Escalating global energy crisis coupled with pressing environmental concerns has accelerated the transition towards sustainable, eco-friendly and economically viable energy sources. This study evaluated the potentials of sweet potato peels, a widely available agricultural residue as a substrate for biogas generation using a laboratory scale batch anaerobic digester under mesophillic conditions. Prior to digestion, the substrate was pre-treated and co-digested with cow dung at a 1:2 ratio over a 25-day retention period, to enhance microbial activity and process stability. Biogas yield, pH and temperature were recorded daily to assess digester performance. To improve the biogas quality, the raw biogas was up graded through sequential treatment using an iron sponge for H2S removal and water scrubbing for CO2 removal. Gas production commenced within 48 hours, indicating quick substrate degradability. Comparative biogas analysis before and after purification revealed a substantial enrichment in methane content from 57.21 % to 84.32%, CO2 and H2S were significantly reduced from 30.2% to 1.9% and from 1,93ppm to 0.04ppm respectively. These findings demonstrate that pretreated sweet potato peels co-digested with cow dung can deliver high quality biogas within a relatively short retention time, supporting their viability as a sustainable energy feedstock. The purification process effectively removed noncombustible and toxic constituents, thereby enhancing its quality. Trace contaminants including carbon monoxide (0.03 ppm), nitrogen oxides (NO = 1.36 ppm, NO₂ = 0.82 ppm, NOx = 2.18 ppm), and volatile organic compounds (8.55 ppm), were present at minimal concentrations that can be useful for domestic use. The slight elevated oxygen level detected was attributed to sampling contamination and did not compromise the methane concentration. Collectively the results confirmed that sweet potato peels are viable substrate for biogas production and upgrading the biogas further increase the methane content to level suitable for domestic and small-scale applications. These findings suggest that sweet potato peels can serve as a sustainable waste to energy resource for decentralized biogas systems for rural energy security, sustainability and waste management