By Ashley Mooney

As researchers look for alternative fuel sources, researcher Christopher Galik of the Nicholas Institute for Environmental Policy Solutions finds that any discussion of biomass has to include market forces.

Galik and fellow scientist Robert Abt wanted to eliminate the differences between studies on the feasibility of biomass to compare them evenly. Theyidentified which variables caused both positive and negative conclusions in earlier studies and  found that accounting for market forces changes the estimated greenhouse gas emissions of biomass.

“One of the things that is often mentioned with regard to biomass—specifically when you’re talking about greenhouse gas emissions—is whether or not it’s better or worse than a fossil fuel alternative,” Galik said. “Does using biomass help bring down greenhouse gas emissions or bring it up? There have been a number of studies that said both.”

A biomass-fired power plant in Italy. (Photo by Threecharlie via Wikimedia Commons)

The term biomass can include agricultural residues or leftovers from the processing of wood products—such as scraps or other mill residues. Galik, however, uses a more narrow definition in his study: forest-based material, referred to as woody biomass, which includes trees and parts left over after harvest.

“When you include market responses, you actually see a larger greenhouse gas benefit than if you didn’t,” Galik said. “If you assume you go into a forest and cut down more wood that could be used for energy, but you didn’t account for other market effects—such as how it will affect prices —then you have a negative greenhouse gas effect.”

In studying market effects, the researchers examined the viability of biomass as an alternative renewable energy source specifically in the southeast, a region well known for its forest resources. Galik said wood’s abundance and readily available data and expertise on  forests in the region made it ideal for study.

Galik compared biomass emissions to that of coal, which has a relatively stable amount of emissions per unit. The issue with forest biomass, he said, it that trees can either stand on the landscape sequestering carbon or burn as fuel, so the net greenhouse gas emissions depend on how much there is of one versus the other.

“When you create a market for biomass, you can provide the incentives for landowners to plant more acres and manage their forests more intensely, storing more carbon than you would have otherwise…. This on balance brings down total greenhouse gas emissions from bioenergy.”

With varied evidence regarding biomass’ viability as a fuel source, the U.S. EPA Science Advisory Board is investigating how to measure the carbon debt of biomass, according to a Climate Wire  article. The agency is trying to create environmental policy and quell some of the controversy.