Anyone make solar roof vent?

There are some small solar powered vents, but their air movement is quite small.

I added a 4 inch Nicro solar vent in 2001. By 2003 the motor was ticking loudly. more recently I removed the motor, gutted as much of the airflow restrictions as possible, and force feed it with 2 120Mm computer fans, inline and counter rotating.

http://www.westmarine.com/buy/nicro-ventilation--day-night-plus-solar-vents--P012_363_001_516

I'd not pursue this route again if I had to do it over.

Well...Seems these little fan motors draw .9amps or 108 watts at 12V. Would need a pretty big solar panel to make it work to maximum output.

Marine suppliers would have them they are common for boats.