Chinese Air-Lubrication System Cuts Fuel Use by One Metric Ton Daily
A second-generation bubble-lubrication system developed by the Shanghai Merchant Ship Design and Research Institute has demonstrated a 5% net energy saving during sea trials, according to Interesting Engineering. The technology uses compressed air to reduce hull friction, potentially saving approximately one metric ton of fuel every day for large product and chemical tankers.
Context from Industry Pulse
The shipping industry is increasingly looking toward fluid dynamics and hull-surface engineering to meet efficiency targets without redesigning primary engines. By utilizing the principles of supercavitation—originally used to propel torpedoes at high speeds—this Chinese development addresses the specific challenge of hydrodynamic drag. The shift from manual to automated control systems reflects a broader engineering trend toward real-time optimization. Because the system is fuel-agnostic, it serves as a bridge technology that can be applied to current fossil-fuel vessels as well as emerging green-propulsion platforms like ammonia or methanol-powered ships, provided the net energy savings outweigh the electrical load of the compressors.
Engineers in China have successfully adapted drag-reduction concepts from high-speed underwater munitions to improve the efficiency of commercial shipping. As Interesting Engineering reports, the Shanghai Merchant Ship Design and Research Institute developed a system that injects compressed air beneath a vessel to create a layer of microbubbles. This gas-liquid mixture reduces the frictional resistance between the hull and the seawater, allowing the ship to maintain speed with less propulsion power.
The technology was recently tested during a five-month trial on a 50,000-tonne product and chemical tanker. According to Interesting Engineering, the results showed a net energy reduction of roughly 5%, a figure that accounts for the electricity consumed by the air compressors. This efficiency gain translates to a daily saving of about one metric ton of fuel for a vessel of this specific size and class.
This second-generation iteration introduces significant upgrades over a prototype tested in early 2022 on a container ship. The new version features an intelligent control system that monitors the vessel's speed and draught in real time to adjust the volume of air released. These automated controls are intended to optimize energy use across varying sailing conditions, addressing the manual limitations observed in the earlier design.
Compatibility with various fuel types makes the system a flexible option for the maritime industry. Interesting Engineering notes that the bubble-lubrication hardware can be integrated into ships powered by liquefied natural gas, methanol, ammonia, or electricity. While the institute has not released a full breakdown of the trial data, the successful deployment on a commissioned tanker suggests the technology is ready for broader commercial application.
The Industry Pulse Bottom Line
This automated bubble-lubrication system offers a scalable method for reducing maritime fuel costs and emissions. Its 5% efficiency gain provides a significant operational advantage for large-scale tankers across diverse global shipping routes.