Experimental investigation of a sustainable integrated ammonia synthesis and fuel cell system

•New integrated ammonia synthesis and fuel cell system experimentally investigated.•Charging and discharging exergy efficiencies found to be 17% and 49.2% respectively.•Hydrogen production entails highest exergy destruction ratio of 153.6 kJ/molH2.•Overall efficiency of the developed system found to be 8.4%. In the present study, an experimental investigation of a new integrated ammonia synthesis and fuel cell system is performed. A lab-scale clean ammonia synthesis system utilizing hydrogen produced through the water electrolysis route is integrated with a direct ammonia fuel cell system. The performance of the developed system is investigated under the two key phases of energy charging and discharging. The energetic and exergetic performances of associated subsystems are also investigated. An energy efficiency of 15.9% is found for the charging phase of the system and the system exergy efficiency for this phase is evaluated as 17%. Furthermore, the energetic and exergetic efficiencies for the discharging phase are determined as 52.3% and 49.2% respectively. The overall efficiency of the developed experimental system is evaluated as 8.4%. The exergy destruction ratios of associated subsystems are also evaluated and the proton exchange membrane-based water electrolysis subsystem entails the highest ratio of 153.6 kJ/molH2. In addition, the exergy destruction ratio of the ammonia synthesis subsystem is found to be 5.63 kJ/molNH3. Several parametric studies are also performed to investigate the system performances under varying operating parameters.