I use 2 to cool my house. Pretty cheap way to do things. They are really common around here, more so than refrigerated air. They work pretty good as long as it’s not really humid. Basically it’s just a louvered metal box, on three sides there are removable doors that contain aspen pads. Water is pumped to the top of the door and allowed to drain across the aspen pad. A fan draws air thru the pads and is cooled/humidified by the water.
https://www.homedepot.com/p/Champion...WC50/100185332