Decarbonization potential in Southeast Asia through hydrogen production from waste biomass

Southeast Asia has substantial waste biomass resources that can support low-carbon hydrogen production and regional decarbonization. This study assesses biomass availability and compares the hydrogen production and decarbonization potential of two pathways: biomass gasification with steam methane reforming (BGSMR) and anaerobic digestion with biogas steam reforming (ADBSR). Crop residues, animal manure, and organic municipal solid waste are quantified across ten Southeast Asian countries, and associated hydrogen and CO 2 mitigation potentials are estimated. The results show that BGSMR consistently outperforms ADBSR across all countries, driven by its ability to directly utilize abundant lignocellulosic crop residues that dominate the regional biomass resource base. BGSMR provides a regional decarbonization potential of 4986 million t CO 2 , compared with 407 million t CO 2 for ADBSR, against current fossil-based emissions of 1681 million t CO 2 . Scenario analysis confirms robust mitigation outcomes even under conservative biomass availability. A market equilibrium assessment indicates that meeting current regional hydrogen demand (∼4 million tonnes yr −1 ) would require only about 5.6% of surplus biomass availability. Overall, BGSMR emerges as a scalable and resource-efficient pathway for hydrogen-based decarbonization in Southeast Asia.