Life Cycle Assessment of Greenhouse Gas Emissions in Hydrogen Production via High-Calorific Mixed Waste Gasification

This study evaluates the environmental sustainability of hydrogen production from high-calorific mixed waste gasification through a Gate-to-Gate (GtG) Life Cycle Assessment (LCA) based on operational data from a 2 TPD pilot plant. The Global Warming Potential (GWP) was calculated to be 9.80 kg CO2-eq per kg of H2 produced. A contribution analysis identified the primary environmental hotspots as external electricity consumption (37.0%), chelated iron production for syngas cleaning (19.5%), externally supplied oxygen 18.6%), and plant construction (12.3%). A comparative analysis, contextualized within South Korea’s energy structure, demonstrates this GWP is competitive with regionally contextualized Steam Methane Reforming (SMR) and lower than coal gasification. Furthermore, a scenario analysis based on national energy policies reveals a clear pathway for GWP reduction. Aligning with the 2030 renewable energy target (20% RE share) reduces the GWP to 9.14 kg CO2-eq, while a full transition to 100% wind power lowers it to 6.27 kg CO2-eq. These findings establish this Waste-to-Hydrogen (WtH) technology as a promising transitional solution that simultaneously valorizes problematic waste. This research provides a critical empirical benchmark for the technology’s commercialization and establishes an internationally transferable framework. It confirms that the technology’s ultimate environmental sustainability is intrinsically linked to the decarbonization of the local electricity grid.