Like your home fridge they have a compressor and fan, albeit smaller. There is a faint noise from a DC fridge when it cycles. It certainly doesn't bother me and this isn't something that I've ever seen mentioned more than once or twice. I guess if you are a really light sleeper it could be a problem but as I said, not a common complaint at all.
If you have an aux battery setup for your needs cloudy days aren't a problem. Once again, those who live in northern climates might be able to speak to this better. These fridges are very efficient. We generally start our rig at least once a day for something and it's never been a problem for us but we are southern U.S.
Not sure what you mean about 12v as worthless (for freezing water bottles???). 12v fridges can be used as freezers. They work very well for this.
Check out this thread:
I am ready. We have used a soft cooler because it fits our truck setup. We need to get ice every day or every other. I am done ready for a 12 fridge. It would be used in the back of my full sized truck. There is a space 16.5" high by 36" wide. I would like to keep it not much higher than...
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