Sustainability metrics for renewable energy production: Analysis of biomass-based energy plants in Italy

Biomass is an important energy feedstock and an alternative to fossil fuel. The development of biomass-based supply chains and energy conversion plants has to be calibrated to reflect local sustainability criteria. The aim of this study is to assess the environmental, economic, and social sustainability of a biomass-based district heating plant (DHP) and a combined heat and power plant (CHP) in Italy. The sustainability assessment was developed using three criteria: proximity between biomass and the energy producer and consumer; value added, employment, and impact of biomass supply chains; and environmental impacts. For each criterion, a set of sustainability metrics was developed and tested in two case studies in Northern Italy (Sarentino DHP and Cavalese CHP). The results suggested that the DHP and CHP (1) were supplied with local biomass residues located at distances of 11 km and 20 km, respectively; (2) provided energy to 55% and 83% of the total local population, respectively; (3) generated a value added of approximately (sic)2 million and (sic)1 million, created 4 and 8 local green jobs, and dedicated 52% and 64% of their external costs to the local biomass supply chain (wood production, transformation, and transport), respectively; and (4) contributed to the impact category of global warming potential with 7.6 gCO(2)eq./MJ (compared to 70-90 gCO(2)eq./MJ from fossil-fueled DHP) and 62 gCO(2)eq./MJ(cu) (compared to 100-300 gCO(2)eq./MJ(cu) from fossil-fueled CHP), respectively. Published by AIP Publishing.