Preliminary conceptual exploration about performance improvement on supercritical CO₂ power system via integrating with different absorption power generation systems

Supercritical CO₂ (sCO₂) power system has been investigated by many scholars due to its attractive advantages of higher efficiency, compact system structure and eco-friendly working fluid. In this paper, some preliminary conceptual exploration about performance improvement on sCO₂ power system by integrating with two types of absorption power generation (APG) systems are conducted. Parameter analysis, genetic algorithm (GA) optimization and exergy analysis are carried out quantitatively for the proposed combined sCO₂/APG systems based on the self-built simulation platform from the viewpoints of thermodynamics and economics. Parameter analysis results reveal that there exist optimal compressor pressure ratio to maximize the thermal efficiency or minimize the total product unit cost. Higher turbine inlet temperature and lower absorber temperature could contribute to the overall system performance. In addition, compared with the stand-alone sCO₂ system, improvements of 5.98% and 5.07% in thermodynamics as well as promotion of 4.24% and 2.19% in economics can be obtained for sCO₂/LiBr-H₂O system and sCO₂/ammonia water system, respectively. Furthermore, exergy analyses show that the main exergy destructions occur in the reactor and the cooler and the proposed combined sCO₂/APG system could effectively reduce around half of the exergy destruction within the cooler of the stand-alone sCO₂ system.