BRATTLEBORO -- Would burning wood on a large scale to produce electricity be a boon or a bane?
It depends on who you talk to.
On one side of the divide, proponents of biomass plants point to reducing our reliance on fossil fuels, taking advantage of a local fuel source, creating new jobs and reinvigorating the forest industries.
Those who oppose the burning of wood point to its low efficiency, air pollution, the exploitation of our forests for short-term gain.
"Big biomass plants are horrible," said Chris Matera, the founder of Massachusetts Forest Watch, which opposes a wood-to-electricity power plant in Greenfield, Mass. "They use massive amounts of wood to produce a small amount of electricity."
Burning wood for electricity is only 25 percent efficient.
Matera also believes that district heating systems, such as the one Brattleboro Thermal Utility is exploring, is not a solution to the country's energy needs, especially when it comes to global climate change.
The claim that burning wood is "carbon neutral" is "total nonsense," said Matera.
"Burning wood takes a few minutes but it can take 50 to 100 years for a tree to come back," he said.
Thus, burning wood adds carbon dioxide to the atmosphere faster than it can be reabsorbed.
But Adam Sherman, the program director of the Biomass Energy Resource Center in Montpelier said district heating systems and large-scale biomass-to-electricity projects shouldn't be lumped together.
"A big inefficient power plant -- that's scary," said Sherman.
While a 50-megawatt power plant, such as the one proposed for Greenfield, needs at least 500,000 tons of wood a year, a small thermal utility, such as the one proposed for Brattleboro, would use 12,000 to 16,000 tons a year.
District heating systems are "a very appropriate use of local forest resources at a much higher efficiency at a scale that is much more appropriate to certain communities," said Sherman.
In Vermont, 42 schools are heating with wood chips, including Brattleboro Union High School. Other locations include the Vermont State House and state offices, the government complex in Waterbury, the hospital in Newport and Middlebury College.
"In Vermont we have created a track record and a path forward on how we can utilize our precious forest resources," said Sherman.
But, added Sherman, any project needs to move forward "with the utmost care, scrutiny and due diligence on sustainability, availability and the reliability of the resource base. The amount of wood that can be sustainable is a very finite amount."
While Sherman and Matera disagree on some points, they both agree that burning wood for electric power generation is not sustainable.
Large-scale biomass plants would leave nothing for cordwood, pellets or woodchips, said Sherman.
"You've exhausted every single drop of sustainability at no more than 25-percent efficiency," he said. "But to say any kind of biomass use would trigger massive change is absurd."
According to a wood fuel study conducted by BERC, said Sherman, conservative estimates reveal there is up to 1 million tons of wood above and beyond the current yield that could be burned.
When burning biomass for any use, whether electric generation or heating and hot water, what really needs to be taken into account is the full cost of the impact on the environment, said James "Jae" Edmonds, the chief scientist for Pacific Northwest National Laboratory's Global Change Research Institute on the campus of the University of Maryland.
"Whether it's fossil fuels or chopping down the forest, carbon is carbon to the atmosphere," he said.
Biomass as a carbon-neutral fuel source is relative to land use practices, said Edmonds.
"You might actually have far greater emissions," he said. "That's because the carbon tied up in forests, in the soil and in grasses is ‘huge.'"
But if forests are replaced faster than wood is burned, said Edmonds, carbon entering into the atmosphere is removed simultaneously.
"We consider that a wash," he said.
But Edmonds added a caveat: To do so would mean converting land into forest production with consequences that aren't always fitted into the calculation.
"We've got all this land to grow crops to feed people and the other things we use land for," said Edmonds. "If you want to grow biomass too, something's got to give."
Converting land to biomass productions can also drive up the costs of food crops, said Edmonds.
One way the food-crop issue can be confronted, said Edmonds, is if we reduce our consumption of meat. Feed that goes to animals could instead be used to feed humans without increasing the amount of land under cultivation.
"It shifts the diet, frees up the land and makes space for bio-energy," he said.
If adequate planning is brought to the table, said Edmonds, biomass plants can contribute to reducing carbon in the atmosphere if everything from wise-use land practices and modern pollution-control technology is utilized, he said.
"Biomass can be really important in achieving low-carbon stabilization scenarios," said Edmonds. "It's a wonderful renewable. It can be better than any other renewable by a factor of two."
What we need is to put a price on carbon, said Edmonds.
Fossil fuels are relatively cheap because their impact on the atmosphere is not figured into their costs. Because of that, biofuels can't compete with fossil fuels on a cost-benefit ratio.
But if the full carbon impact was taken into account, the price of fossil fuels would rise to a more appropriate level reflecting their total impact on the environment.
All three men said it's important to produce power through a mix of different technologies, including fossil fuels with carbon dioxide capture, bio-energy, solar, wind and nuclear.
"All these things tend to work together or the whole system falls apart," said Edmonds.
"Biomass is not a silver bullet," said Sherman. "It's a piece of silver buckshot."
Conservation and efficiencies can go a long way to reducing our power consumption and precluding the need for additional power plants, said both Sherman and Matera.
Conservation and efficiency are not "chic or sexy," said Matera, but "The amount of energy we can reduce is monstrously more that the amount we can produce by burning wood."
Efficiency and conservation measures can reduce power usage by up to 50 percent.
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