Environmental aspects of sustainability

Renewable fuels require sustainability certification in order to count towards the national GHG reduction quota as well as towards the minimum renewable energy share required by the EU. The following figure shows the GHG emissions of the commercially available renewable fuel options in road transport for which counting on the GHG quota in 2020 has been claimed. The values are therefore from fuels that have received a sustainability certificate. In addition, the figure also shows the default values for commercially available renewable jet fuels from the ISCC-CORSIA system document. For the GHG emissions from the use of electricity, the GHG values of the German electricity mix are shown on the one hand, and the GHG value from wind offshore, wind onshore and photovoltaic electricity generation on the other. The GHG emissions only refer to the energy content of the fuel. The use in the different types of engine systems is not taken into account. In addition, the minimum GHG savings for biofuels in road transport compared to the fossil benchmark of 83.8 g CO₂ eq./MJ from the RED valid in 2020 of 50 % and 60 %, respectively, are shown. The GHG saving requirement for sustainable aviation fuels of 10 % compared to the fossil benchmark of 89 g CO₂ eq./MJ from the ISCC-CORSIA certification scheme is also plotted.

In the overall comparison of commercially available renewable energy sources, the use of electricity from renewable sources, such as wind power for electric mobility, is associated with the lowest GHG emissions. Using the electricity generation mix instead of pure renewable electricity, however, emits the most GHG emissions. A comparison of the GHG emissions of biofuels in road transport shows that biomethane as CNG has the lowest GHG emissions ahead of bioethanol and ahead of biomethane as LNG, which is also due to the high share of residual and waste-based raw materials. FAME has medium GHG emissions in total. The highest GHG emissions are achieved by HVO, vegetable oils and the new biomethanol included in the quota. However, all commercially available biofuels in road transport fulfil the required minimum GHG reductions - otherwise they should not have been counted towards the GHG quota. The lowest GHG emissions among biofuels in 2020 were achieved by biomethane from residues and waste, bioethanol from maize and sugar cane, and FAME from used cooking oils and fats (UCO).

The presented standard GHG emissions of HEFA aviation fuels are also shown there. However, they cannot be compared with the actual GHG emissions of biofuels from road transport, as they represent generic average values. Within these default values of the biokerosines, however, it is also clear that the residue- and waste-based kerosines have potentially lower GHG emissions than the cultivated biomass-based kerosines. All HEFA aviation fuels can achieve the required GHG savings of the ISCC-CORSIA certification system with their default values.