Each of the two CSOVs will be equipped, from aft to bow, with two azimuth propulsion thrusters, a retractable azimuth thruster, a tunnel thruster, and a combined retractable azimuth/tunnel thruster. Together with Brunvoll’s Propulsion and Thruster Control system, BruCon PTC, this will ensure highly efficient and capable vessels.

North Star’s Chief Technology Officer, James Bradford, says: “Choosing Brunvoll’s complete propulsion and manoeuvring package for our new CSOVs ensures we deliver ships that are reliable, efficient, and future-ready. This partnership supports our commitment to safe and sustainable operations, providing the flexibility and performance needed to help our clients deliver offshore wind projects successfully.

Figure 2. North Star’s new CSOV with two azimuth propulsion thrusters, a retractable azimuth thruster, a tunnel thruster, and a combined retractable azimuth/tunnel thruster. Illustration: VARD

The azimuth propulsion thrusters are equipped with Brunvoll’s latest energy-efficiency innovation, the DL1-nozzle, also known as the “Dragless”. While traditional nozzles experience an efficiency drop at transit speeds, the DL1 maintains favourable hydrodynamic characteristics across a broader operating range. More information about the nozzle and its features is available at www.brunvoll.no/news/the- dragless-nozzle.

“We have a long-standing relationship with North Star and we are deeply grateful for the continued trust they have shown in us.

On the technical side, it is especially rewarding to see the offshore wind industry embracing our combined retractable azimuth and tunnel thruster, a solution we strongly believe in for making vessels more efficient and versatile,” says Bernt Rune Riksfjord, VP Sales at Brunvoll.

The vessels are based on VARD’s 4 19 design, with the following main particulars: length of 87.5 meters, beam of 19.5 meters, and accommodation capacity for 120 persons, along with all equipment required for a CSOV. North Star has secured a long-term charter agreement with RWE for both vessels, which are scheduled for delivery in 2028 and 2029. RWE is one of the world’s largest operators and constructors of offshore wind farms, currently operating 19 wind farms worldwide.