We built a 1000 watt wind turbine to help charge the battery bank that powers our offgrid home.

It's a permanent magnet alternator, generating 3 phase ac, rectified to dc, and fed to a charge controller.

The magnets spin with the wind, the coils are fixed, so no brushes or slip rings necessary.

For complete instructions go to: 

http://www.instructables.com/ex/i/B9ECDD4243EF1029AC23001143E7E506/?ALLSTEPS