Integrated assessment of life-cycle energy performance from individual feedstocks suggested straw and corn silage as the most energy efficient for biogas production (Pöschl et al., 2010). This was mainly ascribed to the higher energy density, which exceeded the primary energy inputs for feedstock supply logistics (Pöschl et al.,2010). Also, the MSW, food residues and slaughterhouse waste feedstocks required pre-treatment/sterilization and collection/ transportation regime prior to utilization as feedstocks in AD process, hence, achieved less attractive energy balances (Pöschl et al., 2010).