Hydrogen from pine wood waste via pyrolysis and autothermal steam reforming: technoeconomic and environmental performance of single and co-production pathways

Biomass-based hydrogen production represents a promising pathway to reduce the environmental impacts associated with fossil-based hydrogen. In thermochemical pathways, biomass is typically converted into intermediate streams such as bio-oil prior to hydrogen production. However, in bio-oil reforming processes, a key unresolved question is whether hydrogen production should prioritize complete conversion of the pyrolysis liquid or selective upgrading of its aqueous fraction, recovering the organic fraction as a fuel co-product. In this work, the implications of both alternatives at industrial scale are systematically evaluated through an integrated techno-economic and environmental assessment, comparing two process configurations for hydrogen production from pine wood waste via fast pyrolysis coupled with autothermal reforming, and benchmarking them against conventional steam methane reforming. The results show that both biomass-based scenarios can reduce climate change impacts by approximately 80% compared to steam methane reforming. However, this benefit is accompanied by higher impacts in categories such as acidification and resource use (minerals and metals) due to electricity consumption and forest management. From an economic perspective, the configuration based on complete conversion of bio-oil leads to a levelized cost of hydrogen of 5.2 € 2025 /kg H 2 , which decreases to 2.8 € 2025 /kg H 2 when the organic fraction is co-produced as fuel for industrial heat boilers. Overall, the results demonstrate that the choice of bio-oil valorization strategy for hydrogen production constitutes a critical design variable, introducing a trade-off between hydrogen yield, economic performance and environmental impacts. The co-production strategy enhances economic robustness, while environmental differences between the two scenarios remain minor, and depend on the allocation approach and the impact category considered.