Completely ineffective.
I used to leave my car parked in an unshaded lot for my ten-hour shifts, from seven in the morning to five in the evening. I had breaks around 9, 12:20, and 3, plenty of opportunities to see first-hand how cool the car would be after letting this fan run during different times of the day. No matter how I tried (with the weather stripping, without, installed on either side of the car, front, back window, etc.), my car was always a stuffy oven.<br />The first problem is that the solar cell doesn't have power most of the day. It's too weak to pull much energy unless the sun is almost directly perpendicular to the cell. Even the black vent duct shades the cell once the sun moves far enough overhead.<br />The second is that the fan simply does not move enough air, even when the motor is spinning at full blast. I don't know if the fan blades are just poorly made or if the motor doesn't have the power, but the result is the same.<br /><br />As an experiment I made sure to visit my car when the fan was operational. You can hear the fan running (though it is quiet), and you can feel warm air coming out. But it's simply not enough, not while the fan is running and certainly not when it's idle (which is most of the time)<br /><br />My advice? Skip this gimmick. Buy a cheap shade for your windshield and leave your windows on each side open by about half an inch. You will get FAR better results.
Rating: 1 stars