Just started reading about them. Alternative to refrigerant style A/C/. Ancient technolgy, efficient and low operating cost.
https://en.wikipedia.org/wiki/Evaporative_cooler
https://en.wikipedia.org/wiki/Evaporative_cooler
That leaves me out. Florida is nothing but high humidity.
Just ordered 2 table top units that work on that principle.
I bought one of those roll around portable a/c units for my work shop and meh.....I see a lot of people use them to cool their garage/shop in the summer. Just put in on wheels and point it at whatever you're working on.