Although, as has been said, you really have to work out what you
need for your own situation.
For example, we have a 85L compressor fridge and from our experience (with that) would alter the above statement to:
"Your fridge would Like a 100w solar panel & then work out what you need for everything else
As you can see, it's horses for courses: summer vs all year round, what size fridge, what else will you have running, what will be your average overnight drawdown (in amp hours)? A bigger battery will then give you a bigger buffer (to some extent) for when you get some days with little or no sun).
100% Agree & I was throwing out there what a fridge can get through, All be it in winter & allowing for weather that isn't great.
IMO the answer is so complex that most if not all people, Can't work out what they need, Given that no one can work out what Rain/ cloud cover/ Sunlight there is going to be to charge battery's, Let alone look into the future & work out how long & where we will be staying in the years to come
I was making the point that even 160 to 200w isn't a lot.
If we hit a Newbe with most of the little things like not all panels are created equal,
The type of glass that they have & there ability to stay clean,
The size wiring that is used both before & after the controller, So as to not have to much voltage drop.
The thousands of controller's out there in the big wide world, That are not created equal & don't charge the battery's the same way or the same amount for a given panel size, The charge voltages of multi stage controller's vs the one's you can't set.
All this without getting into battery size & type, Wiring size & length, voltage drop to the fridge, Inside & out side temp of the camper etc.
Then this for all the other things we use.
There would have been a heart attack involved
We do however know that the deeper stage of discharge we take our battery's the more life we take out of them, ( Once again depending on what type of battery to what effect it has )
The more solar you have the sooner in the day that the solar can hold it's own & stop the discharge of the battery, Lowering the depth of the discharge the battery, So there for not taking as much life out of the battery.
How deep people are ok with taking there battery's down to is up to them, As at the end of the day it is them that has to pay.
Given that bigger solar panels IMO are cheaper than bigger battery's, I will always choose to go for what some people would call over kill on solar, So I can get the best out of a bad day.
But as you have rightfully said, Everyone has different needs & it is up to them to work out what they are.
Murray and Niki.
2007 Mitsi Fuso Canter 3.9 Turbo Diesel , 630w Solar, 500 A/h Lithium batteries
Maxxair Vents, 130L 12v Fridge. 240v Inverters 2500w,190L water.
We also have a second 1 of these campers with a tow bar that we rent out.