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.

Objectives:This study aims to assess the environmental impact of the composting process, which constitutes 75.3% of the domestic livestock manure recycling methods, and to determine the environmental impacts of methane and nitrous oxide, the major greenhouse gases in the livestock sector, as well as ammonia, a precursor to fine particulate matter that has recently become a social issue. The analysis will focus on the categories of climate change and fine particulate matter formation to identify the most significant factors impacting the environment.Methods:This study applied the Life Cycle Assessment (LCA) methodology according to ISO 14040/14044 standards to evaluate the environmental impact of producing one bag (20kg) of livestock manure compost. The system boundary included the transportation of livestock manure and sawdust to the composting facility and the compost production process. The methodology applied for impact assessment was the ReCiPe 2016 v.1.1 Midpoint (H) method, which allows for a more global evaluation by utilizing worldwide average data.Results and Discussion:The impact assessment of livestock manure compost production revealed that producing one bag contributes 2.667 kg CO2-eq. to climate change, with electricity consumption responsible for 68.95% of emissions. Carbon dioxide (CO2) is the dominant greenhouse gas, making up 84.37% of the total. Particulate matter formation is 0.037 kg PM2.5-eq., with 91.97% resulting from emissions during the composting process. Ammonia (NH3) is the main cause of particulate matter, accounting for 92.02% of emissions.Conclusion:Based on the research, electricity consumption is the main factor affecting climate change in compost production, and ammonia is the primary cause of fine particulate matter. This study provides a case for evaluating the environmental impact of livestock manure composting and can serve as a foundational reference for developing policies and technologies to address climate change and fine particulate matter issues.

This study evaluates the environmental sustainability of hydrogen production from high-calorific mixed waste gasification through a Cradle-to-Gate(CtG) 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. This carbon footprint is competitive with conventional steam methane reforming (SMR) and lower than coal gasification, but significantly higher than biomass-based pathways. A contribution analysis identified the primary environmental hotspots as external electricity consumption (39.3%), production of chelated iron for syngas cleaning (18.8%), externally supplied oxygen (17.9%), and plant construction (11.9%). These findings position this Waste-to-Hydrogen (WtH) technology as a strategic transitional solution, offering the dual benefit of valorizing problematic waste and producing a valuable energy carrier. While not yet a 'green' hydrogen source, the identification of clear environmental hotspots provides actionable pathways for improving its sustainability, primarily through enhancing energy self-sufficiency and optimizing consumable usage. This research provides a critical empirical benchmark for the technology's future development and commercialization, bridging the gap between laboratory research and industrial application.

This study proposes a method for estimating life cycle greenhouse gas (GHG) emissions of a hydrogen fuel cell house using the Life Cycle Assessment (LCA) framework. Subsequently, a case analysis based on the proposed method was conducted to assess the GHG reduction potential of a hydrogen fuel cell house. To establish the life cycle GHG estimation method, international and domestic LCA-related standards, guidelines, and prior studies were reviewed. The method was evaluated in three sequential components: system boundary definition, data collection, and GHG calculation. The system boundary was established following the modular approach outlined in EN 15804. Data collection was based on case studies from domestic and international research as well as BOM (Bill of Materials) from hydrogen fuel cell house demonstration sites. The GHG calculation involved the formulation of estimation equations for individual items and the identification of applicable databases. Using the proposed method, the life cycle GHG emissions of a hydrogen fuel cell house utilizing reformer-based hydrogen were calculated to be 1.33E+03 kgCO₂-eq/m². A comparative analysis revealed that a hydrogen fuel cell house using clean hydrogen achieved a 20.3% reduction in life cycle GHG emissions compared to the reformer-based hydrogen house and a 19.2% reduction compared to conventional houses. The results indicate that hydrogen fuel cell houses offer emission reduction benefits, but their environmental impact is significantly influenced by the hydrogen production method. Additionally, the study highlights the importance of the transition of conventional houses to hydrogen fuel cell houses and the supply of low-carbon hydrogen for maximizing GHG reduction potential. These findings provide valuable insights for sustainable development of hydrogen-based residential energy systems and contribute to policy discussions on carbon-neutral urban infrastructure