In Sept. 17 statement, the Sierra Club commended Duke Energy for acknowledging its “responsibility to lead in the effort to decarbonize our economy,” but it and some other environmental groups criticized some of Duke Energy's plans, especially opening new natural gas power plants as it phases out coal.
Emissions data from energy consulting company M.J. Bradley & Associates show Duke Energy was the country’s largest electricity generator in 2017, and among the country’s power generators, it was the single biggest emitter of both carbon dioxide and nitrogen oxides.
Jim Warren, executive director of the nonprofit NC WARN, said Duke Energy is a monopoly that is "going the wrong direction" and doing what he called greenwashing — “a major, calculated deception” of the public.
Warren said Duke Energy is right that burning natural gas releases less carbon dioxide than does burning coal. But natural gas, he said, contains mainly methane, which traps atmospheric heat much more than carbon dioxide does.
Lots of unburned methane, he continued, gets released during natural gas fracking and distribution, and though causation isn’t certain, recent increases in fracking are correlated with rapidly rising global temperatures.
“Building a huge amount of additional fossil fuel infrastructure, in what’s nearly 2020, is just nuts,” Warren said.
Natural gas plants, he said, are made to run for decades.
Erin Culbert, a spokesperson for Duke Energy, said the company has worked to minimize methane leaks, adding that innovations in carbon capture might also lower the impact of burning natural gas.
She said energy storage technology today is insufficient to let the company use only solar, so natural gas, cheaper than coal, is needed to transition from coal.
“We are a fan of having a very diverse mix of energy sources for customers," Culbert said, referring to the economics of natural gas vs. renewables. "We don’t really prefer one over the other."
In statements on Duke Energy's website, some environmental advocates congratulated Duke for its announcement last week. Bob Perciasepe, president of the Center for Climate and Energy Solutions and the EPA’s deputy administrator in the Obama administration, said “it’s critical that electricity providers lead the way” in reducing greenhouse-gas emissions.
Duke Energy indicated that commercial technologies today are inadequate to reach its 2050 net-zero goal.
Besides opening natural gas plants, the company said it will continue promoting energy efficiency and installing electricity meters in homes. Both the main company and a subsidiary, Duke Energy Renewables, work to grow solar and wind energy, and Duke Energy has proposed investments in areas like battery storage and electric vehicle infrastructure.
Warren said the company is focusing its wind, solar and energy storage projects in markets where it doesn’t have a monopoly.
“But here,” he added, “the business model is reliant on building big power plants.”
Before the net-zero announcement, Duke Energy's latest plan for North Carolina showed coal falling from 12 percent of electricity generation next year to 3 percent in 2034, while generation using natural gas would go from 27 to 39 percent. Nuclear would still comprise about half, and renewable sources were to go from 5 to 8 percent.
“That’s not enough,” Carrboro Alderman Sammy Slade said of Duke Energy's previous renewable energy goal, during Friday’s climate strike at Peace and Justice Plaza. “If they plan to really be net-zero by 2050, then they need to be starting now. They can’t afford to continue with coal and natural gas.”
UNC gets electricity from both Duke Energy and an on-campus cogeneration plant that uses coal and natural gas.