Household Food Waste to Biogas in Västerås, Sweden: A Comprehensive Case Study of Waste Valorization
Sustainable large-scale household food waste (HFW) reutilization is difficult worldwide. This study presents a systematic and in-depth analysis of the case of Västerås, Sweden, where biogas has been produced from HFW for years and utilized as renewable vehicle fuel. Various aspects are covered, including the logistic flow, energy recovery, environmental benefits, cost-benefit analysis, and social survey. In 2017, 8879 tons of food waste were collected from Västerås city, which could generate 590,000 Nm3 biomethane and support 21 biogas-powered buses. A reduction of 1052.9–1541.2 tons of CO2-eq was estimated by replacing fossil fuels in vehicles and centralized composting units for HFW. The actual operating profit of this process amounted to 6.604 million Swedish Krona (SEK), and the maximized environmental economic benefit was estimated to be 3.15–3.73 million SEK/year. The active participation of the residents to source-separate their HFW was crucial to the success of the project, and the driving factors were tentatively identified as value orientation and facility convenience. With information pooled from various sectors, this study constructs a comprehensive reference case for industrial, academic, and municipal entities that are interested in similar practices in the future.