"...my solar will act as an alternator if alternator goes out." I'm not sure I get this. As you've said, a diesel engine doesn't need electricity to run, so I think what matters is that you're saying that you've got it set up so that the panels also charge the starting battery and thus the rest of the vehicle's electrics are powered.

Yeah, I am not leaving it that way, just wanted to see if it would work. I still think having the alternator and the charge controller on the same block would leave one fighting the other.

I have a total of six batteries and very little load, I don't think I could get to a no start situation if I tried. I think I am up around 600 amp hours.

Hmmm, I might go plug in the block heater just to see what happens....

The point I was making is I learned that it would work, I think you took this too literally.

And I don't have a house battery and a starting battery, my rig is stock with dual batteries and a 140 amp alternator. My rigs starting batteries have to be strong enough to spin the engine to 1700 rpm for it to start so I did not skimp when I bought them. I have four house batteries now with charging capacity for 2 more if I wanted and that is only using the solar set up. If I tied my alternator in, I could really get carried away. There is one advantage to using only solar for all of the batteries in that the alternator does pull a bit of horsepower from the engine. I doubt that load is enough to notice though with a large diesel.

I just went over some math in the last hour and instead of the frankenfridge, I can go with a 3.1 cf chest freezer, run it on a timer switch, 4 on 4 off depending on ambient. I can freeze gallon jugs of water, shut the freezer off and use it as an ice chest as well. When I get a little melt, run it till it freezes hard again. Just have to keep an eye on not freezing what should not get frozen. A bit of trial an error but I think its a go.

My van will be in sunny Baja soon so no worries about running shy, I am fortunate enough to have way more solar than I need. Not a gamer, I don't have a television and the Chromebook draws nothing.