Refrigeration energy conservation

Mainly because of two factors, (1) energy conservation and cost and (2) the desirability of phasing out the use of chlorofluorccarbons (CFCs) in an attempt to slow the deterioration of Earth s ozone layer, refrigeration technology is under intense scrutiny as of the early 1990s. 

Insulation for process piping, vessels and equipment will be specified based on process energy conservation or personnel protection. Standard piping and fittings for steam, hot water, refrigerants, and instrument air will be utilized in most cases. 

Mathur, G. D. 2000. Carbon dioxide as an alternative refrigerant for automotive air conditioning systems, 371, 376. American Institute of Aeronautics and Astronautics AIAA-2000-2858. Energy Conservation Engineering Conference and Exhibit. 

American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) http //www.ashrae.org (accessed June 22, 2010). ASHRAE develops standards and guidelines in its field. The society addresses such areas as indoor air quality, thermal comfort, and energy conservation in buildings. 

Let me tell you how things were in the heady days of the late 1960s, when scientists (like me) and engineers first got their hands on computers. Computers were very large beasts, and they consumed very many kilojoules (kilocalories in those days, or if you are a North American reader) per unit time. If you believe in the law of conservation of energy, you will understand why such machines had a refrigeration plant, where the three resident engineers kept the milk for their coffee. 

For example a consumer wishes to buy a new refrigerator. The high-efficiency model (offering services identical to the standard model) costs 60 more but uses 400 kWh/year less electricity. The consumer expects to keep the refrigerator for ten years and has a discount rate of 5 percent. The cost of conserved energy in this case is calculated as follows ... 

A micro supply curve of conserved energy for a large commercial refrigerator. Each step represents a conservation measure. The numbers above the steps are keyed to the measure descriptions in the legend. Note that measures 1-4 are cost-effective because the cost of conserved energy is less than the energy price. If energy prices rise, then measures 6 and 7 may also become cost-effective. 

He is remembered for Joule s Law lhat describes the rale at which heal is produced by an electric current. Joule s work showed there were different kinds or energy, which can be changed into each other. He established the mechanical equivalence of heat. His work led to the law of conservation of energy. Alsu, he collaborated with William Thomson (Lord Kelvin) and verified experimentally the Joule-Thomson refrigeration effect. 

Before attempting to assess the likely future of thermodynamics in chemical engineering, it may be useful briefly to recall the past. In chemical engineering, the primary use of thermodynamics was, and still is, concerned with application of the first law (conservation equations), in particular, with energy balances that constitute an essential cornerstone of our discipline. Another primary use was, and still is, directed at description of fluid behavior, as in nozzles, heat engines, and refrigerators. The fundamentals of these important applications were extensively developed in the first third of this century. 

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