E2: Do wind turbines freeze up in the cold?

LHF: Hello from the Massachusetts Institute of Technology and welcome to Today I Learned: Climate. I’m Laur Hesse Fisher. And in our next two episodes, we’ll be answering a pair of questions from Julie G. of California, who is passing on some concerns she’s heard about wind power. Does it stop working in cold weather? And do wind turbines kill birds? 

This is technology we’re adopting really quickly—in fact, wind power has become our leading source of renewable energy, providing 10% of all electricity in the United States. So we definitely want to know the different kinds of challenges that accompany wind power.

So Julie, to help answer your questions, we talked to Prof. Michael Howland of the MIT Department of Civil and Environmental Engineering, who studies ways to make renewable energy systems more efficient and reliable. And in this episode, he’s going to help us understand how wind energy behaves in cold weather. Do the wind turbines just… freeze up?

MH: Wind turbines are a robust electricity generation technology that work on land, offshore, and in extreme conditions, including extreme cold. But if specific turbines are not appropriately protected for cold conditions, extreme cold temperatures can cause wind turbine blades to ‘ice,’ where ice builds up on the wind turbine blades and affects the aerodynamics and forces on the turbine.

LHF: And that ice buildup can slow the turbines down, or stop them altogether. So for instance, you might remember the terrible Texas cold front in 2021, which took down electrical systems and led to the deaths of at least 240 people. 

ABC News: Millions of Americans across 11 states waking up without power this morning, 4 million in Texas alone. That state is seeing as you said an historic cold snap and Marcus Moore is in Dallas with the latest. More than 4 million people waking up in the Lone Star State without power. Officials imposed rolling blackouts, saying the lack of energy is due in part to frozen wind turbines in West Texas knocked offline.

LHF: That was from ABC News on February 16, 2021. And those early reports were true—mostly. During the storm, some wind farms did stop producing electricity because their turbines iced over.

But they also left some important things out.

Extreme cold weather can affect many parts of our energy system—not just wind power. And as later investigations would make clear, the biggest reason for the energy crisis in Texas that winter was not frozen wind turbines. Texas saw a much bigger shortfall in energy from natural gas, which supplies most of the state’s electricity. Both the wind farms and the natural gas supplies failed for pretty much the same reason: they had not been “weatherized” for extreme cold.

MH: The primary issue with the wind turbines in Texas is that such extreme cold was not expected based on the historical record of weather, and therefore the developers did not weatherize the wind turbines. Wind turbines operate effectively in much colder locations than Texas, including Canada, Sweden, Alaska, etc.

LHF: Yeah, right now, as you listen to this podcast, there are even wind turbines providing reliable power in Antarctica to help power research stations. These turbines have weatherizing technologies like water-resistant coatings, and heaters to repel and melt ice. Turbines that are engineered in this way can keep working at temperatures down to -22° Fahrenheit.

We use these technologies here in the U.S., too. They’re why the Great Plains, the Upper Midwest and New England can make use of wind energy year-round. In fact, data show that wind turbines actually produce more energy in these regions in the winter.

So in general, we can safely rely on weatherized wind power in cold climates. But it’s understandable why Texan energy companies didn’t weatherize their turbines. This stuff costs money—adding about 5 to 10% to the cost of a wind turbine. So the Texas experience in 2021 tells us something crucial about how we might want to plan energy infrastructure in the future.

MH: Since extreme weather is increasingly affected by climate change, we may need to revisit which locations require wind turbine weatherization.

LHF: We did a whole episode on climate change and extreme cold weather in our fourth season, called TIL about winter storms—and we learned that there are places, including Texas, that are likely to see occasional outbreaks of extreme cold weather as on average the planet warms. And energy companies in those places may need to rethink the cost-benefit of weatherization. Not just for wind turbines, but for all their energy sources, and even the transmission lines that carry electricity from where it’s produced to where it’s used. Those, too, can get iced over or torn down in storms.   

Texas, for one, has made some changes, as the legislature passed new weatherization requirements for ERCOT, the state’s electric grid operator.

KLTV: Ahead of a frigid forecast, the CEO of ERCOT says the state’s power grid is ready for high demand.

CEO: We’ve completed nearly 1800 weatherization inspections across power generation and transmission facilities over the past couple of years. We’re on track to do 450 this winter alone, to ensure that everybody is weatherized and prepared to get through this weather event.

LHF: And other regions may want to take notice too, before they face major blackout events. Building an overall more resilient electric grid that’s prepared for the weather of the future will help prevent outages—whatever energy sources we choose to use.
So thank you, Julie, for the question. And stick around for our next episode, where Prof. Howland will also tell us what wind energy means for birds.

Do you have a question about climate change? Maybe we answered it as part of our Ask MIT Climate series at climate.mit.edu. If we haven’t, ask us! Visit https://climate.mit.edu/ask or leave us a voicemail message at 617 253 3566. We release answers as episodes here on TILclimate as well as at climate.mit.edu. 

And we love hearing from our listeners! Send us a message at climate@mit.edu, and let us know who you are, what you’re working on, and why you listen to the show. We so look forward to hearing from you.

TILclimate is the climate change podcast of the Massachusetts Institute of Technology. Aaron Krol is our Writer and Producer. David Lishansky is our Sound Editor and Producer. Michelle Harris is our fact-checker. Sylvia Scharf is our Climate Education Specialist. The music is by Blue Dot Sessions. And I’m your Host and Executive Producer, Laur Hesse Fisher. 

A big thanks to Prof. Michael Howland for speaking with us; to Julie, for asking us her questions; and to you, our listeners. Keep up the curiosity.