Exploring New Alternative Energy for Sustainable Food Production

The growing demand for energy and food, driven by global population growth, requires innovative solutions to ensure food and energy security. Despite technical and economic challenges, biodigesters are emerging as promising decentralized technologies for producing energy and nutrients from biomass. This study investigated the use of biodigesters to produce biogas and biofertilizers through the co-digestion of poultry litter (animal waste) with new biomass alternatives (sweet potato and cassava), evaluating the value of the bio-inputs generated by adding energy crops in the digestion process. Three treatments were defined to analyze the potential for biogas and macronutrient production, along with thirty scenarios for economic analysis based on deterministic and stochastic methods. Results showed that co-digestion significantly outperformed mono-digestion. Cassava generated 17.48% more biogas and reduced volatile solids by 16.39%, while sweet potato improved by 12.65% and 15.48%, respectively. No significant differences were found in biogas potential or methane content between treatments, sweet potato yielded 0.449 m³ kg⁻¹SVadded and 61.92% methane, and cassava 0.457 m³ kg⁻¹SVadded and 61.79% methane. Nitrogen, phosphorus, and potassium concentrations averaged 1.24%, 3.09%, and 3.11% between treatments, with no significant variation. Co-digestion could increase profits by up to 60%, compared to the opportunity cost of selling poultry waste. Stochastic analysis showed that over 50% of scenarios could result in net present values positive. Incorporating sweet potato and cassava in the process enhances internal rates of return across production scales. These findings offer a path to reducing environmental impacts while promoting economic growth in poultry production systems.