Thermodynamic analysis and economic assessment of a novel multi-generation liquid air energy storage system coupled with thermochemical energy storage and gas turbine combined cycle

Liquid air energy storage (LAES) is one of the most promising technologies to balance the demand and supply of electricity, which is attracting more and more researchers' attention, but the system's efficiency is still relatively low. To further improve the round trip efficiency (RTE) and energy utilization rate (EUR) of the LAES system, a novel LAES system coupled with thermochemical energy storage (TCES) and gas turbine combined cycle (GTCC) is proposed in this paper. In addition, based on the baseline liquid air energy storage (B-LAES) system, an improved liquid air energy storage (I-LAES) system is also proposed to utilize the excess air compression heat to produce cold energy or thermal energy under different operation modes. Thermodynamic analysis and economic assessment are performed to evaluate these three systems' performances. Compared with the B-LAES system and the I-LAES system, the LAES-TCES-GTCC system has the highest RTE of 123.07 % and the highest EUR of 88.74 %. The LAES-TCES-GTCC system also has the best economic feasibility, with a net present value of $24.08 million and a dynamic payback period of 7.29 years. For the novel LAES-TCES-GTCC system, enhancing the methanol decomposition pressure, direct normal irradiation, and mass flow of vapor all reduce the EUR. And the EUR reaches the maximum at an inlet air temperature of the throttle valve of -168 degrees C.

Automated summary

Liquid air energy storage (LAES) is a promising technology for balancing electricity demand and supply, but its efficiency is still relatively low. This study proposes a novel LAES system coupled with thermochemical energy storage (TCES) and gas turbine combined cycle (GTCC) to improve the system's round trip efficiency (RTE) and energy utilization rate (EUR). Thermodynamic analysis and economic assessment reveal that the LAES-TCES-GTCC system achieves the highest RTE (123.07%) and EUR (88.74%) compared to the baseline LAES (B-LAES) and improved LAES (I-LAES) systems. Furthermore, the LAES-TCES-GTCC system demonstrates the best economic feasibility with a net present value of $24.08 million and a dynamic payback period of 7.29 years.