There's gotta be a better way

[Chiefdruid]

It depends on the manifold design, I think. If a 'honeycomb' design could be machined in copper or aluminum, keeping the passages reasonably small, I'd Swag (scientific, wild-a$$ed guess) maybe six...
For a total of 30 amps. Now, this is where I get lost. How does that relate to what the alternator produces? Electrical theory was never my strong suit... lol

[aerohead]

My middle brother once worked at a steel mill near El Paso,Texas.His job was down in a pit,cutting white-hot steel as it emerged from extrusion dies.He wore an insulated asbestos fire suit,equipped with a vortex-tube for cooling.He claimed that it required a remarkable amount of air(pressure and volume) to make the thing operate.I know thats a very subjective comment,buts thats all I have.

[aerohead]

Originally Posted by wagonman76

I think the absorption principle would be a great idea. Like what is used in camper fridges. It uses no evergy except for a heating element to boil a fluid which cools the air inside the fridge and the freezer works well too. Set up the coils inside the car and divert some exhaust heat to boil the fluid. Ive also thought for a long time that this would work well for home cooling too, use the sun to boil the fluid and the hotter the sun beats down, the cooler it gets in the house.

My partner in crime is a boiler operator and baby sits a natural gas-fired turbine-generator(5-MW),which utilizes waste heat to operate absorption cycle chillers for space cooling.The system uses Lithium Bromide as the working medium,and I understand that it will operate at temps as low as 210-degree F.

[aerohead]

Question.Is the air conditioning system on a Prius a non-engine-belt-driven, hermetically-sealed,electrically-powered system? I'll wait 'til I hear back before I go any more stupid.

[Daox]

The Prius uses the main battery pack to power its electric compressor pump. I think this is mainly to provide A/C while the engine is off though.

[SuperTrooper]

It's called an "electric inverter" A/C system. Here is a Toyota slide presentation on how it works:

http://www.epa.gov/cppd/Presentation...20inverter.pdf

[trikkonceptz]

OK after seeing that presentation ... lets break it down to simplest form and argue backwards ...


Why can't we buy a Prius Compressor, make hoses and brackets with the proper fittings and wire it up with a switch we control to a seperate battery or in line with our current battery?

[SuperTrooper]

Originally Posted by trikkonceptz

OK after seeing that presentation ... lets break it down to simplest form and argue backwards ...


Why can't we buy a Prius Compressor, make hoses and brackets with the proper fittings and wire it up with a switch we control to a seperate battery or in line with our current battery?

If the whole point of this mental exercise is to save gas by reducing the load on the engine, then running it off a separate battery makes the most sense.

[chuckm]

A spin off of an idea mentioned earlier: Sterling engines. Use the heat from exhaust gas to power several Sterling engines. Then use the Sterling engines to power directly coupled Sterling cycle cryocoolers.
Additionally, you could also couple the cryocoolers to motors (powered by solar panels) to maintain cooler temps out in the parking lot. This would help lower the time to effective cooling.

[Randy]

Vortex tubes aren't very efficient at all. They only use them when compressed air is handy (like supplied breathing air, or a shop) to get more cooling than the air alone. They're light and simple, but loud and take a lot of air.

A commercial source of them lists BTU/h cooling here. The biggest they have is 6000 BTU/h... the A/C in my Civic is listed at 14800. It also requires 100 scfm, which would take a huge (~30hp) compressor. So standard
A/C is about 10-20 times more efficient, not counting the air-drying effect.

Thermo-electric coolers are also less efficient than refrigerant systems. Also, ice has more cooling for the same weight as a battery, so if you want a rechargeable system, just use a cooler full of ice.

I think the fan seat cover is the closest you'll get to all your requirements.

[Tango Charlie]

Rain on my parade, will ya, Randy?
I figured the (lack of) efficiency of the vortex tube might be what makes it undesirable.

Schlepping ice before every trip just doesn't appeal to me.

I like the fan-cooled seat cushion idea, too. Waiting for Daox's review.
I also like Trik's idea of the electrically-driven Goldwing compressor. Just haven't had time to research it yet. I suppose I could put up with recharging a battery every night.

[azraelswrd]

An ice filled cooler with a small electric fan to blow air over it will do a lot too -- add in some calcium chloride to the ice and now it will act as a desiccant and PULL water out of the air (and solve some of the high humidity issues).

But I still like the absorption cooler only because it speaks to the MacGuyver in me.

[chuckm]

Okay, let me drop a different idea. What if you had a vehicle powered by propane (or LNG for that matter) instead of gas? Tap off the bottom of the propane tank and run the liquid fuel through the AC evaporator set prior to sending it to the engine. When you are not using the AC, use exhaust gas to warm up the evap. In fact, you could use the exhaust gas to preheat the propane to the optimal combustion temp as necessary.

[HaPPI]

The most efficient cooler is the one God built into all of us, evaporation from the lungs, sinuses and skin interfacing to the bloodstream, and what feels best beside. So think in terms of moving the air a little bit (so some kind of fan for one end and maybe the seat cushion gadget for the other) and drying the air in the car when it goes above a certain percent relative humidity. Some kind of chemical humectant that can be re-dried out at home in the microwave would be lots more efficient that current compressor coolers. No moving parts is good. Not sure about cost.

You'd want to keep the air recirculating to keep out the outside humidity. So the air temp might not be 70, but a dry, moving 90 degree airstream will feel cooler to you than a still, clammy 75, you crazy mammal you.

Oh, and tint your windows with heat-reflective film. And paint the car white if it isn't.

I once drove across West Texas in July with no A/C. The key was block out the window to keep the sun directly off ya, and keep the air moving. 110 degrees and it wasn't all that uncomfortable.

[Tango Charlie]

Yup, tinting the windows is definitely on the to-do list.
Doax's cushions might be the simplest solution yet. Or at least the start of an efficient system.

[forgottenmindset]

Yall guys are making this too complicated, lets actually get it done instead of adding tripple turbos, and solar shenanigans

Plan A) Basic, redneck approach

1) Get a 12v oscillating fan from walmart that plugs into the cig adapter.
2) Coil Copper tubing behind it
3) Use an aquarium pump to circulate ice water through the coils
4) Draw the ice water from a super insulated ice box (like the orange gatoraide coolers)
5) Make sure there is an emergency 6 pack in the ice box at all times

Plan B) Nicer approach

1) Use the car's existing blower motor to drive the cool air, and use existing ac controls
2) Stick a copper coil in the duct work, or in the blower motor assembly
3) Circulate the water from the icebox from the trunk, rout it down below the vehicle near like a fuel line, and install a heat exchanger (small heater core) inline to keep the ice water (or whatever fluid) cooler, longer.

You could even put the heat exchanger up near the grill or in a fender well, anywhere it will get cool air.


You shouldn't need to add ice but every few days

[HaPPI]

I'm a fan of fans, TC. I just had a great idea for where it would cool you off best - mounted on your headrest, on the side or top, pointed at the back of your head. A little muffin fan extracted from dead electronics such as a PC power supply is 1) free, 2) 12VDC, 3) draws maybe .3A and could even be run from a 4.5 watt solar cell (WalMart auto dept, around $40, as I recall) on the back window ledge.

With it so close to your ears though, you'd have to pick a quiet one with a slow rpm to not drive you deef. Or if the headrest has an arch to it and a gap between it and the seat like some cars do, put it behind the headrest at the bottom so that the air goes between em.

[chuckm]

forgottenmindset,
I can assure you that it will be more often than just "every few days." I know a little about the gatoraid coolers... Back in my high school days, I played football. Just before school started, we had summer "two-a-day" practices. First practice was ~8:30am, second around 3:30pm. The junior varsity guys had to make the ice water and they were, um, encouraged to get to the ice machine early before the afternoon practice. Why? The ice from the morning practice would be practically gone by the 3:30 practice, even when stored in the shade. (And the last group to make up their jug didn't get much ice.) Sure, we are talking about Louisiana heat. But you're looking at storing your ice inside a vehicle, where the temps can go over 130F pretty quickly.

[forgottenmindset]

Hmm, ok so just add ice everyday


But with the window tint and the cooler in the trunk, I think it would stay pretty cool in the cabin already

What about this, seal the circulating system water (just like the r134 gas is sealed), and keep dry ice in the cooler which has no direct contact with the copper lines, I dunno just thinking out loud here

Also a mabey better idea is to have a really high pressure water pump shoot mist through you blower motor, it wont be enough to make you wet, but it will cool in blowers intake air down tremendously

That's what they do at disney world, they shoot atomized water at fans way high up to shoot cool mystified air at the guests waiting in line. Works amazing.

[Tango Charlie]

No
No
No
and
NO.
I'm not putting a swamp cooler in my car. It's already too humid in there.
And I am NOT schlepping ice before every trip. See requirement #2 in the OP.