A life cycle analysis of liquid and gaseous hydrogen transportation pathways

Hydrogen is key to transportation decarbonization in California, but environmental impacts of hydrogen delivery remain uncertain. We compare life cycle impacts of transporting hydrogen in gaseous and liquid form by truck using a gate-to-pump attributional boundary and a functional unit of 1 MJ of hydrogen delivered to a refueling station. Nine environmental impact categories are evaluated including climate change and human toxicity. Results show that liquid hydrogen pathway produces 35% higher CO 2eq emissions and 40% higher acidification potential than gaseous pathway. Despite economic advantages, liquid hydrogen transport is more energy-intensive with liquefaction and boil-off losses. Gaseous hydrogen exhibits lower impacts, with compression and storage at refueling stations being dominant contributors, while liquefaction is the primary driver for the liquid pathway. These findings highlight the importance of hydrogen delivery mode and provide insights to support infrastructure planning and efficiency improvements in California. • Compares truck-based gaseous and liquid hydrogen delivery in California using a gate-to-pump life cycle assessment. • Liquid hydrogen transport shows ∼35% higher CO 2eq emissions and ∼40% higher acidification than gaseous delivery. • Compression and storage dominate impacts for gaseous hydrogen, while liquefaction drives impacts for liquid hydrogen. • Over an 800-mile intrastate route, gaseous hydrogen uses less energy and water in nearly all categories. • Results support LCFS pathway evaluation by showing lower impacts for gaseous hydrogen delivery in California.