CMES-Tech achieves first China-developed rotor sail design certification

The tiltable rotor system uses intelligent sensing to maximise wind propulsion efficiency.

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.

In a statement, DNV said this is the first domestically developed rotor sail system in China to achieve this recognition under the company’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.

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, maximising wind propulsion efficiency, while maintaining safety.

Dr Huang Guofu, General Manager of CMES-Tech, said that receiving the certification “demonstrates that our 5 m × 35 m tilting rotor design meets the highest classification and validates our commitment to driving maritime efficiency."

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).

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.