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The Wood Pellet Business is Booming. Scientists Say That’s Not Good for the Climate.

2024-12-19 08:14:11 reviews

In rural Southern towns from Virginia to Texas, mill workers are churning out wood pellets from nearby forests as fast as European power plants, thousands of miles away, can burn them.

On this side of the Atlantic, new pellet plants are being proposed in South Carolina, Arkansas and other southern states. And Southern coastal shipping ports are expanding along with the pellet industry, vying to increase deliveries to Asia.

While the United States has fallen into a coronavirus-induced recession that dealt a blow to oil, gas, and petrochemical companies, for biomass production across the South, it’s still boom time. 

The industry has exploded, driven largely by European climate policies and subsidies that reward burning wood, even as an increasing number of scientists call out what they see as a dangerous carbon accounting loophole that threatens the 2050 goals of the Paris climate agreement.

This month, the Environmental Protection Agency, acting at the direction of the U.S. Congress, is expected to propose securing that loophole with a new rule that details how burning biomass from forests can be considered carbon neutral, at least in the United States.

The industry wants to see regulations that will keep their businesses growing, including expanding U.S. energy markets that now barely exist. But some scientists and environmental groups argue that new EPA rules that are favorable to the industry would put the climate at further risk, along with forest ecosystems across biologically rich landscapes.

“Burning wood puts more carbon dioxide in the air right now, today, with certainty, than the fossil fuels you were burning,” said John Sterman, a professor of management and engineering at the Massachusetts Institute of Technology, who has published peer-reviewed research on lifecycle carbon emissions from burning wood pellets. 

To solve the climate crisis, he said, “emissions from fossil fuels need to go down rapidly, but it is equally important to keep the carbon in forests on the land.”.

For their part, the industry leaders believe they have science on their side, making a case that wood pellet production is barely putting a dent in the carbon-storage capacity of forests in the South.

The industry wants EPA rules that “recognize the benefits of bioenergy,” and that provide certainty, said Paul Noe, vice president of public policy for the American Forest & Paper Association, a lobbying group for the paper and wood products industry. “Is it recognized as being beneficial, or is it, as some say, worse than burning coal? You have to know where you stand,” he said. “We have been waiting for an answer for a decade.”

An Argument Over Forests and Trees

The idea that trees are a renewable resource and burning them is carbon neutral was written into the Kyoto Protocol, the 1997 international agreement to fight global warming.

It’s supposed to work like this: Burning wood in power plants releases carbon dioxide into the atmosphere, but newly planted trees in the forests soak up an equivalent amount of carbon through photosynthesis, which gives trees the energy they need to grow, while releasing oxygen.

The dispute revolves around how quickly that happens, given an increasing sense of urgency over the speed with which global carbon dioxide emissions must be reduced to avoid the worst effects of global warming.

In 2018 the United Nations’ Intergovernmental Panel on Climate Change released a report describing what it would take to keep global temperatures from rising more than 1.5 degrees Celsius, the most challenging benchmark of the 2015 Paris Agreement. To reach that goal, carbon emissions would need to start dropping “well before 2030,” and be on a path to fall by about 45 percent by that same year, now just a decade away.

Wood pellets used for heating. Credit: Unkel/ullstein bild via Getty Images

Two years ago, almost 800 scientists wrote to the European Parliament, arguing that “cutting down trees for bioenergy releases carbon that would otherwise stay locked up in forests, and diverting wood otherwise used for wood products will cause more cutting elsewhere to replace them.”

They added, “Even if forests are allowed to regrow, using wood deliberately harvested for burning will increase carbon in the atmosphere and warming for decades to centuries—as many studies have shown—even when wood replaces coal, oil or natural gas.”

Given enough time, forests may pull enough carbon dioxide out of the air to make up for the electricity generation, Sterman acknowledged. But that’s not guaranteed; the forests also could be lost to development. And by removing trees now, he said, the industry is “taking trees that would have grown and taken even more carbon out of the air.”

In the meantime, he said, “you have made climate change worse. The sea level will be higher. There will be more extreme weather and more ocean acidification.”

Other people argue that the scientists are not seeing the forests for the trees—literally.

At least in the highly productive Southern forests of the United States, there is no carbon debt to worry about, say industry representatives and a former top U.S.Department of Agriculture official in the Obama administration.

“If you do the analysis at the [timber] stand level, and that one little patch of trees, you are going to lose the carbon and have to wait,” said Jennifer Jenkins, vice president, and chief sustainability officer at Enviva, the world’s largest producer of wood pellets, with extensive operations in the South. “But forests are managed at the landscape scale.”

Only 2 percent of the forests in the South are harvested every year, leaving 98 percent in various stages of regrowth, more than enough to soak up what gets burned to produce electricity, she said. 

Robert Bonnie, who was an assistant secretary of the USDA during the Obama administration and oversaw the U.S. Forest Service, makes a similar argument, though he said he prefers the term “carbon beneficial” to “carbon neutral.”

Decades of Forest Service data collection show that southern forests are growing so fast that they are sequestering a massive amount of carbon, even as they are being harvested for wood products, said Bonnie, who is now an executive in residence at Duke University’s Nicholas Institute for Environmental Policy Solutions.

A key point, he said, is that Southern forests are primarily privately  owned, and the best way to make sure they remain forests is for landowners to make money off them as forests.

“We have had timber markets in the South for a long time,” he said. “Has the forest gone up or down? It’s gone up dramatically. So the notion that somehow markets in and of themselves are going to drive down forests’ carbon is really belied by decades of experience in the South.”

House Democrats’ newly released plan to deal with the climate crisis acknowledges the scientists’ concerns and calls for more research to better understand the carbon implications of using biomass energy and for safeguards to make sure harvesting methods do “not contribute to the biodiversity crisis.” The plan also calls for research into capturing carbon emissions from biomass energy plants.

An Exploding Industry

Across the South, environmental advocates have been alarmed at the growth of wood pellet production and exports.

Pellet exports have more than tripled, from 1.9 million metric tons in 2012 to about 6.9 million metric tons in 2019, and the first five months of 2020 outpaced the first five months of last year, according to Forisk Consulting, which analyzes the industry. Virtually all,  99 percent, of those exports in at least the last four years have come from the South, the company said.

The Southern Environmental Law Center closely tracks the industry, as well, and counts 22 pellet mills operated by nine companies, from Franklin, Virginia, to Woodville, Texas; They include mills owned by Enviva and by the Drax Group, with its massive wood pellet-fueled plant in England; 10 proposed mills where companies have filed for various environmental permits; and five other potential mill sites.

Enviva says it uses only low-value trees for fuel, or uses just branches and limbs that might otherwise be considered waste. 

But the law center and its partners, like the Dogwood Alliance and the Natural Resources Defense Council, have issued reports with photographs that they say show destructive logging practices and the conversion of whole trees to wood pellets. They include a 2018 report that concluded mature trees that had been locking up carbon for decades or more were being logged.

Poor, rural communities in North Carolina and other states are being put at risk from air pollution from pellet plants and flooding from logged landscapes, the law center and its partners argue. And much of the logging occurs within a coastal plain designated as a biodiversity hotspot by the Critical Ecosystem Partnership Fund, an international partnership that includes the World Bank.

The law center is worried that a new EPA rule will bake in the concept that burning wood for energy is carbon neutral. That could open up southern forests to even more clearcutting and result in the release of even more carbon emissions, said Scott Smallwood, a spokesman for the center.

With an increasing number of businesses and states looking to meet the Paris goals, the new EPA rule could make it so that “any facility that will burn biomass can count those CO2 emissions as zero,” said Heather Hillaker, an attorney with the law center.

Keep it Simple

Former EPA Administrator Scott Pruitt set EPA on its track to adopt a new biomass rule in 2018, at an event with forestry industry leaders in Georgia. A proposed rule went to the Office of Management and Budget for review earlier this year.

But Mary Booth, the director of the Partnership for Policy Integrity, a research organization and a principal critic of the biomass industry, said that whatever the EPA does, it won’t be all the agency’s doing.

The biomass industry has friends in Congress, Republicans and Democrats alike, she said. And in announcing his intention for the EPA to develop a biomass rule, Booth said, it was significant that Pruitt cited the direction Congress gave the EPA in a 2018 appropriations bill. According to that guidance, federal agencies including the EPA were to establish policies that “reflect the carbon-neutrality of forest bioenergy and recognize biomass as a renewable energy source, provided the use of forest biomass for energy production does not cause conversion of forests to non-forest use.”

Political leaders in Minnesota, including former Democratic presidential candidate Sen. Amy Klobuchar, and in northeast states like Maine and New Hampshire, where the wood biomass industry has struggled, have rallied behind the biomass industry.

An EPA spokeswoman would not say when the proposed rule would be made public. But the agency has been wrestling with how to regulate biomass energy for years.

“There were groups that were adamant that biomass should be treated as carbon neutral for regulatory purposes, yet that sort of defied the science,” said Janet McCabe, a former top EPA air quality official in the Obama administration who now teaches law at Indiana University. “There were other groups that were equally adamant that was only not only incorrect as a matter of science but would lead to a really dangerous climate policy.”

EPA convened a panel “to create scientific clarity,” but the panel did not conclude its work before the administration left, she said.

McCabe and others said they don’t know what EPA might propose.

But it will probably have to address how companies track carbon from forest to atmosphere and back to the forest, and also forest sustainability.

Noe, the American Forest and Paper Association vice president, said the EPA should avoid anything complicated. “You do not have to create an elaborate carbon accounting scheme based on these models that are trying to predict the future,” he said. “They are extremely opaque and will put a chill on the U.S. bioenergy economy.”

Instead, he said, the rules could call for tracking forest carbon over time.

Bonnie, the former USDA official, said that as inclined as he is to support burning wood from commercial forests as part of a climate solution, he has little faith that the Trump administration, based on its track record, will create a rule with climate or the environment top of mind.

“We should have good (carbon) accounting, and people should have faith in that accounting,” Bonnie said. “People lose faith when we can account for this stuff properly, and I worry about people losing confidence.”

 

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