According to the Shanghai Shipbuilding Industry Association, on August 15, 2025, the "Gangronghao" 9300PCTC car carrier equipped with the world's first 7L21/31DF-M methanol medium-speed generator set successfully docked at China Merchants Heavy Industry's Haimen base, marking the successful completion of a seven-day sea trial.

The engine unit was manufactured by CSSC Zhenjiang Marine Diesel Engine Co., Ltd., a subsidiary of CSSC Power. To ensure proper verification of the world's first 7L21/31DF-M methanol medium-speed engine on an actual vessel, CSSC Zhenjiang Marine Diesel Engine Co. established deep cooperation with shipowner China Merchants RoRo from the factory acceptance test (FAT) and mooring trial stages. The company proposed multiple optimization solutions for methanol external piping layout, enhancing system reliability from the source.

During the sea trial, the team implemented 24-hour shift monitoring, tracking real-time combustion efficiency, emission data, and dynamic response of the engine unit in methanol mode, while assisting the shipyard in completing multiple key project inspections. Additionally, the team utilized trial intervals to conduct multiple hands-on training sessions, demonstrating in detail the fuel switching process between methanol and MGO/HFO, and conducting fault simulation and response drills for common alarm codes, helping crew members master core operation and maintenance skills.

According to the Shanghai Shipbuilding Industry Association, this successful sea trial verified the reliability, economy, and carbon emission advantages of the methanol medium-speed engine under actual vessel operating conditions. Based on a 50% ordinary methanol substitution rate, the engine will reduce fuel operating costs for shipowners by approximately 11%, strengthening CSSC Power's market competitiveness in the alternative fuel engine sector.