As Dartmouth Tries To Move Away From Fossil Fuels, What Role Will Biomass Play?

Oct 29, 2019

Dartmouth College had a plan to build a wood chip burning plant to heat its campus. This would have added a new biomass market for landowners and foresters within a 50 mile radius of Hanover.  

But, after months of local pressure the College said it would reconsider building the plant. Dartmouth’s decision speaks to the complexity of using wood biomass to transition away from burning fossil fuels.


Matt Patch is a seventh generation farmer. His family came up the Connecticut River in 1775 and settled in Lebanon.  

As we walked up a steep, wooded hill, he explains he’s converting this recently purchased 1,000 acre lot of land into a profitable maple sugar bush.   

“I’ve sugared all my life. I’ve got three boys that’ll come back and work with me,” Patch said.  “So, this is one more avenue to make a profit on or make a living on.” 

Matt Patch, right, with forester Brooks Weathers, left, stand on a few acres that are regrowing after they were cleared in January to make space to connect the maple trees.
Credit Annie Ropeik / NHPR

In order to make space for the maples, and connect all the tubing to carry out the sap, he needs to cut down a bunch of other kinds of trees. 

Patch has had a logging team on his property for about the last year, making space for the maples.

Heavy machinery cuts through pines and oaks in a second, grabbing them and plopping them in a pile. 

Some of the thick, straight trunks will be sold as sawlogs -- higher value lumber, maybe to make furniture. Others will become firewood. 

What’s left -- the tops, the branches, the crooked parts -- is turned into wood chips to be sold to a biomass plant in Vermont. That plant will burn the wood chips to generate electricity. 

Patch says, back in the 90s, there was a proposal to turn these thousand acres into two golf courses with condos around.  

He says harvesting — and in particular being able to sell the wood chips to biomass plants — allows it to stay a forest.  He says it’s sustainable and good for the local economy.

As we walk around, we can already see new saplings sprouting up in a section where the trees were cut down several months ago.   

For a long time in New Hampshire, the market for wood chips was pretty stable. But as paper mills closed, and biomass electric plants have gone idle, that market is shrinking. 

Recently, biomass plants in Springfield and Whitefield laid off most of their 40 workers

One section of Patch's land that's been cleared of non-maple trees. Seven months after this section was cut, new growth is already appearing.
Credit Annie Ropeik / NHPR

So, some cheered in January when Dartmouth College announced its plan to build a new wood chip burning facility to heat its campus, just eight miles down the road from Patch’s farm.  

The plant was part of the college’s plan to reduce its emissions. The proposal attracted criticism from locals, who worried about breathing dangerous particulates and added traffic from logging trucks. 

Dartmouth held public forums to talk about the site of the future plant, and planned to move forward with the plant. 

Then, at the end of September, Dartmouth announced it was reconsidering biomass altogether. 

Rosi Kerr, Dartmouth’s director of sustainability, says that decision came down to our changing climate. 

Credit Annie Ropeik / NHPR

“Let’s really understand how burning wood from the forest for heat is going to impact climate change in the near term and the future,” Kerr said. 

Whether burning wood chips for heat helps the climate or harms it she says, is a really complicated question. 

John Gunn, a University of New Hampshire forestry professor, agrees with that.  His research focuses on the different ways that forests play a role in mitigating climate change. 

He says there are a number of factors that make using wood as an energy source complicated. One of those is how trees are chosen for harvest.

“All harvests are not equal in terms of the potential outcome, so looking at the type of practices used to supply energy markets is a key piece to the whole equation,” he said. 

Gunn says all those leftover tree pieces — the branches, limbs and tree tops, also known as residuals — can just be left in the woods after a harvest.

They eventually decay, releasing some carbon dioxide into the atmosphere, with the soil absorbing the rest. 

Or the leftovers can be used to make something else, like wood chips for energy, which Gunn says, is the best case scenario. 

Brooks Weathers of Durgin & Crowell Lumber Co. inspects a tract of forestland.
Credit Annie Ropeik / NHPR

But once there is a market, over time, Gunn’s research shows it encourages harvesting whole trees to chip and burn and that, he says, increases carbon emissions. 

“[That’s] when you start to move into trees, whole trees, that would have continued to grow and sequester carbon if not for the fact that they were removed for that energy use,” he said. 

Scientists say trees play a big role in fighting climate change by absorbing a lot of the carbon that would otherwise just go into the atmosphere. 

That’s why deforestation is one of the big contributors to climate change

Bill Schlesinger, a professor emeritus at Duke University, pointed that out to Dartmouth earlier this summer. 

He and three other prominent Dartmouth alumni wrote a letter urging Dartmouth not to build the biomass plant. 

“Trees are really the best way we have to combat rising carbon dioxide in the atmosphere and climate change,” he said. 

Schlesinger and the other scientists say the college should look into solar, geothermal or heat pumps, energy sources that don’t require burning anything. 

Dartmouth's current heating facility burns number 6 fuel oil.
Credit Wikimedia Commons

But Dartmouth officials say transitioning fully to a non-combustion source in the next few years is too expensive and not logistically feasible.  

If the college doesn’t go the non-combustion route, Schelsinger says Dartmouth is better off sticking with the fuel oil they currently burn to heat campus until they can make the switch. He says that would have to be paired with major efficiency efforts.

“I would squeeze all the efficiency out of the process. I’d put in the hot water, insulate the buildings,” he said. “I’d do everything I could do to reduce carbon dioxide emissions from using oil.”  

The college is starting a major efficiency project which would provide a 20% efficiency gain: it’s upgrading its old steam distribution pipe system to new pipes that will carry hot water.  

This transition also enables the college to use different sources to generate heat beyond fuel and biomass, says Kerr, Dartmouth’s sustainability director. 

Schelsinger says he could imagine supporting Dartmouth’s wood burning plan, if the timeline for trees to regrow were different, given the urgency around climate change. 

“You don’t see the benefit of wood as a renewable resource unless you give me the 100-year time frame for the trees to regrow,” he said. “If you give me that, I might be leaning to thinking wood might be better than oil, because [oil has] been underground for 60 to 100 million years.” 

Kerr says Dartmouth has been grappling with that question.

Credit Annie Ropeik / NHPR

She says the college was trying to determine how long it would take for trees to regrow in the Upper Valley so they could sequester carbon again. 

A tipping point in the conversation came around the same time the Dartmouth alumni wrote their letter. A new report from the United Nations climate panel came out, saying that reducing greenhouse gases from all sectors, including land and food, is essential to keeping global warming below 2 degrees Celsius. 

“That report shortened the timeframe for meaningful action on climate, if what the IPCC is saying as our read of it is, we need to be doing more faster,” she said. 

Kerr says the big goal here is for Dartmouth to one day have a system that burns very little or nothing at all. But until they get there, the college needs a bridge.

The proposed biomass plant could have been that bridge, running for about 20 to 30 years. But the IPCC and Kerr now say a lot needs to be done in the next 10 years, not 20 or 30, to reduce carbon emissions faster. 

Kerr saw how this conversation is playing out in a recent trip to Denmark. In the 70s, Denmark made a commitment to transition to a low carbon future

“They are now in a situation where they’re using low temperature hot water and district heating, and they’re using low carbon technologies to put heat into district heating systems,” Kerr said. 

But communities there are also using a lot of biomass, and a similar conversation is playing out as those communities try to shift away from these plants. 

“And the question I came away from that experience with is can we get over the bridge sooner and faster and skip the biomass step that Denmark went through?” 

Now, Kerr says she’s thinking, maybe the way to get over the bridge is to do a little bit of everything.

“I think there’s a middle ground where maybe we burn liquid biofuels in our current plant; we add small scale biomass that’s super sustainable in our plant, similar to what lots of high schools in New Hampshire have done,” she said, “And maybe we deeply invest in energy efficiency and geothermal.” 

These kinds of environmental decisions aren’t simple ones to make at a scale like Dartmouth’s, she says. 

“When you multiply that by 5.5 million square feet, with thousands of people coming and going everyday, it’s much more complex than the decision making in your own home, in my home, about environmental pros and cons.” 

But reconsidering a new biomass plant does mean there may not be the big, new woodchip market some in the region had hoped for, leaving foresters and landowners wondering what’s next for them.

This is the first of a two-part series. Listen to part two, on potential new markets for low-grade wood and the obstacles to developing them in New Hampshire.