Transient analysis and evaluation of a novel pressurized multistage ammonia production system for hydrogen storage purposes

A novel and practical hydrogen storage system is developed and analyzed thermodynamically through transient energy and exergy approaches. The proposed hydrogen storage system stores the hydrogen chemically in the form of ammonia, and it is a pressurized in the multistage ammonia production system. The pressurized multistage ammonia production system stores the produced ammonia in a novel conceptual design of an ammonia tanker truck equipped with an ammonia electrolyzer, which transports and delivers the stored hydrogen. The energy and exergy efficiencies of the proposed system are found to be 72.3% and 71.8%, respectively. The proposed system consumes an amount of 59.5 kJ of work per mole of hydrogen stored and recovered using the ammonia electrolyzer. The system is simulated on filling 21,000 L of ammonia at a pressure of 61 bar, and the system is able to store 13,225 kg of ammonia in a liquid state in 0.518 h. The system consumes nearly 61.4 GJ of energy to store the 13,225 kg of ammonia and to decompose it during the discharge phase.