The potential of agricultural residues for energy production in Calabria (Southern Italy)

This work aims at estimating the biomass from agricultural residues of Calabria region (Southern Italy) for possible energy conversion in combined heat and power (CHP) systems. To this purpose, attention has been focused on agricultural residues, livestock sewage, and by-products and waste of the agro-food industry. The investigation has been based on statistical information from 2015, and an extensive literature review has been performed to define proper parameters for the analysis. The study highlights that an interesting amount of biomass residues is present in the investigated area, with about 820,000 t per year that can be conveniently used in small-scale CHP units to satisfy the thermal and electric request of regional users. Specifically, Organic Rankine Cycle (ORC) systems have been considered to exploit lignocellulosic residues through direct combustion, while anaerobic digestion and internal combustion engines (ICEs) have been adopted for the energy valorisation of the other investigated feedstock. The analysis demonstrates that the available biomass residues could satisfy the thermal request of more than 116,000 households and the electric load of about 178,000 families simultaneously.