BUCKSPORT, Maine — Contractors are working diligently to get an upgraded biomass system finished by the end of the month at Verso Paper’s mill in Bucksport.
The $42 million project includes refitting the No. 8 boiler to burn only natural wood products and the installation of a new 25-megawatt turbine. It’s part of Verso’s 2009 diversification strategy to establish energy production as a crucial part of the company’s portfolio.
When the upgraded biomass system is commercialized, the Bucksport mill could feed as much as 165 megawatts to the regional power grid, creating a new revenue stream for Verso, which reported a loss in adjusted net income of $39 million in the first quarter of 2012.
Verso spokesman Bill Cohen said the system could be complete by Nov. 1. The company used to feed the boiler natural gas, oil, coal and tire-derived fuel. Now, the boiler will run on biomass only, save for a small amount of natural gas used to ignite the boiler’s startup.
That means a reduction of 90 percent of fossil fuel use at the boiler, according to Verso, and the reduction of about 270 tons of carbon dioxide production every day. Another boiler at Verso will continue to burn natural gas, but the upgrade means the elimination of coal, oil and tire-derived fuel burning in Bucksport.
“It’s local, Maine, green, renewable power,” he said during a tour of the facility Thursday.
Work on the project began in November 2010, with the construction of a second woodlot, where biomass — sawdust, wood chips, tree bark and other wood-based harvesting and papermaking byproducts — is unloaded into piles before being fed into a hopper with a bulldozer.
Cohen said the upgraded boiler will consume triple the biomass it burned before, an increase the company claims will create more than 50 new jobs in the harvesting sector.
From the woodlot, the biomass is fed into the eight-story No. 8 boiler, where it is incinerated. Here, a crucial upgrade to inject fine-grain biomass high up in the boiler means more biomass consumed and more heat generated.
That heat hits a new 25-megawatt steam turbine. Some of the steam is diverted to the mill for the papermaking process. The rest hits a generator to create electricity for the regional power grid.
Verso is promoting the upgraded system as a victory for renewable, green energy. But there’s one claim that’s up for debate.
Cohen claims the biomass endeavor is “carbon-neutral,” meaning it doesn’t contribute the greenhouse gas to the atmosphere.
The argument for biomass’ carbon neutrality goes like this: Burning biomass releases only the carbon that was extracted from the atmosphere while the plants were alive. New growth (the pulp and paper industry claims every tree harvested is replaced naturally or by humans) consumes that emitted carbon, leaving the net pollution at zero.
But environmental groups claim that argument is bunk. They say that releasing the entire carbon load of biomass all at once through burning is drastically different than that carbon being released slowly as a plant naturally decays. Plus, it takes decades for a tree to grow enough to replace the carbon-sinking effect of a mature, harvested tree.
In 2009, the state of Massachusetts commissioned a study that found biomass releases more carbon into the air than either oil or coal, and may contribute to the overall level of greenhouse gas emissions.
Cohen said Verso is aware of the Massachusetts study, but that the company’s environmental consultants disagree with its findings.
“Or consultants disagree with that study. There is not general agreement among all the environmental groups, but so far the advantages outweigh the disadvantages,” he said. “It’s something we’ll continue to look at.”
Either way, work on the system continues. The boiler is up and running, but the steam there is not yet diverted to the turbine. Cohen said that now, nearly two years since construction began, the end is in sight.
“We hope within the next few weeks to get the bugs worked out, and by the end of the month to be commercialized,” he said.
Follow Mario Moretto on Twitter at @riocarmine.