Multi-criteria evaluation of agricultural and woody biomass pellets under standardized conditions for fuel quality and emission performance

The efficient utilization of agricultural and woody biomass residues as renewable energy resources requires reliable and standardized evaluation of pellet fuel performance. In this study, a multi-criteria assessment of biomass pellets produced from five feedstocks—peach pruning, vine pruning, sunflower stalk, canola stalk, and hazelnut husk—was carried out under identical pelletization conditions. Fuel, mechanical, density, and emission properties were experimentally evaluated using standardized methods. Peach pruning pellets exhibited the highest higher heating value (4,521 cal g−1), while vine pruning pellets achieved the highest mechanical durability (97.0%). In contrast, sunflower and canola stalk pellets exhibited substantially higher ash contents (14.4% and 14.6%, respectively). Emission measurements further showed that woody biomass pellets produced lower CO emissions and more stable combustion behavior than herbaceous biomass pellets. These findings indicate that woody biomass residues generally provide superior fuel quality and combustion performance under identical pelletization conditions. The proposed standardized multi-criteria evaluation framework provides practical guidance for biomass feedstock selection and optimization in sustainable pellet production.