Using cheap, off-peak electricity, the CryoEnergy System pilot plant operates by extracting ambient air from the surrounding environment.

Rob Morgan chief technology officer at Highview, explains that the gas is cleaned, compressed and then cooled until it liquefies. Liquefied air is then stored in an insulated tank at -196° C.

Read more: http://www.plantengineer.org.uk/article/36698/Worlds-first-liquid-air-energy-storage-plant-uses-Atlas-Copco-.aspx