• Energy Research
• Closed Access close

Abstract Biomass is a renewable energy resource; however, its exploitation raises concerns about its ability to sustain the growing demand and its negative impacts on the environment, particularly in developing countries. These concerns are more prominent on the African continent where high population growth rates is leading to high rates of deforestation due to expansion of agricultural land and increased demand for bioenergy. Use of traditional and inefficient bioenergy technologies and appliances also exacerbate the problem. This paper presents a review of the efforts and progress made by different organisations in promoting improved bioenergy technologies in Uganda. The study was based on an extensive review of available literature on improved bioenergy technologies introduced in the country. It was found that there is high level of wastage of biomass resources since an estimated 72.7% of the population use traditional cooking stoves with efficiency estimated to be less than 10%. Inefficient cooking stoves are also blamed for indoor air pollution and respiratory illness reported amongst its users. Modern bioenergy technologies such as biomass gasification, cogeneration, biogas generation, biomass densification, and energy-efficient cooking stoves have been introduced in the country but have certainly not been widely disseminated. The country should pursue policies that will accelerate proliferation of more efficient bioenergy technologies in order to reduce the negative environmental impacts of bioenergy utilisation and to ensure sustainability of biomass supplies.

Abstract Biomass is a renewable energy resource; however, its exploitation raises concerns about its ability to sustain the growing demand and its negative impacts on the environment, particularly in developing countries. These concerns are more prominent on the African continent where high population growth rates is leading to high rates of deforestation due to expansion of agricultural land and increased demand for bioenergy. Use of traditional and inefficient bioenergy technologies and appliances also exacerbate the problem. This paper presents a review of the efforts and progress made by different organisations in promoting improved bioenergy technologies in Uganda. The study was based on an extensive review of available literature on improved bioenergy technologies introduced in the country. It was found that there is high level of wastage of biomass resources since an estimated 72.7% of the population use traditional cooking stoves with efficiency estimated to be less than 10%. Inefficient cooking stoves are also blamed for indoor air pollution and respiratory illness reported amongst its users. Modern bioenergy technologies such as biomass gasification, cogeneration, biogas generation, biomass densification, and energy-efficient cooking stoves have been introduced in the country but have certainly not been widely disseminated. The country should pursue policies that will accelerate proliferation of more efficient bioenergy technologies in order to reduce the negative environmental impacts of bioenergy utilisation and to ensure sustainability of biomass supplies.

Abstract 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.

Abstract 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.

This study employed the Life Cycle Assessment (LCA) methodology to evaluate the environmental impacts of utilizing cattle manure as a substrate for biogas generation for cooking energy in Uganda. Results of the study showed that biogas energy systems based of cattle manure has potential environmental benefits in comparison to charcoal produced from natural forests. Under baseline scenario, without recycling of slurry as fertilizer, the biogas system leads to total environmental impacts of over 80% less than that of charcoal system. When slurry is utilized as substitute mineral fertilizers, the environmental impact of biogas system was found to be less than that of charcoal by close to 95%. The study further showed that that use of biogas could lead to considerable reduction on human health impacts compared to charcoal. In conclusion, utilization of cattle manure for biogas production has potential benefit of reducing the environmental impacts due to charcoal production and use in Uganda.

This study employed the Life Cycle Assessment (LCA) methodology to evaluate the environmental impacts of utilizing cattle manure as a substrate for biogas generation for cooking energy in Uganda. Results of the study showed that biogas energy systems based of cattle manure has potential environmental benefits in comparison to charcoal produced from natural forests. Under baseline scenario, without recycling of slurry as fertilizer, the biogas system leads to total environmental impacts of over 80% less than that of charcoal system. When slurry is utilized as substitute mineral fertilizers, the environmental impact of biogas system was found to be less than that of charcoal by close to 95%. The study further showed that that use of biogas could lead to considerable reduction on human health impacts compared to charcoal. In conclusion, utilization of cattle manure for biogas production has potential benefit of reducing the environmental impacts due to charcoal production and use in Uganda.