Greenhouse Gas Emissions
RWTH's energy data management is currently being expanded and further measures are being taken to record and process our energy data more systematically in the future. The aim is to obtain more reliable and valid data for RWTH, particularly with regard to energy consumption. In addition, RWTH will in future report comprehensively in the context of the 'Klimaneutrale Landesverwaltung NRW (KNLV)'/ ,Climate Neutral State Administration NRW' initiative using the balancing tool provided by the Landesamt für Natur, Umwelt und Verbraucherschutz NRW (LANUV)/ ,State Office for Nature, Environment and Consumer Protection NRW'.
As some of the data published to date has been calculated on the basis of estimated values at relevant points and is subject to a number of conditions, we have decided not to publish the data again until the systematic collection and processing of the energy data has been completed in order to ensure consistency with future information and to avoid any misunderstandings when comparing the values.
Emissions From Business Trips
The emissions reported for business trips relate to air travel as well as business trips by car and public transport. The basis for calculating the emissions data for business air travel is provided by the University’s contract travel agencies. For 2022, the emissions from business trips were calculated using the greenhouse gas balancing tool described below, analogous to the RWTH’s first Sustainability Report, and therefore without taking into account pandemic-related influences on specific emissions with a view to reduced passenger numbers in public transport (air travel). It should also be noted that business trips by rail are assessed as being climate neutral. According to the information provided by Deutsche Bahn, direct emissions are avoided through the use of renewable energies when traveling with bahn.business. Indirect emissions and diesel-related emissions from local transportation are offset. This applies to both reporting years 2021 and 2022. Nevertheless, the emissions calculated for business trips show a renewed upward trend, even if the emission values for 2022 are below those of the pre-COVID period. Any long-lasting, verified effects on the travel behavior of university members will probably only be seen in the future. Please also read “Business trips and climate fund” in the Mobility section of this report.
Operation of the Combined Heat and Power Plants
The natural gas requirement for the operation of the three combined heat and power plants rose from 2020 (91,449 MWh) to 2021 (100,137 MWh) and fell again in 2022 to 94,908 MWh, partly due to the natural gas crisis in the fall of the same year. The natural gas crisis also explains the sharp increase in the purchase of heating oil EL to 2,999 MWh for 2022 compared to 180 MWh in the previous year. The background to this is to secure the supply of the heating plant by using heating oil as a substitute for natural gas.
The University’s own Melaten combined heat and power plant is one of the facilities subject to emissions trading. RWTH Aachen University is therefore obliged to surrender certificates to the German Emissions Trading Authority (DEHSt) in accordance with the CO2 emissions generated here. The surrender of certificates shows a noticeable downward trend (see figure, 1 certificate corresponds to 1t CO2). In addition, the noticeable change from 2021 to 2022 is mainly due to the decoupling of Uniklinik RWTH Aachen from the RWTH’s heat supply.
The emission certificates shown in the figure only take into account the CO2 emissions at the Melaten CHP plant site in accordance with the German Greenhouse Gas Emissions Trading Act (TEHG), including all emissions for natural gas and heating oil used there. They also include the provision of heat for associated facilities.