Coal-fired power failures during winter storm come to light months later

Utility exec told lawmakers that a frozen gas pipeline was to blame. PSC filings reveal the rest of the story.

By: - September 8, 2023 5:50 am

About 35,000 customers experienced rolling blackouts last Dec. 23 when LG&E and KU had to reduce supply to avert wider power outages. (Photo by iStock/Getty Images Plus)

Last December a mass of arctic air, later unofficially named Winter Storm Elliott, swept through Kentucky plunging temperatures to as low as eight degrees below zero. The frigid weather led to a power supply crunch across the Southeast as households and businesses tried to stay warm. 

Louisville Gas and Electric and Kentucky Utilities, the state’s largest utility with more than a million customers, had to implement rolling blackouts for more than 35,000 customers for the first time in its leadership’s recent memory to meet the unprecedented demand for power.

Less than six weeks later, speaking to Kentucky lawmakers, the utility’s chief operating officer blamed a frozen natural gas pipeline for the rolling blackouts. 

What he did not mention was that coal-fired power also had failed — enough so that if the utility’s coal-fired generation had been operating at capacity the rolling blackouts would have been averted. That became clear during a recent Kentucky Public Service Commission (PSC) hearing on LG&E and KU’s plans for the future. 

During the multi-day hearing last month, the utility’s chief operating officer Lonnie Bellar for the first time in a public setting detailed how several LG&E and KU coal-fired units couldn’t perform at full capacity or were taken offline because of the extreme temperatures or separate mechanical issues.

In February, lawmakers in part cited Bellar’s testimony about the frozen gas pipeline and rolling blackouts as evidence of coal’s superior reliability as a power source. The Republican-controlled General Assembly soon after passed a law, Senate Bill 4, to make it harder for utilities to retire fossil fuel-fired power generation, including from coal. The law created a series of prerequisites before the Kentucky Public Service Commission could allow utilities to retire fossil fuel-fired power generation.

Jim Gooch. (LRC photo)

Rep. Jim Gooch, the staunchly pro-coal chairman of the House Natural Resources and Energy Committee, said this week he isn’t sure why Bellar in February told the committee nothing about the failure of coal-fired generation during the winter storm. Gooch, R-Providence, said knowing of the omission does not change his belief that the rolling blackouts were caused by the “rush” to close coal-fired power plants. 

“That’s why we’ve passed Senate Bill 4,” Gooch said in an interview with the Lantern. “That’s why (LG&E and KU is) having to go before the PSC now to say that, you know, if they do close these plants, that it will not affect reliability and affordability.”

LG&E and KU also could have averted the rolling blackouts if it had been able to buy power from nearby utilities and electric grid managers, which were also feeling a power crunch during the winter storm. The utility’s hydropower had outages from the weather, too, though the facilities provide only a small amount of power.

Challenging reliability rhetoric

During the PSC hearing, Kate Huddleston, an attorney for the Sierra Club, asked about the coal-fired failures. The utility’s managers, including Bellar, characterized them as expected and acceptable outages. 

But some renewable energy advocates and energy analysts say normalizing the coal-fired power failures during the winter storm ignores the reliability problems fossil fuel plants can have during extreme weather, weaknesses that challenge rhetoric by Republicans that coal-fired power is the most reliable source of energy. 

Cassie Chambers Armstrong (LRC photo)

Sen. Cassie Chambers Armstrong, D-Louisville, a member of the Kentucky Senate Natural Resources and Energy Committee, wasn’t  part of the legislature during the February hearing; she replaced Democratic Congressman Morgan McGarvey in March. 

She and almost all Democrats in the GOP-controlled legislature opposed SB 4 when it passed. She said the law took away flexibility to create a more diversified energy grid, including the addition of renewables. Kentucky has the lowest percentage of electricity generated by wind and solar energy in the country. 

She said Kentuckians have the right to understand “exactly what happened that led to utility shutdowns.”  

“We know that in other places, failures of coal-fired power plants were part of the problem that led to these blackouts. We deserve to know in Kentucky if that was part of it as well,” Chambers Armstrong said.

What happened last winter when fossil fuels failed

When LG&E and KU issued rolling blackouts on Dec. 23, 2022, it was in an effort to “offload” or reduce power consumption to match its limited electricity supply to prevent even wider, longer blackouts. 

An internal LG&E and KU report filed with the PSC details that the rolling blackouts offloaded at most 317 megawatts of electricity from 5:58 p.m. EST to 10:11 p.m. EST on Dec. 23.

A utility spokesperson maintains the “major driver” of the rolling blackouts was the “unexpected loss” of its natural gas plants at the Cane Run Generating Station (Cane Run) and the Trimble County Generating Station (Trimble County) — caused by a loss of pressure from the Texas Gas Transmission pipeline supplying those plants. 

“This was the first ever load shed event for our company and customers in our more than 100 years in operation,” said LG&E and KU spokesperson Chris Whelan in a statement. 

That loss of gas pressure began, according to the utility’s internal report, a little after 11 a.m. EST on Dec. 23, and it started to impact its gas plants in the early afternoon. 

  • 179 megawatts of power was lost when a gas generating unit went offline at Trimble County.
  • The rest of the operating gas turbines at Trimble County collectively lost 439 megawatts of power generation due to the low gas pressure.
  • A gas generating unit at Cane Run also lost 253 megawatts of power due to low gas pressure.

In total, the lost power due to failing gas plants totaled 871 megawatts, more than double the 317 megawatts of power the utility had offloaded during the rolling blackouts. 

“We were trying to manage that minimum pressure and not lose the generation that we did have, at the same time getting as many megawatts out of our machines as we possibly could,” Bellar said during PSC testimony on Aug. 22. 

But had the utility avoided some of the problems it faced with its coal-fired power plants during Winter Storm Elliott, it also could have avoided rolling blackouts. Those issues included:

  • Trimble County Unit 1 was the utility’s most active power generation unit in 2022 operating the equivalent of nearly 10 months out of the year. But the unit’s 370 megawatts of coal-fired power was taken offline the afternoon of Dec. 22 because of a failure of a gearbox that the utility said was unrelated to the weather. 
  • Trimble County Unit 2, also coal-fired, lost 269 megawatts of power generation for more than six hours into the evening of Dec. 23 due to a “frozen” transmitter that tripped a coal mill at the unit. 
  • A coal-fired unit at the utility’s Mill Creek Generating Station lost 121 megawatts of power generation for almost three hours the afternoon of Dec. 23 due to frozen components in the unit’s coal delivery system.
  • The utility lost 62 megawatts of power capacity from its sole coal-fired power generation unit at its E.W. Brown Generating Station due to problems with “combustion process instrumentation” the utility believes wasn’t weather-related

In total, more than 800 megawatts of LG&E and KU’s coal-fired power generation was offline at some point, due to mechanical issues or weather issues, during the time when it was implementing rolling blackouts — more than double the 317 megawatts the utility offloaded during the storm. 

Bellar in Aug. 22 PSC testimony disputed the assertion that LG&E and KU couldn’t count on its coal-fired power during Winter Storm Elliott, saying he wouldn’t “point the finger solely” at coal-fired power as the cause of the rolling blackouts. 

“No asset is perfectly available all the time,” Bellar said. 

In separate testimony on Aug. 23, LG&E and KU’s Director of Energy Planning, Analysis and Forecasting Stuart Wilson called the coal issues not an “exceedingly poor performance.”

LG&E and KU’s hydropower dams also had trouble; the Ohio Falls Generating Station was taken out of commission for much of Dec. 23 due to “inclement weather issues.” Because of the high demand across the region, other sources of power weren’t available to buy from the Tennessee Valley Authority or PJM Interconnection.

While the utility has taken several steps to address issues with pressure to its natural gas plants, Wilson said he wasn’t aware of any steps the utility had taken to address problems with its coal-fired power. 

E.W. Brown solar array at KU’s Mercer County plant. (Photo courtesy of LG&E/KU)

The energy debate, consequences before the PSC

LG&E and KU was far from the only utility that experienced problems with coal-fired power during Winter Storm Elliott. 

A March 2023 report from the Institute for Energy Economics and Financial Analysis (IEEFA), a research group that supports the transition to renewable energy, found that more than 100,000 megawatts of fossil fuel-fired power generation failed to start or was forced offline for utilities and grid managers across the Eastern U.S., including the Tennessee Valley Authority, PJM Interconnection and the Electric Reliability Council of Texas. 

Renewable energy, on the other hand, generally met or exceeded power generation expectations during the storm. 

The TVA, which provides electricity to Western Kentucky, also had to implement rolling blackouts in part due to a few of its coal-fired and natural gas generators n failing in the extreme cold. Its solar energy facilities, which only make up 3% of the TVA’s generation, did perform consistently during the storm. 

MISO, a nearby regional grid operator to LG&E and KU, also had a significant amount of wind power available during the storm that helped supply electricity to Kentucky utilities.  

Dennis Wamsted, an energy analyst with IEEFA who authored the report on fossil fuel outages, said regardless of how utilities frame the issue, not having power generation when it’s “desperately needed” is a problem. 

“The argument from utilities and folks in the gas and coal sector — that somehow gas and coal are reliable, dispatchable resources,” he said. “You can only make that argument if your plant is actually reliable and dispatchable when it’s needed. And so if you weren’t able to dispatch your coal plant on the coldest day of the year, you cannot claim that you are a dispatchable resource.”

The details surrounding LG&E and KU’s power generation challenges during Winter Storm Elliott come as the utility is trying to retire some of its coal-fired generation units and largely replace them with natural gas plants. The utility is citing future emissions regulations and aging units that utility leaders say make it uneconomical to run three of its coal units, reflecting a trend of utilities across the country retiring coal power in light of cheaper alternatives such as natural gas and renewables. 

But with the implementation of SB 4, LG&E and KU now needs the explicit approval of the PSC before it can retire some of its coal power. Investor-owned utilities, including LG&E and KU, strongly opposed the legislation stating that it would force them to keep running uneconomical coal plants past their reasonable lifespans and burden consumers with maintenance costs. The utility states its proposal meets the requirements of the new law. 

A coalition of Kentucky-based renewable energy and environmental conservation groups, including the Kentucky Solar Energy Society and the Mountain Association, are intervening in the PSC case pushing LG&E and KU to invest more in renewable energy instead of building natural gas plants and adopt more robust energy-savings programs for ratepayers. 

Thom Cmar, an attorney with the environmental legal group Earthjustice representing the groups, said LG&E and KU “normalizing” the failures of fossil fuel-fired power generation ignores the possibilities for renewable energy and creates a “false choice” between natural gas and coal. 

He argues solar installations paired with utility-scale batteries, for example, can dispatch energy when needed and create a more reliable energy system. 

“A big part of the problem is if you’re only relying on one big fossil fuel plant or a small number of big fossil fuel plants to get your electricity, then you’re uniquely at risk for when one of those plants fails. And we know that they do fail,” Cmar said. 

Renewable energy experts say that solar and wind power can be just as reliable as fossil fuels with the need for continued investments in battery storage to capture energy from renewables.

Climate concerns

Another large concern for the coalition of groups is the heat-trapping greenhouse gas emissions that contribute to climate change created from new natural gas plants, compared to emissions-free renewables. The leader of the United Nations, citing research from climate experts, is calling on rich countries including the United States to end all use of coal and natural gas for electricity generation by 2035 to limit the impacts of climate change. 

The utility has stated retiring its power generation in favor of an all-renewable supply would cost about $2 billion more. Its proposed natural gas plants, the utility stated, would produce 65% less carbon dioxide emissions compared to the coal-fired power slated for retirement. 

While natural gas produces about half the carbon dioxide when burned compared to coal, climate scientists worry the increasing adoption and emissions of the fuel could guarantee worsening climate change impacts in the future. Producing natural gas also emits methane, a greenhouse gas significantly more potent at warming the atmosphere in the short-term than carbon dioxide.

Along with its coal retirements and natural gas plants, LG&E and KU is proposing to build two solar installations, buy even more solar power through purchase agreements and build a small battery storage facility. Coal and natural gas would still be the utility’s main sources of power generation under the proposal. 

Whelan, the utility spokesperson, didn’t directly answer when asked why Bellar did not mention the utility’s problems with coal-fired power before lawmakers in February

The internal utility report which detailed the coal-fired power problems, Whelan said, wasn’t provided directly to the legislature but has been available publicly as an online filing on the PSC’s website. The link to the report is one of hundreds of links to filings made by the utility and other stakeholders in the PSC case. 

Whelan said power generation is designed to withstand extreme conditions like “bitterly cold temperatures,” but such conditions do create challenges. 

“We strive for 100% reliability but rely on our portfolio of generating assets rather than any one unit,” Whelan said. 


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Liam Niemeyer
Liam Niemeyer

Liam covers government and policy in Kentucky and its impacts throughout the Commonwealth for the Kentucky Lantern. He most recently spent four years reporting award-winning stories for WKMS Public Radio in Murray.