Energy and greenhouse gas balances of biofuels from Jatropha curcas

In recent years, Jatropha curcas, a perennial, inedible crop well adapted to semi arid regions, has received much interest as a new alternative for biofuel production, minimizing adverse effects on the environment and food supply. Nevertheless, production of J. Curcas needs different inputs, such as fertilisers or pesticides, which cause environmental impacts. Thus, life-cycle assessment has been performed to quantify the benefits of J.curcas biofuel production in West Africa, compared with fossil diesel fuel. LCA analyses environmental impacts all along the biodiesel from J. Curcas production chain, namely field cultivation, seed harvest, seed transportation, cold press, oil transportation, oil refining, transesterification and finally biodiesel distribution. Results are based on experimental data from J. Curcas cultivation under Mali conditions. As for other fuels, standard conditions of production are considered. Combustion of different fuels into vehicles is not included. To compare all different fuel productions, functional unit is defined as the production of 1 MJ of biodiesel from J. Curcas or conventional gasoline diesel lower heating value. Impact categories under consideration are global warming and fossil energy use. Biodiesel from J.curcas has a much higher performance than current biofuels, relative to oil-derived diesel fuels. Under West Africa conditions, J.curcas biodiesel allows a 72% saving in green house gas emissions compared with conventional diesel fuel, and its energy yield (the ratio of biodiesel energy output to fossil energy input) is 4.7. J. curcas production studied is eco-compatible for the impacts under consideration and fits into the context of sustainable development