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thermoelectric(peltier) based AC system??

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settra

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Hello forum! this post is far irrelevant , to the topics of this forum, but i need the help of someone who ahs worked with thermoelectrics before... : )

i was thinking of an car ac system, that consists of the following:
1)3-4 peltiers, (they would drow 30A or something).
2)a water block, that on the inside it looks like this :
, but maybe with more dense structure.., mounted inside the engine bay.

3)the peltiers will be mounted on a way, that the cool side, is atached to this block, and the hot side, is cooled by cpu coolers or normal fans.
4)use a water pump, to push water through this water block, and then , push the same water , throu the stock radiator inside the car cabin.
5) then blow air throu that radiator, and hopefully be cooled.

can somone with experiance on thermoelectrics help me ? :) will around 300watt , be enough to make a diference on the car cabin??
any info would be appriciated :) thanks!
 
300 Watts is not enough. Even the human body generates about 100 W of heat. So, a car full of 3 to 5 people is enough to kill the effectiveness. Then, consider the sun beating on your car and the greenhouse effect. Larger TEC systems that might do the job may not be cost competitive, nor size competitive with standard AC of the car.

Still, for personal use, with the windows down and if you just want a little bit of cooler air blowing on you, it might work. Also, it looks like a fun project, if that is one of your goals.
 
Also remember these things have low efficiency, a 300W system would only remove 100W of heat.

as a rule of thumb most car ac systems take 1 or 2 hp from the engine and that equates to 750 - 1500W, and these are much more efficient than peltiers
 
Also beware to either have the system well sealed or use a biocide to keep bacteria growth down.
 
i am trying to install AC system on the car, and i find it very dificult :/ i would preferred to even install a second alternator and run a 1500watt peltier system, than having to deal with the compressors and the V belts... :(

but if you say that the effieciency will be this low, and especially where i leave (too much sun), then i suppose its of no use... :/
 
I think your idea would be able to blow some cooler air on you, the driver, but couldn't be expected to lower the inside temp much.
 
1500w is 2 hp, you would need a seperate splined belt or multi v belt to transmit so much energy.
 
Bottom line. It isn't worth it. Peltiers and Vortex coolers work for some electronics enclosures.

I've done a car install in a 1982 vehicle from a box. It was about 13 hours of work by myself not including evacuating and charging.

The instructions were a separate orderable part.

The harness was already there. The engine side was easy. Compressor, dryer, condensor and an idle up solenoid.

The passenger compartment was much worse. Evaporator, a max cool switch, the AC control module and a vacuum operated 1/2 fresh air damper.

Use gloves, lube orings with proper lubercant and no fingerprints.

Like clockwork, the hoses (2) sprung a leak every 9 years. 2x.
FWIW. I am EPA certified for automotive and I have extensive HV
and UHV experience. HV=high vacuum. UHV=Ultra high vacuum

Cake compared to other projects.
 
You would be time and money ahead to simply take a small window AC unit (4000 -5000 BTU) and disassemble it and refit it into your vehicle and use a properly sized inverter to to power it. At worst given the extra power load you would need to add extra battery and alternator capacity of which neither is too hard to do.
 
yiap.... that can be done! and considering the dilusional prises required to install an "normal" car AC (1000 euro + ) , a second alternator, does not even sound hard to install !!
 
Consider this: For 1500W input power the peltier will give you around 500W of heat extraction. An AC unit will give you around 4500W of heat extraction. Choose wisely.
 
you mean a car AC? i know... it cant be compared... car AC system is way better. but the problem is that the prise to fit one on an older car is astronomycal. ( with 1000 euro, i can very well buy the next model of my car., that has AC >_> ). so i was searching for an alternative... not something big neccecery.. just enough to not let me die of heat stroke :p
 
I meant any AC. Heat pumps such as AC and fridges etc. are around ten times more efficient at moving heat than thermoelectric devices given the same amount of input power.
Even if you install the new 1.5kW alternator all you will get will be just a whiff of slightly colder air than there is outside. According to wikipedia a cars AC uses about 3kW of input power.
My guess is fully open windows and fans on full blast will get you more comfortable than a wimpy thermoelectric cooler trying to cool the closed inside of a car while sun is shining on it.
Also, did you check the price on peltiers lately? A 90W peltier costs roughly 50€, so you´d need 16 of them to utilize your alternator. That gets you to somewhere around 800€ for something that will barely work.

Did you check the scrapyards for a car that was rear-ended so that you could salvage the AC?
Edit: the 80W peltiers draws around 135W from the alternator, so you would be able to use only ~11 of them. But still...
 
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I tried something like this for my golf cart a few years ago. Big heat sink connected to a metal post, peltier and a small heatsink with fan for the cold side. I made some foam to direct the flow to my neck and also to recirculate the cold air. It kinda worked, but it was only inches from my neck.
 
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