Research on an integrated power and freshwater generation system from natural gas energy and geothermal sources

Waste heat recovery can recognize as a promising option for responding to the thermodynamic effectiveness and environmental issues through well-organized designs of multigeneration systems. Hence, this paper introduces a novel hybridization of a flash-binary geothermal cycle, a gas turbine cycle, an organic flash cycle, and a multi effect desalination subsystem to reach efficient cogeneration of electricity and freshwater regarding the smart use of waste heat. The capability of the proposed system is analyzed based on energy, exergy, exergoeconomic, and economic perspectives, where the net present value and payback were considered as the system's evaluation criteria from the economic viewpoint. Accordingly, the multi-objective grey wolf optimization algorithm in conjunction with the LINMAP decision-making approach has been utilized to optimize the system and specify the optimal conditions in three optimization scenarios. According to the base operation conditions, the system has an exergy efficiency of 37.45% with a power generation capacity of 19.02 MW, a total freshwater rate of 38.69 kg/s, and a total profit and payback period of 60.07 $M and 3.75 years. Besides, the triple-objective optimization illustrated the exergy efficiency, profitability, and payback period of 38.41%, 62.71 M$, and 3.26 years, respectively.