Cold energy

The aim of heat recovery is to avoid wastage of any quantity of heat or cold energy which has been generated within a system. Methods of recovery may be passive or active. Mechanical heat recovery systems will generally be found under the description of Heat Pumps. 

Suzuki, T., S. Kobayashi, K. Tsushima, S. Shao, Y. Teng, and G. Liu, 1997. A case study on the utilization of snow and ice as natural cold energy source for low-temperature storage materials, Snow Engineering, pp. 553-558, ISBN 90 5410 865 7. 

Figure 215. Variation of air conditioner load indicates that almost all diurnal cooling load can be covered by stored cold energy in the nighttime...

The LPG cold utilization considerations are similar to those of LNG. The amoimt of cold energy, however, is smaller, especially with butane. Depending on the mix... 

P. Wang and T.S. Chung. (2012). A conceptual demonstration of freeze desahnation-membrane distillation (FD-MD) hybrid desalination process utilizing liquefied natural gas (LNG) cold energy. Water Res. 46 4037-4052. 

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