By Adam Wagner for The News Observer
Originally posted 01/04/2025
Duke Energy is poised to replace some coal-fired power plants with gas-fired stations at two North Carolina sites after receiving key approvals from environmental and utility regulators.
Under the plans, Duke will replace two of the four coal-fired units at Person County’s Roxboro plant with gas-fired combined cycle units by 2029. Combustion cycle units generate power consistently, helping utilities like Duke meet their baseload needs.
At Catawba County’s Marshall plant, Duke currently operates four coal-fired units that can also generate electricity by burning natural gas. Two of those will be replaced by a pair of gas-fired combustion turbines that utilities use to meet demand when it peaks.
The N.C. Utilities Commission issued orders in early December deeming the gas plants necessary at both sites. That was followed by a Dec. 20 decision by the N.C. Department of Environmental Quality granting air quality permits for the gas-fired plants, with some conditions.
“We appreciate the support of Person and Catawba counties. We look forward to working together as we transition to cleaner energy in a manner that keeps North Carolina’s economy thriving, while continuing to protect grid reliability and affordability for our customers,” Bill Norton, a Duke Energy spokesman, said in a written statement.
Duke has maintained that as it moves away from burning coal to generate electricity, it must use natural gas as a stable, reliable fuel source to meet growing demand instead of shifting more of its generation to solar- and wind power. That claim has been met with skepticism among the environmental community, which favors a quicker shift to renewable fuel sources rather than building new gas-fired plants that they argue could become quickly outdated even as they emit methane, a potent greenhouse gas.
Notably, while the N.C. Utilities Commission cleared the path for both projects as parts of its joint carbon dioxide reduction and resource planning process, they would both result in large increases in total greenhouse gas emissions.
At Roxboro, the changes would increase greenhouse gas emissions from about 7 million to 12.86 million tons per year, an 83.67% increase. At Marshall, the new gas units would emit 5.6 million tons of greenhouse gases per year, compared to 2.1 million tons from the two units they are replacing.
That is evidence of what many environmental groups see as a flaw in the state law requiring Duke to work with the Utilities Commission to balance slashing carbon dioxide emissions with affordability and reliability. The law does not include any language about methane or other greenhouse gases.
“We are disappointed that the two permits have been granted and we’re hopeful that steps can be taken to address what we see as unfortunately an increasing trend for more and more gas to be built out in our state, which is contrary to what state law requires and is contrary to the state’s overall clean transition objectives,” Munashe Magarira, a Southern Environmental Law Center senior attorney, told The News & Observer.
Pollution controls?
Greenhouse gases aren’t the only pollution environmental groups were concerned with from the gas-fired plants.
The new permits will slash pollutants often associated with burning coal such as nitrogen oxides and sulfur dioxide. At Roxboro, for instance, those will be reductions of 4,130 and 3,676 tons per year.
But swapping some coal for new natural gas will lead to increases in other pollution at the two facilities. The Roxboro plant’s emissions of volatile organic compounds, for instance, would climb from 80.6 to 720.1 tons per year. And the 63 tons of volatile organic compounds coming from the new natural gas facilities at Marshall would more than double the 30 tons emitted annually from the coal units they will replace.
“The permits in their current form and condition still would expose surrounding communities to significant harmful pollution and harm people’s health,” Magarira said.
The Southern Environmental Law Center argued that DEQ could have avoided those increases by deeming the natural gas plants a new project instead of a modification of the existing power stations, thus subjecting them to a more stringent set of pollution control rules.
In documents responding to public comments, DEQ argued that the projects don’t trigger the stricter standards because they are part of the same kind of industrial activity as what is already happening on the sites, belong to the same owner and are being built on the same property.
Additionally, the Southern Environmental Law Center told DEQ the permits should include specific dates identifying when Duke would retire the coal-fired facilities, ensuring that they would no longer be used and thus their pollution no longer generated once the gas plants are built.
“That language is altogether missing form the permit even though there is some language about the coal plants being retired at some point,” Mararira said.
At Marshall, DEQ included a condition stipulating that Duke shut down two coal-fired boilersonce the combustion turbines are operational. At Roxboro, Duke acknowledged that after 2029, there will be a “short” period of time where all four coal-fired units and the two new natural gas units are in operation, giving the facility a total output of more than 4,000 megawatts until two of the coal plants are retired.
This story was produced with financial support from the Hartfield Foundation and Green South Foundation, in partnership with Journalism Funding Partners, as part of an independent journalism fellowship program. The N&O maintains full editorial control of the work. If you would like to help support local journalism, please consider signing up for a digital subscription, which you can do here .