Transitioning Hochschule Geisenheim University: A Shift from NET Source to NET Sink Regarding Its CO2 Emissions

Various Higher Education Institutions (HEIs) set themselves goals to become carbon neutral through the implementation of different reduction strategies such as the replacement of fossil-fueled vehicles with electric cars. However, even if all reduction measures are taken, residual GHG emissions will still remain. Therefore, most HEIs have to compensate for the remaining emissions by, for example, buying carbon credits. However, due to growing criticism of carbon credit purchases, HEIs need to explore options for establishing carbon sinks on their own premises to offset their remaining, unavoidable emissions. This study aimed to assess the CO2 footprint of Hochschule Geisenheim University (HGU) as an exemplary HEI, identify emission hot-spots, and investigate the potential of biomass utilization for achieving carbon neutrality or even negative emissions. The analysis found that HGU’s main emissions were scope 1 emissions, primarily caused by on-site heat supply. The research determined that conversion to a wood chip-based heating system alone was insufficient to achieve climate neutrality, but this goal could be achieved through additional carbon dioxide removal (CDR). By operating a pyrolysis-based bivalent heating system, the study demonstrated that heat demand could be covered while producing sufficient C-sink certificates to transform HGU into the first carbon-negative HEI, at a comparable price to conventional combustion systems. Surplus C-sink certificates could be made available to other authorities or ministries. The results showed that bivalent heating systems can play an important role in HEI transitions to CO2 neutrality by contributing significantly to the most urgent challenge of the coming decades: removing CO2 from the atmosphere to limit global warming to as far below 2 °C as possible at nearly no extra costs.