I have ordered some cheapo misting nozzles. I will install them on the front bumper spraying on the condenser and maybe the compressor head to give the AC system a boost in efficiency.
I have also been logging the intake temperature of my TDI. Usually the intake temperature is a few degrees C higher than ambient temperature. When the AC is switched on, the temp goes up 10-15 degs C above ambient.
Hot air is not good for the diesel either, I am hoping this misting will be able to cool things down without consuming a tonne of water.
Something that resembles this: