# Towards a Climate-Neutral Campus: Carbon Footprint Assessment in Higher Education Institutions
## 1 Introduction
### Literature Review  
Extensive research has explored CF assessments in various sectors, including HEIs. Studies have examined the carbon emissions associated with campus operations, student and staff commuting, and embodied emissions in construction and procurement [15; 20; 21; 22]. However, there remains a need for more comprehensive and standardized methodologies for assessing CF in HEIs, particularly concerning the inclusion of indirect emissions and the development of effective mitigation strategies. Universities often struggle to accurately report their GHG emissions, particularly the emissions categorized as Scope 3. While most institutions report direct emissions from owned or controlled sources (Scope 1) and indirect emissions from purchased energy (Scope 2), the complex and often much larger Scope 3 indirect emissions, which occur across the entire value chain, are frequently incomplete or missing. This is largely due to challenges in data accessibility and availability [15; 22]. Although some Scope 3 categories, like waste, business travel, and commuting, are commonly included in university GHG inventories, others, such as procurement-related emissions, are often overlooked [22; 23]. The sheer number of Scope 3 categories (fifteen in total) and the variability in data collection methodologies contribute to inconsistencies and underreporting, making it difficult to compare emissions across institutions. Several studies illustrate the variability in Scope 3 emissions reporting. [PERSON] et al. [24] included business travels, commuting, wastewater, waste, paper, and fertilizer, while [PERSON] et al. [25] accounted for water, wastewater, paper, business travels, commuting, waste, construction, and transportation and distribution losses from purchased electricity. [PERSON] et al. [21] considered business travels, commuting, paper, and waste, while [PERSON] et al. [26] included a broader range: business travel, property maintenance, general procurences, IT equipment, paper, waste management, restaurant services, and commuting. This lack of standardization and data accessibility hinders the accurate assessment of true environmental impacts and impedes the development of effective emissions reduction strategies. The discrepancy in reported Scope 3 emissions is substantial: some studies suggest they represent up to 90% of a university's carbon footprint [27; 28; 29], while others estimate a much lower contribution of around 18% [30]. This wide range highlights the urgent need for improved methodologies and data collection to accurately capture the full extent of university emissions. This inconsistency has raised concerns among environmental professionals regarding potential biases in the representation of institutions due to varying accounting methods for indirect emissions [31; 32].  
To accelerate carbon neutrality, universities must meticulously track both on-campus carbon emissions and sequestration potential while minimizing waste, maximizing energy efficiency, and exploring innovative carbon offset strategies like implementing nature-based solutions, technology-driven innovations, circular economy practices, and community engagement [21; 22; 26]. By effectively implementing these strategies and sharing their experiences through case studies, universities can not only achieve carbon neutrality but also serve as inspiring models for sustainable development, paving the way for a future where cities and communities coexist harmoniously with the environment. This collective knowledge, gained from diverse case studies, can further refine existing methodologies, enhance the transparency of carbon assessments, and empower other institutions, especially local authorities, to embark on their own sustainability journeys [24; 32].