Dynamic analysis of metal hydrides and liquid hydrogen supply system for a fuel cell ship

Abstract

Recently, hydrogen has been attracting attention in the field of shipping from the viewpoint of global warming prevention and environmental protection. Liquified hydrogen, which is one of the hydrogen storage methods, has high transportation efficiency and is suitable for use in ships. On the other hand, boil-off gas (BOG) from liquified hydrogen is generated and leads to unstable for system operation due to the large temperature difference with the outside air, and it is an issue that needs to be addressed. To come up with an effective method for dealing with the problem, the use of metal hydrides (MH) for fuel cell system, which can reversibly adsorb and desorb hydrogen, can be a solution to this problem when the ship is stationary or cruising. However, the system operation of fuel cell ship driven by liquified hydrogen as power source has not been reported so far. Therefore, this study aims at clarifying the dynamic characteristics of the liquid hydrogen supply system using MH. In this paper, we conduct numerical simulations using mathematical models of the system components to evaluate the system response on load variation of fuel cell. As a result, it is revealed that the fuel supply system can be operated stably against the load variation by suggested control system.