Flettner rotor sea trial
To meet UN’s climate goals, many ship owners consider installing Wind power on their vessels. Several wind assistance technologies are available on the market, for example “Flettner rotors”. But how much power saving can a Flettner rotor provide, in real life? One way to find out is to conduct a sea trial.
In May 2021, the general cargo vessel Annika Braren was equipped with a rotor sail from the German company Eco Flettner. In September, it was time to make a firm assessment of its performance. SSPA’s Dr Werner conducted a sea trial together with Captain Jürgen Mehrens and his crew on Annika Braren in the waters north of Gotland.
- We were really lucky with the weather, Dr Werner says. The wind speed was between 9 and 12 m/s and the sea was moderate. Perfect for rotor sailing.
The ship owner Rörd Braren and the charterer Ahlmark were very co-operative to take the ship out of the normal operation for the seven-hour test. The results will now be analysed at SSPA and reported during the autumn.
This work is part of the EU Interreg North Sea Region project WASP https://northsearegion.eu/wasp/. Apart from Annika Braren, four other vessels with wind assistance technologies are evaluated in full scale. Scandlines’ ferry Copenhagen was the first one out. The sea trial and fuel saving assessment were presented at the RINA Wind Propulsion Conference in September this year [https://www.rina.org.uk/Wind_Propulsion_2021.html].
- There is still no standard for how to perform sea trials for wind assisted ships. We are developing new methods as we go, Dr Sofia Werner at SSPA explains.
To develop recommended procedures for wind assistance sea trials is one of the tasks for the newly started ITTC Committee for Wind Powered and Wind Assisted Ships. SSPA chairs this committee, and the experience from Annika Braren and the other WASP vessels will be valuable input to the committee work towards new Recommended Procedures.
Flettner rotor sea trial
To meet UN’s climate goals, many ship owners consider installing Wind power on their vessels. Several wind assistance technologies are available on the market, for example “Flettner rotors”. But how much power saving can a Flettner rotor provide, in real life? One way to find out is to conduct a sea trial.