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

Various Higher Education Institutions (HEI) set themselves goals to become carbon neutral through the implementation of different reduction strategies such as the replacement of fossil-fueled vehicles by electric cars. However, even if all reduction measures are taken, residual GHG emissions will still remain. Therefore, most HEIs have to compensate the remaining emissions for example by 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. In the current study, the CO2-footprint of the Hochschule Geisenheim University (HGU) as an exemplary HEI is assessed, hot-spots are identified and the utilization of biomass is investigated regarding the potential effect on the CO2 balance. The HGU main emissions are scope 1 emissions, which include direct emissions mainly caused by on-site heat supply. We found that the conversion to a woodchip-based heating system is not sufficient to achieve climate neutrality for HGU, but can be achieved by additional carbon dioxide removal (CDR). By operating a pyrolysis-based bivalent heating system, the heat demand can be covered and sufficient C-sink certificates can be produced to become the first carbon negative HEI at a comparable price to combustion systems. Surplus C-sink certificates can be made available to other authorities or ministries. As a result, 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: To remove CO2 from the atmosphere in order to limit global warming to as far below 2°C as possible at nearly no extra costs.