Evaluating the environmental impact of electricity generation from combined heat and power plants utilizing woody biomass: A life cycle assessment approach

Despite growing interest in renewable energy, there is still a lack of comprehensive, site-specific life cycle assessment (LCA) studies comparing alternative woody biomass-to-electricity pathways. To address this gap, this study evaluates the environmental performance of three distinct woody biomass-based energy generation scenarios, from cradle to grave, using the LCA methodology. The scenarios include the use of wood chips derived from forest residues and biopellets produced from sawmill residues, each representing different processing and utilization approaches. In Case A, sawmill residues collected from three nearby cities are dried using heat recovered from the CHP system to produce biopellets. In Case B, sawmill residues from a single city are dried using natural gas before pelletization. Case C involves the direct use of wood chips derived from forest residues, which are collected, chipped, and utilized in a CHP plant without further preprocessing. The environmental impact of each pathway is assessed based on Global Warming Potential (GWP). The calculated GWP values are −15 gCO_2eq/kWh_e (Case A), 74.4 gCO_2eq/kWh_e (Case B), and −78.63 gCO_2eq/kWh_e (Case C), indicating substantial reductions in greenhouse gas emissions compared to fossil-based electricity generation. The results reveal that all scenarios are environmentally favorable, with the most significant benefits observed in Case C. The inclusion of heat credits significantly improves the performance of Cases A and C. These findings emphasize the potential of woody biomass and CHP systems in supporting low-carbon energy transitions, particularly in Türkiye and other regions with abundant forest and sawmill residues. The study provides site-specific insights that can inform future policy and investment decisions in sustainable bioenergy systems.