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What's cheaper? Ice or Air Conditioning?

  1. Oct 6, 2011 #1
    No, not talking about putting a chunk of ice in front of a fan!

    My father remarked this afternoon, "all that ice you make uses a lot of electricity!" I put ice in my drinks, drink it all down, and my icemaker only makes what it needs. When it's full, it stops. His recommendation was to use less ice and save some bucks.


    I know that it's not a zero-sum game, that if I make a cube then let it melt the overall heat level in the apartment will be higher than if I'd not made a cube. There's losses in the refrigeration process, and those appear as heat.

    In the summertime, not so good. In the winter, however, does it make a hill of beans bit of difference? Is the heat waste in the icemaking process that much more expensive than the heat generated by the gas furnace?

    On the other hand, if I've always got an iced drink in hand, I don't turn down my A/C so much. In effect, it's targeted cooling, namely me. Instead of cooling the whole place (expensive) I'm only cooling me. Well, a mix of that, anyway.

    And during the winter, I'm likely to throw on a fleece sweater rather than turn up the heat. I like warm clothes, not a warm, dry environment. It's one of the reasons I moved here!
  2. jcsd
  3. Oct 6, 2011 #2


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    Keep your freezer full of frozen items and it will use less energy, that will offset the icemaker. :tongue2:
  4. Oct 6, 2011 #3


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    Yes! In the off-season, my wife and I store bags of ice in our freezers. We need the room now (harvest), but the ice is handy to have during the growing season when we're likely to have cookouts.
  5. Oct 6, 2011 #4


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    Typically, gas costs about 1/3 as much as electricity for equivalent amounts of heat.
  6. Oct 6, 2011 #5
    Or do what I do.

    As sensitive as I've been to heat all my life (and I nearly died from heat a few summers ago), I found, when I was living in the neighborhood of Inwood in Upper Manhattan (just how "upper" can be gauged by the fact that my living-room window looked out upon 215th Street, which is a street number so high that not that many Manhattanites are even aware that it exists within the Borough of Manhattan) during the Upper Manhattan Blackout of July, 1999, which deprived me of the benefit of a fan (Inwood being an old Working Class (NO snickering here, as I'm an ultra-proud (even downright chauvinistic) son of the Working Class myself) neighborhood which had historically hosted (give me an "A" for alliteration on that one!) the workers for the Upper Manhattan Subway Yards), I learned that just acclimating myself to the heat was the best defense against it.

    This did involve certain complications, as, during this period, I found myself convulsively shivering while working in the air-conditioned offices of the "White-Shoe" (technically, AV-rated) midtown Manhattan law firm which then employed me.

    And the frozen-food-in-the-freezer thing didn't work under the extreme conditions of that time and place, as my painter girlfriend's oil paint palates collapsed and intermixed as the frozen foods they were anchored upon melted due to the extreme heat. And, during this period, I was constantly bothered by the smell of the oil-based paints of her paintings hanging on the walls as they melted (not visibly, but odorously) due to the extreme heat.

    Which brings to mind the only episode of the old "Twilight Zone" television series whose original broadcast I actually recall from my childhood, an episode entitled "Midnight Sun", whose final scene shows a New York City-based female painter's paintings melting in the
    heat. Isn't that funny?
  7. Oct 6, 2011 #6


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    In one sense, I'm sure this is true. Every time you open the freezer door, practically all of the cold air is replaced with warm air that has to be cooled. If the freezer's full of food, it's only going to absorb a little bit of heat at the front and top of the food. The food buried in the back won't immediately absorb any heat at all. In other words, a full freezer takes in less heat to be removed.

    You still have to remove the heat from all of that stuff in the first place. Of course, if you're buying frozen foods, it probably hasn't absorbed a lot of heat just in traveling from the store to the house, so the advantage you're gaining is that someone else removed the heat instead of you before you filled up all the airspace in the freezer with your stuff.

    That wouldn't apply to ice that you freeze yourself, though. You're paying once to remove all of that initial heat in the first place and then barely nothing to keep it cold (provided you have a full freezer, don't open the freezer often, etc. But the fact that you're paying to remove all of that initial heat means keeping a freezer full of full ice trays isn't going to save you much.

    Considering it's something that you would pay to freeze anyway and that you actually plan to use means you might save a tiny bit over having nothing in your freezer besides a single ice tray that you refill over and over, but it wouldn't be worth freezing ice for the sole purpose of keeping a full freezer.

    And if you're freezing things because they need to be kept cold, the fact that electricity is more expensive than gas is irrelevant. It's essentially a little bit of 'free' heat in the winter and some extra cost in the summer (if you have A/C).
  8. Oct 6, 2011 #7


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    But I never said to freeze ice to keep the freezer cold.
  9. Oct 6, 2011 #8


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    From my experience with temperature controlled lab freezers, more mass means better stability.
  10. Oct 6, 2011 #9
    Maybe you should have!

    That would convert your modern mechanical freezer into an old-timey icebox.

    Which device actually worked!

    (My Inwood girlfriend had a freezer remarkably empty of anything except for a few boxes of frozen vegetables upon which she laid her oil-paint palettes. And that arrangement failed absolutely in the face of power-outage-versus-extreme-heat conditions.)
  11. Oct 6, 2011 #10


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    Speeking of frozen food, I lost mine in the move. Just a few last items today, but cannot find them to save my life. I was handing them to evo child, who should have been placing them in a box to be walked right over to the new freezer. She doesn't remember.
  12. Oct 7, 2011 #11
    Good reply - thanks!

    From what I understand, if my freezer is nearly empty, just putting an inflated garbage bag in it would displace the air. However, there's more to the reason as to why a full freezer uses less electricity than an empty one. It's about thermal mass. It takes longer to cool a full freezer from, say, 20 deg to 15 deg than for an empty one, but it stays cooler longer, too. The point is that the compressor's first few seconds are spent building up the pressure. Short compressor cycles are less efficient because those seconds are more frequent.
  13. Oct 7, 2011 #12


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    Your expectations for young people are too high.

    And so are young people.
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