Green energy or greenwashing? The wood pellet industry is the target of fierce debate
Ahead of a major UN Climate Conference in Glasgow, activists in North Carolina are trying to draw attention to a kind of renewable energy that they say isn’t so green.
On a sunny Saturday morning on the Cape Fear River, dozens of climate activists climbed on board the Henrietta to shout down a business that works out of the Port of Wilmington.
The targets of their ire were two bulbous, inflated storage containers, filled to the brim with dried wood pellets.
Derb Carter, founder of the Southern Environmental Law Center, said the wood from that material comes from North Carolina forests: “Here in North Carolina, the biomass industry is harvesting to create wood pellets that are all for export.”
Wood pellets are made of dried and compressed wood fiber. They’re lightweight, pill-sized bits of wood that are burned by the ton to generate electricity.
Wilmington is one of six ports that wood pellet company Enviva uses to ship internationally. Enviva is the largest wood pellet company in the US, with $684-million in revenue in 2019. According to Enviva’sinvestor presentation from May 2021, demand for wood pellets has more than doubled since 2012, as power plants around the globe phase out coal in favor of the subsidized biofuel. Emissions for the cut trees aren’t counted in the countries where they’re burned, so those countries can write the energy off as carbon neutral.
Carter said the wood pellet industry is destroying North Carolina forests in the name of green energy in other countries.
“So you have a steady flow of ships that come in, where the wood pellets are offloaded onto the ship and start their journey across the Atlantic Ocean, burning a lot of carbon on the way, to then get those wood pellets all the way across the Atlantic Ocean to then burn," he said.
Enviva has a goal of net-zero emissions by 2030 in its own operations, and says more trees are planted than cut each year in the southeastern US- thus making the fuel carbon neutral. The company also suggests its fuel is environmentally friendly because it directly replaces fossil fuels.
But activists say the real carbon emissions are just lost in bureaucracy.
Advocacy groups like the Natural Resources Defense Council (NRDC) have criticized the Sustainable Biomass Program (SBP), which gives sustainability certification to wood pellets — including Enviva's. NRDC says companies like Enviva rely on SBP as "an industry-dominated certification scheme to 'greenwash' their practices as environmentally friendly." The Dogwood Alliance, which has long opposed the wood pellet industry, refers to Enviva's sustainability policy as 'greenwashing.'
Enviva disputes these claims. The debate comes down, in large part, to how carbon gets counted.
The accounting method is a strange loophole in existing international climate agreements, like the Kyoto protocol and the Paris accord, created in an attempt to prevent the double-counting of carbon. Essentially, carbon is supposed to be counted when trees are cut down, not when they’re burned.
“So we've created this kind of false accounting for the UK," Carter explained. "When it reports its carbon emissions, it only looks at the point of combustion. And under European policy, the amount of carbon from biomass is zero.”
A recent study from the British think tank Chatham House found that wood pellet burning in the UK accounted for 13 to 16 million tons of CO2 emissions in 2019. That’s accounting for combustion, shipping, and carbon emitted in the supply chain. And it includes the carbon that would have been sequestered —pulled out of the air and stored — by the trees had they not been cut down.
If all these carbon sources had been officially counted that year, it would have added 22 to 27 percent to the industry’s emissions — far higher than traditional accounting estimates.
Enviva’s director of sustainability, Kim Cesafsky, called that count inaccurate because it differs from the accounting structure used by the Intergovernmental Panel on Climate Change. The IPCC’s accounting measures emissions over the course of a century instead, because carbon emitted today will be pulled back into a tree through photosynthesis sometime in the next hundred years.
“When you look at biomass energy, you need to look at the lifecycle emissions," she said. "When you burn coal, it's a one-way street.”
Enviva points to a market-driven model which found biomass emits 74% to 85% less carbon than coal. That number is based on the assumption that landowners will be more inclined to plant trees if they can be sold for a profit later, which means landowners who aren’t currently foresters may start planting trees for later harvest.
That same paper also assumes 36% of the biomass used for production of wood pellets would come from sawmill residues by 2032— a relevant statistic because those residues would break down and emit carbon anyway, and don't require any new trees to be cut down. Instead of the 36% assumed in the model, sawmill residues make up just 18% of Enviva's current mix.
With the current method of carbon accounting, European emissions from European energy plants are essentially exported to the country which chopped the trees. It’s a tidy way for Europe to keep its hands clean — and European countries pay a lot of money in subsidies to do so.
Carbon neutral, eventually?
The argument is that the trees are replaced and regrown, so the biofuel comes out close to neutral over the course of decades or centuries.
But William Schlesinger, former president of the Cary Institute of Ecosystem Studies, says the planet doesn’t have that long, considering the emergency of climate change. “The overwhelming problem with wood pellets is that you when you burn them, you put a lot of carbon in the atmosphere instantaneously," he says. "It takes decades to a century to recapture that. And that's the biggest net negative of wood pellets in terms of an energy source.”
More than 80% of Enviva’s wood is sourced from entire trees, and sometimes entire forests. Often, the tracts of forest they buy the rights to have been left untouched by the families who own them- leaving plenty of gnarled trees unfit for the sawmill. Enviva calls this material “low-quality wood,” but Schlesinger says that’s a purely economic way of thinking about it.
“That statement really reflects a forestry bias, I would say that you're anticipating the trees is having dollar value, and that you're going to capture that at some time by cutting," he said.
Sawmills want straight and tall trees for the sake of profit, but Schlesinger says unmanaged, gnarled forests do plenty of good for society through of biodiversity and carbon sequestration. He suggests that paying forest owners to keep their trees alive would be a better method for limiting carbon reductions, rather than chopping the trees down to burn.
Enviva considers that close to carbon-neutral, however, because over the lifetime of the newly planted tree, much of that carbon will be pulled back out of the atmosphere.
“It's very simple forest economics, says Enviva's Director of Sustainability, Kim Cesafsky. When foresters replant trees at a faster rate than they're cut down due to the economic incentives, "there are no net emissions to the atmosphere. That is not the case with fossil fuels, which is what our product is displacing directly.”
Still, Schlesinger says the wood pellet industry is a carbon loss on both ends. First, because the adult trees will no longer sequester carbon, and second, because all the carbon the tree has ever pulled out of the air is released at the moment it's burned.
2 to 2.5% of Southeastern forests are cut each year for the timber industry. Wood pellets make up only 3% of the timber industry in the southeast, but Schlesinger says that sector is actually the worst for climate change out of the rest of the timber industry, because the trees are cut down only to be burned.
“You build a wood house or wood furniture, wood office building, that sequesters carbon," Schlesinger said." What used to be in the trees is now in the saw timber in the building, and will persist there as long as that building persists.”
All those southern trees are going to markets abroad for consumption. That’s why Derb Carter felt the need to draw attention to this issue with the river tour ahead of the UN’s climate change conference in Glasgow, which starts Oct. 31. With the United Kingdom hosting the conference, it’s a great time to bring up their specific subsidies.
The UK is Europe’s largest market for wood pellets, with four power plants that have been converted to wood from coal. Each burns 2.3 million metric tons of wood pellets each year, according to the USDA. The Drax power station, just one of those four, received $1.1 billion in subsidies last year for burning biomass instead of coal.
Critics of biomass also note that Drax, along with other energy companies, helped found the Sustainable Biomass Program that certifies wood pellets as sustainable.
“We're going to continue to try to stop the expansion and ensure there's no renewal of contracts," Carter said. "If we cut off the demand for this, and we cut off the government subsidies, it will stop as soon as it started. Because it makes no economic sense, it makes no climate policy sense."
The UK’s current set of wood pellet subsidies are set to expire soon, and it’s unclear whether they’ll be continued. It is easier for a country to meet its climate goals and promises if burning wood pellets counts as carbon neutral, after all. But activists hope to end the subsidies that keep the industry afloat, and see investments in wind and solar instead. That, they say, would be a real investment in slowing down climate change.