A novel liquefied air energy storage system with solar energy and coupled Rankine cycle and seawater desalination

Abstract

To improve the round-trip efficiency of liquefied air energy storage (LAES) system by energy cascade utilization, a novel LAES system with solar energy and coupled Rankine cycle and seawater desalination is proposed. The thermodynamic model of the coupled system is established, and the technical advantages of the coupled system are investigated in four aspects: system energy efficiency, exergy efficiency, round-trip efficiency, and desalination. The results show that the highest system energy efficiency and exergy efficiency are 33.57 % and 44.34 %, respectively. When the system is coupled to Rankine cycle, the maximum system energy efficiency can be improved by 6.01 %, and the maximum system exergy efficiency can be improved by 9.24 %. The round-trip efficiency of the system can reach up to 132.20 %, which is 26.87 % higher than the LAES system with only solar collector panels. Furthermore, the system can produce up to 7079.51 kg of fresh water per hour and achieve a maximum water production ratio of 6.61. The coupling of solar energy, Rankine cycle and desalination can not only improve the efficiency of LAES, but also provide a new idea for the promotion and application of LAES.