My 100ah comment was just a round number off a 300w panel w/ 5hrs of light 300w/14v*5hrs = 107ah ~100ah (one would assume you'd porbably be running MPPT with those levels of wattage so you won't be throwing away the extra volts). It had nothing to do with your battery size mentioned earlier and was more towards the "250-300W minimum" comment you made. Even with only 1 hr of good light 300W of solar is going to throw off ~21ah, I just don't see how small camper and trailer rigs would need anything of that nature and that is what I was calling attention to.
I agree with each person needing to decide whats best but if you're in a sunny spot I'd give solar a tad more credit than you are. 50ah over 3 days is ~17ah a day. Assuming you can get 5hrs of good sun and your using a basic PWM controller 17ah/5hrs*14V= 47.6w of adjusted solar, 47.6*18V/14V= ~60watts of panel most likely needed. That is smack in the 30-100w range you were blowing off. You can pick up an 80w panel and a Morningstar Sunsaver SS-6 for ~$200. That isn't quite as our of reach as you might think and if you're only using ~17ah a day that will extend your 3-4days much more than 5 even in less than ideal light. 80w/18V=4.45amps (not I didn't account for MPPT here, this would be PWM numbers), 4.45amps per hour of good light. Only got 2hrs of good light? Well now you're only having ~8ah deficit a day, you've just doubled your stay. A little over 4hrs and you're coming up even.
But yes only around 30W doesn't do much unless you're a much lower ah user, which someone without a fridge might be (the OP didn't say anything about a fridge so I was just showing him a cheaper source for a panel/controller in the range he was looking at).



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