Wärtsilä EnergoFlow

Vessel owners are facing the twin challenges of ensuring compliance with the IMO’s Energy Efficiency Existing Ship Index (EEXI) and Carbon Intensity Index (CII) measures while also needing to improve operational efficiency in order to remain competitive. Wärtsilä EnergoFlow is an innovative pre-swirl stator that improves a vessel’s propulsive efficiency by creating an optimal inflow for the propeller, reducing both fuel consumption and emissions.

Wärtsilä EnergoFlow creates optimal inflow for the propeller by guiding one side of the stern flow in the opposite direction to the propeller rotation, generating pre-swirl. The solution consists of multiple curved fins and a ring attached to the ship’s hull to prevent the power losses that typically occur in a propeller’s slipstream.

    Key benefits
    • Improve fuel efficiency by up to 10% in combination with a new propeller design and Wärtsilä EnergoProFin
    • Reduce NOx and CO2 emissions
    • Take steps towards EEXI compliance through minimum speed reduction
    • Improve vessel CII rating
    • Fast return on investment of one to two years
    Technical info

    Scope of supply

    • System design, supply and class certification
    • Trailing Edge Modification (for fixed pitch propellers)
    • Installation drawings and instructions
    • Design interface with the shipyard or ship designer
    • Supervision by Wärtsilä technicians during installation


    • New, optimised propeller (optional)
    • Scale models of EnergoFlow and/or propeller for tank testing purposes (optional)
    Applicable for vessels with Fixed Pitch Propellers and Controllable Pitch Propellers of Warstila  and another make.

    Articles and whitepapers

    Complying with EEXI – how to speed up...

    Time is running out for vessel owners to comply with the IMO’s EEXI and CII measures. What are the pathways...
    • Article

    Wärtsilä’s energy efficiency solutions...

    Delphis’s ice-classed container ships were fitted with Wärtsilä propellers and propeller caps, improving...
    • Article

    Saving the maritime industry, one energy-saving...

    Wärtsilä’s partnership with MARIN and Grimaldi on the LeanShips initiative has yielded exciting fuel...
    • Article

    Why propulsion efficiency is the name...

    By focusing on optimising the lifecycle efficiency of ships, Wärtsilä's role as a full-service provider...
    • Twentyfour7. article

    Wärtsilä EnergoFlow boosts propulsion...

    Wärtsilä has launched its latest energy-saving device for ship engines, a next-generation pre-swirl stator...
    • In Detail article

    Wärtsilä EnergoFlow - Robust and Reliable

    Wärtsilä’s energy efficiency solution, EnergoFlow is a path-breaking solution enabling the...

    Download whitepaper »



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    Related products & services


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    Controllable Pitch Propeller

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    Improve your vessel’s propulsive efficiency and reduce your fuel consumption

    Fixed Pitch Propellers

    Contact us

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