There's gotta be a better way

[Tango Charlie]

Trik-
That is Really Cool! It looks a little large/heavy for a passenger car, but it shows the concept is valid.
Now whats the smallest compressor on the market? Or something that can be used as a compressor. What about those little 12V compressors that plug into the cigar lighter to inflate beach balls. Could you replace the seals in it to handle refrigerant? Or am I being kooky?

[Tango Charlie]

Ooh! ooh! ooh!
Someone posted a link on bennelson's EV thread about a cheap vacuum pump for his brakes. The link shows how to use a fridge compressor to draw vacuum for vacuum bagging surfboards. But that got me thinkin'. How about using the entire system out of a household refrigerator to cool the car? Put the condenser under the car to dissipate the heat and the evaporator inside. Power the thing with a couple marine deep-cycles and an inverter. Like I said, I suppose I could put up with charging batteries every night. Need to get into the habit if I ever build an EV.

[hondaworkshop]

I'm eager to hear how the seat Daox has bought works out.

I'd like one that gets its air from a tube connected to your lower footwell air vent in the car... then there's no extra drag on the alternator from the additional 12v device.

The pricipal appears to be a supportive matrix inside the cover to keep it from collapsing, but will allow airflow... some kind of stiff batting or beads would work. The backing material is solid and airtight like vynil, the front material that faces your back is perforated or a loose weave. Air is fed iin from a remote spot and it escapes onto your back.

I think I want to make one of these now.

[trikkonceptz]

Originally Posted by Tango Charlie

Ooh! ooh! ooh!
Someone posted a link on bennelson's EV thread about a cheap vacuum pump for his brakes. The link shows how to use a fridge compressor to draw vacuum for vacuum bagging surfboards. But that got me thinkin'. How about using the entire system out of a household refrigerator to cool the car? Put the condenser under the car to dissipate the heat and the evaporator inside. Power the thing with a couple marine deep-cycles and an inverter. Like I said, I suppose I could put up with charging batteries every night. Need to get into the habit if I ever build an EV.

You may be on to something there ... visit a dump site and get a hold of an old fridge or even a water cooler set up, like the ones in offices. Either do maintain cold temperatures and are likely compact enough. If you do not carry passengers often I still think it may be best to set it up on the passenger side floor simply because you can pipe it into the recirc vent right there on the floor and use your a/c ducts to cool you off. Also it would leave the power cord really close to the cars 115v jack. I would then weigh the amperage draw against that of the car's a/c compressor as to whether or not you would even need a seperate converter and batteries.

[SuperTrooper]

Originally Posted by trikkonceptz

You may be on to something there ... visit a dump site and get a hold of an old fridge or even a water cooler set up, like the ones in offices. Either do maintain cold temperatures and are likely compact enough. If you do not carry passengers often I still think it may be best to set it up on the passenger side floor simply because you can pipe it into the recirc vent right there on the floor and use your a/c ducts to cool you off. Also it would leave the power cord really close to the cars 115v jack. I would then weigh the amperage draw against that of the car's a/c compressor as to whether or not you would even need a seperate converter and batteries.

Ummmm... You can't put it in the passenger compartment. Where would all the heat go???

I'd bet that the belt driven compressor on the cars system would be more efficient than using an alternator, converting it to DC than converting it to AC while stepping up the voltage. The AC electric motors on those units also pull some serious amps when cranking up the compressor. My fridge is only 2 years old and the kitchen lights dim when it cranks up.

I think we are starting to overthink this. Yes, I'm sure somebody could rig up some Rube Goldberg setup that would work, but the complexity and weight would relegate it a mere mind exercise; not something practical on a common production basis. The tractor A/C unit is practical because it eliminates the running of the diesel engine overnight and the additional weight is of little consequnce on something that heavy. A car already has little space available for what would be essentially a redundant system.

I'm not sure that Tango Charlie's original request is doable:

"1. Be more efficient than the current standard compressor/refrigerant system. i.e.; not affect mpg.

2. Not require recharging or servicing before every trip.

3. Be contained within the vehicle. (Can't be ruining aerodynamics, now.)"

He wants a system that uses no energy to perform a task that takes considerable energy. Then he says you can't recharge it every day, so all the battery powered ideas are out the window.

This has become a tail-chasing exercise.

[Tango Charlie]

I really like Mr. Goldberg. He's so entertaining.
My intent of requirement #2 is to avoid being an 'ice toting freak' before every darn trip. Recharging a battery overnight at home in the garage is totally do-able.
It will be a tightrope to walk to gain any efficiency. In my case, I'm not too terribly concerned with some extra weight, as I do very little driving in town (stop and go) during my commute.
Trik found he could drop 300lbs by removing the rear seat and interior, so there's always that.

[EVDRVR]

Very Neebie here. Some thoughts.

I have a Solectria Force electric vehicle. Solectria converted the Geo Metro to 100% EV for those not familiar. The Force is a very efficient vehicle.

The a/c in my 1997 Force uses a electric motor to drive a slightly smaller compressor than the original, rest of the unit is stock Geo a/c.

Electrical requirement to power the permanent magnet 120V motor, which turns the compressor, in the Force is about 1125 watts. So you are looking at only about 1.5 hp.

The a/c plug in any factory vehicle I've ever seen are usually good for around 60-140 watts of modified sine wave AC. Good for plugging in your really small stuff, useless for powering a compressor motor.

The Force a/c System works well up to about 90-95F degrees and then it is marginal. (the same may be true for a ICE powered Geo)

We get numerous above 90 days in the central valley area of CA so I have had a on going effort to increase my air conditioning output/effectiveness.

Tinting the windows with the best heat rejecting film I could buy helped a lot. Also had the upper part of the windshield tinted a bit wider than the usual factory tint band. This tinting "bought" me a good 5 degrees of usefulness. The Geo started with no tinting or close to none. now it is tinted except for the forward viewing area of the windshield. I was able to find heat rejecting tint that still meets CA visibility requirements for all windows. This is a EV so running something that is using up amps and not producing the desired benefit is for me very frustrating. The a/c is definitely range limiting. The car is white so I have that going for me.

That "Nite system" recommends some of the same batteries that store power in my Force. You are looking at about 60 lbs each for batteries and not including the other stuff. A lot of gas using weight to carry when your not using the a/c. and a lot of work to install and remove if you don't want it in there in the winter. The Deka batteries recommended cost about $200-250 each in CA. the only way this product is probably something to consider is that the name is applicable to using less a/c....drive at nite when it is cooler if you have a choice.

The Force measures power usage much more precisely than most of us can see in our ICE powered vehicles. (Even with a Scangauge II.) I can tell the difference between being alone and having a passenger of equal weight. So frequently the a/c unit is using more power than than the propulsion unit. Like when stopped or slowing.

The good news in the Force. It uses less power to cool the air than it does to heat it. Fortunately for ICE powered vehicle's an abundance of heat is readily available in the waste stream.

If you can find a compressor that fits and is more efficient and just adequate this might save a few precious drops of fuel. Keep the heat out. Keep the cool in and pre-cool the car if you have the ability to do that for short trips.

Love the discussions on Ecomodder so I'll go back to lurking now. You're the best.

FWIW my personal experience is that driving a EV will improve your hypermiling abilities and nothing saves gas like not using it.

EVDRVR

[Vince-HX]

being an "ice toting freak" is the best solution iv'e come up with

just gotta get high tech about it

[orange4boy]

To keep things cooler in the parking lot, I use a $1.49 plastic thermal blanket on the outside of the vehicle attached with rare earth magnets, although you could use some strips of that flat sign magnet

This makes me a tinfoil totin' freak. I'm good with that. It works like a charm and you can be seen from space. (for signalling purposes you know)

If you go with deep cycles and an electric compressor, you have the added benefit of saving on alternator drag so you would have a mpg gain.

[Tango Charlie]

EVDRVR, welcome! Please don't go back to being a lurker. I really appreciate your input. Go ahead and introduce yourself in the Introductions section of the forum. I'm sure many members would love to discuss your Solectria Force. Have you seen bennelson's homemade metro EV conversion?
The info about your Force continues to make me think that a small compressor powered by a separate battery may be worth looking into. The battery would only need to provide 70 to 80 minutes of run time to cover my commute.

I need to get off my duff and tint my windows. That'd be step one. What name brand of film did you use, EVDRVR? I'm a little leery of the stuff at AutoZone. The purplish tint looks so tacky. Anyone know how dark I can go in Indiana?

orange4boy, I've been thinking of an outer cover. Using magnets is a stroke of genius. I think using one in the winter would eliminate scraping ice and snow, too.