Comprehensive thermodynamic, economic, and environmental analysis of a novel cooling and water cogeneration system based on seawater evaporation

In this study, an innovative system is presented to co-generate water and cooling energy on the base of seawater evaporation. Salt-free vapor can be separated from the seawater through the evaporation process, meanwhile, seawater evaporated under low pressure can provide cooling energy. The compressor is employed to create a low-pressure environment for seawater, and the compression heat is recovered by a multi-effect desalination subsystem to produce freshwater. A comprehensive comparison is conducted between this system and conventional systems, considering thermodynamic, economic, and environmental aspects. Meanwhile, the exergoeconomic analysis was conducted for the proposed system. The calculation results indicate that the specific energy consumption of the proposed system is 19.77 kWh/t, which is 4.53 kWh/t lower than that of the conventional system (23.76 kWh/t). Additionally, higher gain output ratio and performance ratio can be achieved. The proposed system has a payback period of 4.24 years, which is shorter than the 6.21 years required by the conventional system, thereby demonstrating a greater economic advantage. For the environmental performance, the proposed system demonstrates a reduced CO2 emission of only 12.55 kg/$, indicating a significant decrease of 40.29% compared to the conventional system's 21.02 kg/$. Therefore, the proposed system demonstrates improved economic and environmental performance.