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.

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.

Jimmeh3017 days ago

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.

saurezz1 year ago

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

wkahlich3 years ago
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)  wkahlich3 years ago
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 ANDY!3 years ago
what should i do if there are three :) there is one yellow one black and one red
ANDY! (author)  wkahlich3 years ago
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 ANDY!2 years ago
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!
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. :-)
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.
Faquad5 years ago
does the fan blow UP or DOWN into the cloth?
ANDY! (author)  Faquad5 years ago
down, where ever the cloth is
paqrat ANDY!3 years ago
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)  paqrat3 years ago
Pushing air through works much better. Try blowing something over by exhaling, and then try to knock it over by inhaling. Which is easier?
solpredator4 years ago
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. ;)
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!
Sounds cool, I´ll try to find some info and come back :)
Necis6 years ago
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
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. :-)
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)  radiochemist6 years ago
Tell me if you do.
ANDY! (author)  radiochemist6 years ago
I heard of that but it said it was sorta inefficient
ANDY! (author)  Necis6 years ago
ANy thing yet?
Necis ANDY!6 years ago
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)  Necis6 years ago
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)  Necis6 years ago
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 Necis6 years ago
If you don't mind me asking, what brings you there? Best of luck with your tweaking...
teenuvibhav4 years ago
Verry Good EXP. I like your exepiriment verry much.
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.
no it wont work for you... humidity must less then 50% because of evaporation try to make one like mine: http://youtu.be/jla5s_A11Pc
Hibiscus4 years ago
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!
is there a more effective way or is using clothe the best?
ANDY! (author)  MadScientist1014 years ago
I'm not sure, maybe something with a lot of surface area.
msageng4 years ago
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.Bill6 years ago
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.
terra cotta beverage cooler...
i built one before
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!!!!
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.

dude are your projects very greasy? hot glue works! maybe you use the glue while the gun is not yet hot enough
ANDY! (author)  NinjaJay6 years ago
thanx. i have high quality hot glue. cost more
ANDY! (author)  diylover_12346 years ago
It did for me.
Looks cool! I wish I lived in a swamp!! Way to go, Andy!!!
ANDY! (author)  GlobalWarmingDoesntExist6 years ago
I know you Johnny.
How big an area will one of these cool? Will i have to replace the water? If so how often?Which direction do i put he blowing end of the fan?(up or down) How cool will it get? If I make more of these will the air get even cooler? I heard my parents say that swamp coolers are less eficient than regular acs? Is this true or is it because that one was old? Few sorry for the wall of questions i just had a lot of them...
not a big area use a slow drippier system of some sort down just a cool as the water is i don't know ? ? :)
By not a big area do you mean a few feet or maybe a yard?
maybe about 10-30cm square. i dont know the imperial system
yeah, metric is standardized all over the world although imperial is still used
ANDY! (author)  HisDivineShadow6 years ago
Just put more water if it dries out. It will get cool enough to be cool. Efficiency is better than ACs cause theres no heating needed.
ANDY! (author)  HisDivineShadow6 years ago
Depends how big you make it. Mine is too small to cool that much.
beehard444 years ago
i made the same thing except i used a plastic cup with a tissue core (fancy way of saying putting a roll of tissue in the center) it cools! which is weird here in the humid conditions of Philippines.
greenlife5 years ago
funny idea. we have solar air conditioner for sell. Solar Air Conditioner CE Certification Electricity-saving 60% to 70% in Summer Electricity-saving 30% to 40% in Winter Running at -5 to 53 celsius degree Superior to frequency conversion air conditioner Solar Air Conditiner Cooling only/cooling&heating O-zone friendly freon 1,High efficiently,energy-saving,comfortable and money saving. 2,Durable and long-lived,smooth running. 3,Low-loaded operation of the compressor to extend its duration. 4,Healthy and comfortable 5,It is not frequency conversion air conditioner but superior to it. 6,Super luxurious appearance 7,Automatic open and close dustproof air outlet. 8,Easy installation
how much is your solar air conditioner Is this actualy an air conditioner or a swamp cooler
our solar air conditioner is actully air conditioner
ANDY! (author)  greenlife5 years ago
are you going to give me credit and royalty? ;)
gafar musa5 years ago
very interesting,i av bn lookin for some like this. i will try to build min.cooooool
It doesnt really make sense. I understand that evaporating water will draw heat away, which is why you sweat. The only problem is that the evaporated water absorbed the heat, and now the warmed, evaporated water is blowing into the air. Not only will this actually make it warmer, but humidity makes air feel warmer. If I am wrong, please correct me, but that is how I understand it.
ANDY! (author)  zvillesurfer6 years ago
I dont think, If you want proof, go to a local lake and dunk your self in it. Clod aint it, the wonders of evaporating. Also water vapor just floats away. It works for me though the A/c.
Well the heat has to go somewhere, and it is my understanding that the water vapor would absorb the heat, and since it's just being blown back into the air, it's counterproductive. It would only work if the water vapor was directed outside.
Hey, check my reply at the top. Might clarify things a bit for you...
Ahh yes. Thank you. A gas can have a higher energy state without actually being hotter. That was the piece of information I was missing. I've only had an intro to thermodynamics in physics class, so i was just trying to figure it out.
Yeah, its like 32 F water and 32 F ice. The only thing different is about 900 BTU in energy per pound or roughly 300 watts.
  I have to agree. I live in Florida where it is VERY humid, often 80-90% humidity. It makes it sooooo much hotter. I've been to Texas a couple of times, and though the temperature SAYS it's 110 in Texas and 95 in Florida, I gaurantee you that it's hotter in Florida.

 It just cooled off here and then went back into the 80's, but the humidity was low because it had just been cold out. It didn't feel the "normal" 85 to me at all.

 I was tempted to try this, but I don't know how well it would work. Worth a shot though I guess. Anything to make it cooler! Haha. ^__^
I hate weat, it just makes you feel hotter, sticky, and as if you haven't showered in 3 days.
i have a fan from a ps2 the fats but im not sure what is its voltage can u help me out SOMEONE PLZZZ
run it at 5v or less. i suggest using a POT switch (a turning switch) to save battery/use max performance.
any voltage beneath 3v and slowly move your way up stop when it doesn't get any faster
ANDY! (author) 5 years ago
it was cloth for wiping cars. It said it held a lot of water.
my friend made one of these once, and it began to work, but then it failed :( I guess all the evaporated water began to build up the humidity in there. Hmm, he should have opened the windows!
deryan975 years ago
that looks like a shamwow (kaboom shamwow)
Zem5 years ago
 Just using hot glue I would assume?
ANDY! (author)  Zem5 years ago
yeah, unless your place is super hot and it melts the glue. (just joking)
hot glue works fine
Zem ANDY!5 years ago
 Awesome, thanks.
jarjar7616 years ago
ok alot of ppls are saying that the hot glue doesnt stick well and i agree without even trying it past expirence failed anywho just use superglue it works for real
ANDY! (author)  jarjar7615 years ago
Maybe, but perhaps Im good with hot glue. ;)
  E6000 works great too. You can get it at your local hardware or craft store.
getack6 years ago
Attention to all those who don't understand the principle of evaporative cooling, or better known, swamp cooling... The secret in the cooling power lies in the effective evaporation of water (or any other liquid). We all know water exists in three phases: solid, liquid, gas (ice, water, steam). If we want water to move from ice, to liquid, to steam, we need to introduce energy into the system (the water). This energy comes from (in this case), Heat! A simple experiment is to turn on the kettle: the element heats up, supplying energy to the water in the form of heat, making it evaporate. This phase change is an endothermic reaction, meaning energy is drawn from the environment (the kettle) and the system (water) is then left in a higher energy state (steam). Please note the higher energy state DOES NOT mean physically hotter. A gas has a higher potential energy as liquid, and liquid has a higher potential energy than a solid, even if their temperatures are the same. Another good example of this happening is an aerosol can. No matter how much you preheat your deodorant (DON'T DO THAT!!!), the gas coming from the nozzle will always be ice cold, and the can itself cools down as the liquid inside evaporates. Now... After that, on to the swamp cooler :-) As the air is drawn over the moist cloth by the fan, the water extracts (absorbs) the energy (heat) from the air, making the air cooler than it was before. The water, after receiving the energy, evaporates, turning into a gas (water vapour). This vapour does NOT have the same temperature of the hot air. It is also cooler. Because it is now a gas. The heat energy was converted to kinetic energy to make the water molecules fly out of the liquid, to become a gas. Now, knowing that, you will understand the limiting factors of swamp cooling: Relative humidity, and temperature. The hotter, and dryer the air, the better and more effective will the swamp cooler work. If you have very hot air, but very humid, the swamp cooler will work poorly, might even make things worse. On the other hand, if you have very dry, but cold air, the water will not evaporate, and not cool the air. So where you live, really determines the effectiveness of your swamp cooler... If you live in South Africa, you can have several options. By living north, like in Upington or Musina, your swamp cooler will work very well. But if you live in Durban, down south, you will be better off falling in the sea. You want desert dry hot air so that it can work well. Tropical climate is a no go. I really hope I helped? If I am incorrect with any of my statements, please help me by correcting, although I believe I'm pretty right. Have a nice day!
enemigo getack5 years ago
In theory you are correct, however, I lived for many years in south Georgia and northern Florida.  Swamp coolers were used there by the majority.  I don´t think there is any doubt that it is very humid and hot there, sometimes in the high 90´s( F) and low 100´s in the summer with humidity to make the heat index sometimes feel like 115 or more and the swamp coolers worked very well.  The humidity raises slightly, true, but the actual temperature feels a great deal  cooler.  In any event when it´s hot outside a swamp cooler beats a fan unless it´s a very large volume fan, say 25-30 mph output.
enemigo enemigo5 years ago
a low cost/low voltage, bubble up fish tank airiator could be affixed to percolate water on  continual basis by simply drilling small holes along a 1/2" pvc attached across the top of the cloth or filter material (available at home improvement stores made specifically for evaporitve coolers).  12 volt fans can also be scavenged from the heater/AC from an auto in a junk yard.  If you go this 12 volt route an electric fuel pump could feed the airiator
 ii understod90%  of it, thx for making me a bit smarter :)
mhippo6 years ago
If you build it with a water reservoir and have the cloth dipped in there it can work for longer.
That's what I was thinking, too. Make a wick out of the cloth, then all you need to do is keep the reservoir filled.
ANDY! (author)  mhippo6 years ago
madd0g6 years ago
hi guys.. im from india.. in delhi(in central india) it IS VERY VERY DRY.. i mean humidity is so low.. and every house has a watercooler.. a watercooler is every thing u said here multiplied by 100... like the size and the amount of cool air u get is amazing... but in places where it is humid this thing is useless (i live in chennai.. on the coast..pretty humid..)so im guessing even this model would be useless...
ANDY! (author)  madd0g6 years ago
ha ha. I just read about solar drying food.
jakkels6 years ago
wow Andy these guys live in sealed houses without windows no wonder they can't cool their rooms. I live in South Africa and had a commercial version of a COOLER WHICH WORKED IN A SIMILAR WAY. they used a coir mat suspended vertically in front of a strong fan. there was a drip tank on top of the coir mat which maintained the dampness. You will be pleased to know that simple evaporation does work to cool homes here, provided you have windows or doors that open. Scientists often get caught up in technical details which is why entrepreneurs sell usable products. It's better to use it directionally - aim it at your victim. Nice one Andy.
jeffmeade6 years ago
what way does the fan blow? into the cloth or out the top?
ANDY! (author)  jeffmeade6 years ago
perferably into the cloth. i don't it matters much ]
tiabnogard6 years ago
Ingenious. I've been looking for something like this, and you sir, are a genius. I have TONS of these fans around here.
ANDY! (author)  tiabnogard6 years ago
yay. im still a minor too. not everyday where someone says that.
anth1016 years ago
Can you build me one and send it to me for my B-day............ Its August 27 HAHA
ANDY! (author)  anth1016 years ago
sorry. i dont want to pay for shipping ; )
Really, better make that 2 then, August 27 is my birthday too. However it's still winter in South Africa so I can wait a while :P
I dont get it
I was serious!!!!!!!!! jk( just kidding)
dciocoiu6 years ago
P.S my spell check dos not work so if i made any spelling mistakes don't be shay to tell me any one.
dciocoiu6 years ago
I like youre green idea for an Swampcooler infact i liked it so much that i downloded or more technicaly saved the PDF fille on my computer . It is a great Idea.
dp69_20016 years ago
In Utah it is Really dry and hot. Swamp coolers are extremely common here. There is one room in my house that I need to keep below 70f all day and I may consider parts of your idea for developing a way to do this.
ANDY! (author)  dp69_20016 years ago
Look up thermocouples on google made from copper and iron. YOu can make a parobolic heater outside and put them in the center for powering up a fan inside. You could spray a umbrellla (probibaly uncommon) with chrome silver paint to make one.
Hichi6 years ago
Ok Guys i have done the math. I used European units for the science part because i live in Germany. If you evaporate (thats what that thing is doing) 1 liter (0,26 gal(US)) and your room has a volume of 30 m³ (2,45m*4,5m*2,8m) then the temperature is reduced by 0,015°C (0,027°F). Since this thing is so small i guess it can only evaporate abut 20g of water/h it is comletely useless. So i cannot understand why it is featured. Sorry guy its much more usefull to just get some cold water from the pipe and plant a bucket full of it in your room.
Hichi Hichi6 years ago
OK i found out something else: at 25°C you can only evaporate 0,75liters of water into 30m³ of air otherwise it will start to condensate and give back the energy used to evaporate. SO that thing is not just completely useless its absolutely completely useless. hum i realy thought thats a good idea... well i still did not calculate what will happen if you put 10liter of 10°C cool water in a room of 25°C and wait until you reach the mixing temperature but i guess it is something of 24,8-9°C.
ANDY! (author)  Hichi6 years ago
When it condenses, it turns into kinetic energy
Hichi ANDY!6 years ago
Well ok the energy stored in the air surrounding the water is used to heat up the Water and The temperature of an ideal monatomic gas is a measure related to the average kinetic energy of its atoms as they move. But these atoms are not just heated they experience a phase change to acomplish that you need to put 2.442.000 (2,5MJ) Joules on 1 Liter of water at 25°C room temperature. This Energy is transfered from the surrounding air by reducing its temperature. (you need to extract 1005 Joule from 1Kg Air to reduce its temperature by 1k (1°C).
ANDY! (author)  Hichi6 years ago
How do you know everything. R U a scientist and tried it out? Geez people just post stuff that they think without every trying it.
Hichi ANDY!6 years ago
well iam running a bucket with 2 liter water in it, a vetilator on top and a towel touching the water surface and beeing tensed over the vetilator. This is running since 5 h and so far my room temperature has been risen by 1 °C (24,6-25,6°C) and the humidity from 30% to 35%. Directly in front of the airstream i got a Humidity level of 78% and a temperature of 19,5°C so it is in fact cooling the air (how it is suposed to) but when its mixing with the surounding air its not cooling overall. Oh and btw this is just simple science go to wikipedia and calculate it for your self.
robo_bob6 years ago
solar panels are like 20 dallors
ANDY! (author)  robo_bob6 years ago
I got mine in Canada for 7 bucks or you can use batteries or a rechargable flashlight thats hacked
robo_bob ANDY!6 years ago
ya thats true but all the solar panels that ive seen were pretty expinseve
fwjs28 robo_bob6 years ago
dismantly a solar powered calculator...
ANDY! (author)  robo_bob6 years ago
Make thermocouples.
this is cool, but it will not make your house any colder than just leaving a glass of cold tap water sitting out. However, this does use the same principle as Swamp coolers, which are used commonly in very hot dry climates, like arizona. It has to have a vent to the outside to exchange the heat. You could also improve it by adding a tupperware water resivoir underneath, to keep the rags wet. good job though
MechEngineerMike you are incorrect. The heat is dissipated via the phase-change from liquid to gas. There is no need for an outside vent. Furthermore, this is better than a glass of water because this set-up is much more conducive to evaporation. Have you given this any thought at all? Doesn't seem like it...
yes, the heat is Transferred, not dissipated, from the air to the water/water-vapor from the phase change. This contraption does help the water evaporate much more quickly than a glass of water, BUT this machine will not make the room any cooler than a glass of water ( after time has passed and there is no temperature difference between the water and the surroundings) .
If you put this machine inside a box shaped Superinsulater and also put a glass of water with an equal amount of water as the machine, under an identical box shaped Superinsulater, then after the temparatures have reached equilibrium, they will be the same in both boxes ( if the machine's fan created no heat).
So as long as this machine is not hooked up to the outside and inside of your house, it will not cool off your house any more than, say, filling your bathtub with cold water and letting it warm up.
Jeez, havnt you given this any thought at all? Doesnt seem like it....
btw nice hairdo, lol
You are still missing the point here. The heat(energy) that is transferred is used to change the water from liquid to gas phase. All this heat energy transferred for the phase change does NOT raise the temperature of the water.
ok the way i see it, there are 2 relevant equations, q=mc(T) and q=mL. For the phase change q=mL is used to calculate the heat transfered to the vapor. Yes, this heat comes from the air to the vapor, but the vapor is still in the room so it will transfer its heat right back into the room and just condense back into water somewhere else. I am convinced that if you filled a really wide tray (with lots of surface area) with water, it will have the exact same effect as this device.

btw, to ANDY! i am not trying to demean your device's value here, just talk junk to these guys.

On a side note, i am working on 2 designs for a cheap A/C unit.
One has a bucket underground and a pump to send water from the bucket through a coil where a fan can transfer heat into the coil and transfer it out of the house. Any ideas of how to make a (too) small water pump, pump water about 6 ft off the ground? a second water tank or a siphon or something>?
The other would work like a regular a/c unit with a small pump compressing engine coolant and expanding it at the right time. Do you think this miniaturized/cheapenized version would work?
You are right that the heat transfered to the water would be transfered right back into the room IF the water vapor were to condense. However, where would the water vapor be condensing, Mike, besides your beer cans? If a wall or floor is cool enough relative to the air to be condensing water vapor then your house is already being cooled somehow.
Hi Chrysus, When the amount of water in the air gets above the saturation point for the room temperature, it will start condensing out on surfaces even if they are room temperature. Another way to put it is that as the water that's evaporated fills the air, the dew point of the air in the room goes up. When it reaches room temperature you will have condensation.
Which is why evaporative coolers are only used in dry climates, typically less than 30% humidity. I assumed we weren't talking about a swamp cooler in Georgia.
There are indirect evaporative coolers too, that would work better for humid climates. The moist air goes into a heat exchanger and gets heated by room air. Less efficient, but more comfortable. :-) By the way, according to Wikipedia, the term "swamp cooler" comes from the algae smell that early designs had, not from being used in swampy areas.
One more thing. Your tray of water WOULD cool the air, however it would be much too slow to make a difference. That's the purpose of the towel/fan - to speed up evaporation.
If you let the whole galaxy just sit for an infinite amount of time, every single inch of it would be the same temperature. This says absolutely nothing about the various processes going on inside the universe. Obviously things would EVENTUALLY even out but if the long term impact on your super-insulated, super-sealed house was the important part, a lower-calorie diet would work better than all of these things. Who cares!
ANDY! (author)  MechEngineerMike6 years ago
Idon't think so. Try it yourself.
ANDY! (author)  MechEngineerMike6 years ago
Well you could make a big one.
ANDY! (author) 6 years ago
ANDY! (author) 6 years ago
ANDY! (author) 6 years ago
You guys are really technical. I used it and it works real well. Can you vote for me too?
Lol, maybe step it up a notch... Use a huge cattle fan and 2x4's with like twelve soaked towels... haha no, this is a cool idea. It has to be efficient, especially if its powered from solar panels. I may have to try this...
ANDY! (author) 6 years ago
dombeef ANDY!6 years ago
lemonie6 years ago
You should stand this in a dish of water for a wicking-effect, lovely simple design and nicely presented. L
jeff-o lemonie6 years ago
Then it would be a humidifier - we have two in our house. Great for the winter when the house is bone dry, not so nice in the summer when it's already 80% humidity!
ANDY! (author)  jeff-o6 years ago
IN Canada, it's hot and dry. I con't know anything about your place.
ANDY! (author)  jeff-o6 years ago
I mean condenser
Odyssey jeff-o6 years ago
It's humidifying either way--it's just that one way, you're adding the water in smaller amounts. This is really just a small version of a swamp-cooler, a device that's ubiquitous in the deserts of the western US. They're quite effective when the air is very dry, but much less when the air is humid.
jeff-o Odyssey6 years ago
Ah, but a swamp cooler is slightly different. A swap cooler circulates cold water through a coil, but the water itself never evaporates. A swamp cooler will actually cause water to condense on the coil, drawing moisture out of the air.
Swamp coolers are evaporative coolers, like this. I think you may have some of your terminology confused.
I think I was thinking of an indirect cooler. Whoops! I Wiki'd swamp coolers and this would indeed cool the air in a small area. Apparently, it works best where the climate is warm and dry.
ANDY! (author)  jeff-o6 years ago
Make a consenser.
geekazoid6 years ago
That's a great idea.. keep it up! pıozɐʞǝǝƃ
Just dont use a sham wow....
SHAM WOW!!!!!!!!!!!!!!!!!!!!!!
ANDY! (author)  aarondelacruz6 years ago
nice, ill make one and tell you how it works out.
PKM6 years ago
I had a heat pipe salvaged from my shuttle that I did something similar with- left the heat exchanger block (originally the CPU heatsink) in a mug of ice water and put a fan on the radiator, so there was a blast of cold air as long as I kept the ice topped up. In winter you can use boiling water and warm your hands up :) You could use this for simething similar, using the evaporation to cool the heat exchanger and the radiator, then blowing air over the radiator to cool that. The only problem is I think the heat pipe doesn't like being submerged and started leaking a weird crystally substance. Anyone more clueful know of a way to avoid this? Or was my heat pipe just broken?
john karma6 years ago
yes you are cooling the water on the cloth, and increasing the relative humidity of the air (if its not already saturated) . The enthalpy change is not effectively used to cool the air however. Some thermodynamics tells us that you are not changing the total energy in the closed system. To cool you need to remove the "wetted" air and use the cool cloth to cool air.

It can be done by : blowing the air from the fan to outside your house. and using a radiator/heat exchanger which is cooled by the cloth and where air is run through and passed back to the room.

however such as small unit would be nearly useless.

Keeping the sun out, and hanging a wet towel with a fan directed at it in front of an open window at night is far more effective.

to learn how much heat you could remove learn to read a Mollier diagram which is used by engineers to estimate cooling tower performance

Boss_Sauce6 years ago
Sorry but I this is neither air conditioning nor efficient.
Yeah it is a simple air con. We have one with the same principal to this to cool our whole house (ducting going to every room) And it is efficient because the much larger version for houses (like we've got) use far far less electricity than the refrigerant A/Cs.
ANDY! (author)  Boss_Sauce6 years ago
Well i think it's cool anyway
vikolord6 years ago
hell yeah, very nicee, thnx for that trick hehe
Jupitane6 years ago
Im going to build one, ill tell you if it works or not ;>)
ANDY! (author)  Jupitane6 years ago
good luck
kelseymh6 years ago
Very nice build of a miniature swamp cooler, and well documented!
XOIIO6 years ago
cool idea, if you wanted to make an extreme version, you could modify my desktop fan, for a bigger effect.