Darrieus wind rotor, Heroldstatt Kids T-Shirt

This vertical design rotor was erected by the Dornier company, better known for building aeroplanes, on a windy spot near Heroldstatt on the Swabian hills in 1990 as an experiment to measure how efficient it was at producing electricity from wind power. The big advantage of the design (which originates from 1931 from the French engineer Georges Jean Marie Darreius) was that the moving parts were at ground level and therefore easy to access for maintenance. Unfortunately, it became clear that this design was less efficient than the more familiar rotor blades attached to a horizontal turbine, and as far as I know this is now the only example of the Darrieus rotor still standing in Germany. It no longer runs. More information on the Darrieu...