nieko nežinau apie subj, bet pats principas pakankamai veiksmingas:

http://www.viesa.ca/products.asp?pid=80

Cooling is generated by vaporized cool water delivered by a self-contained
electrical motor. During operation it only consumes water and it makes no 
use of
internal combustion engines, nor does it use chemical coolants or emit gases 
into
the atmosphere. The unit is equipped with a water pump located in an 
auxiliary
tank which takes water to the evaporator. A biturbo blower pushes the 
exterior
air to the interior of the truck forcing the air through the evaporator and
therefore cooling the warm air. The exceeding water backs to the water tank.