MIDDLEBURY-Middlebury College recently opened a $12 million "green" biomass gasification power plant. According to college officials, the plant will provide the campus with both heat and electricity; it will use established power generation technology adapted to new, bio-organic fuel sources.
The main drive behind the plant's construction is a campuswide effort to reduce the institution's "carbon footprint" on the environment. It is hoped that the move will reduce local effects of "global warming".
Aside from the cost of construction, what will be the long-term costs of operating the new power plant? Despite the green claims made by officials and local supporters, could the project have a negative impact on the local environment? A local alternative energy critic thinks so.
According to a recent college news release, the plant's new biomass boiler is expected to reduce the use of No. 6 heating oil on campus from 2 million gallons to 1 million gallons annually. Campus officials also noted that the plant will reduce the college's carbon dioxide emissions by 40 percent or 12,500 metric tons of the greenhouse gas.
According to J. Kirk Edwards of Ferrisburgh, Vt., a community activist and a critic of what he terms "feel good, costly alternative power projects", claims the college left out details about the plant.
"This project has been oversold," he said.
In addition to his activism, Edwards is also a freelance journalist and photojournalist. He has done news-related work for New Market Press and other print and online news outlets in Vermont and New York.
"I don't see any reporters digging into the technical side of this story," he said, "it's all feel good stuff about how wonderful the college is in fighting global warming, etc. But I think this power plant is a boondoggle. I have the figures that prove it."
Edwards said he used public information from various Internet sources to estimate the "footprint" of the new plant on Addison County's local landscape. In addition, he noted that his own informal survey of area lumberyards showed a shortage of wood chips in the area. He's not quite sure where the college will find its biomass fuel.
"The fuel for the plant is supposed to come from a 75-mile radius of Middlebury," he said. "All the pollutants filtered from the air by trees and trapped in the wood within that 75 mile radius around Middlebury are going up the stack as point source pollution here. Scrubbers if they installed them only remove particulates. Burning wood is not the cleanest way to produce power."
Edwards presented the Eagle with calculations he made regarding the biomass basis of Middlebury's gasification plant. He stressed that the results of his calculations were approximate but worth sharing with the public.
Edwards said the college didn't provide the news media with many details, at least those relating to the long-term operation of the plant.
"The college says the biomass gasification plant can be a showplace for the college and a model others can use in the campaign to reduce greenhouse gas emissions," Edwards said, "but its going to be a big hog that eats a lot of wood-wood that is delivered by many trucks burning their own fossil fuel-diesel fuel."
Middlebury College says the plant is due to burn about three tons of wood chips per hour that will meet approximately half of the school's heating, cooling and hot water needs. The other half will use standard fossil-fuel oil.
"I figured that if this plant consumes 3 tons of wood per hour, multiply that by 24 hours, and it equals 72 tons per day," he said. "This isn't complicated math-72/27.5 tons per truck load equals 2.618 loads to the campus plant per day. So if you figure 2.5 truck shipments per day, times 365 days, that equals 912.5 trips a year. That's around 25,000 tons a year!"
Edwards noted the following calculated:
•No. 6 fuel oil, used in the old campus plant, produces 150,000 BTUs/gallon; wood produces 3.5 BTUs/pound. Per his calculation, 1 million gallons of No. 6 fuel oil is equivalent to 1.5 multiplied by 10 to the eleventh power BTUs. (It takes approximately 118 tanker truck loads of No. 6 fuel oil at 8,500 gallons per load.)
•One ton of wood chips equals 7,000 BTUs-extended gives 1.47 multiplied by 10 to the sixth power BTUs for the 21,000 tons of chips. "That comes up very short in the BTU department," Edwards said. Wikipedia defines a BTU (British Thermal Unit) as the amount of heat required to raise the temperature of one pound of liquid water by one degree from 60 to 61 Fahrenheit at a constant pressure of one atmosphere. As is the case with the calorie, several different definitions of the BTU exist which are based on different water temperatures and therefore vary by up to 0.5 percent.
According to Edwards, "New York State's tests on gasification show that the same types of plants operate at about 85 percent efficiency. But they burn other biomass such as manure or coal at the Dunkirk Station."
"The majority of gasification projects generate electricity; Middlebury's is heating water. There is a loss in heating water, a loss in the lines carrying it throughout the campus, and a constant requirement to maintain the temperature for demand," Edwards said. "Actually this isn't an efficient means of heating; I doubt they plan on replumbing the whole campus. There is also a lot of downtime cleaning out ash which means going back to oil backup. Trucks will also have to haul out the ash for dumping. And where is the college dumping the ash? You have to calculate that traffic into the carbon footprint, too. "
Middlebury College officials said the plant needs 21,000 tons of wood chips per year to replace the 118 tanker truck loads of bunker oil.
"My best estimate," Edwards said, "is that Middlebury College is 30 percent short on its wood chip requirement-it'll need another 6,300 tons of the stuff.
"I am sorry, but you have to now add an increased carbon footprint for the college," he said. "You can bet these trucks aren't burning biodiesel. I can't believe the college didn't perform these calculations."
Stephen C. Diehl, a spokesperson for Middlebury College, said he has not seen Edwards' calculations about the power plant.
"Our fuel is domestic fuel-it's wood harvested in Vermont," Diehl said. "I don't think Mr. Edwards has included the high cost of shipping the oil from the Middle East or Venezuela to Vermont. I think his comparisons are apples and oranges."
Jack Byrne, of the college's sustainability integration office, also said he did not see Edwards' calculations.
"Well, we're no longer buying 1 million gallons of oil," he said. "You also have to figure the high costs of getting the oil and then shipping it here from overseas."
Byrne also said that there is no need to shut down the college's new gasification plant to remove ash.
"It's not an issue. The plant keeps running," he said, "and the ash is kept in a dumpster. Laws in Brandon, Vt., will use the ash as a fertilizer, so we close the recycling loop."
But when asked to comment on Edwards' claim that the new plant will actually see an increase in truck traffic carrying wood versus truck traffic carrying fuel oil, Diehl said, "that may be the case."
"I wonder if the residents of Bridport, Weybridge, Shoreham and Cornwall are ready to receive the diesel fumes, noise, potholes and the consequences of some 912 truckloads of wood chips heading to campus," Edwards said. "I am sure the college will not be directing these trucks to campus through downtown Middlebury. With proponents of green technology it's always about intentions, not results."