Calculating the University of Hawaiʻi at Mānoa Environmental Footprint from Food Procurement at Sodexo Cafeterias; Nitrogen, Carbon and Water Withdrawal

Abstract

Tracking an organization or campus’s environmental footprint can shed light on those activities and operations that contribute the most emissions to or withdrawals from the environment. This work investigates the environmental footprint, specifically nitrogen and carbon emissions, as well as water withdrawals, that result from the University of Hawaii at Manoa’s (UHM) Sodexo cafeterias. An additional objective of this work was to create the foundational methods and procedures for measuring and estimating the emissions from all campus food procurement. To execute this objective, the system boundaries were defined, and a central database was designed into which mass amounts resulting from all food procurement is be aggregated and converted to their respective carbon and nitrogen emissions as well as water withdrawal. To communicate those food categories that contribute the most to the aggregate footprint, food inventories were broken down into their top three ingredients which were then placed into common food categories. Conversion factors were then applied to convert mass (kg) quantities in each food category to mass (kg) contributions to each environmental footprint (N emission, C emission, H2O withdrawals). Results revealed that beef had the largest contributions to the environmental footprints while pork and cheese followed closely behind, indicating that animal products are likely the largest contributors to UHM’s environmental footprint.