The Savonius Super Rotor !

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We all know what wind chargers look like or do we? In this article Michael Hackleman introduces a very effective wind energy device most of us have never seen or even heard of. The Savonius or S-rotor was introduced to this country way back in 1924 but suffered stiff competition from the already perfected multi-blade farm windmill and the "more exciting" high-speed propeller-driven generator. Now Earth mind -a California farm research center that specializes in alternative energy experiments-has revived the S-rotor in a very impressive fashion. With the move back to the land and the homesteader's soon to be everybody's-need for a, source of energy other than Con Ed, the time has come to reconsider the generation of electricity from the wind's power and many of us are doing just that. Until now, however, only one type of wind charger has been readily available: the propeller-driven generator or alternator. (Such rigs used to be called "Stuart mills" and I've found it convenient to use the term in this article.)

The props that spin the generators on conventional wind plants vary in number of blades (two, three or four) and in the complexity of their aerodynamic surfaces. Differences notwithstanding, however, the lower end of the price range for even owner-built Stuart mills hovers stubbornly around $400 plus.

Here at Earthmind we've been trying to break through that price barrier by experimenting with a little-known alternative wind device which is low in cost, simple to construct and boasts several other distinct advantages over the Stuart mill in general performance and safety of operation. This unit is the Savonius rotor often called the S-rotor because of its appearance.

The Savonius rotor is easily made: Just split a cylinder equally through its length, offset the halves by a distance equal to the radius of the original form and secure the segments to end plates the width of the new diameter (see Fig. 1).. Then insert a rod through the center of the assembly, fix its ends in bearings, and the device will rotate when exposed to the wind. If you use soft drink, beer or other small cans for your rotor, you'll have a toy but start with 55-gallon drums stacked three on end (out of phase with one another) and even at low wind speeds the power from your creation will surprise you.