STORED CRYOGENIC REFRIGERATION

A holding chamber may be supplied from a storage vessel system with a cryogen, such as liquid CO2, or it may itself be large enough to take the place of a separate storage vessel. The temperature within the holding chamber is reduced to the triple point or below to form a refrigeration reservoir of solid cryogen, as by removing vapor from the chamber to cause evaporation or by employing mechanical refrigeration. The stored cooling power of the reservoir is later employed to meet a large or a periodic refrigeration demand and is thereafter replenished over a number of hours, preferably during a period of non-peak electric demand. This storage principle can be incorporated into a variety of different refrigeration systems. For example, a CO2 storage system may be used to produce and store solid CO2 during a period of low demand upon a coupled mechanical refrigeration system; thereafter, the solid CO2 is used to supplement the mechanical system during a high-demand period, thereby increasing the effective refrigeration capacity of the mechanical system.