One thing that has always bothered me is that refrigeration systems use up so much energy. Think about it. The purpose of a refrigerator is to remove heat from food. Heat is energy. Therefore, if you were to follow the train of logic, a refrigerator uses energy in order to remove energy from food and drink. This seems to be a tremendous waste to me. Surely there is some way that a refrigerator could be redesigned so that it saves the energy it removes from food. The same applies to freezers and air conditioning units - both are machines that remove energy in the form of heat at the cost of large amounts of energy. I know it's not as simple as that, but consider the logistics. According to the U.S. Energy Information Administration, in 2005, 91.4 million U.S. household utilized a sort of air-conditioning system (http://www.eia.doe.gov/emeu/recs/recs2005/c&e/detailed_tables2005c&e.html). Even if it is assumed that each of these households has only a single, medium-sized window unit, the cost of KiloWatts/hour is stabilized at 15 cents, and the unit is run for 16 hours a day, each household is still paying $804 per year. Multiply that number by 91.4 million, and you have an extremely conservative $73,485,600,000 per year spent by households on air conditioning. That's air-conditioning alone, not counting heating, refrigerators, or freezers. This number also doesn't include the amount spent on cooling businesses or public places.
By request, and via procrastination. Well, from the little bit I've learned about thermodynamics, the problem concerning the amount of energy to keep food cool is that the heat from the outside flows into the system that is trying to keep food cool. The items(air,frozen ice,milk,food) in the refrigerator cool down and help to stabilize the temperature, but the warmer temperature outside the system will always contribute to the cost of energy required to keep the temperature in the same spot. Basically, how a fridge works is that the required energy put into it all goes to the compressor where it heats up a gas by pressurizing it and then moves it to the lower pressure located in the coils in which the energy (in the form of heat)is transferred to the gas in an endothermic process. You may ask for higher efficiency in that part of the refrigerator, but the loss of energy again falls back on how much heat is let into the volume of the refrigerator. A design of an efficient "closed" system would reduce the energy required to keep it stabilized. Perhaps the construction of the refrigerator can have better insulation methods which then could lead to longer time in between cycles. Other ways could be location in cool spots of houses and possibly venting in cool air from the outside during cold seasons since we tend to keep our houses warm.
ReplyDeleteI've also been considering applying the technology of vacuums to refrigeration/climate control systems. I'm planning on doing a post on it in a few days. Thanks for your input.
ReplyDeleteAlso, I may have been somewhat unclear as to what my main premise is. I'm primarily concerned with the fact that it costs energy to remove energy from a system. It seems to me that the heat of the food, or even the outside air, could be gathered and converted into another form of energy. I don't know as of yet by what method this could be accomplished, but theoretically it seems plausible.
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