Comparative Life Cycle Assessment of Hydrogen Production via Biogas Reforming and Agricultural Residue Gasification

Hydrogen (H2) production from biomass has emerged as a promising alternative to fossil-based pathways, addressing the global demand for low-carbon energy solutions. This study compares the environmental impacts of two biomass-based H2 production processes, biogas reforming and agricultural residue gasification, through a life cycle assessment (LCA). Using real-world data from the literature, the analysis considered key system boundaries for each process, including biogas production, reforming, and infrastructure, for the former, and biomass cultivation, syngas generation, and offgas management, for the latter. Environmental impacts were evaluated using SimaPro software (Version 9.4) and the ReCiPe midpoint (H) method. The results revealed that biogas reforming emits approximately 5.047 kg CO2-eq per kg of H2, which is 4.89 times higher than the emissions from agricultural residue gasification (1.30 kg CO2-eq/kg H2), demonstrating the latter’s superior environmental performance. Gasification consumes fewer fossil resources (3.20 vs. 10.42 kg oil-eq) and poses significantly lower risks to human health (1.51 vs. 23.28 kg 1,4-DCB-eq). Gasification water consumption is markedly higher (5.37 compared to biogas reforming (0.041 m3/kg H2)), which is an important factor to consider for sustainability. These findings highlight gasification as a more sustainable H2 production method and emphasize its potential as an eco-friendly solution. To advance sustainability in energy systems, integrating socio-economic studies with LCA is recommended, alongside prioritizing agricultural residue gasification for hydrogen production.