[canehdian]

I'll just add to the negative side - I tried this once with my old car with a (full size) lead acid battery.
Did the math and figured it would be ok for 8h - nope. Failed to start upon return.
Obviously an ICE needs more power to start, but the volt is also finicky sometimes on lower charge 12V.

What is work? No power there either? I'd be looking to plug the cooler into grid power if available.

 

[canehdian]

Related question - how well does the cooler work in such extreme heat?

Mine says it only works to about 40 degrees below ambient, IIRC.
That would only be 90 if it's 130 - nowhere near cold!

 

[canehdian]

It does 90 degrees below ambient. It's a full compressor type refrigerator/freezer, not the more affordable peltier type cooler.

I would leave the windows cracked on those days too, so that would drop the temperature at least 10-20 degrees inside the car.

Ahh, ok. That makes more sense.

If you're in the middle of nowhere, you could set a solar panel up outside the vehicle for best angle and exposure - e.g. propped up against the car. Wouldn't have to be limited to inside the vehicle which is not only small and tight, but reduces the light that gets through.