Additional supporting evidence for significant iLUC emissions of oilseed rape biodiesel production in the EU based on causal descriptive modeling approach

摘要

Agro-economic modeling studies have shown that indirect land-use change (iLUC) emissions of first-generation biofuels can be significant, reducing or eliminating the climate change mitigating potential of these fuels. Recognizing this, proposed amendments to the European Union's Renewable Energy Directive (RED) would require reporting iLUC emissions of biofuels. The objective of this paper was to provide additional evidence of the iLUC emissions of oilseed rape (OSR) biodiesel using a noneconomic modeling approach called the causal descriptive (CD) model. The CD model originally developed by E4tech (A Causal Descriptive Approach to Modelling the GHG Emissions Associated with the Indirect Land Use Impacts of Biofuels, 2010, E4tech, London, UK) is one of the first noneconomic modeling approaches used for estimating indirect land-use change (iLUC). Using the E4tech CD modeling framework, we refine assumptions for key parameters such as yields in marginal land, displacement of OSR oil by palm oil, land availability for OSR expansion in the EU, imports of OSR from Canada and Ukraine, and palm oil expansion on peatland and thereby estimate iLUC GHG emissions for a likely scenario (Central Scenario). We find GHG emissions of OSR biodiesel to be 57?g COsub2/sub eq./MJ for the Central Scenario. To capture the possible range of iLUC GHG emissions, we calculate iLUC GHG emissions by changing assumptions for the Central Scenario and land-use emission factors. We find that GHG emissions of OSR biodiesel may vary from 18 to 101 COsub2/sub eq./MJ. The results provide additional evidence supporting the previous conclusions derived from agro-economic modeling studies that iLUC emissions of food-based biofuels can be expected to be significant compared to potential savings. Hence, to achieve meaningful GHG reductions from biofuel use and avoid policy failure, it is important that the EU should take concrete policy action to target support for biofuels toward those with the lowest expected iLUC emissions.