Biomass: The Darling of Renewables in TN – But It's Not All Pretty
NASHVILLE, Tenn. - Biomass has become the darling of the renewable-energy world in Tennessee and throughout the Southeast, and a new study takes a close look at the good and bad.
Biomass refers to burning wood-production leftovers to generate electricity, compressing them into fuel pellets, and wood- ethanol production. The latter is the focus in Tennessee.
David Carr, senior attorney at the Southern Environmental Law Center, says this study shows that even renewable-energy sources also can be carbon-pollution sources.
"This new study shows that EPA and other policymakers cannot assume that biomass energy has no effect on CO2 levels in the atmosphere."
The study finds a spike in pollution during at least the first 35 years of biomass production, and recommends state and federal policies which encourage efficient technologies to reduce the load. The federal Environmental Protection Agency also is studying biomass carbon emissions.
Robert Perschel, eastern forests director at the Forest Guild, cites other considerations as well, including how removing woody debris from forests affects soil health, water quality and wildlife, as well as the short- and long-term pollution picture.
"We can use biomass for 35 to 50 years to produce electricity. We'll have less carbon in the atmosphere than if we had used fossil fuels. If we use biomass for more than 50 years, we'll have less carbon than when we started."
The carbon picture could become more complicated as the biomass industry grows, Perschel says. If more live trees are cut for production, that means fewer trees in forests to naturally absorb carbon in the atmosphere.
The study, "Biomass Supply and Carbon Accounting for Southeastern Forests," was conducted by the Biomass Energy Resource Center, Forest Guild and Spatial Informatics Group on behalf of the National Wildlife Federation and Southern Environmental Law Center, and is online at biomasscenter.org.