The fan will run by the energy produced by the small solar panel. The sun is the switch and the seasons being the dimmer control. Fast in summer when needed slow if at all in winter when not needed in the Pacific North West. The fan was getting some bright sun this AM and running fast though barely audible inside the TC. If the fan does burn out I'll replace it with a computer fan. Also, I think I'd simply mount the computer fan on top of the screen and use a couple small zip ties to attach it to the screen. I would also fab a ducting to positively vent the air away from the chambered area between the cover and the top of the vent about 2 inches.
