Quantification and characterization of cocoa pod husks for electricity generation in Uganda.

Abstract

Background: Due to limited coverage, the electricity power supply in Uganda is an obstacle to the country’s economic development. Utility firms in Uganda either lack the financial capacity to expand their grids to isolated rural areas or choose not to do so due to the low return on investment. Therefore, connecting households to minigrids represents an effective solution to providing power to remote/rural areas. This study evaluates the resource and technology of generating electrical energy from cocoa pod husks (CPHs), an agricultural residue/waste, generated in Uganda. The use of agricultural waste for energy generation is the most suitable option for the rural population in Uganda because of the availability of a raw material (biomass) for its production, which is pollutionfree (renewable and clean) and does not have competition for use. The inability to convert these solid wastes into useful products culminates into environmental related challenges, such as landfilling, climate change, pests, and diseases. Therefore, the aim of this study is to quantify the amount of generated CPHs and evaluate its potential for electricity generation in Uganda. Subsequently, we have been looking into the potential of CPHs as a feedstock for a thermochemical conversion process and the feasibility of a direct combustion technology. Results: The amount of CPHs generated in Uganda has been estimated. The physiochemical analysis has shown that the proportion of CPHs in the fresh pods is about 74%, which is nearly the same as in other studies. The dry matter content of CPHs has been found to be on an average of 19%, whereas ash content, moisture content, and the gross caloric value have been recorded to be 12.3%, 12.58%, and 17.5%, respectively. It seems therefore likely that 41.7 GJ of energy might be produced each year from CPHs in Uganda. Conclusion: This study has demonstrated that the CPHs are an important energy source. As there is an increasing trend in cocoa and CPH production in Uganda per year, the electricity production based on CPHs is sustainable and can be upgraded. The use of CPHs for energy conversion is therefore feasible, cost-efficient, and a solution to some environmental challenges. Keywords: Cocoa pod husks, Electricity generation, Biomass, Uganda