Effect of farming system and yield in the life cycle assessment of Jatropha-based bioenergy in Mali

Jatropha has been promoted in sub-Saharan Africa as a smallholder energy crop promising additional revenue and energetic self-sufficiency. In this case-study located in Southern Mali we performed a comparative life cycle assessment shedding light on the influence of smallholder participation and yield fluctuations on the global warming potential, fossil resource depletion and energy demand of jatropha-based rural electrification in comparison to a fossil fuel-based reference. We found that the global warming potential of jatropha-based electrification can be 13% higher to 20% lower than fossil diesel, depending on the yield. In terms of energy use and fossil fuel depletion, jatropha is more favourable than fossil-based electricity. In either perspective, the activities related to cultivating and processing grain from small farmers accentuate the environmental impacts, owing to low yields. We conclude that outgrower engagement in tending and harvesting jatropha is a key factor for improving the environmental performance of the system. (C) 2014 International Energy Initiative. Published by Elsevier Inc. All rights reserved.