Some people I know that are working on a biosphere, in Amarillo, discussed a cooling system, using a tall round tube of porous cloth and they dripped water from the top down and the principle of latent state of evaporation caused a chilling affect. I am thinking maybe some type of wind tunnel with recirculating
pump soaking up the lack of Btu-s. Heat will alway jump to the cold side.
The system they talked about was in a town square in Europe some where.
I use to have a huge hedge in front of a house I rented. When it was real hot I would set the hose up in the hedge and the air coming through was very cold. In the yard ware a shirt and in front of the hedge you will melt...