Savonius Wind Turbine: Power Output & Lever Arm Effects

[dlbeeson]

Given a certain sized Savonius Wind Turbine, for example, using a 5 gallon bucket (about 12 inches in diameter and 14 inches tall) cut vertically in half, the standard configuration has the two "scoops" either touching at the central vertical axis, or partially overlapped.

Would moving both "scoops" out horizontally, away from the axis, for example, with the center of each scoop mounted at the end of a 4 foot bar, with the main vertical axis in the center of the bar, 2 feet from each bucket, improve either the power output at a given wind speed, or the sensitivity to start rotation in slower winds?

In general, what might be gained or lost in separating the scoops (bucket halves) more, increasing the radius, and hence the lever arm?

 

[CWatters]

I believe separating the scoops would increase torque and reduce rpm. Probably make it start at a lower wind speed.

 

[dlbeeson]

I believe separating the scoops would increase torque and reduce rpm. Probably make it start at a lower wind speed.

Thank you CWatters. That is what I was thinking. Will build and experiment.