I have been eyeballin' one of these for sometime now.
https://rollibot.com/product/mini-split-ac-room-air-conditioner/
This unit would likely take a 2kw generator to run, at least for initial start up.
I have run a 5000btu window unit on one of those hundred dollar, 900 watt, 2 stroke generators that harbor freight sells.
It tripped the breaker on the generator a couple of times when trying to get it started for the first time but after a few resets the AC would start without tripping
I am sure there is a wicked current spike upon initial start up that is tripping the breaker.
Once you power it up a couple times some extra heat and maybe some extra juice from some onboard capacitors is enough to start it up without tripping.
It ran like this for 4 or 5 days with an auxiliary boat tank hooked up for less frequent fill ups.
I have been working on a set up for my 4x4 vanagon (if I ever get it done) that consists of 1200 watts of solar and 250 amp hours of Nissan leaf batteries in a 24 volt configuration.
By my math, in a properly insulated van, this should easily be able to keep you cool all night.
I suppose if it was really hot and really humid and the AC had to run full blast all night and you slept for 10 or 12 hours it would be pushing the batteries' limits but that's where the backup generator would jump in to save the day (or night in this case).
Well, that and I assume, if you slept for 12 hours, some portion of that time would be daylight at which point the solar panels could come back to life.
I do suppose if you used up all of your batteries overnight and needed to use the AC in the daytime then you would probably have to resort to the generator to get the battery charged back up for the next night.
You could just use the generator in the day when everyone is awake and the batteries (hopefully being charged by solar if the weather is nice) at night
It's all about having supplemental systems working in harmony that really would make all this work.
Then you could live off grid for a long time.
A slightly warmer setting and a fan can work wonders as well.
Surprisingly, a lot of people still believe that a solar charged battery powered AC will never work (well at least on some other forums that I frequent) but all it takes is some simple math to see that it is totally possible.
Even after posting that math some people are still not convinced.
It might not be as cheap as a generator and window unit but it is possible.
Heck just a decent fan may be all that is needed to take the edge off
I have used a 5 inch USB powered fan running on my cell phone charging battery pack thing while tent camping a few times.
I set it up to point at my upper body and generally sometime in the early morning hours I find myself covering up a little bit.
I never actually measured the temp but this was Ohio in peak summer temps so it was probably 80 ish with 80% humidity.
Definitely not as cozy as AC but it gets me by and about freezes my wife out if she happens to get any of the breezes from it.
As far as generators and noise, I rather prefer the dull hum of some of the new small inverter generators as I can not sleep in total silence.
You can also build simple boxes that will still quiet down even the most quiet generators.
To be honest a campground is not the first place I would stop and set up if I was looking for total piece and quiet.
Complaining about noise at a campground is like complaining about umbrellas at the beach