A new approach for the hourly calculation of CO2 emission factors of the thermal energy production in District Heating Systems

Reducing the environmental impact of anthropic activities is critical and requires a proper analysis of CO2 emissions. This study focuses on the thermal energy sector's emissions carbon footprint, which is essential for many public and private institutions. The current practice of using average national and annual emission factors (EFs) may lead to inaccurate results on specific local entities, particularly in the case of combined heat and power production. This study aims to refine the EF calculation considering a combined cycle cogeneration plant and an hourly time step for the analysis. The case study chosen is the district heating system (DHS) cogeneration plants of Turin, one of the largest DHSs in Europe. The defined thermal EF is applied to the user case study of Politecnico di Torino supplied by the DHS. The study focuses on the thermal energy needs of the university campus on an hourly and seasonal scale. The results reveal that the emission factor of a DHS calculated with this methodology is different from the one calculated with other methodologies or using national EFs, better representing the real situation. Since the load profile of a university facility represents tertiary sector energy activities, the methodology used in this study is easily replicable in different contexts. This study emphasizes the importance of accurately estimating CO2 emissions, which is fundamental in reducing the anthropic environmental impact.