Boats and ships are equipped with sails to use wind power to provide forward thrust. Sails have been around for centuries, but now, these spinning sails will harvest wind energy to power the entire ship.
The idea of using spinning sails is not new. First invented in 1926 by a German engineer Anton Flettner, the rotor sails were installed on two ships, one of which crossed the Atlantic. It has nearly been a century since, and they will be used again, this time backed by Shell’s shipping arm and Maersk, one of the largest shipping companies in the world. The sails installed in Maersk’s ships are a modern take on an old technology.
The spinning sails are large rotating columns, about a 100 feet high, manufactured by a Finish company Norsepower. The sails work on the principle of Magnus effect. When wind passing through the rotor sail accelerates on one side, it decelerates on the other. This movement produces a thrust force that is perpendicular to the wind. The turning of the sails is powered by electricity on the ship to generate a force that brings the ship’s engine to a lower fuel consumption. In theory, the fuel consumption of the ship using rotor sails would be reduced by as much as 10 percent which equates to about a 1,000 tonnes of fuel a year.
You might wonder what is the point of harvesting energy by providing it with so much electricity. If the winds are favorable, the system produces 3 megawatts of power while using only 50 kilowatts itself. Originally introduced in 1926, the spinning sails did not become a success only because they could not compete with the diesel power at that time.
The fuel prices of fossil fuels continue to rise while climate change is evolving to become a havoc for the planet. In such a situation, renewable energies are the need of the hour, making this tech apt for use in the day.