Designing the biomethane production chain from urban wastes at the regional level: An application to the Rome Metropolitan Area

This paper proposes a methodology to design the biomethane production chain from MSW at the regional level and to assess the environmental and economic performance of the chain. In the design phase, the following parameters are considered: number and production capacity of biomethane plants, localization of plants, waste flows among municipalities and plants. The model is adopted to design the biomethane chain in the Rome Metropolitan Area (Italy). Several structures of production chain are designed and their performances are assessed. The economic factors mostly able to affect the performance of the chain are waste disposal tariff, biomethane selling price, and the economic incentive provided to biomethane producers. Their impacts are discussed through sensitivity analyses. Results show that the structure maximizing the economic performance has the worst environmental performance and vice versa. Hence, a new structure of the economic incentive is proposed, aimed at re-aligning economic and environmental performance.