It’s a very odd concept or idea to think that not all sailboats have a sail. Sailboats necessarily sail on the principle of wind propulsion. They harness the wind trapped in large sails. However, some engineers are on to changing the way people look at this traditional sailing concept.
In the year 1920, a German engineer Anton Flettner proposed this “sailboat without sails”. It was a revolutionary idea which threatened to change the basic foundation upon which sailboats were built, which was not easily digested by many. But Flettner designed and created a unique sailboat which used large rotating pillars in place of sails. The 50-ft tall (15 m) pillars rotated at a high velocity with 50 horsepower engines. These pillars utilize the excess power generated in the ship to spin them and the advantage of the wind is taken as an auxiliary power source. This increases the speed of the ship while maintaining horsepower. These rotors were dubbed as “Flettner rotor.”
The Flettner rotors take advantage of a physical phenomenon known as the Magnus Effect – is the commonly observed effect in which a spinning ball (or cylinder) curves away from its principal flight path. Rotating pillars cause air to rapidly spin around the cylinders. On one side the spin travels in the same direction of the wind and pulls the wind down towards the opposing side. Here the Newton’s famous third law comes in picture “action and reaction are equal and opposite.” In this case, the redirected airflow pushes down and therefore causes the object (ship) to be pushed up / ahead.
Enercon, one of the world’s leading companies in the wind energy sector from Germany uses the “E-Ship 1” to transport its huge wind turbine rotors. The ship is designed and built with fuel efficiency as key. Enercon owns this ship which was built at Lindenau GmbH shipyards, Kiel. The alphabet E stands for: ENERCON, Electro-technology, Environment, Economy, Ecology and the alphabet E also implies Energy, Earth, Endurance, Encouragement, Experience, and Experiment.
The ship entered service in the year 2010. It makes use of four Flettner rotors, i.e. -wind energy to cut down fuel costs and also helps to reduce emissions. These four giant 25 meters tall, 4 meters in diameter, rotating, vertical metal sailing rotors (Flettner rotors) positioned two fore and two aft to harness wind energy. Enercon being experts in the wind turbines, their own engineers have designed and developed the main components of this ship. She is 130 meters long, 22.5 meters wide and drought 6-9 meters. E-Ship 1 has proven that Flettner rotors provide a viable, more fuel-efficient alternative to massive shipping vessels. ‘E-Ship 1’ has been recently awarded its class renewal certificate by the DNV GL classification authority.