Neat design (especially the blades), but I have these issues:

1. It's only $30 of parts if you get most of the parts for free (especially if you consider the mounting hardware).

2. You're screwed if you can't get hold of those alu sheets from a printers shop - I have no idea where I would find them.

3. There's little info on how to turn the rotary motion into electrical power, and no info on expected power output.

4. The published design, with one bicycle wheel, does not look strong enough (a later video shows a new design with two wheels, but then you have alignment issues). There's a big bending moment on the axle, and those old-fashioned freewheel hubs are known to snap axles (I've snapped one myself).

5. None of the electrics are weatherproof, but that's par for the course for homebrew stuff!