"Nate Nagel" wrote in message
Is it more energy efficient to open all the windows and turn on a fan, and
let the outside air cool the house off (thus forcing the dehumidifier to
run,) or just leave the windows shut at let the A/C do its thing?

no, this isn't actually a hypothetical... this is exactly what I woke up
to this AM. I chose to open the windows because I like fresh air, but on
reflection didn't know which was really more efficient.

If the windows are open, the energy to run the dehumidifier is about 98%
wasted. Otherwise, fans are cheaper to run than AC