Enhancing biogas production using Organic Waste as Clean Energy for sustainable development

This study investigates the potential of kitchen waste sourced from five restaurants and traditional halls within Kwame Nkrumah University of Science and Technology (KNUST) for biogas production via anaerobic digestion for the first time. A total of 6,868 kg of waste, including cassava peels (39.7%), plantain peels (36.1%), and yam peels (24.2%), were collected over three weeks. Laboratory analysis assessed total solids (TSs), volatile solids (VSs), and ash content of representative waste samples. The TS values ranged from 14.82% to 35.26%, while VS values, indicative of biodegradable potential, spanned 53.3% to 83.7%, confirming high methane yield potential. Ash content remained below 10%, reinforcing the organic-rich composition.

Biogas yield was measured per kilogram of feedstock, with cassava and plantain peels yielding an average of 0.45–0.52 m³ CH₄/kg, outperforming yields reported in similar Ghanaian municipal waste studies by over 20%. Compared to traditional reliance on livestock manure with typical methane yields of 0.20–0.30 m³ CH₄/kg, the kitchen waste feedstock demonstrated superior energy conversion efficiency.

This research concludes that kitchen waste in high-density institutional environments provides a sustainable and efficient substrate for decentralized biogas generation, aligning with circular economy models. By diverting organic waste from landfills and reducing methane emissions, this method offers an affordable and environmentally sound solution to campus energy and sanitation challenges. The findings support broader integration of kitchen-waste-based digesters in urban institutions, with potential replication across West Africa to improve waste valorization and reduce reliance on fossil fuels.