This was a fun wind project and I learned allot about these from researching and building this.  This is a Darrieus type wind turbine.  Probably more in the cycloturbine class.  Most of the Darrieus type turbines don't start themselves and need an external source to start the spin.  Actually it should be stated that they don't start themselves reliably because in certain circumstances they will start and run by themselves.  This project incorporates a tail driven cam that angles the blades in and out of the wind and probably more of a drag type than lift type and will start by itself - reliably.  As soon as the tail is pointed to the wind... its running !  The pictures below show the small unit I built as an experiment into the wonders of these fascinating machines...

This unit was approximately 2 ft tall ( blades ) and 2 ft in diameter and would spin around 450 rpm's in a 20 mph wind.  I've had several different small pm motors attached to it for testing and the best one was an electric  "weed eater" motor which would produce about 50 watts in a 25mph wind.  I was quite impressed for its size and materials it was made from.  It was up for about a year and had survived a 70 mph storm.  I really wish I had a tach on it that day, the only visual on it was the tail and center.  It did however suffer a main bushing seizure the very next day.... A little grease and it was back up and running.

The next one soon to come is a 3 ft by 3ft unit with the same tail driven cam design but incorporates lift on the upwind blade.....

Below are some pictures of the new unit.... First two show the mounting and hinges as well as the push/pull rod for the tail driven cam... I made provisions for 2 setting for the wing control rods.  The farther out the less movement and the closer in the more movement.  Close in there is alot of torque but less rpm and farther out the rpm goes up and the torque goes down.... interesting although I believe the power output is about the same.  It runs just a bit faster than the wind and calculated a TSR of about 1.5 to around 3 with the movement lessened. 

The next one shows the completed unit on a 6 ft ladder.... and it had a 6 mph breeze at the time so it was difficult timing the shot....

I've taken this unit out in a 12mph wind and as soon as the tail points into the wind its off and running.  Doing a performance test using the old "finger dyno" on the shaft I could not stop it from turning... as hard as I was squeezing it simply would not stop... I was impressed... and the dyno was measuring some extreem heat!!  I decided not to go any further with this one and a new project springs to life....  A 4 ft dia x 6 ft tall blades... possibly a 3 bladed unit with the cam design...

We'll see......