HANOVER — A group of prominent scientists and Dartmouth College alumni are urging the school to cancel its plans to build a biomass plant to heat the downtown Hanover campus as part of its $200 million “green energy” plan.
Burning wood chips could “substantially” increase the college’s carbon emissions and worsen the effects of climate change, the scientists said in a letter to the Dartmouth community dated July 5.
“We urge you to avoid making a heavy investment in a mistaken assumption that a wood-fired heating plant will be of benefit to the College or the world,” they wrote in the letter.
It was signed by George Woodwell, a 1950 Dartmouth graduate and founder of the nonprofit Woods Hole (Mass.) Research Center; William Schlesinger, a 1972 graduate and emeritus dean of Duke University’s Nicholas School of the Environment; and John Sterman, a 1977 alumnus, professor at the Massachusetts Institute of Technology and director of its Sustainability Initiative.
The three argue that carbon dioxide released from wood-burning plants is greater than the fuel oil Dartmouth currently relies on. The carbon content of wood is about 30% greater than fuel oil and 80% higher than natural gas, they said.
“It’s absolutely essential that we reduce the emissions of carbon dioxide going into the atmosphere,” Woodwell said during a phone interview on Wednesday.
Forests are a major pool of carbon dioxide and globally store as much carbon as Earth’s atmosphere, he said. Carbon is released both when wood is burned and after a tree is cut through soil and decaying plant material.
And while forests are renewable, it could take 100 years after cutting before they’re able to again absorb the same levels of carbon, said Woodwell, who drew early attention to the dangers of climate change and was a founding trustee of the Natural Resources Defense Council and a founder of the Environmental Defense Fund.
“We don’t want to cut forests and burn them up, dumping carbon into the atmosphere because it makes a problem that is now desperately serious much worse,” he said.
Woodwell and his co-authors say Dartmouth should endeavor to make its buildings more energy-efficient, retrofitting them to better retain heat.
Officials should also look to alternative forms of energy, including solar, wind and water, they said.
Biomass heating systems are becoming more common in northern New England. Middlebury College, Sachem Village in Lebanon, Hanover High School, and the Richmond and Lebanon middle schools are just some of the institutions that are fueled on wood pellets.
The Grafton County complex in North Haverhill is also heated by wood chips.
Advocates argue the market for low-grade lumber used in the heating process provides forest managers and landowners with money to cultivate lumber-quality timber.
Both are an important economic driver in the North Country economy.
Dartmouth contends that the scientists are confusing biomass as a heat source, which the college proposes, with electric generation.
“Burning biomass for electricity is, as you point out, incredibly inefficient in terms of carbon, dollars and energy,” Rosi Kerr, Dartmouth’s director of sustainability, and Josh Keniston, its vice president for institutional projects, wrote in a response on Wednesday to the letter from the alumni scientists.
The college estimates that burning wood chips to heat a hot water distribution system is 89% efficient, meaning more energy could be recovered than in most electric plants.
The officials also outlined several steps Dartmouth has taken and plans to increase energy efficiency in other ways.
Of the $200 million it hopes to soon invest in biomass, about two-thirds is slated to go toward a conversion from steam to hot water, which could increase efficiency 20%, Kerr and Keniston wrote.
Since 2005, Dartmouth has also invested “tens of millions of dollars” retrofitting buildings, and upgrading insulation, windows and HVAC systems. It’s also installed solar panels on several rooftops, which cover about 2% of the college’s overall energy use.
As for solar, wind or geothermal energy — none could fully heat the campus without the help of a combustion-based fuel, college officials said.
“In addition, these strategies are cost-prohibitive at nearly five times the capital cost and three times the operating costs of business as usual,” they wrote.
But Dartmouth will need to do more than just increase efficiency to decrease greenhouse gas emissions, said Andrew Friedland, an environmental science professor at Dartmouth and co-chairman of the college’s 2017 Sustainability Task Force.
Over the last few years, science has shown that biomass is more environmentally detrimental than originally thought, he said.
While some experts believed the fuel could be carbon-neutral, even in the best cases, biomass is likely only neutral over 100 years, Friedland said. That’s because it takes at least a century to regrow forests.
“There’s going to be a solution sometime sooner that will work better,” he said, also advocating for Dartmouth to put the brakes on biomass.
The college has scheduled two community forums this summer to discuss three possible sites for the biomass facility.
The sites, which were announced in May, include the hill behind the Dewey parking lot near Route 10, land by Hanover Country Club’s maintenance facility garage near the south end of the golf course and the former home of Trumbull-Nelson Construction Co. on Route 120.
The first forum is at 6 p.m. on Wednesday and the second is on 6 p.m. on Aug. 13.
Both will be in the Filene Auditorium in Moore Hall.
Tim Camerato can be reached at tcamerato@vnews.com or 603-727-3223.