While Princeton faculty members are making waves with their work across the globe, they are also leading the way to a more sustainable campus, using Princeton as a living laboratory for research and innovation.
Focusing on fume hoods
On each of the 16 fume hoods in Professor Tom Muir’s lab in the Frick Chemistry Building, a sticker of a tiger stands guard behind the words: “CLOSE THE SASH.”
Why? A single hood can consume more energy than the average U.S. home. The stickers are part of an integrated behavioral science approach for cutting laboratories’ energy consumption across Princeton’s campus. Comprising only 13% of Princeton’s physical footprint, labs are responsible for almost 50% of the campus’s energy use. Fume hoods, which are ventilated enclosures designed to protect people working with chemicals from hazardous fumes, are a large component of a lab’s energy consumption, because the conditioned air used in a fume hood is exhausted to the outdoors and cannot be recirculated.
The team, advised by Elke Weber, the Gerhard R. Andlinger Professor in Energy and the Environment and professor of psychology and public affairs, has demonstrated a 24% reduction in energy use from fume hoods by harnessing tools from behavior science that encourage users to close them when not in use. These tools include stickers reminding users to shut the fume hood, a dashboard alerting lab managers when a fume hood has been left open for too long, and a monthly progress report.
“Behavioral science helps us call attention to and correct some of our bad habits, which could be behaviors that people might not even register as problematic until they’re made aware of the consequences,” said Weber.
Breaking ground on geo-exchange
When Princeton announced its decision to install a geo-exchange system to help meet its commitment to net-zero campus emissions by 2046, Forrest Meggers saw an opportunity to collect valuable data.
Meggers, an associate professor of architecture and the Andlinger Center for Energy and the Environment who researches ways to develop more efficient heating and cooling systems, helped with prototyping for the system. His contributions included setting up the sensing system for an over 1,800-foot-deep test borehole designed to find the ideal number and depth for the wells that will ultimately comprise the geo-exchange system.
The final system, with over 2,000 wells, will operate as a high-efficiency thermal “piggy bank.” During the summer, excess heat removed from buildings will be stored underground using the geo-exchange bores. That stored heat will be used to warm campus buildings during the winter.
Meggers was particularly interested in leveraging the deep test borehole to inform research in his lab. “The ground gets warmer as you continue to drill,” said Meggers, who also served on Princeton’s Infrastructure Master Plan committee. “With such a deep test borehole, I could take measurements and develop models to understand how the resulting thermal gradient increased the system’s efficiency.”
While the majority of the installed geo-exchange boreholes are much shallower than the test bore — extending between 600 and 850 feet below ground, depending on their location on campus — Meggers said his experiments provided data that will help his research team develop better heat exchange technologies.
