# Towards a Climate-Neutral Campus: Carbon Footprint Assessment in Higher Education Institutions
## 4 Results  
TUCN's carbon footprint, encompassing all three Scopes, amounted to 7445.1 tCO2e/year in 2022. This figure exhibited a slight decrease to 7229.1 tCO2e/year in 2023. For an easier comparison with other HEIs, the CF was calculated on a per-person basis. In 2022, emissions were 0.378 tCO2e/person, and in 2023, they decreased to 0.362 tCO2e/person. These calculations were based on a total of 19,722 and 19,985 individuals (students, academia, and staff) in the university community, respectively. Additionally, a footprint of 31.2 kgCO2e per square meter (kgCO2e/m2) was calculated in 2022, which decreased to 30.3 kgCO2e/m2 in 2023. These figures were determined using the university's occupied indoor area of 238,678 m2. Next, a detailed CF breakdown by category is visualized in Figure 4, with corresponding numerical data provided in Table 1.  
Stationary fuel use, primarily natural gas, represented the most significant contributor to TUCN's CF in both 2022 and 2023, accounting for approximately 62.7% and 66.9%, respectively. This substantial reliance on fossil fuels for heating and domestic hot water generation is largely attributable to TUCN's location in a region classified as a humid continental climate (Dfb) according to the Koppen climate classification system [39]. This climate type experiences cold winters and warm summers, requiring significant energy for heating during the 6-8 coldest months. The observed increase in Scope 1 GHG emissions by 3.6% from 2022 to 2023 is directly linked to the completion and subsequent use of two university facilities that had previously undergone refurbishment. These newly operational buildings contributed in 2023 to increased direct emissions. Concurrently, the decrease in waste from operations observed between 2022 and 2023 is a consequence of the reduced construction and demolition waste associated with the completion of the renovation project. Table 1 presents Scope 2 GHG emissions in accordance with the GHG Protocol's dual reporting requirements, utilizing both location-based and market-based methodologies. However, the total emissions presented in the table are derived exclusively from location-based emissions data due to higher values and do not incorporate the market-based emissions. The observed increase of electricity GHG emissions by 7.1% from 2022  
Figure 4: TUCN’s carbon footprint by category in % for the year 2022 (**left**) and 2023 (**right**). to 2023 can be attributed to a combination of factors, primarily driven by the university's evolving operational activities. Notably, the completion and subsequent use of the refurbished facilities played a significant role. These facilities, now fully operational, naturally increased the university's overall energy demand, leading to higher electricity consumption. However, when isolating the natural gas consumption of facilities operational in both 2022 and 2023, a more modest 1.5% increase in Scope 1 emissions is observed. This suggests that the increase in natural gas usage in existing facilities may be influenced by external factors, such as variations in outdoor temperatures between the two years, which would affect heating demands. Going further with Scope 2, the negative value of \(-\)2.39 tCO\({}_{2}\)e reported in Table 1 for self-generated renewable energy represents a net emission reduction resulting from TUCN's 2023 installation of a photovoltaic (PV) system. This value is an accounting adjustment reflecting the offset of emissions attributable to the renewable energy generated. Scope 3 emissions represent a significant portion of TUCN's overall CF, accounting for approximately 28.3% and 23.1% of total emissions in 2022 and 2023, respectively.