I have been working on this project FOREVER! Well… at least it seems that way. I have always been the kind of person who REALLY hates being hot, and for years I have wished there was a better way than just a window shade to keep your car from getting so hot when it is parked out in the sun in the summer. BEHOLD THE SOLAR CAR FAN!

I actually did come up with this idea all by myself, but of course once I started talking about it my friends showed me an infomercial for a solar fan that already existed. For about a second I was disappointed that someone beat me to the punch, but then I remembered that I had already decided that I wasn’t going to pursue a patent on this idea anyway, so what did I care? Besides, mine was going to be better!

Before starting this project my entire electronics knowledge base was what little I learned from wiring up lighting on my model train set as a kid. I designed my solar fan to be as electrically simple as I could make it so it would be a good first big-boy project for me. I still had to acquire a little knowledge though, and my friends Harper, ROCK-IT The Robot, and several guys at American Science and Surplus helped me out a lot.

The way this fan works is by drawing air in through the vacuum attachment, that is pinched in the mostly closed window, and pushing it into the hot car through the metal screen on the bottom of the Tupperware tub. I think it will work best if more than one window is open, but I’ve got one more redesign before I can know that for sure.

Part of the reason that it took so long for me to finish the fan is that it is really a summertime gadget, and summer is my busiest time for performing. The other reason it took so long is that in addition to being electrically simple, I wanted the design of my fan to be as elegant as possible, and easy enough to use that even a normal person would think it was worth the effort.

The first design did not include the vacuum attachment and was more awkward than I really wanted. I had been trying to think of a better way when good ol’ Harper showed me a fan that another do-it-yourselfer had made. Thanks to both of you.

My fan as it is now works, and is almost as elegant as I wanted, but once I turned it on I discovered that the motor I put in is not powerful enough. I got another stronger one that is a LOT bigger from American Science and Surplus, but I think it will fit. I’m hoping to install it tonight or in the next few days.

Most of the work on this project was done with fairly simple tools without a fancy workshop. In fact, the final assembly was done entirely in a dirty motel room in Niles, Michigan in between shows with nothing but a drill, a soldering iron and a fat Swiss Army knife. I’m kind of amazed I didn’t get arrested as a terrorist bomb-maker. Earlier on I did use some slightly fancy metalsmithing hammer skills on the rig that holds the solar panels though.

One of the things that I discovered through experimentation is that the angle of the solar panels to the sun is really critical. Even just 10-15 degrees can be the difference between power and no power. All the solar fans I saw that were commercially available did not have angle adjustment for the solar panels. That flexibility adds some complexity, but I think it’s really worth it unless you enjoy parking your car at crazy angles in the Kmart parking lot.

Read on if you want to make one of these yourself (or you just like parts lists):

Here’s a lit of all the parts I used and how much they cost. Estimated costs have an asterisk* after them.

  • brass strip $1.79 (hardware store)
  • Zoob construction set $9.95 (American Sci. & Surplus)
  • SPST micromini switch $2.99 (Radio Shack item #2750624)
  • model plane propeller $.63 (Hobbytown 2.5 x .75 direct drive prop, item #GWSEP25086P)
  • little zip ties $2.00* (hardware store, pack of 100*)
  • chrome cooling fan cover $0, salvaged
  • Ziploc reusable food tub $3* (grocery store, pack of 4)
  • 2 1volt, 200mA solar panels $3.25 ea (American Sci. & Surplus)
  • heat-shrink tubing $2 (American Sci. & Surplus)
  • motor $1.00 (American Sci. & Surplus, 1.5-3voltDC 100mA, item #33348)
  • vacuum attachment $5 (vacuum store, I should have been able to salvage one and yes I’m still angry about it)
  • pop-rivets $1.39 (hardware store, pack of 15, you will also need pop-rivet gun)
  • piece o’ wood, salvaged
  • screws, salvaged
  • brass wire, salvaged

Total cost: $36.25

Total cost really (just the parts I used, not the rest of the multi-packs): $20.01

I’ll post an update when I get the new motor installed.