Photo courtesy of WGisol via Wikimedia Commons. Geothermal heating can be installed vertically, horizontally, or diagonally. The College is beginning to plan geothermal distribution loops on campus.
By Catelyn Fitzgerald ’23
Science & Environment Editor
Mount Holyoke College’s Board of Trustees recently brought the College a step closer to achieving carbon neutrality by 2037. The Board voted to transition the College’s heating and cooling system to one powered by geothermal energy. The decision was shared with the MHC community in the Oct. 19 edition of the MHC This Week newsletter, alongside other updates from the Board’s fall meeting. The transition to geothermal power, which the meeting summary referred to as the “College’s Energy Master Plan,” would reduce the College’s carbon footprint by an estimated 80 percent, per the summary.
In an interview with Mount Holyoke News, Raghu Raghavan, the College’s director of sustainability and associate director of the Miller Worley Center for the Environment, said that he had been working on transitioning the College away from natural-gas powered heating since he began working at the College in 2020. He explained that the carbon neutrality goal emerged from the recommendations of the Sustainability Task Force in 2018. Subsequent planning involved having consultants evaluate different ways for the College to reach its carbon-neutrality goal, Raghavan explained. He went on to state that the same group of consultants had previously worked with other schools in the Pioneer Valley. The resulting plan was “not very different from what they proposed to Smith [College] and Amherst [College],” Raghavan said. “We needed a solution that was geared towards the pretty strong heating requirements in the long winters,” he explained as to why geothermal emerged as the best solution.
Raghavan also emphasized the role of Interim President Dr. Beverly Daniel Tatum in the project’s success. “The day she set foot on this campus, she pushed this project [through to the Board],” he said, adding that Tatum “commands a lot of respect.”
According to the United States Department of Energy, geothermal heat pumps work by utilizing the earth’s near-constant temperature. The USDE explains that heat pumps circulate a fluid, such as water, through pipes that form a loop between the ground and nearby buildings. When the air temperature is cooler than the ground, the fluid will absorb heat as it travels underground and then release that heat as it travels through a building. The reverse happens when the air is warmer than the ground, as the fluid absorbs heat from inside buildings and carries it underground, where it is released.
According to Raghavan, Mount Holyoke’s current heating system circulates 200 F steam through the buildings. He went on to explain that 50 percent of this heat is lost during the distribution. In contrast, he explained, hot water systems such as some geothermal heat pumps experience much less energy loss during distribution and only need to be heated to 130 F to be useful for water heating.
Geothermal energy represents a short-term investment with long-term payoffs, according to an article from EnergySage, a solar energy resource site and marketplace. This article explains that upfront costs for a geothermal heat pump are high, particularly when ductwork needs to be installed or replaced, to which Rhagavan said the College will need to conduct excavation processes. Once the upfront investments are made to install the heat pump, however, energy-cost savings are significant, and in a household setting, the system will typically pay itself off in five to seven years, the EnergySage article said.
According to an United States Environmental Protection Agency article, geothermal energy is not inherently fossil fuel free. Geothermal heat pumps require some electricity to heat or cool the water further so that it can reach the desired temperature, the EPA article explained. This means that it is the responsibility of the user to source the additional electricity from a renewable source in order to minimize its environmental impacts.
Geothermal heating and cooling brings with it the benefits of producing energy on-site rather than purchasing it from the grid, per the EPA. On-site renewable energy production shields users from volatile fossil fuel prices and grid blackouts, allowing users to better predict future energy expenditures. Additionally, on-site renewable energy production puts money back into the local community through job creation and long-term financial savings, the EPA explained.
According to Raghavan, only phase 1A of the “Energy Master Plan” was approved during the recent Board meeting. This first phase consists of planning the distribution loops for the new hot water system. For the project to continue, subsequent phases will also need to be approved by the Board, potentially during their spring meeting, he said. If the process goes smoothly, Raghavan says that he expects digging for the new system to begin in the summer of 2023.
Raghavan made it clear that switching to renewable energy is not the be-all and end-all of a sustainable future. Rather, geothermal and other technology-based solutions should be viewed within the larger context of overconsumption and adopted alongside reductions in energy use. Maintaining a focus on emissions reduction is “comfortable,” Rhagavan said, but the College’s community also needs to address issues of justice and lessening energy consumption as it strives for sustainability.