Purpose <p>This study evaluates the environmental and financial impact<b>s</b> of anaerobic digestion (AD) on pig farms in Extremadura, Spain. It compares two scenarios: mono-digestion of pig slurry and co-digestion using pepper waste from a nearby vegetable processing plant. The goal is to assess the advantages of co-digestion in terms of energy production, economic benefits, and environmental performance.</p> Methods <p>A prospective life cycle assessment (pLCA) was conducted, including an up-scaling to account for real-world conditions. The functional unit was defined as the amount of waste treated per year. The study considered the full system, including transportation of vegetable waste, on-site anaerobic digestion, and biogas utilization in a combined heat and power (CHP) unit. A Monte Carlo simulation was applied to assess the impact of electricity price volatility on Net Present Value (NPV) and Internal Rate of Return (IRR).</p> Results <p>The findings show that co-digestion produces 70% more electricity and offers 5.5 times higher economic benefits compared to mono-digestion. In most categories, co-digestion shows 2 to 4 times higher benefits per tonne treated, 1.5 times higher per euro earned, and better waste management capacity. The <b>c</b>ogeneration process of AD results in impacts at least 1.5 times lower than the energy required for farm operations.</p> Conclusion <p>Co-digestion proves to be a more economically and environmentally advantageous option than mono-digestion. The results highlight the potential of expanding AD facilities as a sustainable and efficient solution to improve energy self-sufficiency and optimize waste management in pig farming.</p> Graphical Abstract <p></p>