Analysis of Environmental and Economic Benefits of Co-Digestion Based on Life Cycle Assessment : a Comparison Between Co-digestion, Anaerobic Digestion and Waste Water Treatment Plant

This study examines the economic viability and environmental benefits of co-digestion technology in biogas production, using Sweden’s NSR Biogas plant as a case study. Through Life Cycle Assessment (LCA) and Techno-Economic Analysis (TEA), the performance of co-digestion in reducing carbon emissions, controlling acidification, and mitigating particulate matter emissions was evaluated, alongside an analysis of its economic profitability. The results show that the NSR achieves a Net Present Value (NPV) of 23,800 kSEK, and an Internal Rate of Return (IRR) of 13.2%, indicating strong economic feasibility. In terms of environmental benefits, the co-digestion technology demonstrates a Global Warming Potential (GWP) of 23.26 kg CO₂ eq, a Particulate Matter Formation Potential (PMFP) of 0.015 kg PM2.5 eq, and a Water Consumption Potential (WCP) of 0.35 m³, highlighting its significant potential for water saving. However, the Acidification Potential (AP) of 0.16 kg SO₂ eq suggests the need for further optimization in acid pollution management. Sensitivity analysis reveals that fluctuations in electricity prices and government subsidies significantly impact the project’s economic performance. Overall, co-digestion technology performs exceptionally well in both economic and environmental aspects, serving as an effective pathway for sustainable, low-carbon emission development. Its long-term success will require continued policy support and further technological advancements.