Uncertainties about the GHG Emissions Saving of Rapeseed Biodiesel

During the last years, the renewable energy strategy of the European Union (EU) and the proposed policies and regulations, namely the Renewable Energy Directive (RED), have been heavily discussed among scientific circles and various interest groups. The sustainability of different biofuels and their contribution to the reduction of greenhouse gas (GHG) emissions and the whole renewable strategy has become one of the most controversial issues. RED requires that the greenhouse gas emissions associated with production and use of biofuels are at least 35% lower than those associated with the production and use of conventional fuels to be classified as 'sustainable' and therefore eligible for the mandatory blending scheme applied within the EU. In a recent working paper, we analyze the GHG emissions savings potential of rapeseed biodiesel. For this purpose, we ran a life cycle assessment of rapeseed biodiesel using the same basic methodology and background data contained in RED by considering the whole production chain from cultivation of the feedstock up to use of the biofuels. Unlike other studies, we refer only to publicly available and published data in our calculations. In order to ensure full transparency - again contrary to the vast majority of other studies - we provide a detailed documentation of all data. We follow a rather conservative approach by using average values and assuming common conditions along the supply chain in our scenarios. In most of the scenarios, rapeseed biodiesel does not reach the GHG emissions saving values using the formula contained in RED. Neither the RED typical value for rapeseed oil (45%) nor even the lower default value (38%) can be supported by the analysis. Furthermore, most of the scenarios indicate that rapeseed biodiesel does not reach the 35% threshold required by the EU Directive for being considered as sustainable biofuel. In the standard scenario, we calculate a GHG emissions saving value of not even 30% which is not only well below the GHG emissions saving values (default and typical) that can be found in RED but also far below the 35% threshold. To summarize, we are not able to reproduce the GHG emissions saving values published in the annex of RED. Therefore, the GHG emissions saving values of rapeseed biodiesel stated by the EU are more than questionable. Given these striking differences as well as the lack of transparency in the EU's calculations, we assume that the EU seems to prefer 'politically' achieved typical and default values regarding rapeseed biodiesel over scientifically proven ones.

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