These days green enery is a hot item. I already have a solar panel but the idea of getting energy out of the wind i find very interesting. So i decided to build a windmill to experiment with.

The main part of a windmill is the alternator. This has to be a very efficient and light turning device. On the internet there is enough information on this subject. I decided for a design that has two turning magnet disks (the rotor) and between them a disk with coils in which the electricity is induced. This is a 3-phase alternator in star connection. The magnets are so called 'rare earth' magnets. They are very strong. When disks with these magnets snap together with your fingers between...