Tytuł: A Comparative Analysis of Hydrogen Fuel Cells and Internal Combustion Engines Used for Service Operation Vessels Propulsion

Autor/Autorzy: Bortnowska M., Zmuda A.

Miejsce publikacji: Energies

Rok: 2025

Słowa kluczowe:  fuel cells, hydrogen fuel, service offshore vessel (SOV)

Abstrakt: In response to the IMO’s decarbonisation strategy, hydrogen—especially green hydrogen—becomes a promising alternative fuel in shipping. This article provides a comparative analysis of two hydrogen propulsion technologies suitable for a service vessel (SOV) operating in offshore wind farms: hydrogen fuel cells and hydrogen-powered internal combustion engines. This study focuses on the use of liquid hydrogen (LH2) stored in cryogenic tanks and fuel cells as an alternative to the previously considered solution based on compressed hydrogen (CH2) stored in high-pressure cylinders (700 bar) and internal combustion engines. The research aims to examine the feasibility of a fully hydrogen-powered SOV energy system. The analyses showed that the use of liquefied hydrogen in SOVs leads to the threefold reduction in tank volume (1001 m3 LH2 vs. 3198 m3 CH2) and the weight of the storage system (243 t vs. 647 t). Despite this, neither of the technologies provides the expected 2-week autonomy of SOVs. LH2 storage allows for a maximum of 10 days of operation, which is still an improvement over the CH2 gas variant (3 days). The main reason for this is that hydrogen tanks can only be located on the open deck. Although hydrogen fuel cells take up on average 13.7% more space than internal combustion engines, they are lower (by an average of 24.3%) and weigh less (by an average of 50.6%), and their modular design facilitates optimal arrangement in the engine room. In addition, the elimination of the exhaust system and lubrication simplifies the engine room layout, reducing its weight and space requirements. Most importantly, however, the use of fuel cells eliminates exhaust gas emissions into the atmosphere.

Adres strony internetowej (link) do pełnego tekstu publikacji: https://www.mdpi.com/1996-1073/18/19/5104

 DOI: 10.3390/en18195104

Tytuł: The Possibility of Using Hydrogen as a Green Alternative to Traditional Marine Fuels on an Offshore Vessel Serving Wind Farms

Autor/Autorzy: Bortnowska M., Zmuda A.

Miejsce publikacji: Energies

Rok: 2024

Słowa kluczowe: hydrogen fuel, composite tanks, SOV vessel

Abstrakt: Achieving the required decarbonisation targets by the shipping industry requires a transition to technologies with zero or near-zero greenhouse gas (GHG) emissions. One promising shipping fuel with zero emission of exhaust gases (including CO2) is green hydrogen. This type of fuel, recognised as a 100% clean solution, is being investigated for feasible use on a service offshore vessel (SOV) working for offshore wind farms. This study aims to examine whether hydrogen may be used on an SOV in terms of the technical and economic challenges associated with the design process and other factors. In the analyses, a reference has been made to the current International Maritime Organization (IMO) guidelines and regulations. In this study, it was assumed that hydrogen would be directly combusted in a reciprocating internal combustion engine. This engine type was reviewed. In further research, hydrogen fuel cell propulsion systems will also be considered. The hydrogen demand was calculated for the assumed data of the SOV, and then the volume and number of high-pressure tanks were estimated. The analyses revealed that the SOV cannot undertake 14-day missions using hydrogen fuel stored in cylinders on board. These cylinders occupy 66% of the ship’s current volume, and their weight, including the modular system, accounts for 62% of its deadweight. The costs are over 100% higher compared to MDO and LNG fuels and 30% higher than methanol. The actual autonomy of the SOV with hydrogen fuel is 3 days.

Adres strony internetowej (link) do pełnego tekstu publikacji: https://www.mdpi.com/1996-1073/17/23/5915

 DOI: 10.3390/en17235915

Tytuł: Design analysis of an innovative concept of a displacement motor yacht with eco-drive

Autor/Autorzy: Bortnowska M. , Kapała D.

Miejsce publikacji: Scientific Journals of the Maritime University of Szczecin

Rok: 2024

Słowa kluczowe:  conceptual design, futuristic motor yacht, electric propulsion, stability analysis

Abstrakt: In response to the challenges of environmental protection and the need to be close to nature and to reconnect with it, an unusual motor yacht design is developed with an abstract architectural form modeled on an armadillo. Due to the innovative form of the hull, a specific approach to pre-design is used, with the research objective of verifying that for the organic form of the hull, it would be possible to meet all the design criteria and regulations required for the design of a yacht. This article first characterizes the initial assumptions and then presents the process of determining the main dimensions with simultaneous modification of the hull shape. In order to maintain the basic dimensional proportions, based on the classic motor yacht, the recommended values of design factors are controlled. Moreover, the hydrostatic parameters of the unconventional hull shape are calculated. As a result of preliminary resistance and propulsion analyses, a propulsion system in the form of electric motors is selected, and, to meet emission requirements, the use of photovoltaic panels is additionally proposed. A stability and equilibrium analysis is carried out for one of the load cases and checked with the requirements of the Polish Register of Shipping (PRS) rules. The design of the hull of the yacht, covered in an interesting form of scales, together with the layout of the yacht’s interior, is presented in three-dimensional form, bringing the conceptual idea to life. The result of the design work and analysis is an inspiring hull shape based on nature, complying with the design guidelines and regulations that apply to yacht design.

Adres strony internetowej (link) do pełnego tekstu publikacji: https://repository.am.szczecin.pl/handle/123456789/2811

 DOI: 10.17402/594

Tytuł: Projected Reductions in CO2 Emissions by Using Alternative Methanol Fuel to Power a Service Operation Vessel

Autor/Autorzy: Bortnowska M.

Miejsce publikacji: Energies

Rok: 2023

Słowa kluczowe: alternative fuel, decarbonization, LNG, methanol, Service Operation Vessel (SOV), EIV index

Abstrakt: Due to increasingly stringent IMO and European Commission requirements for greenhouse gas emissions, the present study analysed the projected reductions in CO2 emissions achieved by using methanol as an alternative fuel to power custom service operation vessels (SOVs) serving wind platforms in the Baltic Sea. Methanol is a relatively new fuel, approved for use as a safe marine fuel in the late 2020s. In these analyses, reference was made to the current interim guidelines, supplementing the IGF Code in the form of MSC.1/Circ.1621. The SOV type was chosen because of the current growing demand for these ships (the dynamic development of offshore wind power) and the lack of analyses of this type of small craft. The importance of assessing CO2 emissions in this case is due to the specifics of the vessel’s operation in different modes, and thus the variable load on the propulsion system and the area of operation close to the coastline. A computational research method was used to evaluate CO2 emissions, as well as the cost of methanol fuel, using current regulations and technical data. A comparison was also made between conventional MDO and LNG fuels. The first results of the analysis showed that methanol fuel is only competitive with MDO (a few-percent advantage) in terms of the average estimated index value EIV. Economically, it will require a higher investment, despite the favourable unit price of methanol compared to LNG and MDO.

Adres strony internetowej (link) do pełnego tekstu publikacji: https://www.mdpi.com/1996-1073/16/21/7419

 DOI: 10.3390/en16217419