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Do any of you guys remember the old "BULLETS" that fit on top of a rolledup window glass in cars back in the 50s. You filled them with ice and then the air would be forced through them as you drove down the road. They never really worked but it made my dad feel better that he was trying. GB
 

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Homemade swamp cooler!

This seems to be a homemade version of a swamp cooler, a device used for cooling in dry areas is the west and southwest. They are placed on roofs with a vent into the house or into a window. They typically have a turbine type fan in them and you can feel the cool air all over the house. A swamp cooler moves enough air that anyone who uses one keeps a door or window open to allow for the incoming air to leave. Some people really like them and some do not. The cost to run one is pretty much the cost of running a house fan and the cost of the water you use in it.

Where I live, I bet more than half of homeowners cool their homes with swamp coolers. On the hottest of days we can put on a sweater or jacket if we run it on high all day.

While ice in the bucket may help with cooling, we just use water in our swamp coolers.

People who have lived in humid areas do not understand how a swamp cooler works. They equate humid with sticky and uncomfortable.
 

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Evaporative cooling can be great in non-humid climates, that's how sweat works after all:), using ice is a bit different but you would also be getting some evaporative cooling as well.
If you do a search on youtube or wherever there are some cool;) adaptations of this very simple principle. I saw this one most recently but there are others that may be more practical.
 

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Thank you Cowboyhermit! That would be a great option for an off grid situation or using a solar panel when there is no power.

This video shows how a typical swampcooler or evaporative cooler works. They are extremely easy to service. I installed my own, and have replaced the pads, pump, and other service to the cooler. Easy and straight forward!

 

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We will be building a shade room to the south (cool side) of our house. We'll put a few evaporative cooling pads along the western wall then pull cool air from this area to cool the house. This system works well here (dry summers) and the only power needed is fans to move the air into the house. We will be putting in a thermal chimney to pull air through some of the house but the building was not designed for easy air flow so we'll assist with small fans.
The link below shows the type of pad but the ones we will use will be a little less dense and are designed for passive air flow.

http://www.redpath.com.au/commercia.../greenhouse-fans/evaporative-pad-system.html€
 

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I remember the BULLETS; my Dad had one on his 1959 Lincoln. It worked pretty well on long trips, but sometimes a little water would blow through. :eek:
 

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I find it difficult to believe it would work. The amount of heat in the air is way too much to overcome by blowing air through a tiny amount of ice. You would need a way to melt the ice almost instantly using the heat from the room. At best it would make the air in the room too damp. At worst it wouldn't keep the room from heating up if you started using it early in the morning.
 

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He splices the fan and pump wires together, would the solar powered pump he links to, be able to run both?
NO. Read it again:
It uses about 1.45amps per hour. My 105AH deep cycle battery will run this cooler for 47 hours before needing to be recharged. So running 4 or 5 hours a day, it will let you nap in the hottest part of the day, all week without recharging the battery.
He/She doesn't say "how" the battery gets recharged.... but you won't do it with the solar panel that comes with any of those pumps. You would need a DECENT sized panel (5+ amps) to charge a 105 Ah battery, though! (and the author was probably letting the voltage get a little lower than they should have before recharging!)

The little solar panel that comes with the solar water pumps will help the battery from getting drawn down too quickly, though (IF the OCV is high enough). I don't think it would be enough to keep the battery "charged", but it would definitely help to make the setup run a little longer than it would have on just "battery only".
 

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Yep, it must be humid where you live!

I find it difficult to believe it would work. The amount of heat in the air is way too much to overcome by blowing air through a tiny amount of ice. You would need a way to melt the ice almost instantly using the heat from the room. At best it would make the air in the room too damp. At worst it wouldn't keep the room from heating up if you started using it early in the morning.
The people who doubt the effectiveness of an evaporative cooler live where it is humid. Hot AND humid is typically uncomfortable. Why in the world would so many people have swamp coolers if they did not work? As for this one in a bucket, we have to ask, who has tried one? How effective is it?

I have had small independent swamp coolers 3 times in my life and they made a difference. Certainly it is not the same as central air. In tough times, like a space heater, a room closed off could be much more comfortable than nothing.
 

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Evaporative cooling works quite well given the right setup.

For anyone interested, when one gallon of water evaporates it "absorbs" about 8000btu of heat, that heat is held within the structure of the molecules. The rate of evaporation will change in many ways, it is much easier to do in dry climates and more surface area will speed the cooling, airflow also help but these all change the rate of cooling not the amount that will happen to evaporate the water.

There are ways to utilize evaporative cooling without adding any moisture to the area you are cooling, actually they can even be used to dehumidify if condensation is caught off the heat exchange medium.

Also ice will absorb about 1200btu per gallon when turning to water if you go that route, plus the temperature difference you could be looking at close to 10 000btu per gallon.
 

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Y'all should note that "evaporative cooling" and "thermal transfer" (air over bowl of ice) are two completely different critters....
 

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Y'all should note that "evaporative cooling" and "thermal transfer" (air over bowl of ice) are two completely different critters....
Yeah, I hope my posts weren't misleading or confusing. It is hard/impossible to have the thermal transfer without the evaporation/melting though. Water absorbs a lot more heat when changing from liquid to gas than when changing from solid to liquid but they are both useful.
 
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