A mini-review of energy hub: concept, components, classifications, and applications

Addressing environmental degradation and mitigating climate change have become global priorities. In this context, energy plays a central role in enabling sustainable development pathways. Currently, fossil fuels comprise a large portion of the energy mix, and a solution is needed to shift towards sustainable futures. Traditional energy systems operated in isolation, resulting in significant inefficiencies across various sectors. However, the development of advanced multi-generation technologies and increasing integration of renewable energy have revealed the benefits of improved efficiency and reduced operational costs through coordinated multi-energy systems, driving a rapid transition toward implementing energy hub frameworks. Energy hubs are an emerging solution for optimizing multi-energy systems by integrating and managing various energy carriers, thereby enhancing efficiency, reducing costs, and minimizing environmental impacts. This mini-review systematically examines various aspects of energy hubs to provide an understanding of their role in sustainable energy transitions. After a brief introduction of fundamental concepts, the study investigates four principal components, including input sources, conversion and transmission technologies, energy storage systems, and demand outputs across six primary application sectors: residential, commercial, industrial, agricultural, transportation, and energy island. Also, this review further explores the application of artificial intelligence in energy hubs, moving beyond classical optimization to address the growing challenges of system complexity and uncertainty. The literatures demonstrate that energy hubs contribute to cost reduction and emission mitigation, while enhancing system flexibility and facilitating the integration of renewable energy. • Energy hubs are a promising approach for facilitating the transition toward sustainable energy systems. • Different aspects of the energy hub, including the concept, components, classifications, and applications, have been reviewed. • Review classifies energy hubs into six types: residential, commercial, industrial, transport, agriculture and energy islands. • Application of optimization methods and AI-based approaches for planning and operating energy hubs has been examined.