Bioenergy potential of agricultural and forest residues in Uganda

Biomass is the major source of energy in most developing countries. However, there are concerns about the sustainability of biomass supplies and the environmental impacts resulting from their use. Use of residues could contribute to ensuring sustainable supply of biomass energy. This study presents findings of an evaluation of the energy potential of agricultural and forest residues in Uganda using census data of the year 2008/2009. Annual productions of crop and forest residues were estimated using residue-to-product ratio (RPR) method. Energy potential of each residue class was then determined basing on their respective lower heating values. The biogas generation potential of each animal category was used to evaluate the energy potential of animal manure. Results showed that the total energy potential of the residues amount to 260 PJ y−1, which is about 70% of gross biomass energy requirement of Uganda for the year 2008. Crop residues had the highest contribution of about 150 PJ y−1, followed by animal residues with a potential of 65 PJ y−1. Maize residue is the predominant crop residue with energy potential of 65 PJ y−1 followed by beans and banana, each at 16 PJ y−1. This study indicates that agricultural and forest residues can be a major renewable energy source for Uganda. When sustainably utilised, biomass residues could contribute to reduction in environmental degradation in the country.