I've never tried it but was told that the 110ac compressor needs at least 2800 watts to run. Myself I never thought the Starcool on shore power was worth the effort to haul much less buy a large generator. That said, I want the inside temps to drop to at least 75* to make it comfortable so YMMV. I just avoid hot humid places. Being able to rid the van of humidity might be of value. It seems that on my van it's almost impossible to cool a hot van down unless I'm parked in shade and start the A/C early before it gets hot. With the top up you almost need to have reflectix over the canvas and all the windows as well. Before jumping on buying a gen, I'd suggest seeing if your system will perform to your satisfaction by testing it on shore power first. JMO
Another note to keep in the back of your head is every Ford dealer I've been to does not understand that the Starcool shares the Ford system. They are always reluctant to charge the system with the necessary amount of freon, but never note what they evacuate out
That stuff is expensive and so they always "steal" what you have, don't put it back, and when you have issues they charge you for what they stole to fill it to the correct level