NC, federal regulators seek answers from Duke Energy on Christmas Eve blackouts

On Tuesday, for the second time in a month, Duke Energy officials will come before North Carolina regulators to address events that left thousands without power.

In December, the North Carolina Utilities Commission questioned Duke Energy about the attacks on electrical substations that put more than 40,000 Moore County residents in the dark for days. This week, regulators will ask the state’s largest electrical provider about the unprecedented rolling blackouts that affected around half a million customers Christmas Eve morning during one of the state’s coldest weekends in recent years.

The outages have sparked widespread concern about the reliability of the regional electrical grid. Duke Energy spokesperson Bill Norton said the company had never before deployed rolling outages of that magnitude in the Carolinas. On Wednesday, the Federal Energy Regulatory Commission in Washington announced it was opening an investigation into what led to the blackouts.

Duke Energy has confirmed that multiple power plants functioned abnormally during the early morning of Dec. 24, which when combined with greater energy demands due to the low temperatures, prompted the outages.

“The majority of our generating units performed as expected, but some units did not generate power or operated at reduced capacity in the pre-dawn hours on Christmas Eve,” Norton told The Charlotte Observer. “The power output was lower than we expected — we’re still evaluating why.”

Norton said Duke Energy, which is headquartered in Charlotte, was banking on receiving power from independent producers and out-of-state energy purchases, plans which collapsed when those providers were similarly stressed by extreme weather.

When energy demand exceeds input, providers implement rolling blackouts to ration available power to the greatest number of customers, said Leonard White, a professor of electrical engineering at N.C. State University.

“Think about it like having a house with five rooms and four flashlights,” he said. “You move them from room-to-room so that no one is in the dark all night.”

Fossil fuels vs. renewable energy

White added that solar power doesn’t produce energy before the sun rises. And in the days since the Christmas Eve blackouts, some state leaders have placed blame on solar and other renewable energy sources.

“For some reason, policymakers around the nation and literally around the world think it’s got to be wind, it’s got to be solar, which again, are unreliable intermittent sources,” Sen. Paul Newton said during an interview with Spectrum News which aired Thursday. Newton is a former Duke Energy executive and a Cabarrus County Republican who serves as the Senate’s majority leader.

But others have pointed out that energy generated by nonrenewable sources flagged for Duke Energy around the time of the outages. Data from the Energy Information Administration shows the energy the company generated from natural gas and coal sources fell during the morning of Dec. 24.

The Utilities Commission’s Public Staff, which represents consumers in matters before the commission, has asked Duke to address which specific units were impacted on Christmas Eve. As of Monday, it had not received an answer.

“We are aware of people referencing Dan River (gas) and Mayo (coal) going down, but have not received confirmation from Duke,” said Chris Ayers, the Public Staff’s executive director, in an email to The News & Observer.

The Dan River plant is in Rockingham County while the Mayo coal plant is in Person County.

Ayers noted additional Duke nuclear and coal plants were either out or operating at reduced capacity going into the week before Christmas.

NC’s Public Staff, governor wait on specifics

The Public Staff won’t get to question Duke Energy officials Tuesday, but Ayers said he hopes the Commission uncovers “material facts that will help us understand exactly what happened, why it happened, and how we can avoid outages if presented with a similar situation later this winter.”

The N.C. Utilities Commission is tasked with overseeing the state’s public utilities. Each of its seven members is appointed by the governor and confirmed by the General Assembly to serve a six-year term. The commission is also in the process of adjudicating Duke Energy’s recent requests for multiyear rate increases.

Over Christmas weekend, Gov. Roy Cooper said he was “deeply concerned” about those who lost power without prior notice from the utility. Utilities Commissioner Floyd McKissick Jr. told The N&O he shares the governor’s desire to know more about the notification process.

“I think the governor’s questions have been extremely reasonable, and I expect to hear full, complete, expansive responses from the Duke team relating to the issues raised by the governor concerning accountability,” he said.

But McKissick, a former state senator, was very intentional not to place blame until more is known about the events on Christmas Eve morning.

“There’s a lot of complexity to it,” he said. “They’re not simple answers. And I fully respect all that (Duke Energy) did under very challenging circumstances. I think what we can always do is determine what was unanticipated that occurred and what we can always do better.”

This story was produced with financial support from a coalition of partners led by Innovate Raleigh as part of an independent journalism fellowship program. The N&O maintains full editorial control of the work.

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