I went home during lunch so I could see what my Solar Hot Air panel on my garage…

I went home during lunch so I could see what my Solar Hot Air panel on my garage was doing. The indoor/outdoor thermometer I put into the panel died today, and putting in new batteries didn't help. I had to scrounge around for another thermometer and found a candy thermometer in the kitchen. I put the thermometer in the hole coming from the panel into the garage and ate lunch. When I came out, it was measuring 98 degrees. The panel was getting heavily shaded, about half the panel in some shade, 1/3 was in heavy shade. By the time I took the photo of the thermometer, it was reading closer to 92 degrees. These things appear to be very shade sensitive.

The first thing I noticed was how much the clear plastic cover bowed out. Between the fan blowing air into the panel, and the heat causing expansion, the plastic was bowing out probably 2 inches. Additionally, the landscape fabric which was stapled in tight, was saggy like an oversized sweatshirt.

When I got home about 6pm, I checked the temperature of the garage, it was 50 degrees still. It normally follows the outside air temperature pretty closely, so being 10 degrees warmer than the outside 40 degrees is pretty good. I desperately need to insulate the garage, if only to stop it from being so drafty!

I want to find a 15 watt, 12volt PhotoVoltaic panel to run a computer case fan I have. At that point, heating the garage would become free energy. $80 seems to be the going price for the solar panel. An alternative would be a thermoelectric generator, but they aren't marketed for this application, so it's really hard to read the specs to figure out what I would need. It appears that I would need $60 worth of those (3) in order to work. These would also bleed heat out of my panel, so they are a 2nd level option.

I still need to trim out the panel, which would make it look better as well as seal up the plastic on the front face.