Wood pellets have become a popular fuel, but scientists are divided on whether burning wood to produce heat and power can be considered climate friendly.

Oregon Department of Forestry/Flickr (CC BY 2.0)

U.S. EPA says it will define wood as a ‘carbon-neutral’ fuel, reigniting debate

Weighing in on a fierce, long-standing climate debate, the head of the U.S. Environmental Protection Agency (EPA) in Washington, D.C., said yesterday the agency will now define wood as a “carbon-neutral” fuel for many regulatory purposes.

The “announcement grants America’s foresters much-needed certainty and clarity with respect to the carbon neutrality of forest biomass,” EPA Administrator Scott Pruitt said at an event in Cochran, Georgia, The Washington Post reports. But many environmental groups and energy experts decried the move, arguing the science is far from settled on whether wood is a climate-friendly fuel.

As Science contributing correspondent Warren Cornwall reported last year, the forest products industry has long been pushing for the carbon neutral definition in a bid to make wood an attractive fuel for generating electricity in nations trying to move away from fossil fuels. The idea is “attractively simple,” Cornwall reported:

The carbon released when trees are cut down and burned is taken up again when new trees grow in their place, limiting its impact on climate. …

Yet moves by governments around the world to designate wood as a carbon-neutral fuel—making it eligible for beneficial treatment under tax, trade, and environmental regulations—have spurred fierce debate. Critics argue that accounting for carbon recycling is far more complex than it seems. They say favoring wood could actually boost carbon emissions, not curb them, for many decades, and that wind and solar energy—emissions-free from the start—are a better bet for the climate. Some scientists also worry that policies promoting wood fuels could unleash a global logging boom that trashes forest biodiversity in the name of climate protection.

EPA’s Science Advisory Board has been studying the issue for years as part of the agency’s effort to decide how to account for greenhouse gas emissions from wood burning, and regulate wood-fired power plants. But the agency has been under persistent pressure from lawmakers in Congress and industry to give wood a climate-friendly label.

Yesterday, Pruitt said he intends to do just that by issuing new policy guidance. But it is not clear how quickly the guidance might have a real-world effect. Although Pruitt has said he plans to rewrite EPA’s clean air and power industry regulations, the agency has yet to specify what those new rules might look like, or exactly how they might treat the use of wood as fuel for power plants. And many of the rules have been tied up in long-running court battles that aren’t likely to be resolved anytime soon.