Oil-Free Screw Blowers Aid Efficient Performance
Variable Speed Driven (VSD) oil-free rotary screw blowers are to play an integral role in an innovative air lubrication system designed to give larger vessels up to 8% in fuel savings.
At the heart of Silverstream’s system is the need for reliable air compressor technology which is where Atlas Copco’s VSD screw blowers come into the equation.
“The system relies on a constant and dependable supply of compressed air,” said Stephen Potts, Head of Supply Chain at Silverstream.
“The Atlas Copco ZS55 oil-free screw blowers provide this – giving us the right combination of cost, performance and reliability.”
Designated as an ‘innovative technology’ under the IMO’s Energy Efficiency Design Index (EEDI), the Silverstream system is seen by many as integral to the future of shipping by reducing Green House Gas emissions.
Applicable for both retrofit and new-build installations, the patented system reduces frictional resistance between the water and the hull surface, reducing fuel consumption and associated emissions.
It does this by employing a series of carefully positioned air release units (ARU) on the ship’s hull near the bow, which then creates a carpet of micro-bubbles. This carpet reduces drag, minimising the amount of fuel required to propel the vessel forward.
“Why give full flow when sailing at a low speed? That would be a waste of energy. That’s why ZS units are equipped with VSD technology; you can perfectly follow an ‘optimal flow demand curve’ and tune your flow to your sailing speed,” said Rob Boughton, business development manager for low pressure technology at Atlas Copco.