WASHINGTON, D.C. – Using biomass and wood pellets for energy production may be far costlier for public health and air pollution than previously thought, according to newly published, peer-reviewed research. The use of biomass for energy has sometimes been cited as a renewable or clean energy alternative to fossil fuels. However, researchers at the University of North Carolina at Chapel Hill and the National Wildlife Federation found that unit for unit, biomass and wood pellet production may have worse impacts on air pollution than the fossil fuels they seek to replace.  

According to the new research, energy facilities that burn biomass release on average up to 2.8 times the amount of pollutants of energy facilities that burn fossil fuels in the United States, per unit of energy generated. The study also inventoried emissions from wood production facilities and found that they emit thousands of tons of pollutants — including health-harming toxics and particulates — every year.

“Fourteen million people in the United States live within a few miles of bioenergy facilities and breathe potentially harmful toxins and pollutants. As the bioenergy market continues to grow globally, it is critical that we understand the impacts and costs of utilizing biomass for energy, ” said Edie Juno, co-author of the paper and a forestry specialist with the National Wildlife Federation. “Given that these facilities are disproportionately located in Black, low-income, and other frontline communities, simply replacing one dangerous fuel source for another, even-more polluting source, is incompatible with our clean energy and just transition goals. It is clear from our research that bioenergy poses public health and environmental drawbacks and further research is needed before states and policymakers invest further in this technology.” 

“For too long, the impacts of bioenergy and wood pellet production on air pollution have been under-researched,” said Sarav Arunachalam, deputy director of the Institute for the Environment at the University of North Carolina at Chapel Hill and senior author of the study. "Accurately quantifying air pollutant emissions from the bioenergy sector is the first step before we can understand their subsequent air quality and human health impacts. Even though the absolute magnitude of emissions from this sector with growing activity is lower than those of non-bioenergy, the bioenergy sector emits more pollutants per unit energy generated than from non-bioenergy sources and this makes the new study all the more important."

The researchers found that facilities using biomass for energy generation contribute between 3-17% of the total emissions of criteria pollutants associated with electricity generation. Excluding the dirtiest fuels, biomass-to-electricity facilities still contribute 2-6% of the sector’s emissions, despite accounting for only about 1% of total capacity. An inventory of emissions from wood pellet production also found more than 55 hazardous air pollutants, along with more than 10,000 tons of volatile organic compounds (or VOCs) and more than 14,000 tons of particulate matter in annual emissions. 

The study points out that emissions estimates from wood pellet production facilities in current regulatory versions could be underestimated by a factor of two. Moreover, several large-scale wood pellet production facilities have also violated their air quality permit limits, putting nearby residents at greater risk.