Computer hard drive windmill

I started with the spindle motor from an old hard drive. I figured it was a pretty nifty use: the permanent magnet 3-phase motor should make a cool generator, plus it will supply 3-phase power. Unfortunately, my hopes of hitting 20 watts with it are pretty much dashed.

I cut out a Compuserv CD into fan blades, heated it to bend them, and mounted it to the motor. With the air hose, I managed to get to 600 RPM (a far cry from the rated 5400 RPM) and dumped 30 volts into 1000 ohms for a power output of 0.9 watts. Indeed, the power rating on the drive indicated it was only supposed to draw about 6 watts total, so my chances of getting past 5 watts or so is not too likely. However, even 5 watts over 20 hours would provide me with enough power to run 10 watts of lighting and other stuff for 10 hours or so. At least the 100 watt-hours generated each day is far more than the 50 watt-hour capacity of the batteries I'm looking at. Oh, then I broke the blade.

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