Maryville College's Good Wood
Jim Renfro, local air quality specialist for the National Park Service, also agrees that burning wood is cleaner than burning oil or gas: It doesn't emit the dangerous nitrogen oxide and sulfate pollutants. "But the amount of volatile organic compounds (VOCs) emitted should be pretty high; lots of organics (carbon) are emitted with burning wood," he says. (VOCs occur naturally in heavily forested areas, and in the southeast, the level of VOCs is naturally high due to the amount of trees and foliage of the area.)
The wood that is used is ground up into chips, not dust. McCall says dust is too fine and often too wet for use. Also, the wood is remnants from mostly lumber. "We tried burning the city's brush, but it was too green and stringy," he says.
If burning wood for a heat source is efficient and semi-environmentally friendly, then why aren't more colleges, universities and industries using it? McCall says that there just isn't enough wood waste to meet that large of a demand. He says that in Maryville, the college and one factory are the only two places that utilize wood waste as a heating source.
Even with only two places using wood waste in Maryville, competition could potentially cause supply problems. If a factory bought out the contract for wood, the college could be cut off, says McCall. He explains that at one time the college did have to buy wood waste from North Carolina when local supplies were low.
Still, there aren't many drawbacks to burning wood for energy besides the labor and the slowness of dumping the wood into the furnace.