Co-benefits of the liquid hydrogen economy and LNG economy: Advances in LNG integrating LH2 production processes

Abstract

Against the global energy transition towards decarbonization and zero-carbon targets, hydrogen (H2) has emerged as a promising medium for energy storage and transportation in large-scale systems. Simultaneously, liquefied natural gas (LNG), serves as a transitional resource in moving towards cleaner energy sources. Consequently, the integration of LNG into liquid hydrogen (LH2) has garnered significant attention in recent years. This paper comprehensively reviews current research on LH2 production processes by integrating the energy mass of LNG. These processes, which include pre-cooling H2 utilizing the cold energy released from LNG regasification, producing blue H2 from natural gas (NG) derived from LNG regasification, synergistic liquefaction of NG and H2, and simultaneous production of LNG and LH2 from industrial by-products, can markedly increase the thermodynamic efficiency. Furthermore, this study explores potential future developments that could benefit both aspects of the LH2-LNG economy, thereby expanding the scope of related research. The integration of LNG into the LH2 production process through an energy mass approach, aimed at creating a mutually beneficial LH2-LNG economy, is an effective strategy for fostering energy transition. Finally, a brief discussion is presented on the constraints and challenges that may affect the future growth of the global LH2-LNG economy.