Lifecycle emissions of hydrogen supply chains in China: A spatially resolved assessment

Abstract

Current hydrogen delivery assessments exhibit incomplete supply chain coverage, insufficient carrier diversity, and oversimplified spatial analysis relying on hypothetical distances. This study addresses these limitations through comprehensive life cycle assessment across China's four major transport routes for 2030–2060, evaluating 12 delivery systems comprising four transportation modes (pipeline, truck, ship, ultra-high-voltage transmission) and six hydrogen carriers across 25 sub-routes with actual geographic constraints and provincial energy profiles. Results reveal that spatial heterogeneity in regional energy systems rather than transport distance constitutes the primary determinant of delivery emissions. For the same delivery mode, emissions varied markedly across provinces because of differences in electricity carbon intensity, from 0.64 kg CO2eq/kg H₂eq for Pipeline-CGH2 on Yunnan–Guizhou to 1.98 kg CO2eq/kg H2eq on Inner Mongolia–Shanxi in 2030. Non-optimal mode selection further caused large emission penalties, especially in high-carbon routes and in later years. UHV-electricity transmission achieves the lowest emissions across 88% of sub-routes (0.03–0.31 kg CO₂eq/kg H₂eq by 2060), while ship-based transport demonstrates competitive performance in only one of three waterway-accessible routes, with this advantage reversing by 2060 due to accelerating grid decarbonization. Lifecycle stage decomposition indicates delivery-stage emissions dominate truck-based systems (>60%), while post-delivery processing dominates carrier-based modes. These findings demonstrate that hydrogen infrastructure planning requires regionally-differentiated strategies: priority UHV deployment for northwestern-to-eastern routes where emission disparities between optimal and suboptimal modes are most substantial, flexible multi-modal approaches for southwestern routes, and selective waterway infrastructure investment. This spatially-explicit framework provides evidence-based guidance demonstrating that regional energy profiles fundamentally shape delivery system performance beyond conventional distance-based optimization.