A passenger ship has been fitted with a rotor sail that will enable it to use wind power during trips between Finland and Sweden.

Finnish shipping business Viking Line's M/S Viking Grace will use a 24-meter-tall cylindrical rotor sail developed by Norsepower Oy, another Finnish company.



The sail uses something called the "Magnus effect" for propulsion, Viking Line said in a statement Wednesday. As the rotor spins, passing air will flow with a lower pressure on one side compared to the other, the business said.



This difference in pressure creates a propulsion force that moves the ship forward. Viking Line said that the Viking Grace is the first passenger ship to use a rotor sail utilizing wind power. Its first voyage with the new rotor sail will take place Thursday evening.



The system is automated and will stop working if there are any "disadvantageous changes" in either the direction or force of the wind. Viking Line said that, depending on wind conditions, the sail would cut the ship's carbon dioxide (CO2) emissions by as much as 900 tons annually.



In 2012, international shipping was responsible for 796 million tons of CO2 emissions — around 2.2 percent of total global CO2 emissions that year, according to the International Maritime Organization.



The Viking Grace has been operational since 2013 and is fueled with liquefied natural gas. Viking Line CEO Jan Hanses said the business wanted to "pioneer the use of solutions that reduce the environmental load."