A multicriteria decision analysis for the selection and ranking of crop residue for sustainable energy generation in West Africa

• MCDA is employed to identify optimal crop residue for efficient bioenergy production. • Straw residue emerged as the optimal feedstock. • West Africa possesses 402 million metric tons of valuable residual biomass. • Staple crops like cassava and maize are major biomass contributors. • Agricultural residue holds a substantial electricity potential of around 170 TWh. West Africa faces significant energy access challenges, particularly in rural areas, where limited energy supply exacerbates poverty and insecurity. Renewable energy from agricultural residues has emerged as a promising solution to address energy shortages and climate change. However, while 18 African countries, including Mauritius, utilize agricultural residues such as sugarcane bagasse for electricity generation, West African nations remain underdeveloped in this area. This study explores the potential of using alternative crop residues to alleviate energy stress and poverty in the region. Given the complexities of factors such as availability, moisture content, and energy content in crop selection, multicriteria decision analysis (MCDA) was employed to identify the most suitable crop residues for bioenergy production in West Africa. Expert consultations were conducted to define assessment criteria and evaluate various residues, including straws, peels, husks and shells, fibers, and stalks. The findings indicate that straw residues, particularly from cereals, are the most suitable for energy production, followed by husks and shells, stalks, fibers, and peels. The study estimates that West Africa could annually harvest approximately 402 million metric tons (Mt) of biomass, with an energy content of 6,960 Petajoules (PJ). Key crops such as cassava, maize, rice, and sorghum contribute significantly to this biomass potential, with cassava accounting for 35% of the total energy. Nigeria and Ghana emerge as the leading countries in terms of energy potential. The techno-economic assessment for 2021 estimates that 614 PJ, equivalent to 170 Terawatt hours (TWh), could be realized. With total energy consumption in West Africa reaching 3.05 EJ (3050 PJ) in 2022, agricultural residues alone could meet approximately 20.13% of the region's total energy demand. This research underscores the importance of strategic crop residue selection and biomass utilization as a key driver for sustainable energy production, offering a viable solution to energy poverty and fostering the adoption of renewable energy in West Africa.