Consequential life cycle assessment of the environmental impacts of an increased rapemethylester (RME) production in Switzerland

Arable land is a constrained production factor – particular in Switzerland. Merely 45% of the consumed crops are produced domestically. Hence, the additional cultivation of rape for producing methyl ester is assumed to substitute crops used for food production. Consequently, Switzerland has to face the decision either to use the arable land for food production and import fuels or to produce fuel from rape and import the displaced food. Using Consequential Life Cycle Assessment (CLCA), the environmental consequences have been assessed if rape for energetic utilization substitutes rape used as edible oil or barley used as animal fodder. The study shows, that displacing food production by RME production in Switzerland can reduce total GHG emissions, when GHG-intense soy meal from Brazil is substituted by rape and sunflower meal, which is a co-product of the vegetable oil production. On the other hand, an increased production of vegetable oils increases various other environmental factors, because agricultural production of edible oil is associated with higher environmental impacts than the production and use of fossil fuels. In summary, the environmental impacts of an increased RME production in Switzerland rather depend on the environmental scores of the marginal replacement products on the world market, than on local production factors.