Liquid hydrogen refueling stations as an alternative to gaseous hydrogen refueling stations: Process development and integrative analyses

Abstract

The use of clean hydrogen is gaining attention as part of efforts to establish a sustainable energy value chain. However, current hydrogen refueling stations remain energy-intensive. To utilize hydrogen more cleanly, a thorough analysis of hydrogen refueling stations from an energy efficiency perspective is necessary. Liquid hydrogen refueling stations are emerging as an environmentally friendly alternative to current gaseous hydrogen refueling stations. For liquid hydrogen refueling stations to carve out a niche in a well-established market dominated by gaseous hydrogen refueling stations, the hydrogen selling price must be competitive. In this research, an energy-optimized design for liquid hydrogen refueling stations was proposed, focusing on reducing operating costs and mitigating potential environmental impacts. The developed design integrated three energy-saving systems into a basic liquid hydrogen refueling station: 1) a heat exchange system for hydrogen pre-cooling, 2) an organic Rankine cycle for waste heat recovery, and 3) a catalytic combustor for utilizing boil-off gas. To assess the viability of the integrated process, case studies were conducted focusing on economic, environmental, energy, and exergy performance. Consequently, the proposed design with integrated energy-saving systems demonstrated that while it increased the minimum hydrogen selling price by 5 % compared to the basic liquid hydrogen refueling station, it could reduce global warming potential by 41 %. We expect that our results will provide a better way to build the infrastructure of hydrogen refueling stations with the growth of the future hydrogen fuel cell electric vehicle market.