Rapeseed biodiesel and climate change mitigation in the EU

Abstract: Under the Kyoto protocol the European Union (EU) has committed itself to reducing its greenhouse gas emissions to 92% of 1990 levels. Carbon sequestered in agriculture is allowed to be countered against emissions to help meet the targets. Biofuels represent an infinite possibility to sequester carbon in agriculture, as they reduce emissions by replacing fossil fuels. The EU has set the target that all transport fuels consumed in member states should contain 5,75% biofuels. Biodiesel made from rapeseed oil is found to reduce emissions by 50-75% when the full system of production, transport and consumption is considered. However, there is much uncertainty about the scale of emissions of nitrous oxide from the soil under the oilseed rape fuel crop. Emissions of nitrous oxide tend to increase when fertiliser is applied. Fuel crops can be grown on set-aside agricultural land which is not presently fertilised. This is likely to cause increased emissions of nitrous oxide due to the increased fertiliser application. However, it is not realistic that the raw materials needed to meet the 5,75% target can be supplied from set-aside land alone. It will be necessary either to reduce the areas under other crops or to expand the area of arable land in the EU. But such an expansion of arable land may result in soil emissions of a magnitude per litre biodiesel similar to the full emissions of an equivalent quantity of fossil diesel. In this scenario biodiesel is not an aid in reducing greenhouse gas emissions.