• Frugal Propulsion – Principles and Practice!

    Frugal Propulsion – Principles and Practice!

    Our main product, Frugal Propulsion, focuses on turning data directly into actual, tangible fuel savings. That, in turn, translates into just as significant savings on CO2 emissions. On top of that, the data we collect is made available for integration into existing business intelligence solutions – or directly via our own web interface. This document covers the core data analysis principles we use, the product’s practical use, and how it differs from conventional propulsion control solutions.

    Frugal Propulsion Core Benefits

    What is in the package?

    A Frugal Propulsion package consists of three main components, two of which go onto the actual vessels:

    •The Frugal Propulsion HMI panel is basically an additional power handle that goes on the bridge.

    •An electronics cabinet that serves as the primary integration point for onboard sensors, the HMI panel, the existing propulsion control system, and our cloud calculation engine.

    The final part is the Cloud Calculation Engine (CCE) which accumulates all the data we collect on vessels with Frugal Propulsion. This engine does the actual calculations that result in the optimized propeller curves, which in turn save fuel. This part of the setup runs on secured servers that use banking encryption standards to ensure data is available only to us – and you.

    Built on top:

    Frugal Propulsion does not directly interface with propeller and engine but rather via the existing propulsion control system (PCS). We have established interfaces in cooperation with MAN Energy Solutions, Norisys GmbH, Wärtsilä Lyngsø, Kongsberg, and others at this point. We do this to ensure existing engine and propeller safety features remain in place, even when Frugal Propulsion is active. On top of that, we add additional safety mechanisms, such as a light running margin that is defined by engine health parameters to further safeguard all components involved. Our machine learning algorithms preen the data we use to generate propeller curves according to convex hulls that define allowable engine health parameters at varying engine RPMs and vessel conditions.

    Machine Learning:

    Frugal Propulsion is built in part upon the principles of Model Predictive Control, a well-established control principle in use in various forms in petrochemistry, robotics, and many other fields. The other main part of our cloud solution is modern machine learning which makes extracting tangible results from large amounts of data feasible. The core benefit of combining these methods is that it enables learning systems that benefit from experience instead of traditional regulation loops that only know about right now. In our case, we need to learn mainly about three different aspects of vessel propulsion:

    • Which areas of operation are the most efficient for the engine on a particular vessel? We want to figure out the optimal loading of the engine at discrete RPM values so we can establish a heat chart mapping the areas of operation we should aim for.

    • The next thing we need to know is how combinations of engine RPM and propeller pitch map to vessel speed and slip. We want to identify the combinations that provide the best specific fuel consumption (SFOC) across a range of RPM

    values, which makes up an optimal propeller curve.

    • Lastly, we need to map the relation between vessel condition and the optimal propeller curve. Vessel draft and trim significantly impact which combinations of RPM and pitch perform well concerning SFOC.

    Once we have established an optimal propeller curve, we can do several other things on top of that to save even more fuel. Frugal Propulsion also comes with two types of additional automation:

    • Speed pilot: By enabling the speed pilot, we can simply maintain the desired GPS speed by monitoring the actual speed and adjusting propulsion power according to the optimized propeller curve. This makes it much easier to ensure vessels do not consume too much fuel by ensuring speed is kept at the necessary level to meet scheduled arrival times.

    • Power pilot: Much like the speed pilot, using the desired power level as a setpoint ensures fuel consumption does not exceed a given value since the power output is directly proportional to fuel consumption.

    Our power pilot feature also enables us to ensure EEXI compliance simply by enforcing a power cap. Capping power also means capping speed, but by using our power pilot feature in conjunction with our continuously optimized propeller curve, at least you get as much speed as possible, using the power available. This is a simple and relatively easy way of ensuring EEXI compliance by 2023 while also ensuring a significant efficiency boost.

    Learning takes time:

    Figuring out which propulsion parameters are best while also being safe about it takes time. Our CCE needs several things to be able to calculate and deploy optimized propeller curves consistently:

    • The first thing we need is a set of initial data points to seed the CCE. We get these data by doing a sea trial on the vessel in question. During this trial, which typically takes about five hours, we systematically try out combinations of engine RPM and propeller pitch to positively identify the operational envelope – or to be exact: convex hull – of settings that make sense on this vessel. These collected values also serve as the basis for the initial propeller curve we deploy in the Frugal Propulsion set up during the trial.

    • The next thing is to make good use of the initial propeller curve to collect more data on these settings. After about a week or so of service, we generate the next propeller curve based on the initial curve and the data we have collected. The CCE will continue to deploy new curves while slowly exploring the effects of the increasing pitch at discrete RPM values to see if engine efficiency increases or decreases or if propeller slip is better or worse.

    • We also need reasonable conditions. Bad weather tends to inhibit the learning algorithm somewhat. It does its best to filter out noisy data that is influenced by waves, swells, or wind. But, if there are high winds or adverse conditions during extended periods, learning will take longer. We work hard to improve immunity to adverse conditions by including weather services, such as stormglass.io, into our CCE.

    Depending on the amount of use Frugal Propulsion sees, the process of uncovering the best propeller curve for a particular vessel condition may take from about a month to several. But as time progresses, the current propeller curve will come closer and closer to the optimal set of values. Doing things this way has several advantages:

    • Our continuously optimized propeller curves take vessel condition, equipment age, and several other variables into consideration in a way that a classical static combi curve simply cannot.

    • Unlike a classical regulation loop, our CCE can identify insufficient sensor data. Suppose a critical sensor such as the torque sensor or a fuel flow meter should fail. In that case, Frugal Propulsion will work just fine, using the latest propeller the CCE has made available – but new curves will not be generated until the sensor is fixed.

    • If necessary, we can compensate for equipment that might not perform entirely as it should, such as underperforming turbochargers. We do this simply by configuring the CCE according to whatever limits we agree upon with superintendents, chief engineers, and so on.

    • Unlike other pitch optimization solutions out there, we do not continuously change engine RPM and pitch to save fuel. Once the CCE has deployed a propeller curve, it only changes if a better one becomes available – typically no more than once per 24 hours. This, in turn, means we make no unnecessary wear-inducing adjustments to RPM and pitch.

    • Since the entire Frugal Propulsion system

    is an on-top solution, any critical errors that might occur, such as cable breaks or interface failures, simply reassigns remote control to the existing PCS until the error is fixed.

    Going further…

    Frugal Propulsion is much like an additional power handle that always knows about the best propulsion settings, but it is also a platform for deploying more features. Our initial product did not have a speed or power pilot, but it does now – with no changes to the underlying hardware. At this point, we are also looking into trim optimization. Once we have that feature in place, we will deploy it on vessels with Frugal Propulsion. The same goes for the products we make from the data we collect – as we go along, these features will become available to you. This is, in fact, the core of Frugal Propulsion – making the most of the things you already have.

  • IMO Adopts Measures To Reduce Ships’ Carbon Intensity

    IMO Adopts Measures To Reduce Ships’ Carbon Intensity

    Source: International Maritime Organization (IMO)- MediaCentre on 17 June 2021

    New mandatory measures to cut the carbon intensity of international shipping have been adopted by the International Maritime Organization (IMO), setting shipping on a course to meet greenhouse gas reduction targets established in the 2018 Initial IMO Strategy for Reducing GHG Emissions from Ships.

    IMO’s Marine Environment Protection Committee (MEPC 76), meeting in a remote session from 10 to 17 June 2021, adopted amendments to the International Convention for the Prevention of Pollution from Ships (MARPOL) Annex VI that will require ships to reduce their greenhouse gas emissions. These amendments combine technical and operational approaches to improve the energy efficiency of ships, also providing important building blocks for future GHG reduction measures.

    The new measures will require all ships to calculate their Energy Efficiency Existing Ship Index (EEXI) following technical means to improve their energy efficiency and to establish their annual operational carbon intensity indicator (CII) and CII rating. Carbon intensity links the GHG emissions to the amount of cargo carried over distance travelled.

    Ships will get a rating of their energy efficiency (A, B, C, D, E – where A is the best). Administrations, port authorities and other stakeholders as appropriate, are encouraged to provide incentives to ships rated as A or B also sending out a strong signal to the market and financial sector.

    A ship rated D for three consecutive years, or E, is required to submit a corrective action plan, to show how the required index (C or above) would be achieved.

    IMO Secretary-General Kitack Lim said the adoption of the new measures would build on IMO’s previously adopted mandatory energy efficiency measures, to lead shipping on the right path towards decarbonization.

    “The path to decarbonization is a long, but also a common path in which we need to consider and respect each other’s views. We have made a considerable amount of progress since the start of our journey,” Mr. Lim said, ” … your progress will continue to provide the benefit of experience to be able to make ambitious, and evidence-based decisions for phase 3 of the implementation of the operational measure which will be further strengthened and developed taking into account the review of the short-term measure and the latest climate science,” he added.

    The amendments to MARPOL Annex VI (adopted in a consolidated revised Annex VI) are expected to enter into force on 1 November 2022, with the requirements for EEXI and CII certification coming into effect from 1 January 2023. This means that the first annual reporting will be completed in 2023, with the first rating given in 2024.

    A review clause requires the IMO to review the effectiveness of the implementation of the CII and EEXI requirements, by 1 January 2026 at the latest, and, if necessary, develop and adopt further amendments. 

    Impact assessment

    In adopting the measure, MEPC also considered the outcomes of a comprehensive impact assessment of the measure which examined potential negative impacts on States, and agreed to keep the impacts on States of the measure under review so that any necessary adjustments can be made.

    In adopting the amendments, the MEPC agreed in its resolution to undertake a lessons-learned exercise from the comprehensive impact assessment of the amendments to MARPOL Annex VI, with a view to improving the procedure for conducting future impact assessments.

    Secretary-General Lim welcomed the approval and consideration of the outcome of the related comprehensive impact assessment and the decision to keep impacts of the measure under review and to initiate a lessons-learned exercise.

    MARPOL Annex VI has 100 Contracting States, who between them represent 96.65% of world merchant shipping by tonnage.

    The MEPC also adopted a work plan to develop mid-and long-term measures to further cut shipping’s GHG emissions, in line with the Initial IMO Strategy on reduction of GHG from ships

    Guidelines adopted

    Alongside the MARPOL amendments, the MEPC adopted related guidelines to support the implementation of the amendments.  (full list below).

    The guidelines include the 2021 Guidelines on the operational carbon intensity reduction factors relative to reference lines (CII Reduction factor Guidelines, G3). This includes the required reduction (Z) factor, which is set at a rate, relative to 2019, of 11% by 2026. This would  be further strengthened after that date, taking into account the review of the measure and latest climate science.

    Meeting the initial GHG strategy ambition

    The combined technical and operational measures referred to as short-term carbon intensity measures, are in line with the ambition of the Initial IMO GHG Strategy, which aims to reduce the carbon intensity of international shipping by 40% by 2030, compared to 2008.

    The initial strategy sets out short- mid-and long-term measures. The measures just adopted fall into the short-term measures.

    Future work

    The MEPC discussed a number of submissions on how to progress the next stages of IMO’s work to cut GHG emissions from ships, leading to the revision of the initial GHG strategy in 2023.

    The MEPC adopted a work plan on the concrete way forward to make progress with candidate mid-and long-term measures including measures to incentivize the move away from fossil fuels to low- and zero-carbon fuels to achieve decarbonization of international shipping.

    A proposal initially considered by MEPC suggested a mandatory levy of $100 per tonne carbon dioxide equivalent on heavy fuel oil. This proposal will be further considered at the inter-sessional working group meeting in the context of the adopted work plan along with other proposals for mid-term measures.

    The work plan envisages three phases:

    •Phase I – Collation and initial consideration of proposals for measures (Spring 2021 to spring 2022);

    •Phase II – Assessment and selection of measures(s) to further develop (Spring 2022 to spring 2023); and

    •Phase III – Development of(a) measure(s) to be finalized within (an) agreed target date(s).

    Mr. Lim welcomed the adoption of the work plan.

    “Concessions have been made on all sides in the interest of securing the framework we have in place. Our consideration of mid-and long-term measures will demand even more of us. I am very pleased that the Committee has agreed on a work plan to support carrying out this dimension of our work in a structured way that will keep the membership together,” Mr. Lim said.

    “Agreement on the work plan sends the signal that the Organization and its Member States are ready to further consider the current and future proposals for mid-term measures. We need to gear up work relating to the various phases of the work plan in order to give efficient and adequate consideration to concrete proposals for the reduction of greenhouse gases in keeping with our goals in the initial strategy.  Let us continue to work together on the tasks you have in front of you as we continue to make progress on this common path,” he said.

    IMRB proposal

    The Committee had a non-exhaustive consideration of a proposal to establish an International Maritime Research Board, funded by a tax on oil fuel used by shipping. The discussion will resume at the Committee’s next session.

    Correspondence Group and Intersessional Working Group

    The MEPC approved the terms of reference for a Correspondence Group on Carbon Intensity Reduction and meetings of the Intersessional Working Group on Reduction of GHG Emissions from Ships (ISWG-GHG 9 and ISWG-GHG 10). The ISWG-GHG 9 will meet 15-22 September and ISWG-GHG 10 18-22 October 2021, ahead of MEPC 77, which is scheduled to meet 22-26 November 2021.

    MEPC 76 – other outcomes

    The MEPC also adopted other amendments.

    Prohibiting HFO in the Arctic

    The MEPC adopted amendments to MARPOL Annex I (addition of a new regulation 43A) to introduce a prohibition on the use and carriage for use as the fuel of heavy fuel oil (HFO) by ships in Arctic waters on and after 1 July 2024.

    The prohibition will cover the use and carriage for use as the fuel of oils having a density at 15°C higher than 900 kg/m3 or a kinematic viscosity at 50°C higher than 180 mm2/s. Ships engaged in securing the safety of ships, or in search and rescue operations, and ships dedicated to oil spill preparedness and the response would be exempted. Ships that meet certain construction standards with regard to oil fuel tank protection would need to comply on and after 1 July 2029.

    A Party to MARPOL with a coastline bordering Arctic waters may temporarily waive the requirements for ships flying its flag while operating in waters subject to that Party’s sovereignty or jurisdiction, up to 1 July 2029.

    The amendments were approved at MEPC 75, see https://www.imo.org/en/MediaCentre/MeetingSummaries/Pages/MEPC-75th-session.aspx.

    Amendments to MARPOL Annexes I and IV concerning the exemption of UNSP barges from survey and certification requirements

    The MEPC adopted amendments to  MARPOL Annexes I and IV concerning the exemption of UNSP barges from survey and certification requirements.

    The amendment specifies that the Administration may exempt a UNSP barge from the annual survey and certification requirements, for a period not exceeding 5 years provided that the UNSP barge has undergone a survey to confirm that certain conditions are met.

    The amendments also provide the form for the International Oil Pollution Exemption Certificate for Unmanned Non-self-propelled Barges. The MEPC also approved a related circular on guidelines for exemption of UNSP barges.

    The amendments were approved at MEPC 75, see https://www.imo.org/en/MediaCentre/MeetingSummaries/Pages/MEPC-75th-session.aspx.

    Amendments to AFS Convention – cybutrene

    The MEPC adopted amendments to the IMO Convention for the Control of Harmful Anti-fouling Systems on Ships (AFS Convention), to include controls on the biocide cybutryne.

    The AFS Convention already prohibits the use of biocides using organotin compounds.

    The draft amendments were approved at MEPC 75, see https://www.imo.org/en/MediaCentre/MeetingSummaries/Pages/MEPC-75th-session.aspx.

    Further information

    Carbon intensity measures in detail

    The short-term measure is aimed at meeting the target set in the IMO Initial GHG Strategy – to reduce carbon intensity of all ships by 40% by 2030, compared to 2008. These will be mandatory measures under MARPOL Annex VI. They will bring in

    •Attained Energy Efficiency Existing Ship Index (EEXI) is required to be calculated for ships of 400 gt and above, in accordance with the different values set for ship types and size categories. This indicates the energy efficiency of the ship compared to a baseline. Ships are required to meet a specific required Energy Efficiency Existing Ship Index (EEXI), which is based on a required reduction factor (expressed as a percentage relative to the EEDI baseline).

    •Annual operational carbon intensity indicator (CII) and CII rating.

    The CII determines the annual reduction factor needed to ensure continuous improvement of the ship’s operational carbon intensity within a specific rating level.  The actual annual operational CII achieved (attained annual operational CII) would be required to be documented and verified against the required annual operational CII.

    This would enable the operational carbon intensity rating to be determined.  The rating would be given on a scale – operational carbon intensity rating A, B, C, D or E – indicating a major superior, minor superior, moderate, minor inferior, or inferior performance level. The performance level would be recorded in the ship’s Ship Energy Efficiency Management Plan (SEEMP).

    A ship rated D for three consecutive years, or E, would have to submit a corrective action plan, to show how the required index (C or above) would be achieved.

    Administrations, port authorities and other stakeholders as appropriate, are encouraged to provide incentives to ships rated as A or B.

    In simple terms, the short-term term measure are aimed at achieving the carbon intensity reduction aims of the IMO initial GHG Strategy.

    They do this by requiring all ships to calculate their Energy Efficiency Existing Ship Index (EEXI) and to establish their annual operational carbon intensity indicator (CII) and CII rating

    In other words, ships get a rating of their energy efficiency (A, B, C, D, E – where A is the best). A ship running on a low carbon fuel clearly gets a higher rating than one running on fossil fuel.

    However, there are many things a ship can do to improve its rating through various measures, such as hull cleaning to reduce drag; speed and routing optimization; installation of low energy light bulbs; installation of solar/wind auxiliary power for accommodation services; etc.


    The following comprehensive set of guidelines, adopted by MEPC 76, support the new requirements:

    •2021 Guidelines on the method of calculation of the attained energy efficiency existing ship index (EEXI);

    •2021 Guidelines on survey and certification of the energy efficiency existing ship index (EEXI);

    •2021 Guidelines on the shaft/engine power limitation system to comply with the EEXI requirements and use of a power reserve;

    •2021 Guidelines on operational carbon intensity indicators and the calculation methods (CII Guidelines, G1);

    •2021 Guidelines on the reference lines for use with operational Carbon Intensity Indicators (CII reference lines guidelines, G2);

    •2021 Guidelines on the operational carbon intensity reduction factors relative to reference lines (CII Reduction factor Guidelines, G3);

    •2021 Guidelines on the operational Carbon Intensity rating of ships (CII rating guidelines, G4).

  • EEXI and CII- The Factual and Contractual Considerations!

    EEXI and CII- The Factual and Contractual  Considerations!

    Despite the fact that January 2023 may appear to be a long way off, shipowners and operators must evaluate the impact of the Energy Efficiency Existing Ship Index and the Carbon Intensity Index.


    For centuries, ships and vessels have been used to move cargo, beginning with self-propelled craft and progressing to sailing ships that harness the power of the wind to propel the vessel. Of course, such modes of transportation have a negligible carbon footprint. Steam-powered ships eventually replaced sailing vessels, giving rise to today’s commercial fleets powered by fuel oil, diesel oil, and, in some instances, LNG. The shipping sector aims to go full circle, at least in terms of minimizing carbon emissions, while also looking for inventive ways to retain efficiency, as the vital issues of climate change and ensuring a low carbon footprint rightfully come to the fore.

    EEXI – The Energy Efficiency Existing Ship Index

    EEXI – The Energy Efficiency Existing Ship Index is the latest measure to decarbonize shipping, focusing on greenhouse emissions rather than sulphur. The International Maritime Organization (IMO’s) suggests creating a minimum efficiency requirement for current ships based on design parameters. The Energy Efficiency Design Index (EEDI) is a variation of the EEXI that applies to new ships built after 2013. The EEXI is based on CO2 emissions per tonne mile, with the vessel’s installed power and cargo-carrying capacity being the essential components in its computation. When that goes into effect in January 2023, the EEXI will be a one-time ‘pass or fail’ paperwork test conducted at the first annual or special survey and will impact more than half of the world fleet.

    Carbon Intensity Index (CII)

    Whereas the EEXI is a one-time certification that focuses on design specifications, the Carbon Intensity Index (CII) is an annual examination of a ship’s actual carbon emission performance over the previous year, beginning in January 2023. It measures how effectively a ship delivers products or passengers in terms of grams of CO2 emitted per cargo-carrying capacity and nautical miles.

    CII compliance will necessitate extensive planning to develop technical and operational solutions to improve vessel emissions performance. Noncompliance and/or low ratings are unlikely to have severe consequences until 2026, but it will be interesting to observe whether, in addition to remedial action, the market will generate its own practical sanctions in the longer future.


    The proposed adjustments will affect all ships built before 2010, which burn significantly more fuel than current designs. They will also affect 60-70 percent of bulk carriers, primarily those larger than Panamax, and a considerable percentage of tankers, primarily those larger than Aframax, as well as LNG carriers and 250 steam turbine ships around the world. Slow-steaming, weather routing, optimized port rotation, cargo intake reduction, and the use of alternative fuels such as biofuels and LNG are just a few of the methods owners can use to cut CO2 emissions.

    Contractual and Factual Considerations

    With the introduction of the EEXI and CII fast approaching, owners and operators should consider the legal issues that may arise. Any first adjustments to satisfy EEXI criteria will almost certainly fall on the shipowner, who must comply with MARPOL and will certainly have contractual duties to ensure compliance with the convention and its regulations under charter parties. Owners and charterers will have to carefully assess their alternatives for time charters that run after 2023 and beyond. Shipowners, for example, may need to make sure that stipulations in their draught contracts allow them to address all technical issues emerging from the new IMO decarbonization obligations imposed by EEXI and CII. Owners may wish to make sure that they have the freedom to upgrade their vessels with new technologies before the new restrictions take effect in January 2023 or that they can take corrective action after that date. Owners may, for example, desire the ability to arrange for dry-docking the vessel during the charter for modifications or an additional dry-dock, so temporarily removing the ship from the charterers’ service without violating the charter.


    Like it always does, the shipping sector will adjust to the significant new legislation aimed at reducing carbon emissions, and it is hoped that boats can be operated efficiently in the future from both an environmental and commercial standpoint. Owners and charterers will, as always with the introduction of new legislation, need to carefully evaluate the commercial, legal, and contractual position between themselves in advance to prevent potential problems when the new restrictions take effect.

    Contact Frugal to know more about solutions that will help you to comply with these new regulations and make your Sea Journey a non-stoppable voyage.