In Phoenix (well, MESA actually, but the same area) I installed a hyper-efficient attic fan on the 'hot side' attic end blowing out... exhausting the hot attic air onto the hottest (west) side of the house, drawing the slightly cooler air in from the other side. I set the thermostat on the unit to run automatically any time the air temp in the attic was over 140F / 60C.
During the worst weeks of July, it generally shut down around 10pm. That means the attic temp was JUST UNDER 140F at 10pm. If I'd set it any lower, it probably never would have shut off.
Even with the little bit of electricity I was spending nearly all day, it did a better job than the passive wind turbines 'cos the damned wind turbines NEVER moved on the hottest days when you needed 'em the most. On average, I saved about 20 bucks of electricity every month in the summer with the electric attic fan, not counting the reduced wear & tear on the AC compressor.
Since the fan DIDN'T run in the winter, what little heat reached the attic wasn't exhausted by a passive turbine, so I probably got another mild savings in comparison to passive turbines. The fan paid for itself within the first two years, not counting the winter 'bonus'.
I purposely bought a house facing south, with the garage on the west (hot) side to block as much heat as possible because of the basic construction. The back patio shaded the kitchen, family room and master bedroom. Deciduous trees and shrubs on the front side helped cool it there, as well.
Still, all things considered, it's HOTTER 'N HELL in Phoenix in the summer! I'm damned glad I left.