Energy and Exergy Analysis of a Metal Hydride-Based Hydrogen Storage System: A Parametric Approach

Abstract

Hydrogen is considered a promising energy carrier for the global energy transition due to its high energy density and environmental sustainability. However, the efficient storage of hydrogen remains a major technical challenge that limits its large-scale deployment. Metal hydrides (MHs) offer a safe and compact solution, but their thermal management strongly influences storage efficiency.This study conducts a comprehensive energy and exergy analysis of a magnesium hydride (MgH₂)-based storage system to evaluate the combined influence of key parameters: reactor number, outlet temperature, coolant mass flow rate, pump efficiency, ambient temperature, heat transfer coefficient, hydrogen capacity, and the volume-to-surface (V/A) ratio. The numerical model integrates energy–exergy formulations to quantify performance under different operating conditions.The results reveal that increasing the number of reactors enhances exergy efficiency from 21.5% to 64.9%, while higher outlet temperatures and mass flow rates reduce efficiency due to thermal imbalance and pumping losses. In contrast, improving the heat transfer coefficient up to 3000 W/m²·K increases efficiency to 73.9%, demonstrating the critical role of thermal design.These findings provide design guidelines for optimizing reactor configuration, flow management, and material selection. The study offers practical insights for engineering applications and supports the development of scalable, high-efficiency MH-based hydrogen storage systems.

Keywords

• Hydrogen storage
• Metal hydride reactor
• Energy analysis
• Exergy efficiency
• Thermal management
• MATLAB modeling

Kaynakça

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