Revolutionary Ammonia-Powered Engine by MAN B&W Paves the Way for Sustainable Shipping

Author: Daniel G. Teleoaca – Marine Chief Engineer

MAN Energy Solutions (MAN ES) has announced a breakthrough in its research and development of a two-stroke engine that can run on ammonia, a carbon-free and sulphur-free fuel. The company successfully completed the first test of its MAN B&W engine operating on ammonia at its Research Center Copenhagen (RCC) in July 2023.

Ammonia is considered one of the most promising candidates for the future of green shipping, as it can be produced from renewable energy sources and does not emit any greenhouse gases or air pollutants when burned in an engine. According to the International Maritime Organization (IMO), maritime shipping is responsible for around 2.5 percent of global greenhouse gas emissions and needs to reduce them by 70 percent by 2050.

Source and credit:

MAN ES started working on a B&W two-stroke engine operating on ammonia back in 2019 with a pre-study of the fuel supply and injection concept combined with several hazard and hazard and operability studies (hazid/hazop) together with classification societies, shipowners, yards, and system suppliers. The following year, a second test engine arrived in Copenhagen, enabling a parallel-test engine setup with different fuels at RCC.

The first test of the ammonia engine was conducted on a 50 percent load at RCC’s testbed no. 5, which is equipped with a newly developed ammonia injection system and a newly designed combustion chamber. The test showed that the engine can run stably and efficiently on ammonia with low NOx emissions. The test also demonstrated that the engine can switch seamlessly between ammonia and conventional fuels such as diesel or liquefied natural gas (LNG).

Brian Østergaard Sørensen, Head of Two-Stroke Research and Development at MAN ES, said: “This is obviously an ambitious undertaking, but we can meet it. The industry is already on board and working intensively with us towards greener maritime shipping.” He added that the company aims to have a commercially available two-stroke ammonia engine by as early as 2024, followed by a retrofit package for the gradual rebuild of existing maritime vessels by 2025.

The development of the ammonia engine is part of MAN ES’s strategy to offer a fuel-flexible portfolio of two-stroke engines that can run on almost any fuel or fuel quality. The company has already developed engines that can run on methanol, ethanol, liquefied petroleum gas (LPG), and hydrogen. The final goal for two-stroke engines is to run them entirely on carbon-neutral and carbon-free fuels.


Sewage Air Blower: A Vital Component Onboard – Operation, Maintenance, and Troubleshooting

Onboard marine vessels, sewage treatment is a critical aspect of environmental responsibility and operational efficiency. One key component that plays a significant role in this process is the sewage air blower.


Example of sewage air blower

This article will delve into the correct operation, maintenance, and troubleshooting of sewage air blowers, emphasizing their importance and the role of onboard marine engineers.

The Importance of Sewage Air Blowers

Sewage air blowers are essential for aerating wastewater in sewage treatment systems. They provide the necessary oxygen for the aerobic bacteria to break down organic matter, ensuring the effluent is treated effectively. Properly functioning sewage air blowers are crucial for adhering to environmental regulations, reducing environmental impact, and maintaining the overall well-being of the marine environment.

Example of air blower installed on sewage treatment plant

The following are some guidelines for the correct operation, maintenance, and troubleshooting of sewage air blowers.


Source and Credit: Victor Marine Ltd.

  • Start-Up Procedure: The correct operation of sewage air blowers begins with a well-defined start-up procedure. Marine engineers should ensure that the blower is started and stopped following the manufacturer’s recommendations.
    • The blower should be started before the sewage treatment plant is put into operation.
    • This usually involves gradually increasing air pressure and monitoring various parameters.
    • The blower should be kept clean and free from any obstructions.
    • The blower should be stopped only after the sewage treatment plant has been shut down.
  • Airflow Control: Maintaining the right airflow is vital. Marine engineers must adjust the blower’s speed and air pressure to ensure that oxygen levels in the sewage treatment tanks remain within the optimal range for microbial digestion.
  • Monitoring and Data Collection: Continuous monitoring of air blower performance is crucial. Modern vessels are equipped with monitoring systems that record essential data, enabling engineers to detect issues early. Regularly analyzing this data can help prevent problems before they escalate.


Source and Credit: Sean Lentze

  • Scheduled Inspections: Regular inspections are the cornerstone of maintenance. Marine engineers should follow a well-defined inspection schedule, checking for leaks, blockages, or any signs of wear and tear.
  • Lubrication: Ensure proper lubrication of the blower’s moving parts according to the manufacturer’s recommendations. Lubrication helps reduce friction, heat, and wear, extending the blower’s lifespan.
  • Air Filter Maintenance: The air filter is essential for keeping the blower’s intake air clean. Regularly clean or replace air filters as needed to prevent blockages and maintain airflow efficiency.
  • Impeller blades condition: Check the shape and condition of the blower impeller blades. Repair or replace as found necessary.


  • Unusual Noises: If unusual noises emanate from the blower, it’s an indication of potential issues, like worn-out bearings or a damaged impeller. Investigate the source of the noise and address it promptly.
  • Reduced Airflow: A drop in airflow could signify blockages, damaged components, or issues with the blower itself. If the blower is not providing enough air, it could be due to a clogged filter or a worn-out V-belt. Marine engineers should identify and rectify the problem to restore normal operation.
  • Vibration: Excessive vibration can cause damage to the blower and its mounting. Balancing and aligning the blower can resolve this issue.
  • Temperature Fluctuations: Sudden temperature changes may indicate a malfunctioning blower. Marine engineers should investigate and repair the blower or its associated systems to maintain stable operation.

The Role of Onboard Marine Engineers

Onboard marine engineers play a pivotal role in ensuring the correct operation, maintenance, and troubleshooting of sewage air blowers. Their responsibilities encompass routine checks, preventive maintenance, and immediate response to issues. Engineers should work closely with manufacturers to understand the specific requirements of the blower installed on the vessel and have the necessary tools and spare parts readily available.

It is important to note that proper operation and maintenance of sewage air blowers are critical to ensure that the sewage treatment plant functions efficiently. 

In conclusion, sewage air blowers are integral to the proper functioning of sewage treatment systems on marine vessels. Their correct operation, maintenance, and troubleshooting are essential for environmental compliance and overall operational efficiency. Onboard marine engineers hold the key to the effective and reliable performance of sewage air blowers, and their diligence in these aspects is paramount to safe and eco-friendly maritime operations.

If you have any questions regarding above, please feel free to use our existing forum Seafarer’s World, Telegram Chief Engineer’s Log Chat or Instagram and will try to answer to all your queries. You can use the feedback button as well!

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Europe Takes a Bold Step Towards a Greener Future: Freon Gas Phase-Out Looms

Author: Daniel G. Teleoaca – Marine Chief Engineer

In a resolute move towards a more sustainable future, Europe is set to embark on a journey to phase out the use of Freon gas, a potent greenhouse gas responsible for depleting the ozone layer. The impending interdiction has far-reaching implications, both environmentally and economically, and its impact on industries such as the maritime sector is a significant focal point. This landmark decision seeks to address climate change concerns, reduce environmental damage, and promote the adoption of eco-friendly alternatives.

Source and Credit:

The European Union (EU) has adopted a regulation that aims to phase out the use and emissions of fluorinated gases (F-gases), a type of refrigerant that has a high global warming potential (GWP) and contributes to climate change. The regulation will affect the refrigeration and air-conditioning industry, as well as the maritime industry, which relies heavily on F-gases for cooling and temperature control.

F-gases are widely used in various cooling and air-conditioning applications, such as refrigerators, freezers, chillers, heat pumps, air conditioners, or provisional cooling systems. However, F-gases have a high GWP, which means that they trap more heat in the atmosphere than carbon dioxide (CO2) when released. According to the European Commission, F-gases account for about 2% of the EU’s greenhouse gas emissions, and their use is expected to increase by 50% by 2030 without further action.

To address this issue, the EU has adopted the F-gas Regulation (517/2014), which aims to reduce the use and emissions of F-gases by 79% by 2030, compared to the average level in 2009-2012. The regulation imposes a gradual phase-down of F-gas production and import quotas, as well as a service ban on certain F-gases with a GWP of 2,500 or more from 1 January 2020. The regulation applies to all EU countries and EU-flagged vessels.

Source and Credit:

The F-gas regulation has important implications for the refrigeration and air-conditioning industry, as well as for consumers and end-users of F-gas products. The phase-down of F-gas quotas means that the supply and availability of high-GWP F-gases will decrease over time, and their prices will increase accordingly. This creates an incentive for manufacturers and users to switch to alternative refrigerants with lower GWP and higher energy efficiency.

The service ban on high-GWP F-gases means that from 1 January 2020, new or virgin F-gases with a GWP of 2,500 or more cannot be used to service or maintain refrigeration equipment with a charge size of 40 tonnes of CO2 equivalent or more. This applies to both new and existing systems, except for those with a charge size below the threshold. This means that users of such systems will have to either replace them with new ones that use alternative refrigerants, or use reclaimed or recycled F-gases that meet certain quality standards.

The F-gas regulation also imposes other mandatory requirements, such as checking and repairing of leakage, proper labeling of products and equipment, training and certification of personnel, reporting of data, and recovery and destruction of F-gases at the end of their life cycle. These requirements aim to prevent and reduce the emissions of F-gases throughout their life cycle.

The maritime industry is particularly affected by the F-gas regulation, as almost all vessels have refrigeration systems on board that use F-gases for chilling, freezing, air conditioning, provisional cooling, or temperature control inside cargo holds. According to a report by IMO in 2014, more than 90% of all merchant fleet use HCFC/HFC as their primary refrigerant. Therefore, ship owners and operators need to be aware of their obligations under the F-gas regulation and take appropriate actions to comply with it.

The transition from F-gases to alternative refrigerants may pose some challenges and risks for the maritime industry. For example:

  • The alternative refrigerants that are available or emerging in the market have different properties and characteristics than F-gases, such as flammability, toxicity, pressure, or compatibility with existing equipment. This means that they may require different design, installation, operation, maintenance, and safety measures than F-gases. Therefore, ship owners and operators need to carefully assess the suitability, performance, cost-effectiveness, and environmental impact of each alternative refrigerant for their specific application before making a switch.
  • The transition from F-gases to alternative refrigerants may also entail significant technical, financial, regulatory, and logistical challenges for ship owners and operators. For example, they may need to invest in new equipment or retrofit existing ones; comply with different standards or regulations in different countries or regions; ensure adequate supply chain management and availability of alternative refrigerants; train or certify their personnel; or deal with potential legal liabilities or insurance issues.

The European Commission provides guidance and support for the implementation of the F-gas regulation through various channels. For example:

  • The Commission publishes regular reports on the progress and impact of the F-gas regulation.
  • The Commission maintains a website that provides information and resources on the F-gas regulation, such as FAQs, guidance documents, best practices, case studies, or webinars.
  • The Commission organizes workshops and events to raise awareness and facilitate dialogue among stakeholders on the F-gas regulation.
  • The Commission funds research and innovation projects that aim to develop and demonstrate alternative refrigerants and technologies for the refrigeration and air-conditioning industry.

The F-gas regulation is a key instrument for reducing greenhouse gas emissions and mitigating climate change in the EU. It also provides an opportunity for the refrigeration and air-conditioning industry to innovate and adopt more sustainable and efficient solutions. However, the regulation also entails some challenges and risks for the stakeholders involved, especially for the maritime industry. Therefore, it is important for them to be well-informed and prepared for the transition from F-gases to alternative refrigerants. The maritime industry, a vital component of the European economy, will need to adapt to these changes, ensuring compliance with regulations and embracing eco-friendly refrigeration systems to contribute to a healthier planet for future generations.


Source and Credit:

Centrifugal Pump Casing Repair Onboard Vessels: A Comprehensive Guide

Centrifugal pumps are critical components on board vessels, responsible for various fluid-handling tasks such as cooling, ballasting, and transferring liquids. They are simple and reliable machines that operate on the principle of converting mechanical energy to kinetic energy and then to pressure energy.

However, like any other machinery, they are subject to wear and tear and may require maintenance and repair from time to time. One of the common problems that affect centrifugal pumps is the damage or erosion of the pump casing.

Example of centrifugal pump casing

The pump casing is the stationary part of the pump that encloses the impeller and directs the flow of the fluid. It also converts the kinetic energy of the fluid to pressure energy. The pump casing can be damaged by various factors, such as corrosion, cavitation, abrasion, erosion, fatigue, or impact. These factors can cause cracks, holes, dents, or thinning of the casing wall, which can reduce the efficiency and performance of the pump and lead to leakage, vibration, noise, or even failure.

To mitigate these risks, it’s essential for maritime professionals to understand the process of centrifugal pump casing repair and its feasibility onboard vessels. In this comprehensive guide, we will explore whether it is possible to conduct centrifugal pump casing repair onboard, the equipment and materials required, the skills needed from the crew, and the operational precautions to take after the repair.

Is Onboard Centrifugal Pump Casing Repair Feasible?

Repairing centrifugal pump casings onboard vessels is not only possible but often necessary to maintain the vessel’s operational efficiency and safety.

Repairing the pump casing is an important task that should be done as soon as possible to prevent further deterioration and ensure the safety and reliability of the pump. Repairing the pump casing onboard vessels can be challenging due to the limited space, resources, and time available. Therefore, it is essential to have a proper plan and procedure for carrying out this task effectively and efficiently.

However, it’s important to assess the extent of the damage before deciding whether a repair can be carried out at sea or if the pump should be taken to a shore-based facility for more extensive repairs.

Feasibility Factors:

  • Extent of Damage: Minor casing damage, such as small cracks or corrosion, can typically be repaired onboard. Extensive damage may require specialized equipment and expertise available ashore.

  • Availability of Equipment and Materials: Vessels need to be equipped with the necessary tools and materials to perform casing repairs effectively. Having a well-stocked spare parts inventory is crucial.

  • Crew Skills: The onboard crew should have the required knowledge and skills to perform casing repairs safely and effectively.

  • Operational Considerations: It’s essential to consider the vessel’s operational needs and downtime constraints when deciding whether to repair the casing onboard.

How to Repair a Centrifugal Pump Casing Onboard

Repairing a centrifugal pump casing onboard a vessel involves a series of steps and requires specific equipment and materials:

  • Safety Precautions: Before starting any repair work, ensure the pump is shut down, and the associated systems are depressurized to prevent accidents. Isolate the pump from the system by closing the suction and discharge valves and locking them with chains. Switch off and lock the electrical supply to the pump and attach a warning notice. Drain the pump by opening the drain valves and cracking open the flange joints carefully.

  • Pump removal: Remove the pump from its location by using a chain block or a crane and place it on a suitable workbench or platform. Remove any external fittings or accessories that may interfere with the repair work.

  • Pump dismantling: Dismantle the pump by following the manufacturer’s instructions or using a general procedure. Remove the impeller, shaft, bearings, seals, sleeves, rings, etc. from the casing and inspect them for any damage or wear. Clean them thoroughly and store them safely for reassembly.

    Example of centrifugal pump sectional view after dismantling

  • Inspection: Carefully inspect the casing to assess the damage’s extent and location. Common issues include cracks, corrosion, and erosion. Measure the thickness of the casing wall using a caliper or a thickness gauge, if available, and compare it with the original specifications or acceptable limits. Mark the areas that need repair with a marker or a chalk.
  • Cleaning: Thoroughly clean the damaged area to remove any contaminants, rust, or debris. Proper cleaning ensures better adhesion of repair materials.

  • Choose a suitable repair method for the pump casing depending on the type and extent of damage, availability of materials and equipment, and skill level of crew members. The most common repair methods are welding, brazing, soldering, epoxy resin filling, metal spraying, or chrome plating. Each method has its own advantages and disadvantages in terms of cost, durability, quality, ease of application, etc. Therefore, it is important to weigh these factors carefully before selecting a repair method.
  • Preparation: If welding or brazing is chosen as a repair method, preheat the casing to a suitable temperature to avoid thermal stress or distortion. If epoxy resin or other repair material application is chosen, prepare the casing surface for repair by roughening it with abrasive tools. This helps enhance the bond between the casing and the repair material.

Materials and Equipment in case of epoxy resin:

    • Epoxy Resin: Use a high-quality epoxy resin suitable for marine applications.
    • Fiberglass Cloth: Employ fiberglass cloth or mat for reinforcement.
    • Putty Knife/Roller: These tools help apply and smooth the repair materials.
    • Safety Gear: Crew should wear appropriate protective gear, including gloves and eye protection.

Application of Epoxy Resin: Mix the epoxy resin according to the manufacturer’s instructions and apply it to the damaged area. Place fiberglass cloth over the resin and apply more resin to saturate the cloth fully.

Curing: Ensure that there are no gaps or air bubbles in the repair material and that it covers the damaged areas completely and evenly. Allow the repair to cure for the recommended time. This may vary based on the resin used and environmental conditions. Monitor temperature and humidity levels.

Sanding and Finishing: After curing, sand the repaired area to achieve a smooth finish. This may require multiple passes with progressively finer sandpaper.

Painting: Apply an appropriate marine-grade paint to protect the repaired area from corrosion and improve aesthetics.

Crew Skills Required for Onboard Repair

Performing a centrifugal pump casing repair onboard requires a skilled crew with the following expertise:

  • Mechanical Knowledge: Crew members should understand the pump’s operation, its components, and the function of the casing.

  • Composite Repair Skills: Familiarity with composite repair techniques, including surface preparation, resin application, and curing processes, is crucial.

  • Safety Awareness: Crew members must prioritize safety, including following safety procedures, wearing protective gear, and handling chemicals responsibly.

  • Problem Solving: The ability to assess damage, determine the appropriate repair method, and troubleshoot issues during the repair process is essential.

Operational Precautions After Repair

After completing the centrifugal pump casing repair onboard, it’s crucial to take specific operational precautions to ensure the pump’s continued functionality and vessel safety:

  • Testing: Conduct a comprehensive test of the pump to ensure it operates as expected. Monitor performance, pressure, and temperature closely during testing.

  • Regular Inspection: Implement a regular inspection and maintenance schedule to monitor the repaired casing and identify any signs of wear or damage.

  • Documentation: Maintain detailed records of the repair, including the materials used, repair date, and crew members involved, for future reference.

  • Training: Train crew members on the importance of proper pump operation and maintenance to prevent future issues.

In conclusion, centrifugal pump casing repair onboard vessels is feasible and often necessary to ensure the vessel’s smooth operation and safety. By following the proper procedures, having the necessary equipment and materials, and employing a skilled crew, maritime professionals can effectively repair pump casings at sea. It’s essential to prioritize safety, adhere to manufacturer guidelines, and implement regular maintenance to extend the life of the repaired pump casing and avoid costly breakdowns at sea.

If you have any questions regarding above, please feel free to use our existing forum Seafarer’s World, Telegram Chief Engineer’s Log Chat or Instagram and will try to answer to all your queries. You can use the feedback button as well!

If you like my posts, please don’t forget to press Like and Share. You can also Subscribe to this blog and you will be informed every time when a new article is published.

Also you can buy me a coffee by donating to this website, so I will have the fuel I need to keep producing great content! Thank you!

Revolutionary Hydrogen Generator Sets Sail: A New Era for Clean Energy on Vessels

Date: October 03, 2023

By: Daniel G. Teleoaca – Marine Chief Engineer

In a groundbreaking development, the maritime industry is on the brink of a transformation towards cleaner and more sustainable energy sources. The introduction of hydrogen generators for marine applications onboard vessels promises to revolutionize the way ships operate, reduce emissions, and usher in a new era of environmental responsibility.

Hydrogen, known as the most abundant element in the universe, has long been touted as a clean and efficient energy source. Recent advancements in hydrogen generation technology have paved the way for its adoption in various industries, including maritime. These developments are poised to significantly reduce the carbon footprint of vessels, helping the shipping industry make substantial progress towards achieving its sustainability goals.

Hydrogen is a promising alternative fuel for the maritime sector, as it can provide zero-emission power for various applications, such as main propulsion, electrical generation, and refrigeration. However, one of the main challenges of using hydrogen onboard vessels is the storage and delivery of compressed hydrogen, which requires high pressure, large volume, and complex infrastructure.

A novel solution to this challenge is to generate hydrogen onboard vessels using methanol and water as feedstocks. Methanol is a liquid fuel that can be easily stored and transported at ambient conditions, and water can be sourced from the sea. Methanol and water can be converted to hydrogen and carbon dioxide by a catalytic reforming process, which can then feed a proton exchange membrane (PEM) fuel cell to produce electricity and heat.

This technology has been developed by e1 Marine1, a company that specializes in hydrogen on-demand generators for the marine sector. e1 Marine’s M-Series hydrogen generator is a compact and mobile unit that can be installed directly onboard fuel cell vessels. The M-Series can produce up to 50 kg of hydrogen per day, enough to power a 200 kW fuel cell system. The M-Series uses methanol enriched with water, which has up to six times the energy density of compressed hydrogen, providing fuel cell power solutions with significantly reduced cost, increased safety, efficiency, and operational range.

Marine mobile hydrogen generator. Source and Credit: e1 Marine

e1 Marine’s M-Series hydrogen generator has been successfully tested and demonstrated on various vessels, such as inland and coastal ferries, research vessels, and container ships. e1 Marine has also partnered with Maritime Partners2, a leading provider of leasing and financing solutions for the maritime industry, to offer flexible leasing options for vessel operators who want to adopt clean technology for their fleets.

According to Dr. Dave Edlund, the CEO of e1 Marine, “Hydrogen is the ultimate clean fuel for the maritime sector, but it has been hindered by the challenges of storage and delivery. Our M-Series hydrogen generator solves these challenges by producing hydrogen onboard vessels using methanol and water as feedstocks. This technology enables vessel operators to reduce their carbon footprint and comply with the IMO 2030/50 regulations, while also saving on fuel costs and increasing their operational flexibility.”

e1 Marine’s M-Series hydrogen generator is one of the examples of how hydrogen fuel cells can be applied in maritime settings. Other examples include the Zero/V3, a hydrogen fuel-cell coastal research vessel designed by Sandia National Laboratories; the Energy Observer4, an experimental ship that uses renewable energy and seawater electrolysis to generate onboard hydrogen; and the Containerized Hydrogen Generator1, a modularized methanol/fuel cell power solution that can provide zero-emission shore power.

The adoption of hydrogen generators for marine use holds immense promise in reducing greenhouse gas emissions from the shipping industry. Currently responsible for a significant portion of global emissions, the maritime sector has been under increasing pressure to reduce its environmental impact.

Hydrogen generator for marine application onboard vessels is a clean and cost-effective solution that can help the maritime sector achieve its decarbonization goals and enhance its competitiveness in the global market.

Source and Credit:

  • e1Marine;
  • Sandia Energy; 

The Vital Role of Deck Air Vents on Vessels: Maintenance, Troubleshooting, and Safety

Deck air vents may not be the most prominent features on a ship, but they play a crucial role in ensuring the safety, efficiency, and environmental responsibility of seafaring operations. These unassuming openings serve as a means of maintaining the integrity of various tanks onboard vessels.

Source and credit: Captain Damley

Deck air vents are devices that allow the passage of air in and out of the tanks onboard vessels, such as cargo holds, ballast tanks, fuel tanks, and fresh water tanks. They are essential for maintaining the pressure balance, the quality of the cargo or fluid, and the safety of the vessel and crew. In this article, we will explain the purpose of fitting deck air vents for different tanks onboard vessel, the maintenance required and troubleshooting in case of malfunction, and the importance of their proper operation and the risk associated with their defects and malfunction.

The Purpose of Deck Air Vents

Deck air vents are strategically placed openings on the deck of a vessel, each serving a specific purpose for various onboard tanks. Their primary functions include:

  • Preventing Overpressure: One of the most critical roles of deck air vents is to prevent the overpressure of tanks. When a tank is loaded or unloaded, it undergoes changes in volume due to temperature fluctuations and the addition or removal of liquid cargo. Without proper venting, pressure imbalances can develop within the tank, leading to structural damage or even catastrophic failure. Deck air vents provide a controlled release of excess pressure to ensure the tank’s integrity.
  • Minimizing Vacuum Conditions: During the discharge of liquid cargo, especially in tanks like ballast or cargo tanks, a vacuum can form as the liquid is pumped out. This vacuum can potentially collapse the tank structure if not relieved. Deck air vents allow air to enter the tank, equalizing the pressure and preventing collapse.

  • Reducing Gas Buildup: Certain tanks, like fuel oil or sewage tanks, may produce gases or vapors that need to be vented to prevent the buildup of hazardous conditions or explosions. Deck air vents allow these gases to dissipate safely into the atmosphere.

  • Maintaining Tank Integrity: Proper ventilation helps to reduce the corrosion of tank internals caused by moisture accumulation. It also minimizes the risk of contamination, ensuring the quality and safety of stored liquids.

Maintenance and Inspection

To ensure the effectiveness of deck air vents, regular maintenance and inspections are essential. Here’s a checklist of maintenance tasks:

  • Clean and Clear Vents: Deck air vents should be cleaned periodically to remove any dirt, dust, salt, rust, or debris that may accumulate inside them. This can be done by using compressed air, water jets, brushes, or solvents. Cleaning should be done more frequently for cargo hold vents that handle dusty or dirty cargoes

  • Functional Valves: If equipped with pressure/vacuum relief valves, make sure they are in good working condition. Replace any malfunctioning valves promptly.

  • Leak Checks: Inspect for leaks around the vent openings. Leaking vents can compromise the tank’s integrity and should be repaired immediately. Deck air vents that are damaged, corroded, leaking, blocked, or malfunctioning should be repaired as soon as possible to restore their normal operation and prevent further deterioration. This can be done by replacing worn-out parts, welding cracks, sealing leaks, clearing obstructions, or adjusting settings. Repairing should be done by qualified personnel following the manufacturer’s instructions and safety precautions.

Example of damaged air vent

  • Corrosion Prevention: Apply appropriate anti-corrosion coatings to vent openings and surrounding areas to protect against corrosion. Deck air vents that have moving parts, such as valves, springs, hinges, or flaps, should be lubricated regularly to ensure smooth operation and prevent seizing or jamming. This can be done by using grease, oil, or spray lubricants. Lubricating should be done more frequently for deck air vents that are exposed to salt water spray or humid conditions.
  • Operational Testing: Deck air vents should be tested periodically to check their performance and functionality. Testing should be done more frequently for deck air vents that handle hazardous cargoes or fluids.

    Periodically test the pressure relief and vacuum-breaking functions of the vents to ensure they are functioning as designed.

Troubleshooting Malfunctions

When deck air vents malfunction, it can lead to severe consequences. Here’s how to troubleshoot common issues:

  • Blockages: If you suspect a blockage, inspect the vent for debris or obstructions.

    Example of damaged air vent

    Remove any foreign materials and clean the vent thoroughly.

  • Leakage: If you notice leaks, inspect the sealing gaskets and connections. Replace any damaged components and ensure a tight seal.

  • Inoperative Valves: If pressure relief or vacuum-breaking valves fail to operate, consult the manufacturer’s guidelines for maintenance or replacement instructions.

The Importance of Proper Operation

Deck air vents are important for ensuring the safety and efficiency of the vessel and its cargo. They help to:

  • Prevent damage to the cargo: By ventilating the cargo holds properly, deck air vents prevent moisture condensation, heating, gas emission, odour generation, or tainting that can affect the quality and integrity of the cargo.
  • Prevent damage to the vessel: By maintaining the pressure balance in the tanks, deck air vents prevent overpressure or vacuum that can cause structural damage to the tank walls or hull deformation.
  • Prevent fire or explosion: By removing hazardous gases from the cargo holds or fuel tanks, deck air vents prevent fire or explosion that can endanger the vessel and crew.
  • Prevent asphyxiation or poisoning: By removing hazardous gases from the cargo holds or fresh water tanks, deck air vents prevent asphyxiation or poisoning of the crew or other personnel who may enter the tanks.
  • Prevent contamination: By preventing seawater, fuel, dust, insects, or bacteria from entering the tanks through the vent pipes, deck air vents prevent contamination of the ballast water, fuel, or fresh water.

On the other hand, deck air vents also pose some risks if they are not operated or maintained properly. Some common risks include:

  • Cargo damage: If deck air vents are not opened or closed at the right time or frequency, they may cause cargo damage due to excessive or insufficient ventilation. For example, if deck air vents are opened too frequently or for too long, they may cause cargo sweat or ship sweat by introducing moist air into the cargo holds. If deck air vents are closed too early or for too long, they may cause cargo heating or gas accumulation by trapping warm air or gas inside the cargo holds.
  • Vessel damage: If deck air vents are not opened or closed properly during ballasting or de-ballasting operations, they may cause vessel damage due to overpressure or vacuum in the ballast tanks. For example, if deck air vents are not opened sufficiently during deballasting, they may cause vacuum in the ballast tanks that can suck in seawater through the vent pipes. If deck air vents are not closed sufficiently during ballasting, they may cause overpressure in the ballast tanks that can blow out seawater through the vent pipes.
  • Fire or explosion: If deck air vents are not closed properly when handling hazardous cargoes or fluids, they may cause fire or explosion due to ignition of flammable gases. For example, if deck air vents are not closed tightly when loading or unloading coal, they may allow oxygen to enter the cargo holds and ignite the coal dust. If deck air vents are not closed securely when re-fuelling or transferring fuel, they may allow fuel vapour to escape and ignite by sparks or static electricity.
  • Asphyxiation or poisoning: If deck air vents are not opened properly when entering confined spaces, they may cause asphyxiation or poisoning due to lack of oxygen or presence of toxic gases. For example, if deck air vents are not opened sufficiently before entering a cargo hold that contains carbon dioxide, carbon monoxide, methane, or hydrogen, they may cause asphyxiation or poisoning of the personnel who enter the hold. If deck air vents are not opened adequately before entering a fresh water tank that contains bacteria, they may cause poisoning of the personnel who enter the tank.
  • Contamination: If deck air vents are not fitted with proper filters, screens, covers, or caps, they may cause contamination of the tanks due to ingress of foreign substances. For example, if deck air vents are not fitted with filters that can remove dust particles from the air, they may cause contamination of the fresh water tanks by introducing dust into the water. If deck air vents are not fitted with screens that can prevent insects from entering the vent pipes, they may cause contamination of the fresh water tanks by introducing insects into the water.

In conclusion, deck air vents may seem inconspicuous, but their role in maintaining tank integrity, safety, and environmental responsibility cannot be overstated. Deck air vents are vital components of a vessel’s ventilation system that allow the passage of air in and out of the tanks onboard vessels. They serve different purposes depending on the type of tank they are fitted to, such as cargo holds, ballast tanks, fuel tanks, and fresh water tanks. Regular maintenance and prompt troubleshooting are essential to ensure their proper operation. Neglecting these critical components can result in catastrophic consequences, making them a vital focus of attention for every vessel operator. Therefore, it is essential for vessel masters and crew to understand the purpose, maintenance and troubleshooting of deck air vents onboard vessels and follow the best practices and regulations for their operation and maintenance.

If you have any questions regarding above, please feel free to use our existing forum Seafarer’s World, Telegram Chief Engineer’s Log Chat or Instagram and will try to answer to all your queries. You can use the feedback button as well!

If you like my posts, please don’t forget to press Like and Share. You can also Subscribe to this blog and you will be informed every time when a new article is published.

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Demystifying Marine Engine Crankshaft Deflection Measurements: A Comprehensive Guide

Marine engines are the heart of any seafaring vessel, powering them through the vast expanse of the ocean. Ensuring their optimal performance is crucial for the safety and efficiency of maritime operations. One vital aspect of marine engine maintenance is monitoring and interpreting crankshaft deflection measurements.

What is crankshaft deflection?

Crankshaft deflection refers to the measurement of the deviation or displacement in the centerline of the engine’s crankshaft from its ideal position during operation. It is a critical parameter that reflects the mechanical health and alignment of the engine components, particularly in large marine engines. Excessive crankshaft deflection can lead to fatigue, fracture, wear, and damage of the crankshaft and other engine components. Accurate interpretation of crankshaft deflection measurements helps prevent catastrophic failures and costly repairs, ultimately ensuring vessel safety.

If you want to learn more about crankshaft deflection please follow THIS LINK.

How to Measure Crankshaft Deflection

If you follow the above mentioned link, you will find an explanation with regard to deflection measurement.

Importance of Crankshaft Deflection Measurements

  • Early Problem Detection: Monitoring crankshaft deflection allows for early detection of mechanical issues or misalignments in the engine, preventing them from escalating into major problems that could lead to engine failure.

  • Safety Assurance: A properly aligned crankshaft is essential for the safety of the vessel and its crew. Correct alignment reduces the risk of catastrophic engine failures that could result in accidents at sea.

  • Enhanced Engine Efficiency: Correcting misalignments revealed by deflection measurements can significantly improve engine efficiency, reducing fuel consumption and environmental impact.

  • Cost Savings: Identifying and rectifying issues early on can save substantial repair and replacement costs in the long run, making crankshaft deflection measurements a cost-effective maintenance practice.

How to Interpret Marine Engine Crankshaft Deflection Measurements

Crankshaft deflection measurements are usually expressed as a table or a graph showing the values of deflection at different angular positions of the crankshaft for each unit.

Source and Credit:

The values are compared with the manufacturer’s specifications and limits to assess the condition of the crankshaft.

Interpreting crankshaft deflection measurements requires a combination of technical knowledge and practical experience. Follow these steps to ensure accurate interpretation:

  • Understand the Measurement Units: Crankshaft deflection measurements are typically expressed in micrometers (µm) or millimeters (mm). Familiarize yourself with these units and their conversion to ensure precision in your interpretations. Moreover, the dial indicator should be calibrated and checked regularly for any errors or defects. A faulty dial indicator can give false readings and lead to incorrect interpretation of deflection measurements.

For example, in the table below, U1 means unit 1, T means top position, B means bottom position, F means fuel pump side position, and E means exhaust side position. The values are in mm.

Unit T B F E
U1 0 0 0 0
U2 -0.02 +0.02 -0.01 +0.01
U3 -0.04 +0.04 -0.02 +0.02
U4 -0.06 +0.06 -0.03 +0.03
U5 -0.08 +0.08 -0.04 +0.04
U6 -0.10 +0.10 -0.05 +0.05

Plot the deflection values on a graph for each unit, using a different color or symbol for each angular position. 

Source and Credit: Marineinbox

  • Establish Baseline Measurements: Before interpreting any measurements, it’s essential to establish baseline readings for the engine when it’s in perfect condition. These baseline measurements act as a reference for identifying deviations and can be found in the engine Technical File, under Shop Trial Measurements.

  • Examine Measurement Patterns: Crankshaft deflection measurements are usually taken at multiple points along the crankshaft’s length. Analyze these measurements to identify any recurring patterns or trends. Irregularities may indicate misalignments or mechanical issues.

    • Uniformity: This is when all units show similar values of deflection within acceptable limits. This indicates that the crankshaft is in good condition and aligned properly.
    • Sagging: This is when one or more units show higher values of deflection at either top or bottom positions, indicating that the crankshaft is bending downwards due to gravity or load.
    • Hogging: This is when one or more units show higher values of deflection at either top or bottom positions, indicating that the crankshaft is bending upwards due to gravity or load.
    • Twisting: This is when one or more units show higher values of deflection at either fuel pump side or exhaust side positions, indicating that the crankshaft is twisting along its axis due to torsional forces.
    • Ovality: This is when one or more units show higher values of deflection at all positions, indicating that the crankpin or journal has become oval-shaped due to excessive wear or damage.
  • Consider Operational Conditions: It’s vital to take into account the engine’s operational conditions during measurements. Factors like load, temperature, and RPM can influence deflection readings. Comparing measurements under different conditions can provide valuable insights.

For example, the crankshaft expands and contracts with changes in temperature, which can affect the deflection values. Therefore, it is recommended to measure the deflection at a consistent temperature, preferably when the engine is cold or after a short warm-up period.

Moreover, the draught of the vessel can cause bending or twisting of the hull, which can affect the alignment of the engine and the crankshaft. Therefore, it is recommended to measure the deflection at a consistent draught, preferably when the vessel is fully loaded or unloaded.

  • Consult Manufacturer Guidelines: Manufacturers of marine engines often provide guidelines for interpreting crankshaft deflection measurements specific to their engine models. These guidelines should be consulted and followed diligently.

    • If they are within tolerance, then no action is required.
    • If they are out of tolerance, then corrective action is needed.

For example, in the table below, the manufacturer’s specifications and limits are given as:

    • Maximum permissible difference between top and bottom positions: 0.12 mm.
    • Maximum permissible difference between fuel pump side and exhaust side positions: 0.08 mm.
    • Maximum permissible difference between adjacent units: 0.04 mm.
Unit T-B Difference (mm) F-E Difference (mm) Adjacent Unit Difference (mm)
U1 0 0 N/A
U2 0.04 0.02 0.02
U3 0.08 0.04 0.02
U4 0.12 0.06 0.02
U5 0.16 0.08 0.02
U6 0.20 0.10 0.02

In this example, units U1, U2, and U3 are within tolerance, while units U4, U5, and U6 are out of tolerance. Therefore, corrective action is needed for units U4, U5, and U6.

  • Seek Expert Advice: If you’re unsure about the interpretation of deflection measurements or suspect a significant issue, it’s advisable to consult with experienced marine engineers or specialists. Their expertise can help pinpoint problems accurately.

  • Regularly Monitor and Document: Maintain a comprehensive record of all deflection measurements and their interpretations. Regular monitoring allows you to track the engine’s health over time and detect any changes or deterioration.

    Identify the possible causes and solutions for the crankshaft deflection problems, based on the shape and pattern of the graph and the manufacturer’s recommendations.

    • If the graph shows sagging or hogging, it could be caused by uneven wear of main bearings, misalignment of engine foundation, or distortion of hull structure. The possible solutions are adjusting or replacing main bearings, aligning engine foundation, or correcting hull deformation.
    • If the graph shows twisting, it could be caused by uneven firing pressures, faulty fuel injection system, or misalignment of driven unit. The possible solutions are repairing fuel injection system, adjusting firing pressures, or aligning driven unit.
    • If the graph shows ovality, it could be caused by improper lubrication, journal bearing failure, overspeeding or overloading of engine, excessive crankshaft deflection and misalignment of parts. The possible solutions are replacing crankpin or journal, improving lubrication system, reducing engine speed or load, or correcting crankshaft deflection and alignment.

In conclusion, interpreting marine engine crankshaft deflection measurements is a critical aspect of engine maintenance, ensuring vessel safety, efficiency, and cost-effectiveness. By understanding the importance of these measurements and following the steps outlined in this guide, marine engineers and ship operators can effectively monitor and maintain their engines, ensuring smooth and trouble-free voyages on the high seas.

Harnessing Engine Power Limiter (EPL) for EEXI Compliance: A Marine Engineer’s Guide

In the ever-evolving seascape of maritime regulations, the Energy Efficiency Existing Ship Index (EEXI) stands as a guiding star towards a more sustainable future. One of the critical tools in achieving EEXI compliance is the Engine Power Limiter (EPL).  In this article, we’ll dive into the significance of EPL, the challenges it poses, the available technology, and what marine engineers need to do to navigate these waters successfully.

The Essence of EPL

The Engine Power Limiter (EPL) is an integral part of a vessel’s propulsion system, designed to regulate engine power to meet the EEXI requirements. Its primary function is to limit the maximum engine power output to ensure compliance with the defined energy efficiency thresholds, ultimately reducing greenhouse gas emissions.

What is EPL and how does it work?

EPL is a system that limits the maximum engine power output in normal operating conditions, by adjusting the fuel index (the ratio between fuel flow and engine speed) with the aid of a fuel index limiter, a simple device on the ship’s engine control system. The fuel index limiter can be either mechanical or electronic, depending on the type of engine and control system.

Engine Power Limiter Source and Credit: MAN Energy Solutions

The EPL system can be overridden in emergency situations that require the use of additional power (reserve power), such as avoiding collision, maneuvering in adverse weather or responding to distress signals. The override function is activated by a switch on the bridge or in the engine room, and it triggers an alarm and a log record for reporting purposes.

The EPL system can be designed to limit either the actual engine power output or the shaft power output. The former option is suitable for ships with direct drive propulsion systems, while the latter option is suitable for ships with shaft generators or other devices that affect the power transmission from the engine to the propeller.

The level of power limitation is determined by the EEXI reduction factor, which depends on the ship type, size and age. The reduction factor ranges from 5% to 30%, meaning that the ship’s engine power must be reduced by that percentage from its original maximum continuous rating (MCR). For example, a bulk carrier built in 2010 with an MCR of 10 MW must limit its engine power to 7 MW (30% reduction) to comply with the EEXI.

Challenges on the Horizon

The main benefit of EPL is that it is a simple and cost-effective solution to achieve EEXI compliance, without requiring major modifications to the ship’s hull or propulsion system. EPL can be easily installed and retrofitted on existing ships, and it does not affect the engine’s operation under normal conditions (unless the power limit is reached).

Another benefit of EPL is that it reduces the ship’s fuel consumption and GHG emissions proportionally to the power reduction. By limiting the engine power, the ship’s speed is also reduced, which leads to lower resistance and propulsive power demand. According to some studies, a 10% decrease in speed can result in almost 30% reduction in fuel consumption and emissions.

However, implementing EPL systems presents a unique set of challenges:

  • Engineering Complexity: Installing EPL systems can be technically complex, as they must be seamlessly integrated into the existing engine control systems.

  • Data Precision: Accurate measurement and control of engine power are critical. Any discrepancies or inaccuracies in measurement could lead to non-compliance.

  • Synchronization: Coordinating engine power with vessel speed and operational demands requires precise synchronization to avoid any adverse effects on vessel performance. EPL compromise the ship’s performance, safety and operability in certain situations that require high power or speed, such as heavy weather conditions, strong currents or tides, congested waterways or ports, or contractual obligations. Therefore, EPL should be used with caution and discretion, and always considering the prevailing circumstances and risks.

  • Regulatory Adherence: Ensuring that the EPL system meets EEXI regulatory standards is essential, and this may require constant monitoring and adjustments. EPL it may not be sufficient or optimal for all ships or routes. Depending on the ship’s design characteristics, operational profile and trade pattern, other solutions may be more effective or efficient to improve the ship’s energy efficiency and reduce its emissions. For example, some ships may benefit more from hull optimization, propeller retrofitting, waste heat recovery or alternative fuels.

Technology on the Market

Several manufacturers and suppliers have developed and offered different products and solutions for EPL implementation. Some examples are:

  • Kongsberg Maritime: The company provides a software functionality called EPL upgrade for its AutoChief 600 (and AutoChief C20) remote propulsion control systems with digital governor systems (DGS). The feature enables a vessel to limit its engine power when the pre-set value is reached.

    Engine Power Limiter by Wartsila

  • Lloyd’s Register: The company has issued guidance notes for class approval of EPL and shaft power limitation (SHaPoLi) equipment, which include the requirements and procedures for the design, installation, testing and certification of such systems.

    Engine Power Limiter by MAN

  • DNV: The company offers an advisory service called EEXI vibration pre-check, which assesses the potential impact of EPL on the engine’s vibration and torsional stress levels, and provides recommendations to avoid or mitigate any adverse effects.

What Marine Engineers Need to Do

Marine engineers play a crucial role in the implementation and operation of EPL systems. They are responsible for:

  • System Assessment: Conduct a comprehensive assessment of the vessel’s current engine and propulsion systems to determine compatibility with EPL technology.

  • Technology Selection: Collaborate with technology providers to select the most suitable EPL solution, ensuring it aligns with the vessel’s specific needs and EEXI compliance requirements.

  • Integration: Installing and testing the EPL system according to the manufacturer’s instructions and the class society’s rules and regulations, ensuring its proper functioning and integration with the existing engine control system.

  • Performance Monitoring: Operating and maintaining the EPL system in accordance with the operational manual and the best practices. Implement regular monitoring and data analysis to assess the system’s performance and make adjustments as needed to maintain compliance.

  • Training: Ensure that the vessel’s crew is trained in operating and troubleshooting the EPL system effectively.

  • Documentation: Overriding the EPL system when necessary, following the safety procedures and protocols, and documenting and justifying the reasons and duration of the override events. Maintain comprehensive records of all EPL-related activities, including installation, adjustments, and performance reports, for compliance verification.

In conclusion, EPL is a viable solution for EEXI compliance that can improve the ship’s energy efficiency and reduce its emissions by limiting its engine power. However, EPL also has some challenges and limitations that need to be carefully considered and addressed. Therefore, marine engineers should be well informed and prepared to deal with EPL systems, as they are key actors in their selection, installation, operation and maintenance. With the right measures in place, EPLs can be the key to navigating these new regulatory waters with confidence.

The Importance of Air Seals on Main Engine Exhaust Valves

In the world of engineering and machinery, precision and reliability are paramount. One critical component that plays a vital role in ensuring the efficiency and performance of a combustion engine is the exhaust valve. To optimize the functioning of this crucial part, engineers have developed air seals that help maintain a secure and efficient seal. In this blog post, we will explore the significance of air seals on main engine exhaust valves, the types of air seals used, and their role in enhancing engine performance.

The Main Engine Exhaust Valve: A Crucial Component

Before diving into the intricacies of air seals, it’s essential to understand the importance of the main engine exhaust valve in a combustion engine. In an internal combustion engine, whether it’s found in a car, a ship, or an industrial machine, the exhaust valve serves a fundamental purpose. The main engine exhaust valve is a vital component of a marine diesel engine that controls the timing and duration of the exhaust gas flow from the cylinder to the turbocharger. The exhaust valve consists of several parts, such as the spindle, the housing, the seat, the hydraulic cylinder, and the air cylinder. The air cylinder is a device that uses compressed air to close the exhaust valve against the hydraulic pressure that opens it. The air cylinder has a piston that moves up and down along with the spindle, creating an air spring effect that ensures a smooth and reliable operation of the exhaust valve.

The Challenge: Gas Leakage

One of the primary challenges in designing exhaust valves is preventing gas leakage. Inefficient sealing can lead to several adverse consequences, including:

  • Reduced Efficiency: Gas leakage results in a loss of engine efficiency, as the engine must work harder to compensate for the escaping exhaust gases.
  • Environmental Impact: Incomplete combustion due to gas leakage can lead to increased emissions, contributing to air pollution and environmental degradation.
  • Increased Fuel Consumption: Gas leakage forces the engine to burn more fuel to maintain power output, leading to higher operational costs.

Types of Air Seals

To address the issue of gas leakage, engineers have developed various types of air seals, each with its own unique characteristics and applications. The air seal is a device that prevents air leakage from the air cylinder to the exhaust valve housing. It is made of a metallic outer ring and a rubber seal that contacts the spindle. The seal can have different shapes depending on the type of valve. The air seal is important for maintaining the proper air pressure and spring force in the air cylinder, as well as for protecting the spindle from corrosion and fouling by the exhaust gas. A faulty or worn-out air seal can cause air loss, reduced performance, increased fuel consumption, and higher emissions.

Exhaust valve air piston seal ring overhaul. Source and Credit: Rheinstinitz Karl Caler

Here are some common types of air seals used in main engine exhaust valves:

  • Floating Ring Seals: Floating ring seals consist of two concentric rings, with the outer ring rotating along with the valve. This design helps create a dynamic seal, minimizing gas leakage.
  • Poppet Valve Seals: Poppet valves are commonly used in internal combustion engines. They employ a cylindrical plug to control gas flow. Air seals in poppet valves help ensure a tight fit between the valve and the valve seat, preventing gas leakage.
  • Rotary Valve Seals: Rotary valves, found in some engines like rotary engines and two-stroke engines, use rotary seals to maintain a seal as the valve rotates. These seals play a crucial role in preventing gas leakage.
  • Labyrinth Seals: Labyrinth seals consist of intricate channels and ridges that create a tortuous path for gas to escape. This design effectively reduces gas leakage by increasing the distance exhaust gases must travel before exiting.

The Role of Air Seals in Enhancing Engine Performance

Air seals on main engine exhaust valves are vital for several reasons:

  • Gas Tightness: The primary function of air seals is to maintain gas tightness within the combustion chamber. This ensures that exhaust gases exit through the designated path, optimizing engine efficiency.
  • Reduced Emissions: By minimizing gas leakage, air seals contribute to lower emissions. This is especially critical in modern engines to meet stringent environmental regulations.
  • Improved Fuel Efficiency: A well-sealed exhaust valve reduces the engine’s workload, leading to improved fuel efficiency and reduced operational costs.
  • Enhanced Engine Longevity: Air seals help protect the engine from excessive wear and tear, prolonging its operational life.

The air seal on the main engine exhaust valve is a simple but important device that ensures efficient and safe operation of the engine. Therefore, it is essential to inspect and replace the air seal regularly as per the maker’s recommendations.

Example of exhaust valve overhauling. Source and Credit: DG E LEARING ADU ACADEMY

In conclusion, in the intricate world of internal combustion engines, even the smallest components play a critical role in ensuring performance and efficiency. Air seals on main engine exhaust valves are a testament to the precision and engineering prowess required to design and maintain these complex machines. By preventing gas leakage, these seals contribute to reduced emissions, improved fuel efficiency, and increased engine longevity. As technology continues to advance, we can expect further innovations in air seal designs, driving the continuous improvement of combustion engines in various applications.

If you have any questions regarding above, please feel free to use our existing forum Seafarer’s World, Telegram Chief Engineer’s Log Chat or Instagram and will try to answer to all your queries. You can use the feedback button as well!

If you like my posts, please don’t forget to press Like and Share. You can also Subscribe to this blog and you will be informed every time when a new article is published.

Also you can buy me a coffee by donating to this website, so I will have the fuel I need to keep producing great content! Thank you!

Navigating Green Waters: Propulsion and Engine Optimization for EEXI Compliance

The maritime industry is at the helm of significant change as it sails toward a more sustainable future. With the Energy Efficiency Existing Ship Index (EEXI) regulation coming into effect in 2024, vessel owners and operators are tasked with optimizing propulsion systems and engines to reduce greenhouse gas emissions. If you want to read more about EEXI please follow THIS LINK.

In this article, we’ll dive into the challenges, available technology, and what marine engineers need to do to navigate this sea of change successfully.

Challenges on the Horizon

Complying with the EEXI regulation presents several challenges, primarily centered around improving energy efficiency while minimizing emissions. Some of the key challenges include:

  1. Evaluating Existing Systems: Vessel owners must assess their current propulsion and engine systems to determine their energy efficiency and EEXI compliance. This often requires complex calculations and data analysis.

  2. Investment Costs: Upgrading propulsion systems and engines can be a significant investment. Owners need to balance these costs with the long-term benefits of improved efficiency and compliance.

  3. Technology Integration: Implementing new technologies and optimizing engines can be a complex process. Ensuring these systems work seamlessly with existing onboard systems is crucial.

  4. Regulatory Compliance: Meeting EEXI requirements necessitates compliance with stringent emissions standards. Staying up to date with evolving regulations is an ongoing challenge.

Technology on the Market

To address these challenges, a range of innovative technologies and solutions are emerging in the maritime sector:

  1. Fuel-Efficient Engines: Modern, fuel-efficient engines with advanced combustion technologies and improved design are becoming more widely available.

  2. Exhaust Gas Cleaning Systems: Technologies like scrubbers and selective catalytic reduction (SCR) systems help reduce emissions from engines, aligning with EEXI standards. More about this if you follow THIS LINK.

  3. Alternative Fuels: The adoption of alternative fuels such as LNG, hydrogen, and ammonia can significantly reduce greenhouse gas emissions.

  4. Energy Recovery Systems: Systems that recover and reuse waste energy from the engine, such as waste heat recovery systems, contribute to greater efficiency.

  5. Propulsion Efficiency Solutions: Upgrading propulsion systems with modern propellers and thrusters designed for efficiency can reduce fuel consumption.

    Source and Credit: MOL

    One of the most common methods to improve the attained EEXI is to limit the engine power or shaft power of the ship. This can be done by re-setting the fuel index by limiting the fuel rack using either mechanical stop or setting the control system in combination with an approved override functionality as defined in the IMO guidelines. This method is called Engine Power Limitation (EPL) or Shaft Power Limitation (ShaPoLi). To read more about this, please follow THIS LINK.

    However, this method also poses some challenges and risks for the ship operation, such as reduced maneuverability, increased fuel consumption, increased maintenance costs, and potential safety issues.

    Therefore, ship operators need to consider other measures to optimize the propulsion and engine performance of their ships, such as installing energy saving devices, using alternative fuels, or upgrading the propulsion system. Some of the available technologies on the market that can help achieve this are:

    • FuelOpt: This is a propulsion optimization system developed by Yara Marine Technologies that provides an integrated ShaPoLi feature that complies with the EEXI framework. The system enhances vessel efficiency while minimizing the impact of engine or shaft power limitations on daily operations. FuelOpt can also reduce fuel consumption and emissions by controlling the propeller pitch and engine load in real time.
    • Rotating sails: These are vertical cylinders that rotate around their axis and use the Magnus effect to create a forward thrust. They can be installed on existing ships as an auxiliary propulsion system that can reduce fuel consumption and emissions by up to 20%. Some examples of rotating sails are Flettner rotors and Norsepower rotor sails .
    • Bulbous bow: This is a protruding bulb at the bow of a ship that modifies the water flow around the hull and reduces the drag. It can improve the hydrodynamic efficiency of a ship and reduce fuel consumption and emissions by up to 15%. However, it requires careful design and optimization for different ship types and speeds.
    • Propeller fins: These are appendages attached to the propeller blades that increase the thrust and efficiency of the propeller. They can reduce fuel consumption and emissions by up to 5%. Some examples of propeller fins are Becker Mewis Ducts and Propeller Boss Cap Fins .
    • Alternative fuels: These are fuels that have lower carbon intensity than conventional marine fuels, such as liquefied natural gas (LNG), biofuels, hydrogen, ammonia, or methanol. They can reduce greenhouse gas emissions from ships by up to 100%, depending on their production and use. However, they also require new infrastructure, storage, handling, and safety measures.
    • Propulsion systems: These are systems that convert energy into propulsive force, such as diesel engines, electric motors, gas turbines, or fuel cells. They can be upgraded or replaced with more efficient or low-carbon technologies that can reduce fuel consumption and emissions. Some examples of propulsion systems are hybrid propulsion, diesel-electric propulsion, or hydrogen fuel cell propulsion .

What Marine Engineers Need to Do

Marine engineers play a pivotal role in ensuring vessels comply with EEXI regulations and optimizing propulsion and engine systems. Here’s what they should consider:

  1. Data Analysis: Conduct detailed data analysis to determine the current energy efficiency of propulsion and engine systems. This forms the foundation for improvement strategies.

  2. Collaboration: Collaborate with naval architects, designers, and technology providers to select the most suitable propulsion and engine optimization solutions.

  3. Regular Maintenance: Implement a rigorous maintenance schedule to keep engines and propulsion systems in optimal working condition, reducing energy wastage.

  4. Training: Stay up to date with the latest technologies and best practices through continuous education and training programs.

  5. Monitoring and Reporting: Implement systems for real-time monitoring of engine and propulsion system performance. Regularly report on energy efficiency improvements and emissions reductions.

  6. Documentation: Maintain comprehensive records of all upgrades, modifications, and maintenance activities related to propulsion and engines for compliance verification.

The EEXI regulation is expected to have a significant impact on the shipping industry in 2024 and beyond. As the maritime industry charts a course towards greater sustainability, marine engineers are the navigators guiding vessels through these uncharted waters. By leveraging the available technology and adhering to best practices, marine engineers can help vessel owners and operators meet the challenges of EEXI compliance while contributing to a cleaner, greener future for the maritime world.