An Environmental and Economic Assessment of Household Food Waste Management Scenarios in Ireland

Effective management of household food waste (HFW) is essential for sustainability and aligning with Ireland’s waste reduction goals. This study evaluates the environmental and economic impacts of four HFW management scenarios—incineration, anaerobic digestion (AD) with digestate composting, AD with digestate incineration, and AD with digestate gasification—using life cycle assessment (LCA) and life cycle costing (LCC) analyses. The functional unit is 1000 tons of daily HFW treatment. The results show that AD scenarios offer significant environmental advantages over incineration, with AD combined with digestate composting identified as the most sustainable option. This scenario achieves the greatest reduction in greenhouse gas emissions and enhances nutrient recovery. Economically, while AD involves higher capital investments (€677,000–€2,033,000), its long-term cost effectiveness is demonstrated through LCCs ranging from €1,016,000 to €3,386,000, partially offset by revenues of €339,000–€677,000. The sensitivity analysis highlights opportunities for improvement, such as optimizing water use and reducing emissions from biogas engines. The findings provide actionable insights for policymakers, emphasizing the environmental and economic benefits of integrating AD with composting as a preferred strategy for HFW management.