Problem of cold accumulation as a matter of energy saving and optimization of energy consumption

Abstract

It is shown that the problem of cold accumulation is complicated, and the importance of cold carriers, the temperature of generated and accumulated cold, methods of its utilization, and particularly for large users of cold, i.e., air cooling machines and vapor-compression refrigeration machines, are noted.The clearly defined problem of saving electrical energy and energy resources has stimulated specialists in very different fields to look not only for methods for reducing energy consumption, but also to develop storage and transforming electrical energy and heat, that will make it possible to optimize their generation and consumption. We are convinced that this also relates directly to low-potential heat, i.e., cold. Various aspects of this problem are still far from being studied in relation to the level of contemporary possibilities, although it has been realized for a long time in simple versions both abroad and in Russia, and in countries with a continental and warm climate.The main reasons for performing studies of this problem are, on one hand, a constant increase in the proportion of electrical energy for the purposes of generating cold, and, on the other hand, the existing difference in the costs of electrical energy during the day and at nighttime. The cost of 1 kW·h may vary by a factor of 1.5-4 (at night, the cost of electrical energy is less). In addition, the problem of accumulating cold has a direct relationship to the use of natural daily and seasonal changes in the temperature of thee environment with which potentially it is possible to provide a reduction in energy consumption for cold generation, i.e., to accomplish energy saving.Among objects that may be commercially suitable for using cold accumulation systems, it is possible to note large refrigeration stores, sporting structures, large objects of air conditioning, heavy-load ships, and also objects of large tonnage production and consumers of liquefied natural gas (LNG). Everyday refrigeration technology and climate technology also may be considered as objects for using these accumulators. The necessary control of electrical energy consumption during the day and at night is entirely real: so-called two tariff networks for electrical energy are already used, most extensively in newly built homes. In addition, especially under conditions of the northern latitudes, it is possible to realize pre-cooling of natural cold accumulators (water ice, etc.) with their further use for other purposes, including generation of lower temperature cold, for example, in natural gas liquefaction.It is clear that the problem of cold accumulation is complicated and there are important technical questions relating to the possible cold carrier, the temperature of generated and accumulated cold, methods of its utilization, and what is particularly important for large cold consumers, i.e., refrigeration machines for generating cold.We analyze the technical side of the problem of cold accumulation in fact for its large consumers in the field of moderately low and cryo...

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