A review of green hydrogen energy storage as a sustainable and resilient storage solution for microgrids

• A comprehensive review on the evolution and key enabling technologies of GHES, examining components like electrolyzers and fuel cells, as well as operational frameworks and topologies. • A critical review to address the challenges posed by renewable energy intermittency and system nonlinearity. • An in-depth review highlighting the unique advantages of GHES, including enhanced power quality and decarbonization. • A holistic review in summarizing existing research and identifying a clear roadmap for future investigation, this paper confirms the transformative potential of GHES for modern MG networks. The rapid expansion of the global microgrid (MG) market requires a sustainable and resilient energy storage solution to manage the intermittent nature of renewable energy sources. While conventional battery storage systems are common, they present significant limitations in cost, lifespan, and environmental impact. This paper introduces green hydrogen energy storage (GHES) as a paradigm-shifting alternative for MGs, driven by the need for sustainability and resilience. This comprehensive review surveys the evolution and key enabling technologies of GHES, comparing its potential among different storage technologies, examining components such as electrolysers and fuel cells, and analysing storage technologies and their comparative analysis from an MG perspective, operational frameworks, and MG topologies, and different energy and power management controls and algorithms applied to GHES-based MGs. The paper critically surveys the challenges posed by renewable energy intermittency and system nonlinearity in GHES controllers and energy management, including power quality and decarbonization. This paper concludes a comprehensive future research direction with the transformative potential of GHES for modern MG networks by summarizing existing research and identifying a clear roadmap for future investigation.