Energy & Fuels, Vol.35, No.1, 670-689, 2021
Design and Optimization of a Dual Renewable Energy-Based Plant Utilizing Integrated Hydrogen to Ammonia and Fuel Cell Systems
In this study, a dual renewable energy-based plant is designed for producing clean hydrogen, ammonia, and electricity through integrated usage of wind and solar energy. An integrated molten salt-based electrochemical ammonia synthesis and fuel cell system is utilized. The overall system performance is investigated under different combinations of solar intensities and wind speeds. The studies are undertaken to perform an exergoeconomic analysis and a multi-objective optimization of the present system. The base-case scenario comprising average conditions is determined to have a total cost rate of $3690/h and an overall exergy efficiency of 29%. Moreover, the rates of cost of exergy destruction in each subsystem are investigated. The base-case overall exergoeconomic factor is found to be 56.9% denoting a major contribution of exergy destruction cost rates in total system costs. Furthermore, to determine the optimal system operational points, a genetic algorithm-based multi-objective optimization is performed. The highest exergy efficiency is evaluated to be 35.3% with a corresponding total rate of cost of $689/h, which is associated with a high value of solar intensity and low value of wind speed. The higher solar intensities are found to provide better, higher exergoeconomic performances that are attributed to the higher contributions of solar-based power generation subsystems that entail higher efficiencies as compared to other system components.