By JOHN P. GREGG, Valley News Staff Writer, Tuesday, September 24, 2019
HANOVER — Dartmouth College is reconsidering whether to rely on a proposed biomass plant to heat its campus after prominent alumni environmentalists said burning wood chips contributes to global warming.
“At this point, biomass is still on the table, but we are going through a process to kind of confirm if that makes sense,” Josh Keniston, the Dartmouth’s vice president for institutional projects, said in a phone interview on Tuesday.
Keniston oversees the so-called Dartmouth Green Energy Project, the college’s $200 million plan to switch from steam heat to a hot-water heating system and to replace its 121-year-old oil-burning power plant in downtown Hanover.
He said the college is looking at “non-combustion” energy sources as an alternative to the proposed biomass plant.
Keniston ruled out natural gas and nuclear power and said Dartmouth was assessing such energy sources as solar power, wind turbines, hydropower, and ground-source and air-source heat pumps.
“It’s essentially anything that doesn’t combust, that doesn’t have a fuel you are burning,” Keniston said. “So it’s a lot of electric-based technology.”
Dartmouth signaled it was re-assessing the biomass proposal in an announcement following the fall meeting of its Board of Trustees over the weekend in Hanover. The announcement expressed support for the green energy project, noting it is expected to improve heating efficiency by 20% in replacing steam pipes in more than 100 buildings across its campus.
But, notably, the announce did not mention biomass, instead saying, “The board will remain engaged as the administration team continues to analyze the project’s energy-generation source.”
Keniston, who helped brief trustees on Saturday, said, “Part of what we are looking at is the technology changes quickly, and we are evaluating if any of the recent changes in either the technology or understanding of how various technologies impact climate change, if any of those would suggest a different path.”
The shift also followed impassioned calls, letters and community forums about the biomass project, with some Dartmouth alumni and Upper Valley residents contending that rather than leading on renewable energy, the college would be adding to global warming if it burned wood chips and released that carbon from trees.
A group of prominent scientists and environmentalists also have said burning wood chips could “substantially” increase the college’s carbon emissions. Some others have backed the proposal, saying it will help provide a market for low-grade wood in New Hampshire forests and also benefit the local economy.
George Woodwell, a 1950 Dartmouth graduate who has helped lead the opposition to the biomass plant, organized a meeting with prominent scientists for Keniston and Rosi Kerr, Dartmouth’s director of sustainability, last month at the Woods Hole Research Center in Massachusetts. Woodwell founded the acclaimed environmental research institute on Cape Cod and was also a founding trustee of the Natural Resources Defense Council and a founder of the Environmental Defense Fund.
Woodwell on Tuesday said he was “delighted” to learn that Dartmouth was considering other options to biomass.
“The college has a big challenge in that they have more than 100 buildings that they have to deal with. It’s entirely possible to have a program that phases out combustion and works in alternative sources — ground source heat pumps and air source heat pumps and improved efficiency in the use of energy — in all phases, and the college ought to be doing that and should be a leader, in fact,” Woodwell said.
Dartmouth has identified three sites for a possible biomass plant: on a hill behind the Dewey parking lot; land by Hanover Country Club’s maintenance facility garage off Route 10; and the former home of Trumbull-Nelson Construction Co. on Route 120. Keniston said a decision on the designated site, which was planned for this month, has been pushed off as Dartmouth re-evaluates its energy source.
He also declined to say if Dartmouth, which owns large tracts of land in northern New Hampshire, might consider building solar arrays or wind turbines there.
“It’s too early for us to know,” Keniston said. “I think the work we are doing now is to see what the options would be.”
Woodwell said it was conceivable that Dartmouth could purchase an interest in a large wind-turbine project not on college land, and “own a piece of it.”
“The whole transition to renewables is a transition to electric power; there’s not much question,” Woodwell said. “It will come from a number of sources.”
John P. Gregg can be reached at firstname.lastname@example.org.
Here are some wood burning articles for reference:
SOME COMMENTS BY WILLEM POST
Dartmouth folks were planning to implement an environmentally damaging tree burning heating system for its campus that would not have been sustainable for many, many years, because the combustion CO2 would be absorbed by biomass regrowth on the harvested area over a period of about 90 to 100 years, which starts AFTER THE C-NEUTRALITY PERIOD, which could last up to about 35 years in northern climates, such a northern Vermont, northern New Hampshire and all of Maine. See this URL
I have been advocating ground source heat pumps for heating and cooling and providing hot water to Dartmouth campus.
In New England, AIR source heat pumps are suitable only for highly insulated/highly sealed buildings, which would have low peak heating demands during the coldest days.
In New England, AIR source heat pumps are UNSUITABLE for ALL other buildings, i.e., about 98% of all buildings in New England, no matter what various non-technical, self-serving bureaucrats say. Do not listen to them, as you will regret it later.
Note for Lay People: At low air temperatures, the delta T of the air and refrigerant is very small, thus only little heat can be extracted from the air, i.e., heat pump output, Btu/h, decreases at exactly the same time the building heating demand, Btu/h, is increasing. Gee whiz, no wonder they do not work in cold climates.
However, some heat pump models do a little cheating. They have a built-in electric resistance heater to increase the heat output at low temperatures. That creates the false impression to lay people the heat pump is “working” when it is cold.
The following heat pump articles will provide a good education:
A RATIONAL APPROACH FOR DARTMOUTH
The only rational approach for Dartmouth is to:
1) Insulate and seal the existing and any new buildings as much as possible, so they will use the least Btu/sq ft/y for heating, cooling, hot water and electricity. The advantage is that the capacities of any heating and cooling systems would be minimal, and that any electricity purchased under power purchase agreements would be minimal.
2) Enter into power purchase agreements with owners of wind, solar and hydro systems equal to all electricity consumption of the Dartmouth campus. The electricity from these three sources has minimal CO2 emissions. So Dartmouth can brag about that, as do many other entities.
Those agreements would be paper contracts, not physical contracts, because, in reality, all electricity fed into the New England grid anywhere, instantaneously becomes part of the mix on the NE grid, so any electricity drawn from the NE grid is that mix.
Electricity travels on the grid as electro-magnetic waves at near the speed of light, i.e., from northern Maine to southern Florida in about 0.01 second. Any talk by lay people of there being a Vermont mix, or New Hampshire mix is a pure fantasy. See Appendix
The NE grid CO2 emissions were 322 g/kWh in 2016 and 309 g/kWh in 2017, as calculated by NE-ISO, the grid operator. Those values should be increased by about 7.5% to account for transmission and distribution losses from generator to user meter. Dartmouth can still brag about that, because it is much better than the US grid.
Here are examples of ground source heat pumps:
There are around two million single-family houses in Sweden, and approximately 20-25% of these houses are heated with a GSHP (2015 status)
They work great no matter the outside temperature, because the ground temperature always is about 55F, when outside it is about -20F in winter.
My cousin lives on the ninth floor of a 12-story modern, condo building in Maassluis, the Netherlands.
The building is part of a housing complex of 20 buildings entirely provided with heating, cooling and domestic hot water from ground source heat pumps already for more than 35 years.
In the Netherlands, all that is old hat, routine BAU.
Highly Sealed, Highly Insulated Buildings and Heat Pumps is a Much Better Approach
A central plant, burning whatever, with hot water distribution system is ancient, 100-y-old technology.
Dartmouth would not lead, but be laughed at.
It would be much better for Dartmouth College to become really modern, i.e., use ground source heat pumps in highly sealed, highly insulated buildings to provide heating and cooling. They could have multiple holes up to 1000 ft deep, or have piping systems under parking lots, etc.
The students would actually learn from such a setup
The students would also learn, the forests, left undisturbed, would maximize C storage.
By clustering geothermal loops, an old-fashioned central plant would not be required.
One could still have a loop tying together the clusters.
It would act as storage of any waste heat, and supply peak demands.
That entire system could be powered by local and remote wind and solar, supported by sufficient capacity batteries.
NOTE: The present, 50-y-old steam distribution system is highly inefficient and should not be used as a rational basis for comparison with new hot water and $savings calculations and CO2 reductions, as Dartmouth did. The comparison basis should be modern vs. modern, not modern vs. decrepit.
NOTE: Here are some URLs of ongoing ground source heat pump projects at universities. No wood chips required.
Electricity Mix Based on Power Purchase Agreements: There are non-technical people talking about the “Vermont electricity mix” or the “New Hampshire electricity mix”. That mix exists only on paper, because it is based on power purchase agreements, PPAs, between utilities and owners of electricity generators. A utility may claim it is 100% renewable. This means the utility has PPAs with owners of renewable generators, i.e. wind, solar, biomass, hydro, etc. That mix has nothing to do with physical reality.
Electricity Mix Based on Physical Reality: Once electricity is fed into the NE electric grid by any generator, it travels:
- On un-insulated wires, as electromagnetic waves, EM, at somewhat less than the speed of light, i.e. from northern Maine to southern Florida, about 1800 miles in 0.01 of a second, per College Physics 101.
- On insulated wires, the speed decreases to as low as 2/3 the speed of light, depending on the application.
If those speeds were not that high, the NE electric grid would not work, and modern electronics would not work.
The electrons vibrate at 60 cycles per second, 60 Hz, and travel at less than 0.1 inch/second; the reason it takes so long to charge a battery.
It is unfortunate most high school teachers told students the electrons were traveling.
Teachers likely never told them about EM waves, or did not know it themselves.
This article explains in detail what happens when electricity is fed to the grid.
NOTE: If you live off the grid, have your own PV system, batteries, and generator for shortages and emergencies, then you can say I use my own electricity mix. If you are connected to the GMP grid, which is connected to the NE grid, and draw from any socket, then you draw the NE mix.