In contrast to conventional temperature-controlled warehouses, which have vertical partitions in different temperature zones, the stratified storage system utilizes the different density (and therefore the different weight) of hot and cold air.
Cold air flows into the lower part of a store up to a predetermined height, where it is extracted and fed into an external air recirculation system. This allows different, horizontally arranged temperature zones to be formed in a warehouse. (Development and patent: Siemens AG/Production and Logistics Systems (PL) and Zander Klimatechnik AG).

Source: logipedia / Fraunhofer IML