Modelling crop productivity in biofuel development plans: A study in the Cerrado (Brazil)

Biofuels production have important impacts on local environment and land use. It is thus necessary to develop bioenergy exploitation plans in order to maximize their potentiality, keeping at the same time under control all the other issues that may be of relevance. The area considered in this work lies within a particular Brazilian Region called Cerrado. The Brazilian Biodiesel Development Plan suggests traditional soybean plantations in the Cerrado should be substituted with other oleaginous crops, such as castor. The effectiveness of such a plan can be analyzed by solving a mathematical programming problem that maximizes the energy output from oleaginous crops. Results strongly depend on the assumed productivity of castor. On the other hand, energy production is less sensitive to such a parameter. Indeed, crop productivity is better described as a stochastic variable, since it depends not only on the climatic conditions, but also on market evolution and on the improvement of the cultivation techniques. Aim of this work is to illustrate a method to deal with such a variability of the crop productivity within a bioenergy plan and to determine how much it may affect the energy balance and other issues like biodiversity, land use and greenhouse gases balance.