MDinana...please do... I posted to another forum, and the discussion came up concerning the laws of conservation of energy...that the small high velocity flow would would become less efficient powering the larger fan lower flow, as opposed to using it directly...for me it is a perciption of the cooling effect of the lower flow...and the larger area cooled by the ceiling fan vs. practical mounting of the smaller fan...am currently running a run time test with a new alkaline D cell...