Design and thermoeconomic optimization of a solid oxide fuel cell-driven multigeneration structure for integrated power, cooling, and freshwater production

The efficient utilization of fossil fuels to reach a higher performance and discounting their environmental impact is an important challenge. The solid oxide fuel cell technology offers a higher efficiency and lower environmental impact compared to the traditional use of them for power production. Hence, this paper introduces an innovative solid oxide fuel cell-based multi-generation system to produce power, cooling, and freshwater. The system consists of a dual-pressure organic Rankine cycle, ejector refrigeration cycle, and humidification-dehumidification cascade for waste heat recovery assessment. The key novelty in this study lies in recycling the cathode and anode flue gases for elevated waste heat recovery and cost-effectiveness. The designed multi-generation system undergoes a comprehensive thermodynamic and economic analysis to estimate the performance indexes, which are involved in a sensitivity examination and multi-objective optimization procedure. Under optimum conditions, the system gives out a net power output of 1294 kW, a cooling load of 487.6 kW, and a freshwater production rate of 0.246 kg/s. The exergy efficiency reaches 30.1 %, with an energetic efficiency of 41.87 %. Economically, the presented structure requires a fixed capital investment of 2.614 $M, delivers a net present value of 3.42 $M, and achieves a payback period of 3.69 years. These outputs highlight the economic and technical viability of the proposed configuration as a sustainable solution for integrated energy structures.