won't be the last I promise
You need a genset even if you can fit multiple kW of panels on the roof.
You will not be able to run the aircon off the panels **and** recharge a large bank at the same time, unless going to maybe 2-3kW of panels.
Running off genny will be needed for sub-optimal conditions, so the large investment in solar+batteries+inverter in the end just **reduces** your genny runtime.
At the cost of having to park in full sun all day.
There are plenty of 16000 btu aircon units that will run off a Honda eu2000i, get that sorted first.
Then work on the battery bank, figure 100AH **additional** capacity for each hour you want to run between genny cycles. Total incremental cost over the above will be several thousand USD at least.
The biggest challenge will be getting the energy you take out of the battery bank, back in. You need shore power or a genny running nearly as long as the aircon did, that huge very expensive battery bank just buys you some time shifting.
Need **lots** of solar for the long tail back to 100% Full, unless the bank is LFP, which is **very** pricey.
But solar will only give you 10-20% of the total energy needed, and that's only with a huge roof space to mount it, much bigger than the aircon will cool even with very tight sealing and 2-3" insulation.
If you need to run the aircon same time you're re-charging the bank you need double the amps input from mains, power or gensets.
See? The issue is **total energy needed** per 24 hours, voltage is really irrelevant!
Saving on the cost of the inverter will be trivial, and wiped out by the extra cost of a DC-powered aircon unit, which will likely be 48V, add other expenses then converting from that to 12V for everything else.
So stick with AC-powered aircon units to save some money.
Frigomar, Webasto, Dometic. . .