## 5 Conclusions  
A new LAES system with carbon capture for gas power plants was proposed. By utilizing the cold energy and exergy of LNG and decarbonized high pressure flue gas, H\({}_{2}\)O and CO\({}_{2}\) were condensed and removed. A reduction in CO\({}_{2}\) emissions and an improvement in electricity output can be achieved. This study investigated the effect of the charging pressure, air expansion stages, and electricity prices on the system performance with thermodynamic and economic analysis models. The main findings are presented as follows:  
* A charging pressure of 12 MPa was preferred for both thermodynamic and economic advantages. In this scenario, Case A had its highest net generation of 27,369 kW with an RTE of 47.72% and an ERTE of 69.74%. The equipment and material investment costs were calculated to be USD 28.44 and 2.55 million, respectively. The best outcome for Case A resulted in an SPC of 0.1855 kWh\({}_{e}\cdot\)k\({}_{\text{ELA}}\)\({}^{-1}\) and an LCOE of 0.0965 USD\(\cdot\)kWh\({}^{-1}\);
* A net power output of 27,291 kW was observed in Case B when the charging pressure was 12 MPa, giving an RTE of 47.58% and an ERTE of 69.91%. Benefiting from the cost reductions from the ATs and SHs, the equipment investment in Case B was USD 28.23 million, which was USD 209.98 thousand less than that in Case A. The SPC and LCOE for Case B were USD 0.1855 kWh\({}_{e}\cdot\)k\({}_{\text{ELA}}\)\({}^{-1}\) and 0.0967 USD\(\cdot\)kWh\({}^{-1}\), respectively, which were almost equal to those of Case A;
* The proposed system allowed for better access to price arbitrage. By operating the system with 8 h charging and 8 h discharging per day, while considering off-peak and on-peak electricity prices of 0.042 USD/kWh and 0.196 USD/kWh, respectively, the NPV was expected to be USD 88.8 million. An off-peak electricity price of 0.028 USD\(\cdot\)kWh\({}^{-1}\) and an on-peak electricity price of 0.196 USD\(\cdot\)kWh\({}^{-1}\) led to an attractive DPP of 3.46 years and an LCOE of 0.0802 USD\(\cdot\)kWh\({}^{-1}\);
* The viability of price arbitrage was constrained by the electricity price. The on-peak electricity price fell below 0.168 USD\(\cdot\)kWh\({}^{-1}\) and the off-peak price exceeded 0.070 USD\(\cdot\)kWh\({}^{-1}\), which meant that it did not reach good profitability for the allowed electricity market conditions. The DPP may exceed the specified time limit (20 years) and even fail to achieve a positive annual profit. Figure 10: Effect of the on-peak and off-peak electricity price on the DPP. Above all, the RTE and ERTE of the proposed system have been proven to be acceptable and have considerable potential for further development under the condition of sufficient economic benefits. The liquid propane tanks, air compressors, and air turbines will account for the main part of the initial investment costs. Based on this study, enhancing the recovery of exhausted heat and cold energy could lead to better electricity conversion efficiency and reduce investment costs. Conceptualization, X.Q. ; methodology, H.T. ; software, X.Q. and N.W. ; investigation, W.L. ; data curation, X.Q. ; writing--original draft preparation, X.Q. ; writing--review and editing, X.Q. and N.W. ; supervision, H.T. ; funding acquisition, H.T. All authors have read and agreed to the published version of the manuscript. The work was funded by the National Natural Science Foundation of China (Grant Number: 52076159). Not applicable. The authors declare no conflict of interest. _Appl.