Psychic makes cloud square

"My name is T. Chase and I am a cloud shrinker."

"Please excuse the strange sounding voice, it is necessary to speak like a low tone "humming" sound to get the proper brainwaves for cloud psychokinesis."

Question for meteorologists and, of course, engineers: what would the energy requirements be, roughly, to shrink a randomly shaped cloud of volume n to the largest hexadedron it could contain, either by physical movement of the visible condensates or evaporation.

I just have this feeling that anyone who could do this could also, like, boil a kettle in a couple of seconds, instantly powerwash their car, make watermelons explode, etc.