Wärtsilä Low Loss Hybrid (LLH)

The introduction of Wärtsilä Low Loss Hybrid (LLH) and its integration with a conventional diesel or dual-fuel engine generating sets, offers significant efficiency improvement by running the engines on optimal load and absorbing many of the load fluctuations through batteries. The system is designed and integrated to optimise the overall operation of the vessel.

The power and energy capacity of the battery should be suitable to allow the engine to run for most of the time on optimal loads. The system is designed and integrated to optimise the overall operation of the vessel. A key element is hybrid control algorithms for load sharing between units and efficient power and energy management.


    Fuel saving and reduced emissions
    Wärtsilä Low Loss Hybrid ensures substantial reduction in emissions, and supports a sustainable operation with different fuels. The yearly fuel savings have proven to be between 10-20% depending on type of engines and configurations.

    Optimized engine operation
    Low Loss Hybrid supports operation of engines at optimal specific fuel consumption

    Reduced engine transients
    Low Loss Hybrid will be used to reduce transient loads in engines. Transients will increase fuel consumption and emissions.

    Increased redundancy and efficient operations
    Power redundancy requirements require engines to run at low loads. When energy storage is accepted as redundant power the engine will operate more efficient on higher loading.

    Reduced maintenance
    Due to more stable operation and less running hours the maintenance cost will be reduced.

    Increased performance
    Vessel performance will be more responsive due to the fast power response from the energy storage system. This may also increase dynamic performance in critical operations.

    Technical data

    Related references

    Press releases

    E&A acquisition

    With the acquisition of L-3 Marine Systems International (MSI) Wärtsilä broadens its offering within the area of Electrical & Automation. We now have extensive experience in supplying automation, navigation, communication, electrical distribution, electrical power & propulsion, dynamic positioning, sonar and underwater communications, entertainment, safety and security technologies, for a wide variety of vessel types. These products and systems are well regarded in the cruise & ferry, commercial cargo, offshore and oil & gas markets as well as with navies around the world.

    The products of Wärtsilä SAM Electronics, Wärtsilä Valmarine, Wärtsilä Lyngsø Marine, Wärtsilä Dynamic Positioning & Control Systems, Wärtsilä JOVYATLAS EUROATLAS, Wärtsilä Elac Nautik, Wärtsilä FUNA and Wärtsilä APSS, are well known and respected throughout the industry. With our resources in Norway we can now proudly claim that this makes Wärtsilä the marine industry’s leading E&A provider. We can now provide our customers with the latest technologies and greater opportunities for meeting their present and future needs.

    Read more about our acquisitions


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