?

Ongoing blackouts are usually triggered when stocks drop below a certain level. In Texas, as in California last August, network operators are telling utilities to reduce the load on the entire system, and it is up to the utilities to decide how to do that.

In Texas this week, network operators and utilities knew of the dire weather forecast for at least a week. They issued calls for energy conservation last weekend, with ERCOT tweeting that residents should “unplug the fancy new appliances they bought during the pandemic and only used once.”

The carefree attempts at humor were lost on residents, few or none of whom were informed in advance when their homes would lose power. Once the outages began, some utilities were unable to provide information on how long they could last.

WHAT CAN BE DONE TO REDUCE ROLLING BLACKOUTS?

Start with the obvious steps: When power companies or network operators notice trouble ahead, turn down the thermostat and avoid using large appliances. Of course, those steps are sometimes easier said than done, especially during record temperatures.

As elsewhere, Texans might be more willing to adjust their thermostats a bit more if regulators impose a system that requires households to pay higher prices during peak demand periods and lower rates at other times.

“People light their furnaces now because there is no financial incentive for them not to,” Borenstein said.

Experts also say more fundamental and costly changes must be made. Generators must insulate pipes and other equipment. Investments in electricity storage and distribution would help. Tighter building codes would make houses in places like Texas better insulated from the cold.

Texas, which has a network largely disconnected from others to avoid federal regulation, may have to rethink going solo. There could be pressure for the state to require power generators to keep more plants in reserve for times of peak demand, a step it has so far resisted.

“The system as we built it is not performing to the standards we would like to see,” said Joshua Rhodes, an energy researcher at the University of Texas at Austin. “We need to do a better job. If that means paying more for energy to have more reliability, that’s a conversation we’ll have to have. “

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Koenig reported from Dallas, Liedtke reported from San Ramon, California. AP’s Paul Weber contributed to this story from Austin, Texas.

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