Abstract:
Mini-grids connecting households to a generator can be a solution for providing rural communities in developing
countries with electricity. Substituting diesel with locally produced Jatropha oil can improve economic
and environmental sustainability of rural electrification. Jatropha is known as a labor intensive crop, but little
is known about how inclusion of human energy input will affect the energy balance of production of Jatropha
oil. In this study we investigate human labor requirements in rural electrification with Jatropha oil. Jatropha
in this study in Tanzania was grown as living fences and provided multiple benefits. An energy flow chart of
generation of electricity from Jatropha oil is presented, and it is shown that human energy expenditure in
production of Jatropha oil is small relative to the overall energy in the system. Time consumption however
is extensive, and 7.5 hour work is required to harvest and de-hull Jatropha fruit equivalent to 1 kg Jatropha
oil. 1 kg Jatropha oil can in turn provide the community with 2.5 kWh electricity through a Multi Functional
Platform connected to a local grid. Potential income from harvesting Jatropha is considered so low in the
study area that farmers are reluctant to venture into it. Poorer people and children in the community are
allowed by the farmers to harvest for free. Collection of seeds for Jatropha oil depends on the availability of
labor willing to work for an income of approximately 0.9 USD/day. Social and economic sustainability of
rural electrification based on Jatropha oil can be enhanced through generous subsidy.