We have a large swamp cooler on our roof it uses a 3/4 hp motor and has a large cage to blow air. It works well if the temp is not over 105 and the humidity is not high. I think in a vanagon a swamp cooler would put out to much humidity�but I have never tested the theory. I know in our house paperback books will curl but it does not bother electronics . We do not have A.C. in our van and have not for 29 years. We camp at the coast or the mountains and travel in spring or fall or winter mostly. Sun shirts help and will deflect� UV rays. I may look in to AC for the van in the future.
Bill Witz 84 Westy Tiico Very Old Paint