Project Table of Contents
- What kind of energy should I harvest?
- City ordinance and neighborhood considerations
- Installing the tower base
- Building and securing the tower
- Building and installing the wind turbine
- Selecting the type of turbine
- Choosing AC or DC
- Prototype, aka “Mark 1” (this article)
- Building the “Mark 2”
- Video of the finished Mark 2 in action
- Preventing “reverse flow”
- Regulating and controlling the charge
- Dump Loads
Prototyping (aka, the “Mark 1”)
What started this whole project and launched it from a wild hair into something I could actually do was an old treadmill that we inherited when I got married. The treadmill broke one day and I couldn’t fix it. It was too big to just throw away, so I had to take it apart (read: break it into smaller pieces). In so doing I “liberated” the DC motor, and it was a big one. This motor sat on a shelf in the garage for years until I finally stumbled upon the incorrectly named “Chispito Wind Generator.” There were my plans. I went to work building the thing with reclaimed PVC pipe, a scrap of plywood, a new pumping flange and nipple, and a length of steel tube. Within a few weekends I had a “functional” wind turbine. All in all, materials for the head and tail assembly cost me under $20. I didn’t have a tower or even a post to mount it on, but I was on my way. The assembled head and tail assembly sat in my garage until our good friends donated a tetherball pole to us. I now had a “prototyping tower.”
I placed the head and tail assembly atop the 10-foot pole… and waited for the wind. And waited. And waited. Finally we got a breezy evening and watched the blades slowly spin. It was beautiful. Until the blades unscrewed the hub and fell to the ground. I’d cut my blades the wrong way – rather, I cut my blades such that they spun the wrong direction, you want the rotation to tighten down on the hub, not loosen it. Good to know.
So I cut and mounted a new set of blades, then mounted them atop the pole, and waited for the wind… And waited.
Finally we got a gusty evening. I ran outside and eagerly hooked up my multimeter. The blades were spinning pretty quickly, but the output peaked at 2.4 volts. To charge batteries I needed at least 12 volts. I was devastated, but I finally knew why the treadmill had stopped working: the motor was shot. I left the “Mark 1” atop the pole just so I could see it spin.
By this point in time I’d learned enough about the whole system that I decided to “upgrade” when I built my “Mark 2.”