12v fridge/freezer>Battery>Solar Panel Setup

I would say what you have allready mentioned is about right
I run a 80 lt waeco fridge freezer with 2 100 ah batteries and 120 watt solar it works ok but at times 200watt solar would have been nice
Cheers steve

David W28
Apart from the expected ah usage and the days when you get less from any solar, with that factored in, you can also do the following.

Make sure your fridge, whatever size, has more insulation that just the proprietary BAG they supply in fridge deals. The more you can keep ambient heat away from the fridge the better. Ie less AH used each day. A sleeping bag or additional blanket over the fridge compartment will keep the cool in and the heat way.

Make sure it always has a supply of cooler changed air, which is changed by a small fan and if possible some ducting to get the new air to the fridge condensor so it expells any stagnant hotter air which would reduce the efficiency and add to the run time.

I have found having the additional insulation and a computer fan which, may run all the time if needed = 3.6ah of fan run time in 24hrs and will save more than the 3.6ah it uses by making the fridge run less. You may only need it in the heat of the daytime.= less than 3.6ah used.

My first question would be - does the battery also get charged by the car when driving and how much will be driving?

My initial thought is that if you're drawing 80AH/day then you'd want to be supplying more than that on good sun days ... say 100AH, which is going to be in the 250W panel wattage range. Lots of variables involved though.

Hi.

Regardles of your solar and battery capacity Also take a 20a AC charger combined with a small 1\2 tp 1 kw Genny.
100kw of solar no good in 1 week of rain or heavy cloud cover. Believe me. I've bin there.
cover your arse.

With the fridge. I have an 80ltr Waeco. Magic as a freezer, which is what I basically use it for on my three\4 monthly trips.
Find a Ducting insulation supplier.
1 1\2 mtrs of 17mm Solid lagging (silver backed) gives you the BEST insulation avail for these things in back of your car\tray.
My 80ltr in rear of Patrol in summer as a freezer. Uses very little juice. and lifting the cover from the lid there's a full layer of condensation over lid of fridge.
VERY efficient. Cost me around $72 but that's 5 or 6 ish yrs ago.
BETTER than any bags\covers you pay a zillion $$$'s for.

Don't overload with battery's, it's no good if you don't have the solar charging power to keep them up. You'll just find yourself digging in pocket regularly for new battery's.
and Dc to DC charging is just a big con financially.Ac\Dc is much better.