Out of curiosity, does the wind consistently blow from one direction? Why not orient the fans so they blow in the same direction as the wind?
The wind is fairly consistent, and mostly useless for this case - it blows from the south, so if I have all the windows open, I manage to take hot air from the southwest facing office and blow it through the rest of the upstairs. It doesn't resolve the 10-15 degree difference between upstairs and downstairs, and my furnace is not so equipped to just run the blower without heating (whoever built the house didn't want to run the extra wire to do it, and as I rent, I don't exactly have permission to rewire the furnace).
The peak heat load is in the late afternoon, simply based on the exposure, and the wind starts dying down then as well, so the past few years, it just gets terribly hot in the afternoon/evening and a combination of wind and box fans doesn't do much to solve this.
The change that prompted this build is that this year, we have a baby, so the ferrets (which don't deal well with extremely high temperatures) are in the office, and the baby's room is upstairs (it used to be the ferret room). Blowing hot air through the upstairs and exhausting through the baby's room isn't an ideal way to keep a baby happy, and if the office temperature gets to where it did the past few summers, I'll either have the ferrets spending a lot of time downstairs where it's cooler, or I'll have some dead ferrets on my hands.
These fans have enough power/static pressure to draw the cool air up from downstairs and exhaust it, so I can make use of the "cold sink" down there and the shaded windows with cool intake air. In theory.
If you're trying to get by without AC I would suggest a nice $40 fan blowing directly on you in bed at night. The whole house fans are nice for drawing in cold air at night but they will provide little direct cooling. Kinda depends on your area and situation I suppose.
We were thermally adapted though.
We use a box fan at night to keep us cool at night, and just sleep downstairs if it's too hot. But see above about ferrets and baby.
This moves enough air that I should be able to keep things a whole lot more livable this summer. And, when I move, they're perfectly suited to vent a shed or shipping container or such with solar, a 12v battery, and a timer.
Also, I rent, so a whole house fan or similar is not an option. This is the best I could come up with for my place.