Here's another solution........ This Bonaire profile evaporative I have converted to 12 volt. It has a car thermo-fan hooked up to a 12v 15a controller, and a pond pump hooked up to a 12v 5a controller. Water supplied via an internal float valve. The controllers are mounted on a 3"x5" plywood board inside the front panel, coupla holes and screws. The thermo-fan inside it's housing, is pre-drilled and tek screwed. Water flow and fan speed are separately variable for maximum cooling(hopefully). The fan and controller I used in the van for ages previously. It is currently running on the 80 watt panel, with a slagged-out old battery as a power sink, but I will eventually hook up a Mini-maximiser to it-no battery required,( but you can still use one/some for night time use).