9. New Construction Methods
New Construction Methods for the Twisted Savonius VAWT:
With the 32 side approximation cutout model being so close to the “true” twisted savonius shape, it is predicted that the 32 side approximation could be used to construct a full size wind turbine that was fully operational. Four separate 32 side approximations would be scaled up to about 2-3 meters (6-10 feet) tall and traced onto a semi-flexible fabric of some sort. These shapes would be cut out and stretched around a pre-built frame with five semi-circles, as in the side view model made in Geometry Expressions. The proximity of the 32 side approximation to the actual turbine shape would make this possible, likely without making all of the folds in the model. Of course, using an approximation model with more sides would make this method better and better, but time constraints have limited the current investigation to the 32 side model. Regardless, this method should greatly reduce the cost of building the turbine—this new method enables construcion of the blade (but not the generator and electrical equipment) for as little as $100 for a 2-3 meter turbine (depending on the fabric)—while comparable designs have been priced in the range of $15,000-$25,000 (including electrical components) for a similar size. This significant price reduction could make seeing wind turbines on roofs much more common. Below is an animation of the Geometry Expressions Twisted Savonius model operating on top of a building.
To learn how you can make your own small model with one of the cutout approximations, click here.