Burning wood for electricity may be renewable, but it may not help the climate
Here's another example of a climate-change solution that may actually be the opposite. Wood pellets made from trees cut in the forests of North Carolina and the Southeast are a growing alternative fuel for power companies in Europe that want to be more climate friendly.
Growth in wood pellet exports from the United States to Europe has been driven by European policies that treat wood pellets as zero carbon, and by government subsidies on both sides of the Atlantic. But a new report says producing and burning wood pellets actually winds up being more polluting than coal, which it's replacing.
The report "Greenhouse gas emissions from burning US-sourced woody biomass" was released Thursday by think tanks Chatham House in the U.K. and Woodwell Climate Research Center in Massachusetts.
Incomplete accounting for carbon
The U.N.'s Intergovernmental Panel on Climate Change says biomass, which includes any kind of fuel from natural sources, can have benefits as part of carbon-reduction efforts. The "zero-carbon" argument is that since trees can be replanted, the new trees cancel out the loss of old trees.
The problem is that producing, delivering and burning all those wood pellets for energy is anything but carbon free. And that's not included in the "carbon accounting," at least as the Europeans are doing it.
For one, wood pellets emit 10% to 15% more CO₂ than coal. And the report's authors say that while EU regulations adopted in 2009 allow wood pellets to be classified as "zero-carbon," the calculations fail to include energy use in the wood pellet supply chain, the loss of trees that remove carbon dioxide from the atmosphere naturally (known as sequestration), and emissions from decaying trees left after harvesting.
Phil MacDonald of Ember, another British think tank, was asked to review the new report. He said Thursday it's time for Europe to move away from its assumptions that wood pellets are a clean industry.
"We're starting with the fact of the emissions coming out of the chimney, which we know are greater than coal … then working back from there (and) doing what this paper does, which is trying to look at all the foregone sequestration, look at the supply chain," MacDonald said. "And, as this paper has demonstrated, when you do that, you suddenly see the full scale of the emissions that are inherent in biomass."
The report says if you included the amount of carbon expended in production, that would add 22% to 27% to the UK's total greenhouse gas emissions from electricity generation. The Chatham House and Woodwell researchers say that's equivalent to adding 6 to 7 million passenger vehicles to the roads.
Industry in eastern North Carolina
This isn't just a distant story. Wood pellets are big business in the Carolinas.
On a recent two-days trip to tour southeastern North Carolina sites tied to the wood pellet industry, there were recently logged forests, community activists talking about the issue and two massive domes at the Port of Wilmington where a company called Enviva stores wood pellets awaiting shipment to Europe.
Andy Wood is director of the Coastal Plain Conservation Group, based in coastal Pender County, and said the wood pellet supply chain is bad for the climate. Echoing what's in Thursday's report, Wood said when you add up all the energy needed for harvesting, drying and processing, and transporting those wood pellets, the math just doesn't work.
On top of that, when you cut a tree, you're losing something that actually keeps carbon out of the atmosphere naturally, he said.
"The carbon footprint is enormous, which is why this does not work as a renewable source of energy," Wood said. "That is a contrived and fabricated claim that has been made, mostly by willfully ignorant politicians.
"We already have carbon capture and sequestration under way, for free, provided by nature, in the form of trees and other plants,” Wood continued. “They build tissue using carbon dioxide, so they're capturing our CO2, generated from our automobiles today, they're capturing that, storing it in wood, for the benefit of generations none of us will ever know."
A growing industry
Despite that, the wood pellet industry is growing in the U.S. Last year, U.S. producers exported 7.1 million metric tons of wood pellets to the European Union, worth almost $1.4 billion. That was up 5% from 2019.
It can be a good deal for landowners, who can harvest and sell trees to companies like Enviva.
To Charlie King, who owns land north of Fayetteville, selling Enviva the harvest of trees and scrap left from logging is extra income that pays for taxes and upkeep of his land.
"The service that they provide to people like me, as far as I know, cannot be found anywhere else," King said, as he led a tour of his land Tuesday.
Enviva operates four plants in North Carolina and one in South Carolina. And most of the plants are in rural communities where the jobs are welcome.
Government subsidies and tax breaks have helped wood pellets become a big business here and a growing part of the energy mix in Europe. Energy producers in Europe get incentives to mix wood pellets with coal in their power plants. And wood pellet producers in the U.S. get incentives to locate their plants here and create jobs — without regard for the environmental or climate impacts.
As WFAE has reported previously, the state of North Carolina has given wood pellet companies at least $7 million in incentives since 2014.
"We're burning time"
Still, environmentalists and residents also worry about air and water pollution from the wood pellet plants. And they worry about the loss of trees.
Kim Cesafsky, Enviva's director of sustainability, said they mostly use trees and waste wood that nobody wants — the "lowest grade material from a harvest."
"About 20% of what we're taking is what we call ‘sawmill residues,’” Cesafsky said. “So, this is sawdust, shavings from either lumber or furniture processing. I think about 14% is from thinnings. And then the remainder is what we call ‘primary wood.’ And so, it's usually coming from other types of kind of final rotation harvest, predominantly a clear cut, which is when all of the trees are removed from a property."
That remaining two-thirds includes whole trees, usually not large enough to be sold for lumber or other higher uses, Cesafsky said.
But Wood, of Coastal Plain Conservation Group, said those trees are performing a service to the planet, and will take decades to be replaced.
"We're burning time right now, by removing the one asset that is the most important tool we need, which is something to remove carbon dioxide from the atmosphere today, not in 10 years. Today," Wood said.
UPDATE: Enviva said in a statement Thursday night that it is "deeply disappointed to see Chatham House reach such flawed conclusions in the report." Enviva said the findings "are based on faulty inputs, incorrect assumptions and outdated arguments that have been repeatedly disproven by the world’s most renowned climate and forestry experts."
"It fails to recognize biomass’ important role in reducing the EU and UK’s reliance on coal and facilitating a swift transition from fossil fuels to renewable energy," Enviva said.