DNV awards CMES-Tech TADC for new 35m tilting rotorsail design

DNV has granted a Type Approval Design Certificate (TADC) to CSSC Shanghai Marine Energy Saving Technology Co., Ltd. (CMES-Tech) for its new 5m × 35m Tilting Type Wind Assisted Rotor System. This is the first domestically developed rotor sail system in China to achieve this recognition under DNV’s WAPS rules (ST-0511). With this certification, the system is confirmed ready for installation on DNV classed commercial vessels and marks a major milestone for China’s green-shipping technology industry.

As shipping faces mounting pressure from fuel costs and emissions regulations, the demand for reliable and efficient wind-assisted propulsion systems is rising globally. Recent years have seen a growing number of WAPS solutions certified by DNV, including fixed or tiltable rotor, wingsail, and suction sail systems from providers around the world.

The CMES-Tech tiltable rotor system features a retractable and adjustable design, enabling the rotor to adapt to varying draft and clearance conditions, and retract during cargo operations to avoid interference with deck/hatch operations or port infrastructure. The system also integrates intelligent sensing and automatic control to adjust rotor operation based on real-time wind conditions, maximizing wind propulsion efficiency, while maintaining safety.

Dr. Huang Guofu, General Manager of CMES-Tech, said: “Receiving the DNV TADC is a landmark for China’s green-shipping industry and a strong validation of our design’s maturity, structural integrity and operational practicality. It demonstrates that our 5 m × 35 m tilting rotor design meets the highest classification and validates our commitment to driving maritime efficiency. We look forward to working with DNV as we continue to innovate and deliver solutions that can deliver economic and environmental value to shipowners worldwide.”

As part of the TADC process, DNV’s classification experts reviewed all mechanical, structural, and electrical design documentation, and assessed the system’s suitability for shipboard application under realistic operational and environmental conditions. The review confirmed that the design of the CMES-Tech system meets the requirements of DNV’s WAPS technical standard (ST-0511).

Mr. Chen Keng, DNV Vice President and Area Manager China South, said: “With increasing demand for energy-efficient and emission-reduction solutions, WAPS technologies offer immediate, tangible benefits to shipowners. The awarding of this TADC to CMES-Tech means we add another option to the growing portfolio of WAPS systems that have been assessed to the industry’s leading rule set, building further confidence in their readiness for real-world use. We congratulate CMES-Tech on this achievement, which underscores our strong collaboration on enabling the broader deployment new energy enhancing technologies.”

The rotor sail prototype has also successfully passed a rigorous 120% overload structural test, demonstrating its robustness under extreme load conditions. Looking ahead, CMES-Tech will proceed with detailed installation planning and sea-trials to validate the in-service performance of the new system.