View Full Version : adsorption auto A/C?

21-04-2006, 05:12 AM
Couldn't an adsorption system be used in an auto A/C, running off heat from the exhaust gases? It'll essentially provide free A/C! An electric heater could be used for instant startup.

21-04-2006, 10:26 AM
But the effieency and size should be the problem:)


21-04-2006, 04:56 PM
Hi LC, I guess it's feasible, but you answered you're own question there on the subject of efficiency -it's quite tight for space under the bonnet of modern cars & an absorbtion A/C system would have to be physically larger for the same output. Also, would the working medium put up with the bumping around & G-forces generated when cornering in a vehicle:confused:

23-04-2006, 07:46 PM
I have also pondered using absorbtion for car a/c, i think that it isn't used at the moment as refrigeration technology/ manufacturing is more geared towards vapour compression sytems.
Also Ammonia may be considered too toxic (if leaks in side vehicle) it can also be flammable which may be an issue.
Li Br is also quite toxic.
I think that the future for car A/C may lie in peltier effect electronic systems- less moving parts more reliable (people are fed up with paying for R134a gas top ups on their vehicles)

23-04-2006, 08:02 PM
LiBr isn't toxic but can be quite corrosive, I think there may be problems using this type of system as cars may be subject to a wide range of ambient temps and LiBr may crystalise out of solution in low ambients!!!

26-04-2006, 10:20 AM
The major problems will be space, size and safety. If I am not wrong, to achieve this is adsorption system the cost of the system will go high. Further the operating temperature is varying from - 30C to +50C and also wide range of relative humidity. I dont think adsorption system can operate in these extreme conditions.
people are fed up of paying for R134a, but no other feasible solution has turned out. Till then we have to stick with it only.

09-11-2006, 07:50 AM
I have often wondered about using absorption dehumidification using a combination of Indirect evaporative cooling and Lithium chloride dehumidification .As the free heat is available from the bus or truck engine exhaust and water is not a difficult input any where in the world. Indirect evaporative cooling has been tried for bus air conditioning in Colorado USA.

09-11-2006, 08:15 AM
The LiCl absorption system in combination with IDEC can safely work at operating temperature varying from 10C to +50C and also the complete range of relative humidity occurring at these ambient temperatures . Normally no air conditioning is required I below these temperatures.

The systems can offer advantage of energy efficiency, low GWP and eco-friendliness. Most important advantage will be the lowest Life cycle costs due to considerable fuel savings. consequent reduction in atmospheric pollution during the life of the equipment comes as a bonus.
Of course any water based system will have limitations of working in freezing climate.
With careful design it may be possible to accommodate the system in the space normally used by compressor and drive engine fitted at the back end of the bus.

09-11-2006, 09:07 AM
NH3, LiBr and LiCl *ARE* toxic. Full Stop.
NH3 is asphyxiating and corrosive, Li alhides are corrosive and can cause irreversible brain damage.

I don't want to know what could happen in an accident...

Karl Hofmann
09-11-2006, 01:29 PM
NH3, LiBr and LiCl *ARE* toxic. Full Stop.
NH3 is asphyxiating and corrosive, Li alhides are corrosive and can cause irreversible brain damage.

I don't want to know what could happen in an accident...

The standard of driving would improve...:D

Truth is car manufacturers see AC recharges as a nice little cash cow so there is no incentive to make the current systems leak free.

Look closely at a cars aircon system, which one of us would design a system with alloy pipes supported with steel clips in a salt water environment? and as for those cheap **** O rings.............:mad:

09-11-2006, 02:24 PM
No Nick Name,
I am sure you know ,there is some thing like global warming and Tsunami caused by burning of fossil fuels.

or Do you think carbon mono oxide, carbon dioxide, sulphur, lead are nectar to human beings?
Do you suggest we stop driving cars and shift on to a bicycles?

09-11-2006, 03:03 PM
Do you suggest we stop driving cars and shift on to a bicycles?

Yes, I suggest that all of us possibly shift to bycicles. Riding a bycicle does not necessarily represent a regress. In fact, dutch people ride bycicles for the most of the time, and do not feel themselves as third worldists.

Even if 6 billion people were driving a car, I would still try to prevent people breathing LiCl and LiBr or NH3. This has nothing to do with industrialisation, but with pollution, something that can be disregarded as unavoidable nowadays.

I would not, at any time, reclaim heat from car exhausts (global warming potential reduction) to introduce a new form of risk (chemical hazard). These sort of trade offs are not my friends.

The MG Pony
11-11-2006, 11:16 PM
we need less people! bring on the NH3 and LiBr! less idiots too in the end (I have perm brain damage from idiots & a steel rod as well so I have no feelings for them at all, other then we need less of em!!!!!!)