For the first time in nearly a century, a ship is about to be fitted with a set of “spinning sails” that harness the wind to help power it across the ocean—a technology that could significantly green up the process of trans-oceanic shipping. As The Guardian reports, the spinning or rotor sail was first invented in 1926 by German engineer Anton Flettner, who installed them on two ships, including one that crossed the Atlantic. The “sails” are actually rotating columns that work with the prevailing winds to generate forward thrust for ships. This modern trial of a new take on old technology is backed by Maersk, Shell’s shipping arm and one of the largest shipping companies in the world. One Maersk tanker ship will be outfitted with two of the nearly 100-foot-tall spinning sails – which are manufactured by Finland’s Norsepower.
How, exactly, do they work? The spinning sails employ a principle known as the Magnus effect, in which wind passing through the spinning rotor sail accelerates on one side, while decelerating on the other. The movement of the sail generates a “thrust force” perpendicular to the wind. Electricity from the ship powers the turning of the sails, and the force generated by the sails lets the ship’s engine throttle back to lower fuel consumption. Using these sails could theoretically cut the fuel consumption of global shipping by as much as 10 percent.
Add to that the fact that, when the winds are right, each of these sails can produce about 3 megawatts of power while only requiring 50 kilowatts to operate, and the ships also have a source of renewable energy on board. The rotor sail only failed during its first go-around in the 1920s because it couldn’t compete with diesel power at that time. Now, as the price of fossil fuels is on the rise and climate change is here, this technology could be ready to set sail.
Via The Guardian
Images via Norsepower