Introduction: Mini Solar Air-Conditioner (a.k.a Swamp Cooler)

Picture of Mini Solar Air-Conditioner (a.k.a Swamp Cooler)

Here's an Instructable to make a simple, cheap, and energy efficient air conditioner with basic materials, and should cost less than $5. How it works is evaporating water in the
A/C (air-conditioner) pulls heat away, making the inside cold. The fan sucks air through the A/C, making the air cold. The warmer it gets, the more effective this A/C gets.
And it's easy on your wallet!

The materials are:
-popsicle sticks (about 20)
-cooling fan from computer
-solar panel, batteries, or other low voltage power source
-cloth that absorbs well
-hot glue and a glue gun

Step 1: Cooling Fan... Meet the Popsicle Sticks.

Picture of Cooling Fan... Meet the Popsicle Sticks.

You can get cooling fans free from computer repair shops and are in power supplies.
Once you find a suitable one (bigger ther better), stick six popsicle stick like the picture below.
You can trim the round ends with scissors if you want.

Step 2: Dress Up Time!

Picture of Dress Up Time!

Now cut a few strips of the cloth that absorbs well (shamwow, towel, burlap...) like one of the pictures below Then cut using scissors four or more popsicle sticks so it's the same size as the base width . Glue the cloth strips onto the cut popsicle sticks. Then glue that on like the main pic. Attach another stick on the opposite side and glue the cloth onto it. The bottom pictures are examples.

Step 3: Dress Up Some More!

Picture of Dress Up Some More!

Glue another of these together (pic on the bottom). Then stick two popsicle sticks together like the two back ones on the first step. Glue it on like the pic shows and put another stick that's the base width size onto the other side. Streach the cloth across and attach it to the stick.

Step 4: Coveralls

Picture of Coveralls

If you have any extra cloth left, glue that on the sides. Remember: the more cloth, the better if there's easy airflow around everything.

Step 5: The End

Picture of The End

That was the Mini Solar A/C! Ugly but works. Add water to the cloth with a spoon until it's all soaked up, power it up with a solar panel (one or two watts), batteries, or a low voltage power source, and cool your house. Make several of these or a large scale one to lower your power bill in the summer.
Check out my other ible' for electric fire.


kamhagh (author)2016-07-12

Does this eve cool the room for a single degree ?:D

I currently use a bucket of ice, a hole in mid, fan to push air in in top ice in middle

water drops to the bottom. The air is 11 degrees but it's so small, Instead of a 80mm fan I might add a case fan but I'm too lazy to go buy a fan :D

weiw4 (author)2016-05-15

what is the specification for this mini solar air conditioner?

Thunder Power (author)2016-05-02

Hmmm better

GaneshP8 (author)2015-12-13

its fabulous and solve my problem of mini model

nice work dude

dakota_woman (author)2015-08-22

It's solar-powered, so is low voltage & low current - why not just put the cooler fabric on so it wicks water & set it in a pan of water & let 'r rip? I put 1 in the pickup cab for the dog, (YES, takosjza, WITH shades & sliders, windows & vents open, in the shade...), in a suitable box, running off the lighter jack. Works better than the old system of a fan and a pan of ice water - he would drink the ice water, leaving just the fan, which was ok but not as good.

Jimmeh30 (author)2015-08-18

Good idea if you want to learn the principle of evaporative cooling, but seriously, what's that fan going to move? 3 cubic foot an hour? even three cubes a minute. It might cool a washing machine box 3 or 4 deg, but it ain't going to do much for your bedroom.

saurezz (author)2014-07-02

can i get its lab report? like the mechanism it works on

wkahlich (author)2011-10-01

how do you connect the fan from a power source? i pulled one out of an old computer(laptop) and the connecter is just a white plug....

ANDY! (author)wkahlich2011-10-02

If there are two wires, Try putting a battery on them and switch the polarities if it doesn't work the first time. Good luck!

wkahlich (author)ANDY!2011-10-04

what should i do if there are three :) there is one yellow one black and one red

ANDY! (author)wkahlich2011-10-05

I am going to suppose the red is + and the black is -.
The yellow wire is a ground or something. You don't need to wire it to anything but you can attach it to the black wire if you want. Good luck!

The SYNer (author)ANDY!2013-06-24

Computer fans with 3 wires are usually digitally controlled. That third wire is where the motherboard sends its signal to tell the fan how fast to spin. Yay adaptive cooling!

chuanlu (author)wkahlich2012-07-22

Just keep rotating the wires thru the various possible pairings. You won't hurt the motor or yourself. Experimentation is the best way to learn. :-)

casey321b (author)wkahlich2011-11-14

5v is what you need. If you're not too handy with electronics, try using 3 AA batteries, and attaching them to it in a linear sequence..
Batteries should look like [+||||||||||-][+||||||||||-][+||||||||||-]
It should say on the battery, but the positive end is the one with the nub, and the negative is the one without it. Make sure the ends are touching and using some packing or duct tape to keep them together. Then, use some wire to connect it to the fan. It should have two or three wires on it. Red or white are positive, and black is negative. If there is a third wire, like you said in the other post, it is ground. Those are typically green, or in your case, yellow.
Ignore that wire.
It should work when you attach the wires. If you would want it to be more powerful, you can most likely use four AA batteries to get 6 volts. It will be fine. Don't use any more than that, though.

Faquad (author)2010-06-08

does the fan blow UP or DOWN into the cloth?

ANDY! (author)Faquad2010-06-16

down, where ever the cloth is

paqrat (author)ANDY!2012-07-24

Wouldn't this work better if the fan pulled air through the cloth? You'd have to seal everything offso the air was being drawn through the cloth. Also if you used a highly absorbant fabric and placed the ends of it in a pan of water wouldn't it tend to keep itself wet as long as there was water for it to soak up? To those who say this type of cooler won't work in high humidity I would mention that here, in Louisiana, we have high humidity most of the time and, before the advent of the air conditioners that use freon, evaporative cooling was used extensively. In some older towns you may still see the cooling towers on top of some of the buildings. Of course it was not as efficient as the freon type but it was all that was available and it made a huge difference from the outside, un-airconditioned air.

ANDY! (author)paqrat2012-07-30

Pushing air through works much better. Try blowing something over by exhaling, and then try to knock it over by inhaling. Which is easier?

solpredator (author)2011-05-23

There is a company right now selling "water making" machines that work best in hot, dry climates. I don't fully understand how it works yet (currently studying it) but am wanting to design my own version of this for home use. I live in Florida (Gulf-side) and from what I can see this machine would work here too.
I know it has something to do with De-humidifier and air conditioning condensation. I'm not soliciting info from other users or selling this product, just wanting to stir up some interest in our community for different design builds and open-source instructions for such a thing. ;)

ZPritz (author)solpredator2012-03-15

The only problem with that type of cooling unit is that it requires the hot dry air to evaporate the water in your system. Sometimes those units use a corrugated material that absorbs water. Air passes through the holes in it and that air evaporates the water soaked into it. The water that is evaporating cools the air passing through.

I was in the USCG at a small boat station on Fort Myers Beach. We tried this type of cooler when turning wrenches in the hot engine room. Only problem was that with the HIGH humidity on the gulf coast, the cooling effect was minimal at best. Basically we used it as a $600 fan. These evaporative coolers wont work when the humidity is high (which is about 90% of the time on the Florida Gulf Coast).

Hope that helps!

ugv7821 (author)solpredator2011-10-08

Sounds cool, I´ll try to find some info and come back :)

Necis (author)2009-05-05

Nice and simple, even though its more like a swamp cooler then a Air Conditioner. Seeing as I'm in the middle east at the moment and its starting to get hot I am probably going make a couple of these and see about tweaking it a bit. I'll let you know what I come up with

radiochemist (author)Necis2009-05-07

I made something similar using 2 thermal electric coolers hooked up to a 6 volt lantern battery instead of cloth. If you can get any of those and the heat sinks to go with them I would highly recommend it, it works pretty well to keep the heat and electricity bill down.

That sounds like it wouldn't work too well because peltier elements have a hot and a cold side. You have a fan hooked to a heatsink on the cold side and a heatsink on the hot side, the heat would radiate away from the hot side to be then absorbed by the cold side again so to make it work you would have to have the hot side outside to be able to cool.

I had it so that it was lying flat and the cold side was up, the hot side was in a project box with a fan blowing on a good sized heat sink, and a larger fan blowing on the cold side. It doesn't cool the room, it makes you feel cooler by blowing a cold wind on your face. you can also use a water cooling system for a computer

I hope that you realize the net gain of this system is an overall heat GAIN. Unless you go to great lengths to route the hot portion away, this is not a very swell idea.

Not so...because of the latent heat of vaporization. It takes a lot of energy to transform 212 degree water to 212 degree steam. So, how this system works is by removing that heat energy from the air and transferring it to the water. As the water evaporates, it utilizes the latent heat as it changes from a liquid to a gas - the water remains at the same temperature, but contains more energy.

Radiochemist's idea had no vaporization, though! Unless I am missing something.

Nope...Sorry...I missed something.

Howard, you should have stuck to your guns, you were 100% correct the first time. Just because water isn't at 212 degrees doesn't mean it can't evaporate...did you ever hear of the law of partial pressure? As long as the humidity in the air is less then 100% (which it usually is), water can be made to evaporate into it, and in doing so, absorb a lot of heat. That's what a swamp cooler IS. I don't think this mini cooler will do much to affect the temp of an entire house, but if you park it near you and point the airflow at you, it could easily make quite a difference in how comfortable you feel. That's subject to having DRY heat, as opposed to WET heat. If the humidity is high it won't work as well, but in most places it should work very well. Good going ANDY! But quit shouting, geez.

Okay, I just noticed this is under radiochemist's post, not the original author's. Sounds like we're all on the same page, sorry. :-)

radiochemist (author)HowardParr2009-05-14

yeah you're right, after a while they don't work so well, and I never said it works as good or better than an air conditioner, but it works and it's better than nothing. water works pretty well for storing heat, so you can not only use it to heat a room, if you have a mini heat pump such as a TEC you can use water to cool a room as well. since one side of the TEC is cold, and the fan is blowing over the cold side, it basically sucks any available heat in a room and concentrates it to the other side of the TEC, and the heat is absorbed and stored in the water. When the temperatures of the water and the hot side of the TEC become closer in temperature, the less effective it gets. That's why I say to have a few of them so you can cycle them and let the heat dissipate outside while having a solar panel recharge the battery. I'll make an instructable for it when I get a chance.

ANDY! (author)radiochemist2009-06-03

Tell me if you do.

ANDY! (author)radiochemist2009-05-15

I heard of that but it said it was sorta inefficient

ANDY! (author)Necis2009-05-14

ANy thing yet?

Necis (author)ANDY!2009-05-14

no nothing yet, trying to find the right material to make the stand. I got lots of old crates laying around, but no wood working tools. I might have to weld something together.

ANDY! (author)Necis2009-05-15

I need some more people to vote for me. I am a kid too so I am impressed how well I did. Really.

ANDY! (author)Necis2009-05-15

cool. try using the two crates on top of each other and stick cloth or smth on the sides. then stick a fan on a hole

cd41 (author)Necis2009-05-05

If you don't mind me asking, what brings you there? Best of luck with your tweaking...

teenuvibhav (author)2011-07-15

Verry Good EXP. I like your exepiriment verry much.

jignesh shah (author)2010-09-05

does this thing work in humid areas, in mumbai we have more than 85% humidity all round the year so it's importamt to know .can anyone please inform me.

Swix (author)jignesh shah2011-07-14

no it wont work for you... humidity must less then 50% because of evaporation try to make one like mine:

Hibiscus (author)2011-07-13

I personally add a small amount of detergent to the water before soaking the cloth. Then the breeze is not only cooler, but it is also fresher smelling!

MadScientist101 (author)2011-03-01

is there a more effective way or is using clothe the best?

ANDY! (author)MadScientist1012011-03-13

I'm not sure, maybe something with a lot of surface area.

msageng (author)2010-11-22

Determining the effectiveness of evaporative cooling systems is quite simple. Psychrometrics is the study of moist air interactions, and simple calculations will allow you to determine operating characteristics over a range of condtions. The wet-bulb temperature determines the effectiveness of evaporative cooling. Effectiveness is negatively correlated with wet-bulb; as wet bulb increases, the achievable temperature drop decreases.

Using a thermometer and hygrometer, determine the temperature and relative humidity of the ambient air feeding into the cooler. Find a psychrometrics calculator or chart (like ASHRAE #1) online and use it to determine the wet-bulb temperature. You'll likely see a temperature drop of 50-75% of the wet bulb depression.

These don't work well in humid climates (coastal areas, especially). In the southern U.S. where cooling design conditions are in the range of 95 F (dry bulb) with a coincident wet bulb temperature of 77 F, the theoretical best you could achieve would be 77 F, but is usually in the range of 80 F, depending on the cooling efficiency of the system. I'd suspect that this system would be quite inefficient, owing to the ill-defined flow paths and heat gain from the fan motor.

Dr.Bill (author)2009-05-14

Ya did alright Andy. Ya got the right idea. I saw one of these on a much larger scale being used to keep food refridgerated and right now mine is keeping me nicely refridgerated.

beehard44 (author)Dr.Bill2010-10-24

terra cotta beverage cooler...
i built one before

diylover_1234 (author)2009-05-29

I made this entire thing and I used hot glue and after about 2 hours the whole thing fell apart. DON'T USE HOT GLUE!!!!

NinjaJay (author)diylover_12342009-07-10

Just an aside about hot glue--after various little projects, I've concluded that silicone (as purchased in a caulking tube for ~ $2) is far superior glue to hot glue. Yes, hot glue goes on fast, but the big drawbacks are: 1) pain, and 2) it rarely holds.
Give silicone a try. It generally dries to a workable hold in a couple hours, completely in 24 hrs (probably overstating drying times). Another nice thing about a tube of silicone is that, even if you leave half a tube sitting for months, only the tip is dried out. Give a squeeze to the caulk gun, and it comes flowing again.

About This Instructable



Bio: i like ice-cream.
More by ANDY!:Paper UkuleleLMFAO Robot/Shufflebot HeadThe Incredible Paper Canoe
Add instructable to: