Air Lubrication System (ALS)

An air lubrication system reduces a ship’s frictional resistance by releasing a carpet of microbubbles under the flat of the bottom, separating the hull from water across part of the wetted surface. Air release units near the bow are fed by compressors, and the net fuel saving runs 5 to 10 percent depending on draft, speed, and hull form, less the compressor power drawn to make the bubbles. The IMO recognizes ALS as an innovative energy-efficiency technology in the EEDI framework, so a fitted system lowers the attained EEDI. Silverstream’s system, fitted on over 100 vessels, is the reference installation.