Zvinavashe E.,A and F Biobased Products |
Elbersen H.W.,A and F Biobased Products |
Slingerland M.,A and F Biobased Products |
Kolijn S.,A and F Biobased Products |
Sanders J.P.M.,A and F Biobased Products
Biofuels, Bioproducts and Biorefining | Year: 2011
As in most of sub-Sahara Africa, rural people in Mozambique use firewood as their main source of energy. The use of firewood is associated with several health problems, and the time spent collecting it reduces time for other activities. Cassava is grown as a reserve crop in Mozambique where it is considered a 'woman's crop'. Because the crop is drought-tolerant and resistant to diseases, it needs little attention and hence little labor input. This paper examines how the rural people in the case of Mozambique can use their current reserve crop, cassava, to meet their energy needs and food requirements and to increase their annual income. Cassava processing chains were modeled to assess (i) the effect of introducing an anaerobic digester for the digestion of cassava peels and other material (dung, kitchen waste and maize residues) at family level (BAU (business as usual) + family digester) and (ii) the effect of introducing an ethanol plant with treatment of stillage and production of electricity (BAU + community ethanol). The results show that it is economically viable to have BAU + family digester system and BAU + community ethanol. Sensitivity analysis showed that an increase in crop yield and the local price of cassava are the most important factors to increase the economic viability of the BAU + family digester system. Sensitivity analysis of the BAU + community ethanol system showed that this system is mainly affected by the price of ethanol. Besides the economic benefits, the proposed systems have other benefits, such as efficient recycling of nutrients and pollution reduction. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd.