Experimental investigation of an integrated solar powered clean hydrogen to ammonia synthesis system

In the present study, a solar-based clean ammonia synthesis system is newly developed and investigated experimentally. The required hydrogen for synthesizing ammonia is obtained through the proton exchange membrane based water splitting process powered by solar photovoltaic cells. The ammonia synthesis rate from the developed system is observed to be 0.016 mmol/s under the operating conditions considered. In addition, the developed system is investigated through thermodynamic energy and exergy approaches and the overall energy efficiency is found to entail a value of 1.9%. Also, the overall exergy efficiency is found to be 1.8%. Furthermore, the energy efficiency of the solar to hydrogen process is observed to be 2.4% and the corresponding exergy efficiency is evaluated as 2.1%. Moreover, the proton exchange membrane-based water electrolysis subsystem is found to have efficiencies of 19% and 15.3% both energetically and exergetically respectively. In addition, parametric studies are also performed to study the effects of changing operating conditions on the performance of the overall system as well as subsystems.