# How Do You Make Ice With ONLY a cooling tower and no refrigeration machinery"
**URL:** https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487
**Category:** Factual Questions
**Created:** [March 22, 2006, 9:49pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487 "2006-03-22T21:49:10Z")
**Posts on this page:** 8
**Page:** 1
### Author:  [@spingears](https://boards.straightdope.com/u/spingears)
#### Post date: [March 22, 2006, 9:49pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487/1 "2006-03-22T21:49:10Z")
[Aussie John Recalled](http://boards.straightdope.com/sdmb/showthread.php?p=7222513#post7222513)
> [@AussieJohn](#):
>
> I remember the ice in hot Australian country towns in summer coming from icehouses which used evaporative cooling wooden water towers to make the ice. It seemed to work very well, with the water cascading down the outside.
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### Author:  [@silenus](https://boards.straightdope.com/u/silenus)
#### Post date: [March 22, 2006, 10:18pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487/2 "2006-03-22T22:18:28Z")
_Cooling drinks was popular particularly in Europe’s southern climates, especially Italy and Spain. It became en vogue by 1600 in France. By this time, instead of cooling water at night, people rotated long-necked bottles in water in which saltpeter was dissolved. This solution, it was discovered, could be used to produce very low temperatures and to make ice. By the end of the 17th century, iced liquors and frozen juices were popular in French society._
From [here](http://www.history-magazine.com/refrig.html).
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### Author:  [@Lumpy](https://boards.straightdope.com/u/Lumpy)
#### Post date: [March 22, 2006, 11:38pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487/3 "2006-03-22T23:38:20Z")
I read that but it didn’t make a lot of sense. Does saltpeter absorb heat when the solid form is dissolved in water, enough to reach 0 centrigrade? While in theory it takes some heat energy to change a solid to a liquid, most substances that I’ve heard of that dissolve in water have such a potential that they generally produce heat when dissolved, not absorb it.
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### Author:  [@Sal\_Ammoniac](https://boards.straightdope.com/u/Sal_Ammoniac)
#### Post date: [March 23, 2006, 2:30pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487/4 "2006-03-23T14:30:53Z")
I’m bumping this, because it’s piqued my curiosity, and I’m convinced someone has a good answer. Anyone?
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### Author:  [@Sunspace](https://boards.straightdope.com/u/Sunspace)
#### Post date: [March 23, 2006, 4:11pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487/5 "2006-03-23T16:11:54Z")
:: dim memories of architecture school ::
I seem to remember that there were two things: radiative cooling and evaporative cooling.
In radiative cooling, objects lose heat to the night sky. In some sheltered conditions, water could lose enough heat to the night sky to freeze, even if the air temperature was a few degrees above freezing.
In evaporative cooling, you would moisten a towel and let the water evaporate, cooling the air around it as the water absorbed the heat of vaporisation. This required dry conditions and plenty of water, though.
Perhaps the cooling towers used these principles. Or perhaps they were as simple as thermal mass, cooled by outside air during the night, and used to cool air entering the room during the day.
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### Author:  [@stuyguy](https://boards.straightdope.com/u/stuyguy)
#### Post date: [March 23, 2006, 4:22pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487/6 "2006-03-23T16:22:01Z")
We had a thread about this a few years back. It mentioned how Arabs would make ice in the desert using the night sky method. I had a college physics prof. who once mentioned this technique, and I thought he was bonkers until I read that thread. Try searching for it. It had some good links too, IIRC.
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### Author:  [@parabolis](https://boards.straightdope.com/u/parabolis)
#### Post date: [March 23, 2006, 4:35pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487/7 "2006-03-23T16:35:48Z")
> [@Aussie John](#):
>
> evaporative cooling wooden water towers to make the ice
It seems that [evaporative cooling](http://en.wikipedia.org/wiki/Evaporative_cooling) towers are also known as [swamp coolers](http://en.wikipedia.org/wiki/Swamp_cooler). They are [still in use](http://www.air-n-water.com/faq_swamp.htm) today because they are very effective in very hot dry environments – which accurately describes much of rural Australia. Wikipedia says a modern residential swamp cooler can only cool air down to 60 °F on a 90 °F with 15% relative humidity. So even taking into consideration things like the [Mpemba effect](http://en.wikipedia.org/wiki/Water_%28molecule%29#Mpemba_effect) it seems very unlikely that Aussie John was remembering anything besides a water tower which kept already frozen ice from melting.
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### Author:  [@stuyguy](https://boards.straightdope.com/u/stuyguy)
#### Post date: [March 23, 2006, 6:28pm UTC](https://boards.straightdope.com/t/how-do-you-make-ice-with-only-a-cooling-tower-and-no-refrigeration-machinery/349487/8 "2006-03-23T18:28:54Z")
Here, I found two old threads that might prove illuminating on this topic:
[Question on cooling things naturally with the night sky](http://boards.straightdope.com/sdmb/showthread.php?t=322103&highlight=Arabs+desert)
[Is there any way to refrigerate foods w/o electricity](http://boards.straightdope.com/sdmb/showthread.php?t=318735)