The evolution of green hydrogen in renewable energy research: Insights from a bibliometric perspective

Green hydrogen, generated from water through renewable energies like solar and wind, is a key player in sustainable energy. It only produces water when used, making it a clean energy source. However, the inconsistent nature of solar and wind energy highlights the need for storage solutions, where green hydrogen is promising. This study uniquely combines green hydrogen (GH) and renewable energy (RE) domains using a comprehensive bibliometric approach covering 2018–2022. It identifies emerging trends, collaboration networks, and key contributors that shape the global landscape of GH research. Our findings show a significant yearly growth in this research field, averaging 93.56 %. The study also identifies China, Germany, India, and Italy as leaders among 76 countries involved in this area. Research trends have shifted from technical details to social and economic factors. Given the increasing global commitment to achieving carbon neutrality, understanding the evolution and integration of GH within RE systems is essential for guiding future research, policy-making, and technology development. The analysis categorizes the research into seven main themes, focusing on green hydrogen's role in energy transition and storage. Other vital topics include improving hydrogen production methods, assessing its climate impact, examining its environmental benefits, and exploring various production techniques like water electrolysis and photocatalysis. Our analysis reveals a 93.56 % annual growth rate in GH research, highlighting key challenges in storage, integration, and policy development, and offering a roadmap for future studies. The study highlights areas needing more exploration, such as better storage methods, integration with existing energy infrastructures, risk management, and policy development. The advancement of green hydrogen as a sustainable energy solution depends on innovative research, international collaboration, and supportive policy frameworks.