Best solar powered car cooler?

I would like to add a 12-volt car cooler to my outfit and use solar to power it, as an alternative to plugging it into the car cigarette lighter.

Any experience or thoughts?

Thanks.

Really, If I understand it correctly, you don't really waste you battery using the cigerrete lighter, while the car is on at least, because while to engine is running, it is charging the battery, and the main reasons there is a battery is for all the electronic things in the car, and most importantly starting the car. Unless you wanted to use it out of the car, or when it was off, then the battery would probably be better. Do you already have an electric cooler, if so then all you would have to do is put the panels on the top of the car or werever you plan on putting them, and then getting a converter, and a transformer(you can get them off ebay) to change whatever you got from the solar, to match with whatever the cooler needs.

I have a small 12-volt cooler, it takes 4 ½ amps to run it, that is a serious amount of power for a solar panel to produce. That comes to about 55-watts, you need a panel that is more then this to make up for clouds and shade. It would take about $800.00 to get a good 75-watt panel. A 75-watt panel is also somewhat large, about 2 foot wide by 6 to8-foot long.



Solar power is great, but it’s still very expensive when you want any real power out of it.



PS a 12-volt cooler plugged into a car cigarette lighter socket without the car running will kill the battery enough that the car will not start in just a few hours of the cooler running.

Also, check the specs on the cooler. Some I have looked at only cool to 40 degrees F below ambient temperature. That may or not be acceptable for your situation.

FWIW

1. I do NOT want to run a cooler off the car main battery except maybe while the car is being driven at freeway speeds.

2. The cooler can be very small. I primarily want to store a few things that otherwise might go rancid.

3. 40 below ambiant would be fine; cooler would be better.

4. A solar panel made to fit on the dashboard and cover the windshield would be ideal.

Well I read about a car (BMW or Mercedes maybe) that instead of a glovebox (who still has driving gloves anyways?) has a cooler? You may want to look into this if you don't use your glovebox or if you can move what you have in it out of it.

No dashboard size solar panel puts out 4 or 5 amps, this is what is required to run one of these coolers. No car battery is going to run it long before it goes dead. A constant 4 or 5 amp draw is going to kill it.

These coolers are only practical if you have a running car or a 110 volt plug for the cooler.

They would work with a solar panel and a battery if you had a 60 or 75-watt panel.

Or a generator.

I do not know hw to do the power math, but I was hoping these little guys might draw so little power that solar was realistic:

Koolatron
http://koolatrononline.stores.yahoo.net/koolatron-d07-portable-kool-sport.html

Vector 5 liter
http://www.cooler-store.com/rubbermaid_travel_cooler_and_warmer_149_prd1.htm

I know that the new Dodge Caliber has the cooled glove box feature others might as well

To do the math I use electrical laws I learned a long time ago. (Ohm’s Law and Watts Law) you can do a search to find a web page that will do the math for you if you are not familiar with them. All you do is fill in the spec’s you do have (Volts, amps watts or resistance) and it will give you the answer. It takes some basic electronic understanding to know what to ask it and what the answer means.


The mini-fridge I have is small 8 inches square by 14-inches tall. It draws 4 ¼ amps. That’s 51 watts (12-volts times 4.25 amps = 51 watts) But when hooked up to a running car it gets 13.8 volts from the alternator output. That pushes the watts up to 62 watts. As it would with a solar panel as they are over-ranged to make up for lack of sun and the load put on the panel. So I would guess that my mini-fridge would need a 75 watt panel (100 watt would be a lot better) to run the fridge. $800.00 for a solar panel to run a cooler that can only hold 6 cans of pop is kinda expensive for most people.

Also a nice thing to keep in mind when buying a solar panel is the watt rating and how it’s arrived at. They get the rating by putting the panel in the sun on the brightest of sunny days. Under normal conditions you will get clouds & some shade. This can and will cut the panels output in half or more. So a 50 watt panel becomes only 25 watts for 30% of the time you are trying to get power out of it. The best way to make good use of a solar panel is to have it as part of a 12-volt (or 24 or 48 volt) system. For a DC system you need a battery, solar panel, charge controller, possibility an inverter, larger wiring as DC voltage requires heaver wires with the same voltage then AC does. And a lot of other small things to make it work. Most of these things can be made easily from parts from other things. But the one big expense is the solar panel.

So, you can't get there from here? Meaning there is no small solar powered car cooler that actually works well off a reasonable solar power source?

Don't use solar power - It causes global warming. It also will make the sun burn out faster.

Compare a chunk of ice to one of those thermoelectic coolers. The TE device will use about 50 watts to produce about 15 watts of cooling. One kg of ice will provide the same rate of cooling for six hours. A 1 kg gel cell battery will run the cooler for about a half an hour.