Frugal Thermodymics Part II: A Simple Cooling System

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A Simple Cooling System

Heat naturally diffuses from areas of higher concentration to areas of lower concentration. And cold being the absence of energy, a block of ice literally draws heat out of the air.

As was mentioned in P. Pince’s recent article, our air conditioning system is on holiday at this inopportune time. While looking at cooling units online, I saw several that were merely refrigeration systems which fanned air over ice or cold water. These systems are meant for use in places with dry climates, and as we live in the desert which is just such a place, we thought we’d give it a try.

Instead of purchasing a new unit or repairing our old one, we decided to simply use containers of ice placed in front of fans in rooms where we’re working or hanging out. When the ice has melted and the water is near room temperature, we remove it and bring in a new one if still needed. We make the ice at night when it requires less electricity for the refrigerator to keep cold.

We also consider thawing frozen vegetables in our rooms prior to cooking, though I wouldn’t do this with meat or anything that might lead to food poisoning.

If your automatic ice maker is already cranking out heaps of ice faster than you can consume, take some out and let them melt. You could do the same with the ice from defrosting your freezer.

And with entropy in mind (a concept of energy flow), I believe it would be advantageous to bring home ice, ice cream, and cold items (cooled on someone else’s dollar) during the day rather than at night. The saving may be very small indeed, but we’d make poor misers if we dismissed an economization on account of smallness, wouldn’t we?

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4 thoughts on “Frugal Thermodymics Part II: A Simple Cooling System”

  1. Interesting idea, and an A for effort, but I guess I have my doubts on this. First, there’s going to be costs associated with the water to make the ice as well as the electricity for the ice maker to run. Second, most air conditioners work in part by removing humidity from the air. The plan that you’re outlining is opposite of that, adding additional humidity. I suspect that the short term comfort from the cooled ice could be negated in the long run by the additional humidity that you’re introducing.

  2. Perhaps we should have made it more clear.

    1) We put water in jugs and containers (family-size yogurt tubs with lids, gallon cooking oil bottle, quart-size soy sauce bottles, etc.) and freeze the jugs so we just put them back in the freezer at the end of the day when it’s cooler and it takes less energy to make ice. Therefore, we just reuse the same water and it doesn’t go to waste.

    2) This system – like the portable evaporative air cooler units (like this one) that use water or ice – works for dry climates such as the desert where we live. Humidity isn’t a problem for us – in fact, dryness is a problem here.

    3) If you have an ice maker in your fridge, which we’ve had before, we found that it always made more ice than we could personally consume. After sitting in the freezer a while, the ice would get freezer burn so it didn’t taste good in drinks anyway.

    This system may not work for everyone, but it has been working well for us so far. We’ve had temperatures over 100 in the last few days, but have been able to stay cool this way. Compared to the costs of running an air conditioner in this climate (as high as $400 a month some summers), this system is saving us a lot.

    Penelope Pince’s last blog post..What’s the silver lining in this recession?

  3. This will only work if it is significantly colder at night than during the day where you can open windows at night to cool your house. As you have physics at play why your freezer dumps all the heat from making the ice into the room it’s sitting in so if your windows are closed all the time then you are cooling the air that you just warmed by using the freezer… and seeing as there is significant energy losses in this system then it will only work in places like the desert where it drops 40-60 degrees day to night… places such as florida where it only changes like 5 degrees it’s a bad plan.

  4. 1) We do have the windows open when the air outside is cooler than in

    2) We do live in the desert where temperatures drop significantly at night

    3) We use this system to cool the rooms where we’re working or hanging out in – not the whole house

    Again, we’re not saying this system works for everyone. It’s a comparative system to the portable evaporative air cooler units, which some people can use depending on where they live.

    Our energy bill last month was $40 compared to the usual $150-$400 a month when we used to have the air conditioner running.

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