Environmental and green energy advocates are challenging Duke Energy's plans to burn wood in two of its coal-fired power plants, saying efforts to meet a new clean-energy standard could hurt the state's forests.
North Carolina's millions of acres of woods are expected to fuel much of the renewable energy the 2007 law mandates. But should power plants befueled by stumps, sawdust and old two-by-fours, or freshly cut trees?
Burning whole trees cut into chips, which Duke has tested at plants in Rowan County and South Carolina, would "declare open season" on the state's forests, the Southern Environmental Law Center said in a legal challenge last month.
Making trees off limits, however, would severely limit utilities' ability to make 12.5 percent of their electricity from renewable sources by 2021 as the law requires, an N.C. State University researcher says. Cutting trees for energy, he predicts, would not substantially increase logging.
The debate underscores the importance of working out the details of North Carolina's Renewable Energy and Energy Efficiency Portfolio Standard, the first to be adopted in the Southeast. With new energy sources comes the need for rules to police them.
State legislators, for example, are still debating how and where to allow commercial wind farms. Legislation stalled last year when members couldn't agree whether to allow turbines on mountain ridges.
The clean-energy law calls for utilities to use a variety of alternative fuels to make electricity, such as solar, wind, swine and poultry wastes and the large group of organic fuels called biomass. Biomass, it says, includes "wood waste."
Duke Energy says the wording is only an example of wood that utilities are allowed to burn.
Duke has asked the N.C. Utilities Commission for permission to burn wood with coal at its Buck power plant in Rowan County and its Lee plant in Williamston, S.C.
The utility says it doesn't know what form of wood it would use but wants to preserve the right to use whole trees, as it did during tests last year.
Excluding them, it wrote state environmental officials, "would severely limit the ability of our utilities and potential investors in biomass power production to use biomass resources."
The Southern Environmental Law Center and the Environmental Defense Fund favor a literal approach, insisting "waste" means logging, mill and construction scraps.
"Where the legislation says 'swine waste' and 'poultry waste,' it doesn't envision burning pigs and chickens," said Derb Carter, Carolinas director of the law center. "In the same sense, we don't think 'wood waste' should be considered whole trees."