AN SE BASED MARITIME VESSEL DEVELOPMENT FRAMEWORK FOR CHANGEABLE PROPULSION SYSTEMS

The Energy Efficiency Design Index (EEDI) serves as a key measure of a ship’s environmental performance and an indicator of its energy efficiency. For seagoing vessels, the International Maritime Organization (IMO) used comprehensive ship data from the ‘IHS Fairplay database’ to establish EEDI baselines. Although the IMO introduced energy efficiency standards for ships over a decade ago, these regulations have not yet been applied to inland navigation. As a result, inland waterway vessels are exempted from the mandatory energy efficiency requirements. This regulatory gap limits the adoption of more energy-efficient designs that could reduce the environmental impact in inland shipping. Inland general cargo vessels play a significant role in the transportation of goods and optimizing their energy efficiency is crucial for minimizing emissions and improving sustainability. This paper presents an in-depth analysis of EEDI calculations based on IMO’s energy efficiency framework to suit inland cargo vessels, with vessel types representative of those operating in the Indian subcontinent. Additionally, the paper explores the effects of various fouling scenarios on energy efficiency and investigates how emissions can be reduced by employing various energy efficiency measures tailored to inland waterways. According to the Directorate General of Shipping (DG shipping), Government of India, the annual fuel consumption report for 2021 indicates that 69% of diesel/gas oil consumptions comes from ships of less than 5000 GT, that are operating on domestic routes. Moreover, these smaller vessels account for 18-19% of total carbon emissions from Indian ships. With projected increase in carbon emissions, it is crucial to prepare for emission indices applicable for inland water ways that allow the inland shipping towards a greener environment. The current study serves as a foundational step towards achieving sustainable goals in inland waterways. Given the significant impact of these emissions, it is essential to assess the data quality and operational parameters of the vessels operating in the inland waterways to ensure accurate EEDI calculations. Field studies reveal discrepancies between actual measurements and existing design data mainly in the principal particulars, main and auxiliary engine powers, and design speed. All this deviated ship information has a high influence on EEDI values. For this reason, ship data should be verified to find the correct ones, which is the key factor to establish EEDI baselines for inland going vessels. For the current study, data from 441 Indian general cargo vessels operating in inland waterways are considered, and the analysis of the data revealed instances of ambiguous or faulty information. Verified data from this analysis was then used to propose new EEDI baselines for inland cargo vessels. The proposed EEDI line represents CO2 emissions per tonne-mile and highlighting the necessity of precise operational data for effective calculation. Additionally, the validation of bio-fouling impacts on the EEDI is also conducted by referencing different fouling stages over various years.

This paper explains and evaluates the development of Part IV to Annex VI of the MARPOL Convention which was adopted in July 2011. The addition to Annex VI contains new rules regulating the energy efficiency of ships. In particular, Part IV introduces the so-called Energy Efficiency Design Index (EEDI) which will require all new ships to meet specific energy efficiency targets. One of the striking features of the negotiation process of the EEDI was the failure to achieve a consensus amongst IMO Member States. In particular, there was disagreement on the application of the principle of common but differentiated responsibilities to the shipping sector. In its final form, the EEDI is designed to apply to all ships, regardless of which flag they fly. However, several large developing countries voted against the new rules which raises doubts as to whether the EEDI will apply universally, particularly as these states will be able to avoid their application through the exercise of their right to object to amendments under the MARPOL Convention. In response to this problem, this paper considers the options that are available to proponents of the new scheme to promote its application to all ships, including states which are not formally bound to comply with the EEDI. The paper argues that whilst there are some strategies that can be used by those states which support the EEDI to promote their application, particularly through port state measures, these strategies only offer a sticking plaster. Universal application can only be achieved through a political solution.

Within the commitment of the International Maritime Organization to control the impact of shipping on climate change, the development and recent adoption of the Energy efficiency design index (EEDI) as a measure towards curbing CO2 emissions from shipping mandates that all new ships will have to meet a gradually increased level of energy efficiency, hence ensuring that more efficient newbuildings will replace those withdrawn from service. In this article, the Ro-Pax and passenger ships operating within the domestic shipping network of Greece make a suitable reference for an EEDI analysis because of the significant number of ships deployed, whereas their design diversity provides a test for the reliability of the EEDI approach in this shipping sector. It was found that large-sized Ro-Pax vessels showed a strong negative correlation between EEDI values and gross tonnage, which is consistent with the results of other relevant studies. In a market which is characteristic of diverse vessel designs, it was demonstrated that the “EEDI baseline” calculation is highly influenced by vessel design and operational characteristics, dictating the need for close monitoring of the EEDI effectiveness in this sector.

The increase of ship’s energy utilization efficiency and the reduction of greenhouse gas emissions have been high lightened in recent years and have become an increasingly important subject for ship designers and owners. The International Maritime Organization (IMO) is seeking measures to reduce the CO2 emissions from ships, and their proposed energy efficiency design index (EEDI) and energy efficiency operational indicator (EEOI) aim at ensuring that future vessels will be more efficient. Waste heat recovery can be employed not only to improve energy utilization efficiency but also to reduce greenhouse gas emissions. In this paper, a typical conceptual large container ship employing a low speed marine diesel engine as the main propulsion machinery is introduced and three possible types of waste heat recovery systems are designed. To calculate the EEDI and EEOI of the given large container ship, two software packages are developed. From the viewpoint of operation and maintenance, lowering the ship speed and improving container load rate can greatly reduce EEOI and further reduce total fuel consumption. Although the large container ship itself can reach the IMO requirements of EEDI at the first stage with a reduction factor 10% under the reference line value, the proposed waste heat recovery systems can improve the ship EEDI reduction factor to 20% under the reference line value.

Enlarging the fleet of gas carriers would make it possible to respond to the growing demand for hydrocarbon gases, but it will increase carbon dioxide emissions. The International Maritime Organization (IMO) has developed the energy efficiency design index (EEDI) with the objective of carbon emission reduction for new ships. In this paper, thirty gas carriers transporting liquefied natural gas (LNG) and liquefied petroleum gas (LPG) and equipped with various types of main engines are considered. As shown by the calculation of the attained EEDI, 2 of the 13 LPG carriers and 6 of the 17 LNG carriers under study do not comply with the EEDI requirements. To meet the stringent EEDI requirements, applying thermochemical regenerators (TCRs) fed by main engine exhaust gases is suggested. Mathematical modeling is applied to analyze the characteristics of the combined gas-turbine-electric and diesel-electric power plant with thermochemical recuperation of the exhaust gas heat. Utilizing TCR on gas carriers with engines fueled by syngas produced from boil-off gas (BOG) reduces the carbon content by 35% and provides the energy efficiency required by IMO without the use of other technologies.

The international maritime organization (IMO) has worked since 2009 to minimize harmful gas emissions from marine traffic. Due to its worldwide climate effect, IMO has implemented an energy efficiency design index (EEDI) to monitor and quantify CO2 emissions. Due to 1.0-meter wave height, Maluku waters remain quiet. For transporting from distant, outermost, and border places, feeder ships will work better. The three-body vessel (trimaran) has a vast deck surface and can efficiently feed tiny islands. This study analyzes trimaran vessel EEDI and resistance using Froude number Fr = 0.21 speed and transverse distance S/L = 0.2, 0.3, 0.4, and 0.5. Experimental calculations show a large fluctuation in hull distance. The trimaran ships with S/L=0.5 have the least resistance and essentially equal calculation results to independent trimarans. This shows that the trimaran with a 0.5 hull ratio has little hull interference. For trimaran ships, EEDI estimates suggest operating below Fr=0.21, which meets IMO criteria.

The introduction of the energy efficiency design index (EEDI) and ballast water treatment regulations by the International Maritime Organization, the fluctuation of fuel price levels, along with the continuous endeavor of the shipping industry for economic growth and profits has led the shipbuilding industry to explore new and cost-efficient designs for various types of merchant ships. In this respect, proper use of modern computer-aided design/computer-aided engineering systems (CAD/CAE) extends the design space, while generating competitive designs with innovative features in short lead time. The present article deals with the parametric design and optimization of containerships. The developed methodology, which is based on the CAESES/Friendship-Framework software system, is demonstrated by the conceptual design and multiobjective optimization of a midsized, 6500-TEU containership. The methodology includes a complete parametric model of the ship’s external and internal geometry and the development and coding of all models necessary for the determination of the design constraints and the design efficiency indicators, which are used for the evaluation of parametrically generated designs. Such indicators defining the objective functions of a multiobjective optimization problem are herein the EEDI, the required freight rate, the ship’s zero ballast container box capacity, and the ratio of the above to below deck number of containers.The set-up multiobjective optimization problem is solved by use of the genetic algorithms, and clear Pareto fronts are generated. Identified optimal design proves very competitive compared with the standard containership designs in the market.

After introducing an energy efficiency design index (EEDI) in 2011, International Maritime Organization (IMO) pursued their short- and long-term goals to reduce greenhouse gas (GHG) emissions from ships by presenting, among others, an energy efficiency existing ship index (EEXI). Contrary to EEDI which is used for new ships solely, EEXI is addressing an energy efficiency of already built ships and is set to become formally applicable starting from 2023. Existing designs cannot be essentially and rapidly changed to comply the criterion. The only main particular from the preliminary design phase that can be meaningly optimized “post festum” is a required engine power, and thus, the speed. Therefore, the paper explores the effect of EEXI policy on a fleet of 153 bulk carriers built between 2000 and 2020 in order to address their near future and prompt design changes, specifically considering the power reduction. For that purpose, an attained and a required EEXI are calculated for each ship. The results showed that only 15% of the ships built in 2000-2012 satisfied 2013-2014 IMO criterion. This impacted the design of ships built in 2013-2022, as they complied the same criterion by 88% of share. However, no ship from the whole database satisfied the present day EEDI requirement and only one ship fulfilled the contemporary EEXI requirement meaning that the current designs are not able to match the emerging criteria to a large extent. In order to meet an energy efficiency criterion, a main engine power reduction and speed are predicted assuming that the engine power and shaft limiter are installed. The investigation showed that MCR reduction of the total fleet taken into account had to be reduced by 50% and speed by 15% on average in order for ships to meet current requirements. Moreover, a graphic method is developed for the estimation of EEXI by using only deadweight (DWT) and maximum continuous rating (MCR). The proposed simplified method based on average values could be used on existing bulk carriers with an aim to satisfy novel regulation with application of “easy to use” approach. Additionally, authors discussed other options to reliably evaluate an energy efficiency of existing ships.

The Energy Efficiency Design Index (EEDI) is made mandatory by the International Maritime Organization to reduce emissions of greenhouse gases from international shipping. In this study, wave energy recovery using a pair of hydrofoils fixed at the ship bow to realize energy efficient propulsion is proposed. This so-called wave devouring hydrofoil (WDH) functions both as an anti-motion fin and a wave energy device, which can help reduce the ship wave added resistance, heave and pitch responses. To evaluate its performance, the coupled interaction between the hydrofoils and the ship under head sea condition is first modeled in the frequency domain together with the evaluation of wave added resistance in the presence of the WDHs. Model test is then conducted using a sample containership. Both the beneficial effect of the WDHs and the validity of the numerical model are proved. The peak response is reduced by 80%, 30% and 25% for added resistance, heave and pitch, respectively. This model is then further modified to include other wave directions. Based on frequency domain results, short-term and long term predictions of speed loss, engine power increase and propeller racing are performed for a 3100TEU containership along her transportation route. The merit of this prediction model is that the hull -propeller -engine interactions is considered from a system balance point of view. It is demonstrated that the WDHs can contribute to the energy-efficient ship propulsion at actual seas, achieving a slight reduction of EEDI and ensuring less speed loss and propeller racing.

Total shipping accounts for 2.9 % of the annual average percentage of global anthropogenic GHG emissions. The International Maritime Organization implements EEDI (Energy Efficiency Design Index), Energy Efficiency eXisting-ship Index (EEXI), and Carbon Intensity Indicator (CII) as regulatory frameworks for shipping decarbonization. The Republic of Korea has enforced the Act on Development and Popularization of Greenship from 2020 and publicly announced the 1st national plan which was named 『2030 Greenship-K Promotion Strategy』 for the activation of a greenship market. The Greenship Certification Scheme is going on for the sustainability of Korean shipbuilding and shipping industries, to secure clean maritime environments, as well as to contribute to the national economy. Greenship Certification guarantees the credit of such eco-friendly technologies and products for shipping. The certification is going to be the basis of industrial competitiveness in coastal and international shipping. This study investigates an existing certification process, identifies the limitations, and proposes the process improved with several case studies. The improved certification scheme may have rationality for Net-zero with regard to climate alignment.

The speed/power performance of a ship is nowadays not only a contractual, but also a statutory requirement. Thus, it is essential to know the true speed/power performance of the ship, as verified by conducting sea trials before the delivery. Presently, relevant guidelines of the International Maritime Organisation (IMO) include two alternatives for the verification of the speed/power performance of a ship in relation to the calculation of a ship’s Energy Efficiency Design Index (EEDI), namely, the ITTC Recommended Procedure 7.5-04-01-01.1 Speed and Power Trials: 2017 and the ISO 15016:2015 procedure, while noting that ITTC recently revised its recommended procedure and the same is underway for the ISO 15016. In this paper, we will re-analyze the sea trial results of a series of tanker sisterships tested under different conditions, by applying the newly updated ITTC procedure to assess the actual speed-power performance of the ships. In particular, the influence of applying alternative methods in analyzing the sea trial results and the effect of environmental conditions on the achieved speed performance are investigated. The results are very important for many stakeholders of the maritime industry, especially for designers in developing new EEDI compliant ships, for shipbuilders and for shipping companies in planning their new buildings and retro-fittings in view of the implementation time frame of EEDI/EEXI.

The International Maritime Organisation (IMO) is setting clear and ambitious goals for the decarbonisation of the shipping industry through the introduction of new regulations like the Energy Efficiency Design Index (EEDI), Energy Efficiency Existing Ship Index (EEXI) and Carbon Intensity Indicator (CII). However, these new regulations do not cover mobile offshore units like the Floating Production Storage and Offloading (FPSO) units that fall under the same maritime regime. To embrace sustainability in their corporate strategies and improve their public image, it is in the interest of existing oil and gas companies and operators to embark on a program of abating Greenhouse Gas (GHG) emissions through careful measurement and analysis. This paper is aimed at providing an overview of the typical FPSO’s GHG emissions that originates from sources such as power generation, flaring, leakages and tank venting. The paper goes in-depth concerning some potential abatement measures that can be taken to reduce such emissions. This is followed by a case study of an FPSO assessed for the voluntary DNV class notation, Abate, to discuss how a competent third-party like DNV can play a significant role in helping offshore oil and gas companies demonstrate and achieve abatement in GHG emissions from their assets.

Eco-friendly technologies are already on the rise in most marine and offshore industries. Ship owners, shipbuilders and paint manufacturers have seriously considered reduction of VOCs (Volatile Organic Compounds) and CO2 emission. Also, IMO (International Maritime Organization) has enacted new regulations through MEPC (Marine Environment Protective Committee) 63 in 2011. Accordingly, shipbuilders should design vessels based on the EEDI (Energy Efficiency Design Index) and ship owners should incorporate SEEMP (Ship Energy Efficiency Management Plan) regulations beginning January 2013. On the other hand efficiency of the vessel is a very important issue because it is very closely associated with cost too. Regarding all of these issues, many ship owners prefer using silicone FRC (Foul Release Coating) commonly called “Silicone paint” to reduce maintenance costs and meet environmental restrictions. However, this material needs a different application method compared with a conventional SPC (Self Polishing Copolymer) Anti-Fouling coating. Consequently shipbuilders are concerned with FRC application not only during construction but also after delivery. This is due to the workability of the material, and safety protection, overspray contamination with silicone based material and slippage issues etc. In this study, we have investigated several potential defects and suggested troubleshooting with an effective plan for dealing with FRC, applied in the field.

Field operation of a 125kW ORC with ship engine jacket water

With the implementation of the energy efficiency design index (EEDI) by the International Maritime Organization (IMO), the goal of which is to reduce greenhouse gas (GHG) emissions, interest in energy saving devices (ESDs) is increasing. Among such ESDs are air lubrication methods, which reduce the frictional drag of ships by supplying air to the hull surface. This is one of the efficient approaches to reducing a ship’s operating costs and making it environmentally friendly. In this study, the air lubrication method on a flat plate was studied using computational fluid mechanics (CFD). OpenFOAM, the open-source CFD platform, was used. The coupled level-set and volume of fluid (CLSVOF) solver, which combines the advantages of the level-set method and the volume of fluid method, was used to accurately predict the air and water interface. Rayleigh–Taylor instability was simulated to verify the CLSVOF solver. The frictional drag reduction achieved by the air lubrication of the flat plate at various injected airflow rates was studied, and compared with experimental results. The characteristics of the air and water interface and the main factors affecting the cavity formation were also investigated.