AMHERST — The use of a fuel known as “renewable diesel” being at the central heating plant at the University of Massachusetts on the coldest days of the year, in place of liquefied natural gas and ultra-low-sulfur diesel, is raising worries for some faculty members and other campus leaders about compromising the UMass Carbon Zero plan unveiled on Earth Day 2022.
A letter sent to UMass Chancellor Javier Reyes on Jan. 6, about a month after the Faculty Senate got an update on the ongoing carbon footprint reduction efforts, is questioning the university’s climate commitment because renewable diesel is being used, in place of other renewable solutions, for providing electricity and heat on campus.
“The fuel known as renewable diesel has unacceptable performance in terms of greenhouse gas emissions, local co-pollution and global dispossession and hunger,” states the letter, signed by nine faculty members, the presidents and vice presidents of the undergraduate and graduate student government associations and others. “We are particularly concerned that the process leading to this decision is not consistent with the principles of transparency and shared governance that underpin UMass Carbon Zero.”
Deputy Chancellor for Operational and Organizational Strategies Tilman Wolf, who gave the December presentation to the Faculty Senate, said in a phone interview Friday that renewable diesel is an option being used on a limited basis as one component of a larger strategy to meet climate goals.
According to the U.S. Department of Energy, “Renewable diesel is a fuel made from fats and oils, such as soybean oil or canola oil, and is processed to be chemically the same as petroleum diesel,” though it’s been shown to produce less carbon dioxide and nitrogen oxide emissions than petroleum diesel.
Wolf took the Faculty Senate through the carbon footprint report, which covered the extent of electrification of new buildings and renovations to accommodate changes; the use of electric heat pump technology, both air-source and ground-source; storing energy seasonally through ground-source heat exchange and storing energy daily through a thermal energy storage tank; and the use of renewable energy and energy sources with a low or no carbon footprint, such as renewable fuels and solar power.
All are part of UMass Carbon Zero, announced by former Chancellor Kumble Subbaswamy to be more aggressive in meeting the state guidelines to be carbon neutral by 2050.
But Wolf said it’s a challenge to move to electric heating and cooling on a campus where steam has been predominant for heating, with a network of pipes to all buildings from the central heating plant. It will be expensive to move to a ground-source or air-source heat exchange, where low-temperature hot water is used in place of steam. Because of this, the central heating plant is staying online for the foreseeable future, and continues to mostly be powered by pipeline gas before there is a transition to fuels with less of a carbon impact.
Lori Gardner, a physics professor who chairs the town’s Energy & Climate Action Committee and who signed onto the letter, said there are questions around renewable diesel and whether it is carbon neutral, even as UMass received a report indicating this in a study completed by Waldron Engineering and Construction of Exeter, New Hampshire.
During January meetings of the town committee, Goldner said it is disturbing that renewable diesel is being used in the UMass power plant, and is not just as a little bit of supplement as UMass moves toward electrification, saying it could replace entirely the pipeline gas at central heating plant.
“Their plan is to convert their methane-burning, natural gas-burning co-generation plant to a diesel-driven, dirty (plant),” Goldner said.
The land-use changes to create this type of fuel, along with the fertilization, refinement and transportation, make the fuel deeply problematic, Goldner said. When such fuel is produced in a country like Brazil, it means cutting down palm trees, she said.
“It’s ramping up very fast,” Goldner said. “It’s larger than just UMass, and it’s disastrous.”
Wolf said that such conversion at the central heating plant is possible, but it’s not a decision yet made. Even though the carbon output is lower, the fuel is more expensive than LNG and is used only on the coldest days, when spiking demand curtails gas supplies. Wolf said the Chancellor’s Sustainability Advisory Committee, which brings together, will on this topic, expecting input from the manufacturers and federal agencies to learn more about how it is produced and to understand the broader issues, such as whether it incentivizes damaging changes to land use.
“We’re aware of that, and that will be part of the conversation,” Wolf said.
Last September, the central heating plant manager received permission from MassDEP to adjust the definition of ultra-low-sulfur diesel so that renewable diesel could be used, “since there is no increase in facility emissions, that this change is in conformance with current air pollution control engineering practices and is in compliance with the administrative amendment regulations contained in” the state code.
The carbon footprint reduction report presented to the Faculty Senate states that renewable diesel is created from feedstock that absorbed carbon during production, its combustion does not add net carbon to the atmosphere, and a “test burn” in last summer had a successful emissions evaluation.
The Energy & Climate Action Committee is drafting a letter outlining its concerns with the university’s climate plan that will go to Town Manager Paul Bockelman and the Town Council.
Committee members have observed that the town’s efforts to reduce greenhouse gas emissions are dependent on the work being done at UMass, as well as at Amherst College, which is undertaking a campuswide geothermal project to decarbonize the campus by 2030, and Hampshire College, which two years ago achieved carbon neutrality.
Committee member Laura Draucker said a concern about bio-based fuels is they are not low emitting, they have continued combustion and the possibility of reducing the efficiency of the central heating plant, and there is uncertainty about the expectations UMass is setting for the supplier.
“While we understand the need for UMass to be flexible and explore different pathways toward 100% renewable energy, we have some concerns that the use of renewable diesel fuel will not move us toward our collective climate goals,” the draft letter reads.
