When cold coal froze, wind farms helped Evergy power Kansas through winter weather


Evergy maintained “normal operating conditions for extreme weather,” despite coal freezing, thanks in part to high winds powering wind farms through the recent blustery conditions.

“The bottom line is we had enough power over the last week or so and in particular through the weekend when we had the coldest weather to meet demands,” said Chuck Caisley, an Evergy executive, about the previous weekend.

He added that with a midweek warming, “I think we are out of the biggest danger of not having adequate supplies.”

Caisley told the House Energy, Utilities and Telecommunications Committee on Tuesday that “the system has held up” and contrasted the current wintry weather with what happened in February 2021 with winter storm Uri.

Cold coal froze in Kansas winter

“Probably the biggest difference for us in this storm versus Uri was about a week to 10 days prior to this event, you’ll recall, we had sleet, ice, snow and even rain in some parts of the service territory,” Caisley said. “And what that means is even though we put sealant on our coal piles, we had a lot of frozen coal — both that’s operating within our coal plants but also just lying on the ground, which makes running those coal power plants a lot more difficult.

“For all the great technology that we have when it comes to combating frozen coal and just frozen equipment in general, it’s really pretty caveman-type implements that we use. We use fire. We use blow torches. We use jackhammers. We use sledgehammers. We use Bobcats. And we just simply try and break it up.

“But what happens is sometimes it does freeze in the hoppers and in the coal bins. We can’t pulverize it. And either we have to take a unit offline, heat that coal up and then get it going again, or we take what’s called a derate, which means it’s not running at full capacity. You can’t get the same amount of power out of it. And that happened periodically to some of our coal plants.”

Wind farms benefited from the wind chills

While people who had to be outside may not have enjoyed the sub-zero wind chills, that windy weather helped keep the lights on inside.

“The good news is that unlike Uri where it was really, really calm, the wind has been blowing like blue blazes, which means we have been getting thousands of megawatts from our wind production facilities across Kansas,” Caisley said. “The only problem with that is it fluctuates.”

The significant fluctuations in wind production means a need for “dispatchable power in order to pick it up, or the lights go out and you can’t make things anymore, people lose heat and it’s a bad situation.”

Natural gas price spikes weren’t as high

While natural gas saw price spikes during this storm, they were nowhere near the skyrocketed prices from Uri that resulted in alleged price gouging lawsuits.

“From a natural gas perspective,” Caisley said, “we didn’t see the fuel spikes that we saw in Uri, and we able to procure for natural gas for a significant amount of our generation that uses it ahead of time.”

Wolf Creek nuclear power plant ‘cruised’ in winter weather

“Our nuclear plant Wolf Creek, 80 miles from here, cruised through this whole event,” Caisley said.

Transmission and distribution saw small outages

Caisley said the distribution system has operated normally with occasional outages affecting a relatively small number of people.

“That’s when a line drops because it starts galloping in the wind or it has some kind of an electromechanical failure,” he said. “What happens is ice gets in some of these moving parts and expands and just breaks things. So that’s expected. We’ve had that on and off. Usually, those are about 1-2 hour outages.”

There was a bigger outage across the state line near the Truman Sports Complex. It happened during the Kansas City Chiefs playoff game against the Miami Dolphins.

“We actually had a cable between two transformers in one of the substations that serves Arrowhead Stadium burn up,” Caisley said. “Fortunately, it was not one of the transformers that serve Arrowhead. Unfortunately, we lost a lot of capacity to distribute power in that area and it took about 3 hours to get about 11,500 Missouri customers up.”

Importing and exporting electricity

The worst of the winter weather affected a narrower slice of the Midwest at a time than Uri did.

“We were able to import power from our neighbors to the east, which was unavailable in winter storm Uri,” Caisley said. “So MISO, which is the regional transmission organization immediately to our east and going up into the northern parts of the Midwest, we actually imported, both SPP and Evergy, imported some power from them over the last several days.

Now, as this system moves east, we expect that we will return the favor and the Southwest Power Pool and Evergy will offload electricity and sell to them.”

Will the winter storm cost ratepayers?

Caisley said “it’s too early to tell” if ratepayers will see a bump in their electric bill as a result of the winter weather.

Uri resulted in increased electric bills for Evergy Kansas Central customers, which includes Topeka, but decreased bills for Evergy Kansas Metro customers due to cost savings from exporting power to other utilities.

“Because we don’t know what MISO is going to ask for yet, and because we don’t have the bill tabulated for last three or four days, I can’t tell you how that’s going to wash out,” Caisley said. “But I would say we’re in a very good position, particularly if the wind keeps blowing, to export power to our neighbors. Hopefully that offsets some or completely or maybe even puts us in a beneficial position over the coming two or three, four days.”

Kansas faces elevated reliability risks

But Caisely’s presentation wasn’t all sunshine and rainbows, advising legislators that federal regulators have the Southwest Power Pool at elevated risk in both a winter reliability assessment and a long-term reliability assessment. Those reports warn of a potential for insufficient reserves during extreme weather conditions.

For Evergy Kansas, the excess capacity is about 400 megawatts — which is equivalent to about four wind farms or about half a coal power plant. But that excess is expected to evaporate by the end of the decade due to various factors, including new large customers like Panasonic and the scheduled retirement of a Lawrence coal unit.

That Lawrence facility is slated to close in 2028, but Evergy would likely keep it open “as long as that is a viable plant from a cost perspective and as long as we need the generation,” Caisley said. But Environmental Protection Agency requirements that are being litigated could requires “hundreds of millions of dollars” worth of environmental controls to that plant, making it not “financially viable to operate anymore.”

More generation is needed before 2030, Caisley said. Evergy wants to build combined cycle natural gas plants.

“Right now, coal is not viable to build,” he said. “Natural gas is.”

Evergy wants to have renewables and fossil fuels

While he said fossils fuels are under “duress,” particularly from the federal government, he also said “our federal government is a reflection of our society at the end of the day, and so we’ve got a lot of customers that don’t like fossil fuels either.”

“And at the end of the day, it is also true that a diverse generation mix is helpful,” Caisley said. “So I mean, our wind over the last week has played a significant role in keeping the lights on. Now, it fluctuates so much that it’s good to have baseload dispatchable generation underneath it. And by and large, that is fossil fuel derived right now.”

As reported in the Topeka Capital Journal


  1. Fascinating read! It’s great to see how wind farms can help mitigate the impact of extreme weather events like frozen coal. As someone who cares about sustainable energy sources, I appreciate the innovation and resilience of Evergy’s approach. Keep up the good work!


Please enter your comment!
Please enter your name here