High-pressure, grid-independent hydrogen generation via chemical hydride hydrolysis: Demonstration and deployment strategies

Abstract

High-pressure hydrogen refueling stations currently face challenges due to their reliance on mechanical compressors with high electricity consumption, grid dependency, durability issues and stringent installation requirements. This study introduces a non-mechanical, grid-independent hydrogen on-site production and compression system utilizing acid-mediated hydrolysis of sodium borohydride (SBH). The system harnesses the highly exergonic reaction of formic acid-assisted SBH hydrolysis, potentially reaching pressures up to 90.0 MPa, suitable for dispensing 75.0 MPa compressed hydrogen with negligible external energy consumption (0.63 kWh center dot kgH2-1). Through statistical analysis called ANOVA (analysis of variance), we identify critical parameters affecting SBH conversion, hydrogen storage density, and impurity levels needed for optimal system operation and its successful deployment. The optimized system operated above 48.8 MPa, while achieving an output density of 3,300 Nm3 H2 center dot h-1 center dot m-3 system, and hydrogen purity requirements for polymer electrolyte membrane fuel cells (PEMFCs). A techno-economic assessment (TEA) demonstrates the system's potential economic viability as SBH prices decrease, making it suitable for mobile and emergency applications with high necessity and low utilization rate. This innovative SBH-based method addresses the limitations of conventional mechanical compressors, offering a compact, efficient, and autonomous solution for high-pressure hydrogen production. The approach presents a promising alternative for advancing hydrogen refueling infrastructure, potentially revolutionizing the field of sustainable energy storage and distribution.