Fact is fans dont realy make much difference as you will be pulling hot air from inside the van, so if its 30c out and in all you are doing is moving air.
I have done tests of this with a fan in the house, room temps stayed the same, all i was doing is moving air, so unless you have one of the ice aircon units then just wasting your time.
Disagree.
Cooling Fridges
Without fans, air will enter the bottom grill at 30 (ambient outside), absorb heat from the fridge coils, this warmer air moves by convection to the top grill and out to exterior. Taking heat with it.
With fans (either pulling in at the bottom or pushing out at the top) the volume of air being circulated increases and so does the amount of heat removed from the back of the fridge. This means the fridge removes more heat from its interior .
Cooling Rooms
Fans can cool a room when the internal air is hotter than the external air.
Which is the usual situation because
a) Human beings and electrical devices produce heat.
b) After sunset the rate of cooling is greater outside than inside.
To use a fan to cool a room you need to have two opening and place the fan to blow air out of one of them.
Our house in Cuba frequently experiences internal temperatures over 30C.
The windows don't have glass (wooden slats which are not air tight). Placing a fan to blow out of a window makes an incredible difference. The internal air is exchanged for the slightly cooler external air.
Cooling a Person
I do agree that placing a fan in the middle of a room just moves the air around, but even this can cool you down (but not the room).
The air next to your skin is heated by your body temperature and replacing it with air at room temperature results in your skin being cooled.