Multi-criteria sustainability assessment of the of cooking energy systems in Uganda

The need to provide clean and reliable energy for cooking that is compatible with socio-economic status of the population, technologically appropriate and environmentally friendly is a major challenge to sustainable development in developing countries. Efforts to simultaneously fulfil the social, economic, environmental and technological objectives of systems are hampered by conflicting nature of the objectives. The multi-criteria decision methods are suitable for solving such conflicting decisions. In this study, we proposed a multi-criteria decision analysis method that attempts to incorporate all these conflicting objectives to make more sustainable choices of cooking energy systems in a developing country. The method involves selection and quantification social, economic, environmental and technological criteria and incorporating them in a decision making framework using Preference Ranking and Organisational Method for Enrichment Evaluation (PROMETHEE) and Graphical Analysis for Interactive Aid (GAIA) methods. The framework was used in a case study to aid the decision choice between domestic biogas system and traditional charcoal system in Uganda. Impacts on human health and climate change impacts were used as environmental criteria and determined using Life Cycle Analysis (LCA). Efficiency and maintainability of combustion appliances were used as technical criteria, while economic criteria were based on capital and operating costs. Job creation and acceptability comprised the social criteria. Results showed that the biogas system is more competitive than charcoal under both the PROMETHEE I partial ranking and the PROMETHEE II complete ranking. However, the major challenges of biogas systems were the high capital costs and impact on human health attributed to use of chemical fertilizers in grass feed production. In an alternative scenario with increased recycling of slurry as substitute to chemical fertilizers, the performance of the biogas systems showed improvement. In both scenarios, the main challenges of the charcoal system were the high operating costs, climate change impacts and inability to create formal jobs. The study therefore suggests that biogas is a more sustainable household cooking energy than charcoal in Uganda, but still faces the challenge of high capital costs