Profitability analysis of developed briquette suitable for energy generation from residue of cattle feed sorghum stalk and groundnut husk

Abstract The increasing demand for clean and affordable energy in developing countries highlights the need to utilize abundant agricultural residues through sustainable technologies. This study investigates the production, optimization, and economic feasibility of biomass briquettes developed from sorghum stalks and groundnut husks using cow dung as a natural binder. Response Surface Methodology (RSM) was applied to evaluate the effects of particle size, binder proportion, and feedstock mixing ratio on key fuel properties, including density, shatter index, and calorific value. The optimized composite briquette exhibited a calorific value of 24.36 MJ·kg⁻1, density of 1.202 g·cm⁻3, and shatter index of 96.19%, outperforming single-feedstock briquettes. Proximate analysis revealed low moisture (3.16%), low ash (3.63%), and high volatile matter (≈80%), while ultimate analysis indicated favorable elemental composition with 51.56% carbon, 6.30% hydrogen, and negligible nitrogen and sulfur, suggesting low emission potential. Economic evaluation demonstrated strong investment viability, with a positive Net Present Value (NPV), a payback period of 2.25 years, and profitable break-even capacity under typical local market conditions. Overall, the findings confirm that sorghum stalk and groundnut husk residues can be efficiently converted into high-quality briquettes with promising economic returns, offering a sustainable alternative to traditional biomass fuels and contributing to improved energy security and environmental conservation in Ethiopia.