A portable air conditioner or window unit can keep your place nice and chill even during the hottest summer months. But if you’re looking for a way to stay cool without blowing up your energy bills, consider these ways to air out your home without cranking the A/C.
Best for: A single floor
If there’s a breeze, open a window on the side of the house receiving the breeze, and another on the opposite side. Using a smaller opening on the breeze (intake) side and a larger opening on the exhaust side will increase the airspeed through the house. Strategically open and close doors to force air through the rooms you want to cool. If there isn’t a breeze, you can use fans to create one. The intake window should be on the home’s coolest external wall; put a fan in the window facing into the room to suck in cool air. A fan facing out an open window on another external wall exhausts warm air.
read more at: https://www.popularmechanics.com/home/interior-projects/a21272176/energy-saving-house-cool/