Comparative study of development scenarios to decipher carbon emissions of new/old campuses in China with urban building energy model: A case study of Southeast University

The students receiving higher education boosted a total increase of 416.45% in China in last 20 years, resulting in newly built campuses reaching over 4.4 billion m². Therefore, implementing low-carbon development on university campuses is an important part of achieving carbon neutrality in China. In this study, the old and new campuses of Southeast University in China were selected and the Rhino Grasshopper tool was used to create and calibrate their energy model with real electricity data to ensure the 20% error range. The calibrated energy model was used to set up four base scenarios under different development paths in year 2030 and 2050, including natural development, campus construction, policy-oriented, and sustainable development. The simulation indicates that campus construction leads to the greatest increase in carbon emissions, with the old campus and new campus experiencing a 16.7% and 162.9% rise, respectively, compared to the current situation. In contrast, policy-oriented scenarios result in the most significant reduction in emissions, decreasing by 121.4% and 114.5% for each scenario, respectively. Only policy-driven approaches will enable both campuses to achieve carbon neutrality by 2050. The driving factor decomposition analysis indicates that in no-policy-intervention scenarios, the primary contributors to carbon emissions are short-term climate fluctuations and aging equipment. Conversely, in scenarios with government intervention, the pivotal elements are the implementation of renewable energy and the development of low-carbon technologies. The results of the static scenario combination show that the old campus has a significant lower average carbon emission of 7,080 t than 279,090 t of the new campus in 2050. However, the new campus shows higher potential, with a proportion of 38.3% achieving carbon neutrality in the combination results, compared to 17.2% for the old campus. The study results offer insights into the pathway for universities to achieve carbon neutrality, emphasizing the significance of policy direction and the adoption of renewable energy.