Exergo-economic analysis of a low-temperature geothermal-fed combined cooling and power system

In this work, a novel cogeneration system is analyzed. The system consists of an organic Rankine cycle and a hybrid GAX cycle, and uses a source of 100 kg low-temperature geothermal water at 133.3 °C to produce power and cooling at −50 °C. The ammonia-water mixture is used as the working fluid of the system. The “Parallel-Series” configuration of the system produces more power output, higher exergy efficiency, and lower unit product costs as compared to the “Parallel” configuration. For 1000 kW cooling load while other conditions are the same, the “Parallel-Series” configuration produces 1897 kW power with 42.8% exergy efficiency and 4.192 $/GJ total unit product cost. The exergo-economic analysis also shows that the boiler has the lowest exergetic factor, and the regenerator has the highest relative cost difference.