The zero breeze is cute, but at 1,100 btu I suspect you'd want at least 3-4 of them for a van. Even then you'd just be "less hot" rather than "cool". Looking at their pages, it does look like they are starting to be real, though still in small numbers.
Not really an answer to the original question, but this is the reality of what you can easily get today:
My van came with an ancient roof top unit (13.5k btu) from its days as a news van. Yes, they are heavy. They do use the same cutout size as the fantastic fan, so they could be swapped back and forth.
Recently I mostly made mine work with a single eu2000i generator. That was a neat project, I'll write up a post on that sooner or later.
I resisted carrying, or even owning a generator for a very long time, but after camping with this setup in 104 degree weather, I'm converted. All I want to figure out now is how to carry the generator all hooked up and ready to go.
'99 EB ex ENG KSWB news van, low rent 4x4 conversion (mostly fixed by now), home built interior.