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No-electricity air conditioner.

If electricity is scarce.
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Air conditioning is very nice in hot climates. However, most air conditioners are electricity hogs. In places where electricity is not reliable (for example, Iraq), people may not be able to run air conditioners. The same is true for rural parts of much of the world.

An air conditioner is a compressor and a fan. This could be run using strictly mechanical energy. I propose ammonia- using air conditioners driven by a wheel on the side. The airconditioner wheel could be attached by a chain to a bicycle, or a windmill, or a large wheel pulled in circles by an animal. Anhydrous ammonia is a fertilizer and should be more widely available than other refrigerants.

The resulting coolness would be cool. I read in wikipedia that small airconditioners use about 1800 watts. A person on a bike could generate 250 to 500 watts. The no-electricity AC would take longer but still get the job done.

I wonder if currently used ACs could be retrofitted to allow no-electricity use?

One problem is night use in the tropics. Iraq is windy, but in Ivory Coast there may not be much wind. Ideally, air conditioning would allow the building to be closed up - conserving coolth, and preventing ingress of mosquitoes. Someone will have to stay up all night and pedal or drive the animal.

bungston, Sep 02 2007

Refrigerator schematic. http://home.howstuf...m/refrigerator4.htm
[bungston, Sep 02 2007]

PVC air conditioner http://mb-soft.com/solar/saving.html
long read - but worth it. [TIB, Sep 03 2007]

Ammonia absorption cycle http://www.howstuff...org/absorption.html
[Ned_Ludd, Sep 04 2007]

Anhydrous ammonia down on the farm http://www.extensio...systems/DC2326.html
[bungston, Sep 06 2007]


       Have you seen the film (or read the book) "Mosquito Coast"?
Srimech, Sep 02 2007

       how about this?: two stirling engines (simple, pressurized with air). a thermal solar panel collects heat - basically black pipes enclosed in glass - that runs stirling #1. mechanical output from this runs stirling #2. stirling #2 is used as a heat pump to cool a room. to increase efficiency stirling #2 hot side could heat thermal-solar fluid before it hits the panel.   

       the neat part is that it would automatically start running as the day got warmer - all mechanical, no refrigerant required.
TIB, Sep 02 2007

       A trained cyclist might produce 250-500W. Your average human might be able to crank out 150W for a few minutes before getting bored with it.   

       Solar absorption cooling would likely be a better option, if A/C was valued so highly.
Texticle, Sep 02 2007

       even easier would be to dig some trenches and lay pipe - run air though this pipe and into your room. use the earth as a heat-dump.
TIB, Sep 02 2007


       //Your average human might be able to crank out 150W for a few minutes before getting bored with it.//   

       Or before getting too hot to continue ...
nuclear hobo, Sep 03 2007

       There are butane (direct heat) powered refrigeration cycles that could also be adapted to run under solar power.
Ling, Sep 03 2007

       Anhydrous ammonia is not a fertilizer, it is a pretty nasty gas. The fertilizer is Ammonium Nitrate. However, I think you are on the right track. Don't worry about the nights. You can store water and ammonia separately to mix them at night for cooling. No need for anybody to stay up, if you work hard enough throughout the day to separate ammonia from water. During the day a solar panel could help you to boil the ammonia off the water.
kbecker, Sep 03 2007

       Or you could just buy a generator.
Livingfishguy, Sep 03 2007

       Ostriches are a possible solution - and I cite the following -"can be drawn along by a team of ostriches (given that each ostrich produces around eight to ten kw of useable energy a team of fifty ought to yield 750 kw-1000 hp) -excess power could be drawn off via a generator linked to the wheels thereby negating the need for an outside fuel/power source, as the ostriches can browse on twigs, berries and grubs as they run. And god knows they love to run!"
the dog's breakfast, Sep 03 2007

       the modern version of the palm leaf - waving slave. Lovely. The additional heat by the cyclist would be quite a load on the ac, so he better stays outside.
loonquawl, Sep 03 2007

       // each ostrich produces around eight to ten kw of useable energy //   

       [the dog's breakfast] 9kw = 12hp so I doubt the strength of your ostriches.
marklar, Sep 03 2007

       [TIB], [Ling], and [kbecker] do seem to be on the right track. How about solar-heated thermal mass as a heat source for an ammonia-absorption-cycle air-conditioner? That way there is heat available to drive the process during the hot early part of the night.   

       The advantage of such passive systems is that one need not aim for an extremely high efficiency, as the energy source is 'there'. It changes one's whole outlook on efficiency to a much saner one, i.e. with a focus on practical feasibility rather than extracting every last bit of hypothetical energy.
Ned_Ludd, Sep 04 2007

       I considered 24-hour solar power generation once. The calculated size of the heat sink was rather too big to be practical. For cooling purposes you could cool the heat sink during the day but i think you would still need a rather large chunk of steel (or whatever).
marklar, Sep 04 2007

       Ya, that would work but this is a already burnt idea. Remember we replaced windmills, water wheels, cows, and slaves with motors...
F_R_O_G, Sep 04 2007

       We've pretty much replaced the motors with slaves again, only we don't see them unless we live in south-east Asia. If we're wise we'll replace both the slaves and the less-inspiring majority of motors with windmills and water-wheels again.   

       [marklar], the question is, how much power do you aim to generate? Are you looking at a conventional suburban 9000+ kWh/year or rather something like 1500-2000? Everything about the former would be too big to be practical. Various solar/wind/water combinations will work in the latter case. My point was that the greatest (domestic) energy demand occurs some hours after the greatest intensity of solar energy, and that thermal mass can be used to good effect with a non-electric system such as the one under consideration here.
Ned_Ludd, Sep 06 2007

       TREE HUGGERS!!   

       jk, but why not use what we has available right now? they are eventually going to have electricity for most of the day. also remember that it would have to be cheap enough for them to buy it for it to work.   

       Now let me finish my beer...
F_R_O_G, Sep 06 2007

       [kbecker], I am always happy to distribute some larning. Linked please find instructions on how to use anydrous ammonia on your farm. Once you are aware of this use, you might spot tanker trucks of the stuff rumbling about. I am not certain it is as widely used in the 3d world, but I just do not know. I understand that anydrous ammonia is also used in the production of methamphetamine, and occasionally meth chefs get messed up while stealing anhydrous in the dead of night.   

       I must say I am tickled to have this idea annoed by the good Mr Ludd. This concept seems squarely in the [Ned Ludd] strike zone.
bungston, Sep 06 2007

       If you build houses the right way they don't need to be air conditioned.   

       Building shoddy housing to save money and then spending a fortune on air conditioning is the wrong way to do it.
kinemojo, Sep 06 2007

       It gets about 100 F with about 95% humidity here in the summer. How should my house be livable without air conditioning?
nomocrow, Feb 24 2010

       / How should my house be livable without air conditioning?/   

       I like the use of the word "should", which casts what would otherwise be a banal rhetorical question in a different light.
bungston, Feb 24 2010

       why not use air within the room itself instead of ammonia ? Compress the air, blow the fan over it, release/evaporate air into the room.
VJW, Jun 08 2011

       / How should my house be livable without air conditioning?/   

       A house built from, or with, materials with a substantial thermal capacity will do the job without the need for air conditioning.   

       My house is built from brick, flint and clay lump, with walls 2' thick. It stays cool during the hottest summer days and remains at a comfortable temperature even if it gets cold outside during the night.   

       It's not the most effecient place to heat during the winter, but if an external insulating layer were added, that could be improved.   

       The point is, all that is needed is a thermal mass. If that mass is the house itself, nothing else is needed. Otherwise, it could be as simple as a large underground water tank and some heat exchangers (radiators) around the house.
Twizz, Jun 08 2011

       //even easier would be to dig some trenches and lay pipe - run air though this pipe and into your room. use the earth as a heat-dump//   

       //If you build houses the right way they don't need to be air conditioned.//   

       Both of the above are on the right track, but there are places like Florida where the humidity alone make AC a requirement at least for me where I'd say, start with thick walls (Earthbag is cheap), add large overhangs or better a thick green roof and then add a little ground-loop AC to drop the humidity and then even the Sahara and the rain forest should be livable, with the added bonus that you can also ignore tornado warnings, though you have to worry more about flooding.   

       The only advantage for this idea is in the first world as most of us could use some more exercise. (-)
MisterQED, Jun 08 2011


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