Thermodynamic and economic comparison of novel parallel and serial combined cooling and power systems based on sCO₂ cycle

Based on the principle of cascade utilization of energy, the organic Rankine cycle (ORC) and the absorption refrigeration cycle (ARC) were adopted to recover the waste heat from supercritical CO₂ (sCO₂) cycle. By changing the configurations of ORC and ARC, two combined cooling and power (CCP) system were proposed: parallel system (PCCP) and serial system (SCCP). Besides, the control valves are introduced into both systems to control the seasonal operation of ARC. Meanwhile, the performance comparison was investigated in the aspects of thermodynamics and economy. The multi-objective optimization was carried out to maximize system exergy efficiency and minimize system unit cost. It can be observed that the SCCP presents a larger exergy efficiency of 62.62% and a cheaper equivalent unit cost of 5.60 $∙kWh⁻¹, which are 0.43% higher and 0.19 $∙kWh⁻¹ lower than that of the PCCP, respectively. However, the PCCP could generate an additional refrigeration capacity of 116.245 kW than SCCP when ARC operates. The SCCP is finally recommended due to a cheaper equivalent unit cost and a larger exergy efficiency.