Comprehensive assessment and sustainability improvement of a natural gas power plant utilizing an environmentally friendly combined cooling heating and power-desalination arrangement

Abstract

Considering the significant waste heat generated by existing natural gas power plants, it is imperative to implement eco-friendly combined process designs to ensure their long-term sustainability. The present paper introduces and investigates a novel integrated process aimed at achieving multiple generational advantages within an environmentally friendly framework, with the ultimate goal of enhancing sustainability. The new structure incorporates a natural gas power plant, high-temperature and low-temperature organic Rankine cycles, a combined cooling and power subsystem, and a water desalination unit to produce power, heating, cooling, and freshwater simultaneously. This system is simulated within the Aspen HYSYS software and examined from energy, exergy, economic, environmental, and sustainability perspectives. Furthermore, parametric studies evaluate the impact of the overall system's various environmental, economic, and operational conditions. It is found that the production capacities of power, hot water, chilled water, and freshwater are 179,265.17 kW, 387.8 kg/s, 563.6 kg/s, and 21.4 kg/s, respectively. Hence, the overall energy and exergy efficiencies improve to 66.06% and 42.95%, respectively. The financial estimation also reveals a cost of energy of 0.1084 $/kWh and a total net present value of 818.67 M$. It is also determined that the cost per unit of destroyed exergy is equal to 7.156 $/GJ.