Instructables

Stay Cool Without A/C.

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Recently I listened to a podcast from an Air Conditioning expert, which I didn't even know existed . It got my brain going about how to stay cool without using an air conditioner.

I have been trying some of his tips, plus some of my own ideas, and thought I'd share them here.

The results have been very successful, and at my house we now run our air conditioner for only brief periods of time throughout the day while the other tenants in our unit blast theirs almost nonstop.

The most interesting thing I discovered is just how arbitrary the standard 72 degrees F is. I am convinced that this temperature is based on wearing a business suit, which people almost never wear in their own homes in the summer. The truth is that there is no ideal temperature.

These ways to stay cool fit into three categories: Lowering the temperature of your house, lowering your body temperature, and changing your perception so that the heat doesn't bother you so much. Not all of these steps are practical for everyone, but if you can find one or two that you can turn into habit, it can make a difference in comfort and/or in energy consumption.

In addition, I have listed some bonus "green" benefits on each step where they apply.
 
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without quotes from universities on my side , i bed to differ on some points . I think it matters if the body is active or not. I've seen hundreds of times where active persons in a freezer have huge wisps of steam billowing off their heads . If they put a beanie on this wisp is slowed or stopped . Its one of the fastest ways we cool down ,just by removing the beanie . You see it in sports often , http://www.blogcdn.com/www.aolnews.com/media//2007/11/steam-head.jpg
Now ,seeing workers in the freezer with nothing but a wifebeater on their upper body shows that its not the clothing holding in the heat ,only allowing it to escape from only the head . Even with only a tank top ,the majority of steam comes from the head .

My guess: There are lots of veins close to the skin on the scalp that act like radiators when overheated . No scientist to back it up ,just a decade of field testing =)
Of course it looks like steam is billowing from their heads. Not only is it often the largest area of exposed skin, steam rises, so the steam coming from the rest of the body appears to emanate from the head.
The fact of the matter is, it IS a myth that we lose the majority of heat through the head. The body is basically a radiator, as blood flows through the skin. As such, the heat that is in the head is NOT in the head a split second later, it has been pumped out. As with all radiant heat systems, there is no localized area of major heat loss.
Certainly your example of the man in the freezer is spurious. First, it does not even address the key issue. Second, as addressed above, it is not really accurate, and is mostly an illusion. Third, the idea that clothing does not hold in heat does not survive even superficial scrutiny, and fourth, it just simply is not true.
Get an infrared camera and take pictures. The relative intensities of heat will bear out the science. Unless your head is 50% brighter than the rest of your body...
Not sure why you posted this in reply to me, as I am agreeing with you! :)
tinaam Phil B2 years ago

I've heard the thing about wearing hats in the winter...so why do we wear sun hats in the summer?  Seems that would make us hotter?

gtoal Phil B2 years ago
Yes, but we also took advantage of the Indian invention of the punkah-wallah - possibly the least efficient form of AC in the world!
So much for evaporative-cooling systems in a tropical climate where everything is humid. Well, sleeveless shirts also work in conjunction with shorts. It's pretty much the only way I could work in the house for some reason...

Oh yeah, back to basics, keep a handkerchief or anything of that manner with you in case you sweat like hell. That's what you do when you're in an epically humid environment, where sweat doesn't evaporate nearly as fast if you were in the drier climates.
jillf2 years ago
You have overlooked the most effective way to stay cool--stay wet! Wet clothing will keep you much cooler than going naked. Unlike skin, which dries fast, clothing stays wet. No need to waste water or sacrifice your modesty--you can wear wet clothing indoors, outdoors, and in front of anyone. Wet clothing will also protect you from sunburn when outside in the sun.
I like your TV stand...
Bindlestiff (author)  herquiltness2 years ago
Haha. The TV is a temporary fixture for us, and we usually like it put away out of sight when its not in use.

I am very amused that you noticed!
Well, I like that you made this ible -- it's good common sense, and while I adore techie things, we don't need a techie solution to every problem posed. As for my noticing-the-TV-stand-smart-remark ;-)... ibles authors should be given the opportunity to enjoy non-political observations, too. That you were amused indicates we may share the same kind of humor and ible-think!

Have a sensational day, Bindle!
JD_Mortal2 years ago
White paint DOES NOT REFLECT HEAT. That is an old wives-tale, and completely inaccurate. You need thermal exterior paint, which is any color. Visible light does not absorb heat or reflect heat. Colors we see are NOT in the thermal range. Reflecting all of the colors we see is useless.

IR (Infra red) and FIR (Far Infra red) are the two heat sources, which we CAN NOT SEE. Thermal outside paint reflects that spectrum. With a thermal camera, that paint looks bright, but it is not white. The colors range to any color, and even include the darkest shade of black.

Remember, if it reflects heat... that only keeps outside heat out, but it also keeps inside heat in... If it is hot inside, thermal paint makes your house feel hotter, not cooler, unless you have AC to remove the internal heat. Your body is a 98.6F open flame running around your house, heating it to above the 90F that is is outside. You will feel that heat more, when your house has more insulation.
I have no complaints about your argument. I'm not sure how it fits with clothing. Could you explain how lighter colored clothing is better at keeping you cooler than dark-colored clothing?
That is not true...

White cotton = hot.
Black silk = cold.

Color is irrelevant. If it is cooler, it is a coincidence that the material is IR reflective, and if hotter it is IR absorbent.

This is easy to see with an IR camera.

Coke is black, but in an IR camera it is as clear as water. Thus... it is cooler than milk, which is black in an IR camera.

On a majority, light colors MAY (on average) be cooler... But saying ALL is a wives-tale. If you paint your house with the wrong "white", that is "black" to an IR camera, you just made someones problems worse.

To see the true IR-reflective or IR-absorption of any paint, any color... paint a cooler and poke an oven thermometer through the side (in the shade side). To compare with something that is IR-reflective, use a thermal-blanket (Mylar) from a camp-supply store. Wrap the second cooler with the thermal blanket and place another thermometer in that cooler.

Any paint, except thermal paint, (which contains aluminum and ceramic), will be hotter than the thermal blanket cooler. Black will usually be equally as hot as white. Technically, bright RED would have the best IR reflection potential, since white is all colors, but unless the white is a mirror-reflection, it is absorbing more than it is reflecting. Unlike the bright red, which is reflecting nearly all the red light spectrum, into the infra-red layer. But it will only be 1-2 deg cooler, at the most... insignificant when it is 100F.

Reflecting is not good... it reflects the 100F sun away, and reflects your 98.6F back at you... That is why you will overheat if you use that thermal blanket in the summer... Thus, again... reflecting heat is NOT good. You want to remove the heat away from your body fast. (That is partly why silk is cooler, it breaths and is thin. Cotton is thick and is heat insulation.)
as an architect I can tell you that color DEFINENTLY effects temperature. Your comments are valid but when you talk about color you need to take the material out of the equation.
white cotton = hot
black silk = cool

if you take the material out of the equation and compare apples to apples, color does effect temperature.
white cotton t shirt = cool
black cotton t shirt = hot.

your comments are not about color. it's that simply different materials absort/reflect heat differently. no question that's true.

as an architect I can say that exterior paint color does not effect the interior temperature. dark paints do absorb more that light paints but that is limited to the outside skin of the house and doesn't work into the interior. where it really does make a difference is roof where you have the most solar exposure. it's been very well studied and documented that light color roofs are cooler than dark color roofs. with a house that has an attic the insulation layer is normally in the ceiling and not in the roof rafters. a black shingle roof will absorb more heat which will effect attic temperature more than a white shingle roof. (which is why attic ventilation is so important)
I deal a lot with flat rubber roofs on commercial building. if you've been on a black rubber roof on a hot summer day there is no question that it's hot. this is the same as standing in the middle of a black asphalt parking lot. if you compare temperature of a black rubber roof versus a white rubber roof there is a substantial difference. because commercial buildings often have there cooling equipment on the roofs changing the temperature of the air around the cooling tower, with a white roof, improves the cooling efficiency of the hvac and can dramatically lower utility bills. this has been very well sudied and prooven. it's called the HEAT ISLAND EFFECT.
It is a well-known fact that heat is reflected by lighter colours more than darker colours. An easy way to prove this is to establish first that sunlight = heat via infrared radiation. This can be tested by keeping a thermometer in shade, and a second in direct sunlight. Once this has been established, take three identical pans/bottles of water, painting one white and another black, then one grey as a control. Place these in sunlight for one hour, then test the temperatures. The lighter the bottle colour, the cooler the water will be.

Therefore, we can take this proof into the real world by painting a house or even a room white, which reflects more light than darker colours like black or dark blue.

Finally, wearing clothing that ensures all heat is reflected away is an excellent idea, one which I have used countless times in my life as a Sydneysider :). (we get 40C+ summers here, sometimes more [thats 105 - 115 for you Americans] ).
All electromagnetic radiation turns into heat when absorbed by matter. That's why your microwave works. The visible spectrum is a small portion of the electromagnetic radiation out there, but, for the same kind of paint, lighter colours will reflect more than darker ones. A black thermal paint may be cooler than a white, non-thermal paint, but a white thermal paint will be cooler than a black thermal paint.

The tradeoff, of course, is that, once they warm up, reflective surfaces also re-emit less of the heat as electromagnetic radiation, so they take longer to cool off. So you're going to want some kind of conduction/convection cooling for your house at night to dump the waste heat. Also, don't paint the inside of your house with brighter colours, as that will reflect more of the internally generated heat back inside.
Hmm... I agree and I disagree... lol...

Microwaves are tuned RF radiation which excites only water H2O. (Though it will also heat-up and collect on metals as ions, exiting as sparks/static).

Visible light is cold. +/- 0.5 deg, and thus, irrelevant to comfort. IR is responsible for 95% of the heat on earth. (Microwave and other radiation is the remaining 5%)
Actually you can use your microwave for melting lead, aluminum, and maybe brass... ;) Most of them don't put out enough power for more than that.

Most digital cameras can see IR. Especially black and white ones. You can use one and a few IR LEDs to test the reflectivity of things pretty easily.
You can take apart a cheap webcam, remove the IR filter, and replace it with film-negative which is black after developing. That will block most visible light and let you see the IR reflection/absorption in daylight.

But that is only near-IR not far-IR, which is the real heat-wave. You need a FLIR thermal camera to see that "true" reflection/absorption.

There are a few youtube videos of a person who tested many materials, including paints, plastic and metals. All paints showed as black/grey (absorbing) in ambient air, but lit-up when heat was near it. While aluminum looked like a mirror reflection ambient or directly cast with heat. Plastic was pitch-black in ambient air, until a heat source was directed at it, then it lit-up like the aluminum but did not reflect. Paints are 98% plastic/latex with 2% or less pigment coloring. Black paint is no-longer carbon-based like it was in the old days. Carbon is highly IR absorbent, but toxic in paints. White paints were once aluminum-oxide, again a toxic paint additive which is no longer used. Most pigments are now plastic based which are high UV resistant and stay vibrant and less toxic when they break-down in the weather. Plastic in the paints, like water, absorbs IR more than it reflects. (No matter what color it is.)

The only exception with paints, is thermal paints which are 20% plastic/latex and 80% ceramic and aluminum. (It is a patented paint. Not a normal consumer paint that you would ever buy at a paint store.)
What exactly can be toxic about carbon or aluminum oxide? Carbon is in you and aluminum oxide is one of the most inert substances you can get. You can literelly eat both.
gia minifig9042 years ago
The Arabs wear black wool garbs in the desert. If black made them stay hot, they'd probably wear white.

So easy to test - whichever temperature is hot for your area, go out one day in white or light colored clothes, and the next day in similar clothes - material, thickness, how loose/fitting it is, how much it covers etc - but in black, and observe any differences in how it feels.

The reason Arabs prefer black is that it does not allow the moisture to keep evaporating. It remains on the clothes you are wearing, and that cools you down a bit. White instead makes the water evaporate, and if you are in a really hot and dry place, such as a desert, that makes a huge difference.

Actually, wearing the Arab style clothing (black, wool, loose-fitting) might be something to try around here in Central Texas. The temperatures have averaged around 104 F since June (40 C), and at night it's still over 80.
I believe you are saying that because white surfaces reflect visible light, they do not necessarily reflect invisible IR energy. White paints DO reflect visible and invisible electromagnetic energy (IR). Darker paints absorb this same energy, and release that energy much more easily than white when the surrounding temperature becomes cooler. Thermal paints, in any color, have insulating properties and serve to retard heat conduction from the surface into the solid it is painted on and have nothing to do with radiant absorption, except in their color differences. Luster also figures into this. As a practical test, take a barefoot walk on the street this afternoon to see if you might not prefer to walk on the lighter color surfaces rather than the black surfaces. Google "white paint reflects heat", and you will find many scientific answers on this subject.
crankyjew2 years ago
solid instructable, friend. this all works in steamy dorm rooms too!
stargeek872 years ago
Been living in Texas with 100plus degrees for almost sicty days straight. all these sound good but they dont quite help with those high temps
lbrewer422 years ago
Good, common sense suggestions. I agree with the evaluation of the 72 degrees being "optimal." I am a little different in that I thrive in weather at about 30 degrees (and humidity in this is a plus to me). I enjoy breathing in frigid air and my only guess as to why is that the air, being colder and therefore more dense, contains more O2 in it. I love to feel it filling my lungs.

One point I will not belabor past this posting though is your mention of emissions. The facts are that the people who thought up the politically correct farce of global warming were caught with their pants down and admitted it was a hoax in October 2010 (to which the media immediately started trying to hush all of this up - including Wikipedia entries). Do some honest research. If you are old enough to remember the ozone hole - which we were had crammed down our throats multiple times each day from every media source that there was during the last 15 years of the 1900's; you must ask yourself the question of, "where did it go - why are we not suffering the horrible ramifications of this hole's inevitable growing in size and cooking us all? Oops - global warming's most solid, undeniable, "scientific" PROOF closed itself up JUST when the horrible chlorofluorocarbons were supposed to wreak havoc on it in the year 2000! This should have been headline news - the only place I saw it was a small article at the bottom of the front page of US today. And the media let the concept slowly die.



Jesus christ, because we stopped using half the aerosol chemicals that were destroying the ozone layer. Plus, the hole presents itself first at the poles, where few people are really around to complain about it. Your kind of posts just tick me off, as it's far easier to sow doubt when people want to be lazy asses as yourself and avoid thinking about it on their own, rather than doing your own thinking, research, and evaluation.
An ad hominem response such as yours automatically invalidates your position - these are standard definitions and rules of debate. please look up the term so your posts will not automatically bring doubt as to your own credibility.

I have to wonder if you were even around (and sickened by) the torrential hammering of the "man-made ozone hole" scare/farce of the last century.

The hole closed at the very time we were told the "harmful gases" we had been using were going to finally reach the ozone layer and cause it to widen and scorch us. This was the scare tactic they used to get people to stop using the gases in the first place.

please do take your own advice and do your own homework on the subject. I have put extensive research into the farce since its inception. At first, in the late 80's, I took what they were telling us as an idea i wanted to research - i had no agenda. The media and politicians pushing it so much started hinting that pure science was not being adhered to and/or ignored. Observed scientific facts have revealed this farce over the years while media/politicians have been trying (and succeeding) to use it for financial gain.
I haven't done ANY research into the matter, so I'm probably perpetuating falicy, but I heard from a guy at the college I attend that the basis for a lot of the ceasing of use of the chlorofluorocarbons we were using was shrouded in the global warming/ozone story, but in reality, Dupont's patent on the refrigerants was about to run out, so they had to develop a new product, and a reason to get everyone to dump the old one.

I am however, all for stepping up efforts to reduce the depletion of natural resources and the poluting of the air as well as ground water supplies. I have COPD, and I breathe much more laboriously when the ozone level number is higher (and a lot of times I don't find out it's higher until the last news report of the night, and I have had more breathing issues all day). As for the global warming being a farce, or not being a farce, I don't know, but conservation is just responsible regardless.
Throughout history people and corporations in power have exploited the technique of using a tragedy for financial gain. I do not know if this is the case here - but, let's face it... we find ourselves living in a time very far from immune to utilizing this modus operandi.

There is just too much scandal/politics/money involved in all of this.
"The hole closed at the very time we were told"

The hole isn't gone. Who told you it was gone? It's just smaller, not "closed". You've just ruined your own (possible) credibility.
Early 2000 USA Today ran an article, complete with satellite photo that the hole was closed. The facts are that now true science ha shown it to be a naturally occurring phenomenon that fluctuates according to differing conditions that we do not fully understand and cannot predict accurately. However, b/c it disappeared when it did, it was something the media could not longer claim as proof of their farce - they did NOT predict it would disappear, but worsen with time.
Could you kindly explain how a "satellite photo" can prove or disprove the presence of colorless ozone?
I do not know the photography techniques use. However, this is technology that was used all the time to take pics o the ozone hole during the 80s and 90s - up until 2000. I am sure googling the subject of taking pics of the ozone layer will shed light on this. I would suspect it has something to do with using some sort of chemical analysis by differing wavelengths reflected from the ozone. I only guess tis b/c, since we know the ozone reflects certain types of radiation detrimental to us, it might be by the use of this very fact they can map the ozone concentrations. this is only a guess though.

I it turns out that they cannot take pics of it anyway - all the more for them pulling a hoax :^))

My point exactly... they are NOT photographs, as you claimed to have seen, but computer images based upon the data collected.... data that still shows the ozone hole as of June of THIS year... not 2000, nor 2004, nor 2006, we are talking 2011 and the real raw data does show that it varies depending on temperatures, air flow, and other atmospheric variables. Even so, the overall trend had been increasing over the previous decades and still is, although at a much slower rate than before.

The point is that it takes a LONG time for variations to affect the entire atmosphere. Perhaps you might have noticed that hurricanes and thunderstorms have been getting stronger and more violent over the past couple decades? Guess what? Those storms are powered by the great atmospheric heat pump... more heat = more power for these storms. This is not speculation, it is FACT that is supported by Dozens of widely different sources. It is not something that can be hidden... or "hoaxed".

You may consider it a hoax because you have not seen much effect so far, but we are talking something that could take decades to show serious effects and by then it would be far too late to do anything. The reason why the ozone layer and greenhouse gases argument has changed over the years is because there are more variables to take into account and their interaction has been difficult to figure out. If they were easy, we would already be able to forecast weather with perfect accuracy. Perhaps you have heard of the "butterfly effect" or the Lorenz Attractor in chaos theory? Check those out and you might understand a little better why things are being taken a bit slower now and why you think there is a "hoax" when it is actually trying to get more accurate data to accurately find out what is happening and be better able to predict future possibilities.

I have observed and studied those theories and global warming over the past few decades as well, and looked at BOTH sides of the story... neither are entirely correct nor are either entirely wrong. There IS something going on and the trends seem to point towards overall global warming in part due to our influence. There are several mitigating factors which weren't accounted for originally but are now being added.

As a side story, when the atomic bombs were first about to be tested, there were lots of scientists who were entirely certain that exploding those bombs would cause a chain reaction throughout the world and burn off all the atmosphere. Fortunately they were wrong, however, they were absolutely right about radiation sickness, mutations (to a lesser extant), and "nuclear winter" effects. Again neither were entirely correct nor were either entirely wrong... same as in this scenario. Perhaps we should take a care now and act on these warnings while we are still able.
Sorry for the semantics for sake of brevity. What i did see were printed images on paper.

Good point about the actual data not being what it was always claimed to be back in the late 1900's. The situation is much more complex than what the media was pushing as absolute fact. As you said, the ozone fluctuates depending on temps, air flow, and other atmosphereic variables. It is not what we were told back then as being a man-made phenomenon that was going to cook us all by the year 2000. The media always hyped it as this. And this was/is my point of contention as I have never seen the media, after inundating us with the ozone hole scare, take the time to reveal what they were so adamantly pushing was speculation. We only got reports on the media of how the temp of the earth would be 9 degrees warmer - on the average - by the year 2000 and that palm trees would be able to be grown in Erie, PA (which for the Erie-its would b a welcome change form their arctic-like Lake Effect Snow winters!).

Ozone depletion is an interesting study, however, since the inception by NASA (I think the early 80's?), there have been times, such as in 2000, when the hole (well -not really a hole - a thinner area of ozone) closed. Thus indicating it has not been a constant rise at all. I do not know if it has closed again, but continually fluctuates. The "hoax" was in the way the media has presented GW as absolute fact (especially man-made GW). There is much fact (after the exposure of non-objective science in the hockey stick graph debate) that shows
we are far from being a an "unprecedented" warming cycle. There is objective data pointing to the idea that there were much warmer periods of time in the earth's history ad this was before industrialization.

The "butterfly effect" definitely serves to substantiate the improbability/impossibility of making absolute/factual predictions as to temperature/weather conditions beyond a week's time. We can speculate, but once the speculation is taken as fact, and a goodly number of people have been repeatedly exposed to the idea being equated with fact, we have entered the realm of a farce.

I can agree with you that a fraction of a degree in warming trends may be present at this time. However, even the hockey stick (that Al Gore so loved to present and quote), if it was an objectively scientific representation, only displayed a rise in temperature of a fraction of 1 degree! This is a far cry from the overall picture that was so readily "reported" by the media. During the initial time period of this theories inception, there was no absolute proof on either side. Yet it "became" factual to the public in a very short time period. Initially, and for a very short time, the media newspaper (correctly) called GW a theory at first. However, this lasted a very short time. After all, gloom, doom, and exciting headlines sell papers.




please take this arguement to a political page, I'm looking for comments from readers pertaining to the instructable
Hey, to be clear, I disavow this post, I was pretty unnecessarily aggressive (for which I apologize), though I don't know why it was. My post that cast this shameful past away seems to be much farther down on the comment chain.
Please keep the name of Jesus out of this! It is offensive to some of us, and in all-around bad taste. Let's just talk about the instructable, shall we?
The ozone layer and its shrinkage has nothing to do with man-made global climate change (don't call it global warming) so any comparisons are spurious. But I'll bite, which climate scientist admitted it was a hoax?? Since I work in the field, I would be interested to know, having not heard of any scientist state this.
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