World biofuel production and trade have grown exponentially in the last decade. Nevertheless, the interaction between the markets for oilseeds (food/feed/bioenergy) and liquid vegetable oil-based biofuels is overwhelmingly complex and thus not well understood. In this study, we developed a spatially explicit agent-based model to provide insights into the effect of farmers' behaviour on trade flows and biodiesel production and to shed light on the influence of import tariffs for both palm oil and biodiesel on system behaviour. This new approach enables us to assess different types of rational economic behaviour for the adoption of crops by farmers. Results show that model outcomes can vary substantially based on the assumptions made concerning the behaviour of farmers. Moreover, we found that biodiesel trade and production are more sensitive to a change in the EU-28's biodiesel import tariff than to a change in the EU-28's palm oil import tariff. Overall, our results show that social processes, actors' heterogeneity, and institutions play an important role in the behaviour of the system.

Biofuel production is not cost competitive and thus requires governmental intervention. The effect of the institutional framework on the development of the biofuel sector is not yet well understood. This paper aims to analyze how biofuel production and production capacity could have evolved in Germany in the period 1992–2014. The effects of an agricultural policy intervention (liberalization of the agricultural market) and a bioenergy policy intervention (a tax on biodiesel after an initial exemption) are explored. Elements of the Modeling Agent systems based on Institutional Analysis (MAIA) framework, complex adaptive systems (CAS) theory, and Neo Institutional Economics (NIE) theory were used to conceptualize and formalize the system in an agent-based model. It was found that an early liberalization of the agricultural market led to an under-production of biodiesel; a late liberalization led to the collapse of biodiesel production. An early introduction of the biodiesel tax led to stagnation in biodiesel production and production capacity; a late introduction led to an increase in sunk costs provided that the biofuel quota is binding. Also, a lack of agents’ adaptation mechanism to forecast prices led to a decrease in patterns of biodiesel production when an external shock was introduced in the system. In sum, we argue that system behavior is influenced by individual behavior which is shaped by institutions.