Every child knows that mankind has sailed across the seven seas with 100% wind-powered ships for centuries. So it's a no-brainer that a wind turbine maker developing their own cargo ship would want to utilize wind power as a means of propulsion somehow. The engineering challenge was to find a way to adapt the age-old concept of sailing to the requirements of 21st-century cargo shipping. In a nutshell: a modern sailing vessel has to be reliable, it can't be manpower intensive, and it has to be superior in a meaningful way.
To solve this problem, the Enercon engineers embraced the concept of "rotor-ships" developed by the German engineer and inventor Anton Flettner during the early 1920s. Flettner utilized the "Magnus effect" to design an unconventional concept of propulsion for a sailing ship. The "Magnus effect" is the phenomenon whereby a spinning object flying in a fluid creates a whirlpool of fluid around itself, and experiences a force perpendicular to the line of motion. In the case of the rotor-ships, the spinning objects are huge metal cylinders and the "fluid" is the wind. The resulting force was utilized to produce propulsion for the ships.
First Rotor-Ship, the "Buckau"
In 1924, the first experimental rotor-ship was built. In February 1925, the "Buckau" made its maiden voyage from Danzig in modern-day Poland across the North Sea to Scotland. The two "Flettner rotors" of the ground-breaking vessel operated without problems even in the stormiest weather conditions and were significantly more efficient than traditional sails.
One year later, Flettner's rotor-ship crossed the Atlantic sailing to the US via South America. When it arrived in New York, it was quite a sensation and the rotor-ship proved to be a technological success. A few months later, a second ship was built with "Flettner-Rotors". This time, it was a 90-meter-long cargo ship called "Barbara". It underwent trials in the Mediterranean by the navy of Weimar Germany, where it received positive reviews and operated without problems. According to the ship's captain, the 3 Flettner-Rotors of the cargo vessel generated up to 600 hp of additional power and could be used 30-40% of the time during their journeys. Considering that the ship's conventional engine had 1,100 hp, that's a 54% boost! (source of the photo)
Please continue reading at Source: Clean Technica (http://s.tt/195QY)
