Here in the UK we get a few days were we wish we had air conditioning, but no where near enough to justify the cost, I do however have various vents around the house, and feel I ought to have some more.
obvioulsy theres a few in the kitchen to meet the regs for gas oven etc. and a dryer vent but ive no drier, but that vent is in an alley wich is always in the shade so is quite cool at the moment.
sitting here too hot to even think of what to do a google search on, I thought of having a selection of reversable fans about the house, and a control system that sense the inside and outside temp at each fan.
thus putting each fan in a direction that brought the house to an optimal temp possible with no actual active heating or cooling as such.
ive also seen systems where hot air has risen to the ceiling is driven down to the floor through a tube to help reduce the cost of keeping a house warm in the winter.
is there much mileage in this?
I seem to have huge amount of PC type fans in my junk box. and a realy neat 1" fan from a photocopier wich just blew out the ionized air. its realy silent and surprisinlgy powerfull, and would be easy to put through a wall.
ofc the problem here is they are all one way.
My brother has a more sphisticated air system with a heat exchanger. but only one exit/entry point to the outside. but he built that into his house wich he built himself.