European have public policies to reduce the greenhouse gas emissions, this Directive urged the member States to establish a 10% biofuel share in the motor fuel market by 2020. Its adoption led to the construction of many biodiesel plants in Spain; in 2010, there were 45, but one year later, only 31 plants were working at 25% of their production capacity. Nowadays, most of the current 44 production plants are at a standstill. This situation contrasts sharply with the growing consumption of biodiesel in Spain. The key issue is that most of the biodiesel consumed in Spain is imported, around 76% of the market share in 2012. Argentina is the largest supplier, providing almost half of the total consumed.
The aim of this study is to assess the direct and indirect environmental impacts to be expected if the demand of biodiesel in Spain increases to meet current European obligations. Two alternative pathways are compared under a consequential approach. The first pathway is in fact the prevailing one and consists of increasing the imports of soybean biodiesel from Argentina. The second pathway consists of increasing the production of biodiesel from used cooking oil. To reinforce the results, emphasis is placed on the uncertainty assessment, as it may influence decision-making.