DSME is First Korean Builder to Win AIP for Rotor Sail on ULCC Tankers

rotor sail design approval in South Korea
DSME construction yard in South Korean (file photo)

Published Mar 22, 2021 4:05 PM by The Maritime Executive

Daewoo Shipbuilding & Marine Engineering reports that it has become South Korea’s first shipbuilding to obtain approval from a classification society for a rotor sail system. DNV has reportedly issued the shipyard an Approval in Principle (AIP) from DNV for the application of the eco-friendly ship technology to ultra-large crude oil carriers and LNG carriers.

One of the oldest eco-friendly auxiliary power technologies, the rotor concept was first demonstrated nearly 100 years ago by German engineer Anton Flettner. Mounted to the deck of a ship, the rotor contributes additional power from the force generated as the column spins in the wind. DSME says that it provides a significant advantage compared to its volume and that it is easy to install and manage. 

DSME says that as part of the process it analyzed the application of this system demonstrating that it will result in fuel savings of more than 5 percent based on the Energy Efficiency Index (EEDI), which the International Maritime Organization (IMO) uses as an energy saving evaluation measure.

"The company is actively conducting research activities to cope with the increasingly strengthening global environmental regulations," said Choi Dong-gyu, head of the Daewoo Shipbuilding & Marine Engineering Research Center. "We will focus on development and devote ourselves to continuous research."

Rotor sails began to reemerge as a promising technology in the past decade as the first modern projects sought to incorporate them into new ship designs. Major shipping companies including Maersk and Viking ferries have recently been testing the use of the technology on a vessel in operation. In addition, a number of design concepts have been presented to apply the technology to modern shipping. 

Norsepower Rotor Sails recently announced that it has signed its sixth agreement for the installation of its technology. The installation which is planned for this year will be the largest to date on a bulk carrier. Further, Oldendorff Carriers, one of the world’s leading dry bulk lines, recently announced that it will participate in a joint development project to design and test wind-assisted propulsion technology for its dry bulk carriers. The project, scheduled for completion in 2022.

Korea Shipbuilding and Offshore Engineering in January 2021 announced that it had received a different AIP from DNV this one coming for a wing-sail auxiliary propulsion system for ships. The wing sail propulsion system is similar in that it is also attached to the deck but it is a solid sail rotated to catch the wind to provide auxiliary propulsion to the ship.

The Korean shipbuilders have been working to accelerate the use of auxiliary technologies to enhance their future competitive position. DNV notes that it has developed a standard for the certification of wind-assisted propulsion systems. DNV recently introduced a new additional class notation, WAPS (Wind Assisted Propulsion System).