This book focuses on the science, technology, and safety aspects of hydrogen across the entire energy chain, from production and storage to combustion and applications. It provides a unified understanding of how hydrogen can serve as a sustainable fuel for clean transportation and power generation, addressing both its opportunities and engineering challenges. This book highlights key topics such as hydrogen properties, combustion fundamentals, safety mechanisms, and modeling of ignition and dispersion phenomena. It also discusses the integration of hydrogen engine and fuel-cell along with recent advances in computational and experimental methods for hydrogen combustion. This book is an essential resource for researchers, engineers, and graduate students in mechanical and energy engineering, as well as professionals working in the fields of hydrogen safety, combustion science, renewable energy systems, and sustainable mobility technologies.

Prof. Sage L. Kokjohn is a professor of Mechanical Engineering at the University of Wisconsin–Madison, where he leads research at the Engine Research Center (ERC). He earned his Ph.D. (2012) and M.S. (2008) in Mechanical Engineering from the University of Wisconsin–Madison and his B.S. (2006) from Iowa State University. Before joining UW–Madison, he worked as a senior research engineer at Cummins Inc. Prof. Kokjohn’s research focuses on advancing high-efficiency, low-emission energy conversion systems through detailed modeling and experiments. His work spans turbulent combustion modeling, alternative fuel utilization, pre-chamber ignition, hybrid powertrains, and hydrogen combustion. He has published more than 100 technical papers, holds multiple U.S. patents, and his work has been cited over 9,000 times. He currently serves as an editor of the International Journal of Engine Research and has organized several technical sessions for ASME and SAE conferences.

Prof. Avinash Kumar Agarwal is currently serving as Director at IIT Jodhpur. He obtained his Undergraduate Degree in Mechanical Engineering (1994) from Malaviya Regional Engineering College, Jaipur, and his M.Tech. (Energy, 1996) and Ph.D. (Energy, 1999) from the Indian Institute of Technology (IIT) Delhi. After his Post-Doctoral Fellowship (1999–2001) at the ERC, UW, Madison, USA, he returned to India in 2001 and joined IIT Kanpur. Prof. Agarwal has established a state-of-the-art “Engine Research Laboratory” at IIT Kanpur. Prof. Agarwal is interested in researching IC engines, combustion, conventional and alternative fuels, optical diagnostics, laser ignition, HCCI, particulates and emission control, and large bore engines. Prof. Agarwal has published over 550+ peer-reviewed international journal and conference papers, 65 edited books, and 129 book chapters, attracting 18,300+ Scopus and 27,400+ Google Scholar citations. He is an elected fellow of TWAS, SAE, ASME, INAE, ISEES, RSC, NASI, WSSET, AAAS, and Combustion Institute USA.

Dr. Dhananjay Kumar is a postdoctoral Researcher at the Engine Research Center (ERC), University of Wisconsin–Madison, USA. He received his Ph.D. in Mechanical Engineering from the Indian Institute of Technology (IIT) Kanpur and his B.Tech. in Mechanical Engineering from the National Institute of Technology (NIT) Mizoram, India. His research focuses on hydrogen safety, combustion of alternative fuels, and ignition phenomena during battery thermal runaway (BTR). His work combines simulation and experimental diagnostics to study particle-induced ignition, fuel–air mixing, and heat transfer processes relevant to decarbonized energy systems. Dr. Kumar has published several journal articles, book chapters, and conference papers in the fields of hydrogen and alternative fuel combustion, and his current research contributes to understanding hydrogen as a clean energy carrier and developing safe, efficient, and low-emission energy conversion technologies.