Energy and Exergy Analysis and Optimization of a Pentageneration (Cooling, Heating, Power, Water and Hydrogen)

The proposed poly-generation plant, which generates power, cooling, and freshwater, consists of five subsystems. A solid oxide fuel cell (SOFC) plant generates electricity using CH4 as fuel. Steam Reforming happens in the anode to generate the required H2 for the electrochemical process. The thermal energy of these processes enhances the exhaust gas temperature from the solid oxide fuel cell plant, which can be reused using a Kalina cycle and humidification-dehumidification-RO desalination plants. This exhaust gas from the afterburner of a solid oxide fuel cell evaporates the ammonia-water mixture in a Kalina cycle and preheats the feedwater to be entered into the humidifier of the desalination unit. There has been an evaluation of the effect of various system parameters such as turbine inlet temperature, compressor pressure ratio, carbon dioxide to methane molar ratio, steam generator temperature, and mass flow ratio of the desalination system on overall system performance. Also, single- and multi-objective optimization methods have been used to optimize the general system compared to the base model.