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Engine part-load optimization

Tune up for environmental compliance and enhanced efficiency

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The Energy Efficiency Design Index for Existing Ships (EEXI) will make limiting engine power a key ingredient in reducing greenhouse gas (GHG) emissions. ABB Turbocharging’s engineering experience, deep understanding of engine performance and expertise across engine designs makes us the ideal one-stop shop for your engine optimization.

Following draft new mandatory measures by International Maritime Organization (IMO) or outcome from conventions like the MARPOL Annex VI (as well as upcoming regulations in MEPC 76 (Marine Environment Protection Committee) like ISWG GHG 7-2-7) , many vessels will need to limit engine power – rather than simply sailing slowly to reduce fuel consumption - to meet new design efficiency requirements imposed by EEXI. Whether slow steaming to improve operational efficiency or complying with design efficiency regulations, engine optimization is an important part of a compliant and cost-effective vessel.

Learn more about how ABB can help you adapt to emerging compliance requirements

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  • NOx emission: 10-20% NOx reduction

  • SFOC: 3-5 g/kWh savings

  • Reliability: improved at part load (eg, smoke, deposits, piston running)


  • Rating can be adapted - eg, for new higher-efficiency propellers and lower loads

  • Applicable on majority of engine types

  • When reduction of NOx is target


  • SFOC: 6-10 g/kWh savings

  • Reliability: improved at part load (eg, smoke, deposits, piston running)

  • Simplified IMO certification process


  • Limited to engine types with two or more turbochargers

  • Permanent blinding or flexible cut-out

  • Can be applied in case of power restriction (eg, new propeller for reduced speed
    and power)


  • NOx emission: same weighted average

  • SFOC: 3-5 g/kWh savings

  • Reliability: improved at part load (eg, smoke, deposits, piston running)

Applications and scope

  • Can be applied on almost all engine types

  • Exhaust bypass pipes, valve, controller,
    and new turbo parts to be installed


Benefits of different options

ABB can help all the way

There are many ways of ensuring optimal performance while limiting engine power. These range from permanent engine derating to wastegate installations that retain the option of high-load operation, or simply re-matching turbochargers to lower engine loads. ABB’s Tekomar engine experts will investigate options based on your current engine specification, expected future load pattern and regulatory requirements, delivering solutions with highly competitive payback periods , meeting upcoming CII (Carbon Intensity Indicator) ratings or as a part of your SEEMP (Ship Energy Efficiency Management Plan). See our recent case study here

ABB can lead you through the entire project, from finding the right solution to final engineering, including managing IMO NOx certification and invitation of the class for the approval of the final EEXI technical file. Our complete project management and engineering solution means that you only need one partner to ensure your engines remain efficient and compliant.

 Typical scope for engine part-load optimization:

  • Basic engineering for applicable solutions

  • Consulting in finding the right package for your needs

  • Detail engineering consisting:

    • Specification of engine parts required for tuning

    • Specification of turbocharger parts required for tuning

    • Preparing of IMO NOx technical file

    • Consulting during re-certification

  • Supervision of engine works

  • Delivery and execution of re-matching of turbocharger

  • Execution of confirmation trial and fine tuning

  • Witness of IMO NOx measurement*

  • Final report including IMO NOx file* or amendment to IMO NOx technical file

 * for parent engine only

See an example of a successful engine part-load optimization project Link to Odfjell article.

Send us an enquiry


Contact us with an e-mail to discuss your current and future requirements, and we can provide a tailor-made upgrade project to fit your exact business needs.

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