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Container Ship

Why use Air Lubrication? 

The IMO Energy Efficiency Design Index (EEDI) Phase III levels seek CO2 emission reductions on new ships of at least 30% by 2030. Air Lubrication Systems (ALS) has been designated as “Innovative Energy Efficiency Technology” by the IMO that can help meet these targets

How does Air Lubrication Work? 


ALS reduces the resistance between a ship hull and surrounding water by producing micro air bubbles distributed across the hull surface. The reduction in boundary density reduces the frictional resistance working on the ship’s hull. 

What fuel savings can Air Lubrication achieve?

Wartsila recorded fuel consumption savings of up to 15% in their 2008 Boosting Energy Efficiency Presentation. 

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What is the GreenTech Energy Air Lubrication System?


Greentech Energy’s patent-pending system is based on Bernoulli's Principle and includes a dedicated pump that provides a liquid jet gas compressor or ejector with motive seawater from the ocean to compress relatively lower pressure air into microbubbles. The seawater draws the lower pressure air into the suction chamber before entering the diffuser mixing throat. The mixture is then violently compressed into microbubbles and discharged into the ship boundary layer through dedicated hull openings, reducing frictional resistance.

What are the benefits of the GreenTech Energy ALS System?

Ejectors have been successfully used to produce microbubbles for many years in the oil and gas and water industries within Dissolved Air Flotation (DAF) units to improve the efficiency of solid and oil separation in water. The benefits of using an ejector ALS, include:


  • Controlled microbubble size.

  • Reduces hull fouling impact.

  • No moving parts.

  • Simple Installation.

  • No ejector maintenance.

  • Lower cost.

  • Minimizes hull modifications.

  • Increased reliability.

  • Performance-tested before delivery.

  • Small footprint and weight.

  • Improved efficiency (performance tests required).

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