NTPC Transactions on Energy Research

Developing a static metal hydride-based hydrogen compression system with minimal thermal energy requirements and low maintenance is key to building a robust and efficient hydrogen microgrid, where compression plays a critical role. A hydrogen microgrid constitutes a viable approach for the sustainable supply and storage of energy across industrial, institutional, and remote community sectors. The green hydrogen microgrid encompasses renewable energy sources (RES) for electricity generation, in conjunction with integrated systems for hydrogen production, compression, storage, and fuel cell-based energy conversion. To address the challenge of hydrogen compression for high-pressure storage in hydrogen microgrids, a three-stage metal hydride hydrogen compressor (MHHC) was developed. This system overcomes the typical delivery pressure limitation (<100 bar) by compressing hydrogen to pressures exceeding 150 bar. The three-stage MHHC was successfully commissioned and tested, achieving a delivery pressure of 160 bar with heat transfer fluid (HTF) circulated at approximately 45℃. This approach demonstrates techno-commercial viability, particularly when the MHHC is operated utilizing waste heat or renewable thermal energy sources. Overall, the findings underscore thermochemical hydrogen compression as a robust and energy-efficient approach for hydrogen microgrid applications, effectively meeting the escalating energy demands in remote and hard-to-access regions.