The development of long-term energy storage is more important today than ever because intermittent renewable energy source, such as wind and solar photovoltaic are growing rapidly in power generation market. Therefore, the demand on a bulk storage system is expected to increase significantly as result of renewable energy policy. The compressed air energy storage and liquid air energy storage system are an innovative technology for commercial grid scale energy storage. Especially liquid air energy storage system is expected to overcome the drawbacks of pumped hydro storage and compressed air energy storage. The proposed system is a novel stand-alone LAES system to enhance Round-Trip Efficiency (RTE) using a sensible heat store of packed bed type and latent heat store unit. The cryogenic Phase Change Material (PCM) melts at 110K based on experimental result, making it possible to provide cold enerrgy at a constant temperature for air liquefaction. The analysis shows that the implementation of energy recycling from the compressor and cold thermal store leads to a high RTE than conventional LAES system.

Ju-Yeol Ryu received B.S degree in dept. Of mechanical eng. from Yeungnam University in 2010 and MSc in mechanical eng. from Sungkyunkwan University in 2021. He worked Samsung C&T Corporation for 6 years since 2010 as basic design process engineer. He is currently a senior researcher at Institute for Advanced Engineering(IAE). He research focues on long-term mechanical Energy Storage System(ESS) to supply power energy stably such as Liquid Air Energy Storage(LAES) and Compressed Air Energy Storage (CAES).