By Erica Quinones
Be it through metal straws or water bottle-filling stations, Washington College has seen a steady increase in conservation and sustainability initiatives over the past couple of years. This not only affects students’ coffee-drinking habits and move-in clutter, but their utilities.
One of WC’s newest sustainability-related installations is the new geothermal field located beneath the recently renovated Cullen Hall.
Since its completed refurbishment, Cullen Hall has used its geothermal field to heat and cool the air inside, according to Director of Capital Projects Victor Costa.
Geothermal energy is the thermal energy in groundwater. This water has a constant temperature of 56 to 57 degrees Fahrenheit and is harnessed through water-to-water pumps to regulate a building’s temperature, according to Director of Sustainability Greg Farley.
Water-to-water pumps work similarly to common air-source heat pumps but are more efficient.
Air-source heat pumps use external coils with liquid refrigerant to extract heat from the air, moving said refrigerant to indoor coils where that heat is released as the refrigerant condenses back into a liquid, according to the U.S. Department of Energy’s Energy Saver resource.
A geothermal system’s water-to-water pump uses the same process to extract heat from groundwater in order to warm a building. Then the building’s heat can be moved into the groundwater to cool the interior during the summer.
“The energy necessary to run water-to-water heat pumps is less than the energy for an air-source heat pump because there’s more energy storage capacity in water than in air,” Farley said. “Any heat pump is more cost-efficient than a direct-combustion source like an oil or propane furnace, which uses a lot of fuel to generate heat.”
Geothermal was not only chosen for its efficiency compared to nonrenewable resources, but for its efficiency and accessibility compared to other alternative resources.
While geothermal is not as efficient as a solar hot-water system, it is more efficient than the most common form of solar energy generation, photovoltaic (PV)panels.
Compared to PV panels, geothermal systems are also easier to install on campus.
At a school like WC with old buildings and small, slanted roofs, “it is hard to install enough solar panels to generate meaningful amounts of electricity,” Farley said.
Another concern is the visual impact, as solar PV panels can look out of place on a historical campus.
“Geothermal heating and cooling is a robust, well-understood technology that is proven to keep energy costs down for building heating and cooling,” Farley said. “It does not cost much more to install than traditional heating and air conditioning.”
The field beneath Cullen Hall is not the only geothermal field on campus. There are three others beneath the baseball field, Kent House lawn, and the Campus Green. They heat the River dorms, Hodson Hall Commons, and both Miller Library and parts of William Smith Hall, respectively.
Currently, there are no plans to install new geothermal fields or alternative energy generators on campus, according to Farley. They are focusing on cutting energy losses before looking into more renewable generation.
However, WC recently signed an agreement with an energy-services contractor which will focus on energy and water waste reduction. As part of this agreement, they will likely install a combined heat and power plant which uses compressed natural gas for electricity generation and heating.
While this will reduce the amount of energy WC purchases and increase efficiency of the central steam plant, it is not alternative generation. It is a high-efficiency fossil-fuel technology, according to Farley.
More alternative energy generation may not be in the College’s immediate future, but Farley has a list of future endeavors to increase sustainability and efficiency on campus.