Abstract:

To be a viable alternative to fossil fuel,biofuel should yield a positive energy balance,have contribution to environmental improvement,be economically feasible,and be producible in large quantities without impacting food security.As a major feedstock of the secondgeneration biodiesel,〖WTBX〗Jatropha curcas〖WTBZ〗 L.(JCL)has been widely developed in China, but its viability for substituting fossil biodiesel has not been systematically assessed.This paper analyzed the economic,environmental and energy performance of the production and use of JCL oil through life cycle analysis.The results show that:(1)at the current levels of seed yield,technologies and management,the production and use JCL oil is financially infeasible,and for the industrialization of JCL oil,producers should be subsidized with an amount of 8817～1 4381Yuan/hm2 for seed production and 268Yuan/L for oil extraction and refining;(2)about 13 kg CO2 equivalent can be reduced as per liter JCL oil is produced;(3) the energy efficiency depends on the seed yields.If JCL oil is considered the only energy output,there is energy efficiency when the seed yield is higher than 795 kg/hm2.If the biomass other than seeds is considered the energy output,there is also significant energy efficiency when the seed yield is as low as 297 kg/hm2.The results of sensitivity analysis show that increasing the seed yield can reduce the unit cost of JCL oil but result in a decreased financial net present value,because the unit cost of JCL is higher than the unit price of diesel in the market.However,the environmental benefits and energy efficiency tend to increase as the JCL seed yield is increased.Finally,based on the results of the study,some measures were suggested to improve the lifecycle economic,environmental and energy performance.