Tech-economic analysis of liquid air energy storage - A promising role for carbon neutrality in China

Abstract

Liquid air energy storage (LAES), a green novel large-scale energy storage technology, is getting popular under the promotion of carbon neutrality in China. However, the low round trip efficiency of LAES (~50 %) has curtailed its commercialization prospects. Limited research is conducted about the economic analysis, especially on the end-user side, as some national electricity policies may be friendly to the development of LAES. Therefore, a practical LAES system with 100 MW peak electricity output and a 501 MW heating supply is proposed. A typical example system built in Huitong District, Hebei Province, is given. The simple payback period and dynamic payback period are respectively 10.4 years and 6.5 years, while the levelized cost of storage is 0.11 $/kWh and the levelized cost of energy is 0.32 $/kWh. The subsequent economic analyses show that the payback period of the LAES system at the end-user side can be reduced by half compared to the LAES system at the power grid dispatching side, owing to its diversified incomes. There is an optimal peak regulation depth of 20 % in the thermal/renewable power plants integrated with LAES under the effects of the national electricity price policies. Finally, the potential carbon-emission economy of LAES should be taken seriously, particularly in the likely event that the carbon trading market is established. Among the four typical provinces in China, Hubei Province stands out with possible earnings of 0.07–0.074 $M/year, attributed to the sound carbon-emission basis and policies. Overall, the study provides a profound understanding of the application forms of LAES with the assistance of Chinese government policies, which will be vital for the development of energy storage technologies in the future.