Backyard Wind Turbine, Part 5: Building and Installing the Wind Turbine (2 of 5)

Project Table of Contents

1. What kind of energy should I harvest?
2. City ordinance and neighborhood considerations
3. Installing the tower base
4. Building and securing the tower
5. Building and installing the wind turbine
   • Selecting the type of turbine 
   • Choosing AC or DC (this article)
   • Prototype, aka “Mark 1”
   • Building the “Mark 2”
   • Video of the finished Mark 2 in action
6. Wiring up the electrical connections
   • Wiring
   • Preventing “reverse flow”
   • Regulating and controlling the charge
   • Batteries
   • Dump Loads
7. Afterward…

AC or DC, Which to Choose?

As far as efficiencies go, you’ll want to stick to 3-phase alternating current. This lets you have a relatively far run from your head (the turbine itself), down the pole, through your conduit, and into your shed/box/garage/basement (wherever you’ll have your batteries and inverter). If you’re building your own you can rebuild an alternator or make your own stator. This is by far the more geeky way to go. WindBluePower and WindStuffNow are your stopping points on how to build this kind of generator. If you do go this route, you’ll have 3-phase AC coming down your tower, and into a rectifier (think “inverter in reverse” that will convert your 3-phase AC into DC power, ready to go into a charge controller, then into your batteries and loads.

I opted for DC for a few reasons. First off, I had a DC treadmill motor on-hand to build my first prototype with, second, I had some fairly thick gauge wire that I could run down my 30-foot tower so I’d minimize loss. And lastly, it was the most price effective way to go (read: cheaper than the other ways).