Two very different views of biomass were presented to the public last week. On one hand, Maine’s senators cited looming regulations on biomass burning as the reason for their support of an unsuccessful resolution to strip the U.S. Environmental Protection Agency of its authority to regulate carbon dioxide emissions. The same day, the state of Massachusetts issued a report that found that burning biomass to create electricity was no better, in terms of emissions, than using fossil fuels.
These conflicting positions show that calculating the “greenness” of biomass is a complicated task, which neither the EPA nor the biomass industry has finished.
Sens. Susan Collins and Olympia Snowe blasted the EPA for a recent finding that burning biomass is not carbon-neutral. Such a finding, the senators said, would result in job losses at more than a dozen facilities that burn biomass, either to produce electricity for sale or use in their facilities.
Scientifically, of course, the EPA is right. When wood is burned, carbon is released into the atmosphere. This is only part of the picture, however.
If the wood debris — usually tops and branches — were left in the forest, it would emit carbon dioxide and methane as it decomposed. Second, trees, which absorb carbon dioxide, grow back much more quickly than decomposing organisms turn into oil. So, the carbon payback period is much shorter for biomass than it is for fossil fuels.
Rather than arguing with the fact that burning biomass emits carbon, regulators and lawmakers must find an appropriate way to offset biomass carbon emissions with the payback period. This is especially important if, as the president has pushed for, Congress passes legislation that puts a price on carbon emissions. Clearly carbon emissions from biomass-fueled plants shouldn’t be treated the same as those from coal- or oil-fired plants. At the same time, however, biomass shouldn’t be given a pass.
According to the report, burning biomass rather than oil to produce heat will result in carbon emissions savings in as little as five years. Using the wood debris rather than fossil fuels to produce electricity could result in increased emissions, it found.
The study was done by the Manomet Center for Conservation Sciences for the Massachusetts Department of Energy Resources as part of the department’s assessment of the state’s renewable portfolio standards, which are aimed at reducing greenhouse gas emissions.
Concerns were also raised that incentives aimed at biomass energy could cause an increase in tree harvesting, which would also increase carbon emissions.
This can be remedied by ensuring such incentives apply only to wood waste, which is currently the case.
The report does not mean that further investments in biomass aren’t warranted, but rather that further study is needed to better quantify the environmental, economic and security (biomass is homegrown; oil increasingly is not) benefits of using wood debris for fuel.