Hydrogen as Maritime Transportation Fuel: A Pathway for Decarbonization

Shipping is the most energy-efficient way for the transportation of goods and it has a substantial role in the global economy. The vast majority of the ships are addicted to fossil fuels as an energy source due to economic advantages, strong bunkering nets, and well-experienced operations of marine diesel engines. However, environmental concerns drive the industry to take precautions on the ship-sourced greenhouse gas emissions, and the International Maritime Organization (IMO), the ruler of the maritime industry, is bringing strict rules to regulate the emissions under The International Convention for the Prevention of Pollution from Ships—Annex VI (MARPOL). On the way of decarbonization and emission-free shipping, marine alternative fuels may draw a framework for the future of the maritime industry. In this perspective, hydrogen is a promising alternative for maritime transportation with its carbon-free structure. Furthermore, green hydrogen is one of the electrofuels for maritime transportation to solve the issue to achieve full decarbonization. The use of hydrogen for ships is still under investigation at the level of research projects. Therefore, elaboration of the feasibility from different points of view for the commercial fleet is necessary to enlighten the future of the industry. This chapter includes information about the status of maritime transportation, recent international maritime emission rules and regulations, and hydrogen compliance with the International Code of Safety for Ships Using Gas or Other Low-flashpoint Fuels (IGF Code). Furthermore, hydrogen production technologies, onboard hydrogen storage methods, hydrogen combustion concepts on marine diesel engines, and fuel cells are reviewed. Lastly, the conclusion section comprises the chapter discussion.