Stolt tankers is the largest operator of deep-sea chemical parcel tankers. Parcel tankers differentiate form bulk chemical tankers by the additional features that the ships have, such as cargo cooling, cargo heating, many (small) cargo tanks, highest level of chemical resistant materials and notation to carry the most dangerous chemicals. These features make the parcel tanker versatile compared to other tanker types, however this results in a higher cost. In the last twenty years, a shift has taken place in the deep-sea chemical shipping industry, driven by changes in regulations, funding of ships and macroeconomic factors. These changes have made the playing field of deep-sea chemical tankers more equal and commoditised, resulting in more competition by entries of new, privately funded companies with simple chemical tankers. Currently a large part of the parcel tanker fleet is nearing their end of lifetime and are expected to be recycled in the next five years. This creates the need to determine operating needs and requirements for replacements of Stolt Tankers’ ageing parcel tanker fleet. The goal of this study is twofold, first, is to determine the need for parcel tanker features in the market and, secondly, to determine the value that these features add. The findings have been concluded in terms of a priority for the feature in a new parcel tanker specification according to the MoSCoW prioritising technique.Analysis of the features is based on D37 parcel tanker class of Stolt Tankers. This typical parcel tanker class is a candidate for recycling in the next 5 years, and therefore a ideal study object for a replacement study. Four features were identified as giving the highest differentiation of a parcel tanker and are analysed in more detail: cargo cooling, cargo heating with thermal oil heating medium, small cargo tanks, and ship type 1notation. These features are analysed both qualitatively and qualitatively on its operation in the Stolt fleet, market demand and supply, competition and alternatives. The net added value of the features over the life of the ship has been calculated by means of a discounted cash flow analysis for base-,best and worst case scenarios.The cargo cooling feature yields the best added value for a new parcel tanker. The thermal oil cargo heating feature has a negative added net present value for only cargoes with this specific requirement. The study of the ship type notation has a low investment cost, however the loss of revenue by the capacity reduction is far more than potential revenues from thetype 1 cargoes. The number of cargo tanks has a large impact of the capital cost of the ship.Reducing the number of cargo tanks, i.e. the average tank size, yields a relatively large savingfor parcel tanker ship types. Combined with a decrease in the number of small cargoes, makes this a logical development for future parcel tankers. However, more research is required since there is a large discrepancy between the number of small cargoes on different trade routes.Based on the findings from the market and operational review of the D37 features the following priorities are given to the features. The cargo cooling system has been given a’Should Have’priority, the thermal oil cargo heating system has a’Could Have’and the ship type 1 notation a’Won’t Have’. Further research is recommended for the requirement of features of new ships with respect to the total fleet of Stolt Tankers. Secondly, modelling of cargo tank layouts with the statistical trading data is recommended to determine the requirements for the number and sizes ranges of cargo tanks

Nowadays the interest for environmental issues is steadily gaining ground. Inescapably, the shipping industry, is also called to contribute its fair share towards the reduction of air pollution. Harbour tugboats need to comply both with international but also with local exhaust air emission regulations, which are anticipated to become more stringent in the future. Kotug, is interested to proactively explore suitable powering solutions, which can be applied at its Rotortugs’ newbuilding scheme, to comply with upcoming regulations of the intended port of operation. The goal of this thesis is to develop a decision-support tool to facilitate the selection process between alternative prime mover combinations, based on what is needed in terms of operation while considering technical challenges, environmental performance and economic returns. The effect of a variety of promising alternative fuels matched with suitable prime movers was investigated for the period 2018-2033, which was set as the study’s time horizon. LNG, Methanol, Biodiesel and DME were assessed as feasible solutions. The first two were associated with gas-burning engines, whereas the rest were associated with conventional 4-stroke compression ignition engines, similar to the ones already installed in the existing Rotortugs running on MGO. The environmental performance differs substantially to a conventional prime mover running on MGO. However, to adhere to future stricter regulations in certain sea areas, additional after-treatment systems are necessary. Research indicated three post-treatment solutions are the most effective in limiting the majority of the combustion-related emissions; Selective catalytic reduction, diesel particulate filter and oxidation catalysts. The total environmental fingerprint of a vessel can be however assessed only under the context of its propulsion configuration layout. The operational profile of a tugboat is highly variable, allowing room for the exploitation of different drivetrains than the traditional diesel-direct layout, which could lead in benefits mainly in terms of fuel efficiency and maintenance savings. Three drivetrains were selected; a diesel-electric and two hybrid, based on AC and DC topology. Before deciding to invest on a future boat a ship-owner is expected to be eager to comprehend the cost-related issues between alternatives. Moreover, the already proven design of the diesel-direct Rotortug, complemented by the necessary after-treatment technologies, makes sense to be the first option to consider, provided it complies with the anticipated regulations. This option is considered the baseline case. It is reasonable to compare all other options against the baseline case. To this end, a decision framework based on a techno-economic evaluation is proposed for supporting ship-owners to take informative decisions on investment considerations; Three objectives were set; economic performance, environmental performance and cost-effectiveness. To quantify economic performance a comparative TCO analysis was implemented, while for environmental performance the emission output of alternatives is compared. Last, cost-effectiveness adds valuable insight into how good money are allocated towards emission reduction targets and provides a methodology to compete for funding from a regulatory authority. Two case studies are presented that demonstrate the utility of these methods and enhance the understanding of the impact of decisive factors in decision-making. It is concluded that the proposed decision-support tool enables decision-support at an early-stage; nonetheless can still be improved, by incorporating additional factors and expanding certain modules with more details.

An issue that arises during the execution of shipbuilding engineering projects at Royal IHC is an imbalance between the sum of all necessary engineering work, and all engineers that are employed who are available to execute the work. This research aims to develop a new method to help establish a proposal engineering work schedule forecast for all engineering work packages in custom trailing suction hopper shipbuilding projects at Royal IHC. To develop the input for the new method, regression analysis on usable historical engineering man-hour data was applied to develop models that quantify work, and curve fitting through the man-hour data was applied to develop models that determine the timing of work.

The first large offshore wind farms installed in the North Sea Region (NSR) soon reach their technical end of lifetime. The wind turbines in these farms will have to be decommissioned after power production has stopped. Currently offshore wind turbines are decommissioned based on a method called reversed installation, a time consuming and therefore costly operation. This report focuses on the situation regarding decommissioning of offshore wind turbines (excluding foundations), and unveils the possibilities of potential decommissioning methods, using a jack-up, in an effort of to obtain a more cost-effective and environmentally friendly method than the currently used reversed installation. The act of decommissioning is explained, together with the expected market of decommissioning in the North Sea Region. Legislation concerning decommissioning of the five largest offshore wind producing countries in Europe are discussed. Using a multi criteria analysis on demolition methods, floating alternatives, and a model (determining the transport configuration), the most economical and least energy consuming combination is chosen. This model shows an economization of up to 66% and cutting the energy consumption by a third. Lastly, these outcomes are applied to three separate business cases including a sensitivity analysis to show the effect that variations in input values have on the results.

Maritime transport covers about 90%of world trade and is seen as one of the most cost-effective way of transporting goods. In order to safely accommodate vessels calling into ports, tugs are operated to assist various sized vessels with navigating, manoeuvring and berthing. Competition within the ship handling market has always been fierce. Boskalis Towage, through a network of joint ventures, offers harbour- and terminal towage services around the world, comprised of about 450 vessels. Operating a large fleet comes large Operating Expenses (OPEX). In order to deliver a more cost-effective service, Boskalis turns to business intelligence (BI) to help with the decision-making process. Maintenance is crucial for the operation of the vessels, but also a large part of the expenses. Large deviations in maintenance costs and operational performance exist between the joint ventures. However, the reasons behind these deviations are yet unclear due to the absence of continuous monitoring capabilities. The objective is therefore to increase the management capabilities of detailed performance monitoring of M&R expenses and performance of tugs, through which possible improvements can be determined. The M&R of tugs is influenced by various factors, such as utilisation, operational location and installed equipment. This research has evaluated the current Enterprise Performance Management (EPM) of Boskalis Towage and used literature on Maintenance Performance Management (MPM) in order to erect a multi-criteria hierarchical function-specific framework which is a framework for maintenance performance monitoring. The presented framework covers aspects of alignment with business objectives and plan, strategy and implementation. Moreover, the framework presents the maintenance function and its areas of performance measuring of equipment-, cost- and process performance across the organisational hierarchy. By performing a regression analysis of the maintenance data, this has also resulted in an increased understanding of the relationship between maintenance costs, operational data and vessel characteristics. As a result, an equation with acceptable statistical accuracy for running repairs has been found. The implementing of the MPM framework on the maintenance of tugs has resulted in the MPM model. This model focuses on the running repairs and dry docking direct costs and activities, incorporating basic maintenance types, i.e. Preventive Maintenance (PM) and Corrective Maintenance (CM). Running repairs have been evaluated in the time domain while the evaluation of dry dockings have been evaluated as events due to their relationship with regulatory surveys. The model incorporates operational-, maintenance- and financial data, tug specifications and operational conditions in order to evaluate maintenance performance. Maintenance Performance Indicators (MPIs) have been established to determine deviations and deficiencies among the different aspects of M&R. Challenges were faced on the aspects of data quality and data management, especially in the areas of maintenance process. The model has been validated through a detailed evaluation of five selected tugs. The underlying reasons for the underperformance of these tugs have been found and verified with knowledgable bodies and thus validating the model and its ability to determine underperformance and deviations. An alternative performance analysis method, Data Envelopment Analysis (DEA), has been researched and shows promise. The Slack-Based Measure (SBM) DEA model is a non-parametric frontier approach, based on Linear Programming (LP), to evaluate performance based on slacks (room for improvement) of Decision Making Units (DMUs). The method is capable of determining similarities in inefficiency in maintenance performance, comparing it to results from the MPM model. It, therefore, proves the method is capable of quick evaluation of maintenance performance and of determining new maintenance targets. However, the model is simplistic and requires further detailing and is unable to determine underlying reasons for underperformance. The regression equation and DEA have been used to formulate a so-called performance region which describes the lower- and upper bounds of the running repair costs for individual tugs. Unfortunately, data quality doesn’t allow for the determining of these bounds for all vessels nor for dry docking. New key benchmarking targets have been established through quartile values for respective Maintenance Performance Indicators (MPIs). With this newly obtained knowledge, future maintenance performance evaluation of tugs can now be performed with a higher detail through analysis conducted with the developed MPM model.

In this thesis, it was examined how high-frequency operational data collected from an automated recording system, can be used to develop a vessel’s performance model. Both the traditional and the Machine Learning (ML) approach were examined. In the traditional approach, every component of the propulsion plant was examined separately, while empirical or semi-empirical methods were used for the added resistance due to waves, wind and shallow water. Historical data were used for verification and tuning (where needed) during the development of the model. In the Machine Learning approach, the method of Support Vector Machines was used. Also, it was examined whether a vessel’s performance model can be developed by combining the methods mentioned above. Thus, in total four models were developed. The data regarding the last year of operation of the vessel Schippersgracht were used (45000 data points) to test the models. It was found that with all the four models, 80 % of the examined dataset was calculated with an error of less than 10 %. The daily fuel consumption was calculated for the same dataset and for 90% of the days examined, the daily fuel consumption was calculated with an error of less than 10 %. The main conclusions about the developed performance models is that all the models resulted in more less the same accuracy. The model based on the traditional approach has the advantage that it offers more information and more outputs can be taken, compared to the ML approach which only provides the output of the fuel consumption. On the other hand, the model based on the ML approach is significantly faster and allows many iterations to be performed in a short time. Regarding the models which were developed by combining the approaches mentioned above, they did not result in additional advantages. Finally, two case studies were performed. In the first case study, it was presented how the model, developed following the traditional approach, can be used to examine how modifications in the propulsion system will influence the vessel’s fuel consumption. The case of switching from fixed rpm (that is currently used) to a variable rpm system was examined, which is a real scenario that the company is considering. It was calculated that installing the variable rpm system and a frequency converter will result in annual savings of around 250,000 € while the investment’s payback time is estimated to be around two years. In the second case study, a future voyage simulation algorithm was developed. This algorithm receives as inputs the voyage plan(route and speed) and performs a calculation for the voyage’s fuel consumption by taking into account the weather predictions. The voyage simulation algorithm is making use of the ML model. A few cases were examined in order to examine how many days in advance the calculation is reliable (due to the uncertainty of the weather predictions) and about the time interval that should be used in the algorithm. However, clear conclusions were not derived, and further examination is suggested(by examining more voyages).

One of the most important reasons to investigating fuel cells is the increased level of regulation regarding emissions in the maritime sector, while fuel cells offer the opportunity to reduce these emissions. It was not clear what the impact of these systems would be on a yacht, the aim of this project is therefore to gain more insight into these topics. The objective of this study was to investigate the impact on both the design and operation of a superyacht using fuel cells for energy supply on board. To reach this objective, first a review of different fuel cells and fuel technologies was executed. These conclusions are used to develop a decision making tool which will help in choosing between the different types of fuel and fuel cell techniques. Finally the tool is used to select the best possible fuel cell solution, for this option the impact on the design and operation of a fully fuel cell powered yacht is determined. The report is split up into two different parts, where in the first the technological review is carried out while the second part focused on the design study. In the first part a study was conducted into the status and characteristics of different fuel cell technologies and fuel storage solutions. Seven different types of fuel cells are investigated which can divided based on their operation temperatures (Low, Medium or High). Fourteen different types of fuels which are categorised as physical-, fuel- or material based hydrogen. The density of both separate systems were analysed and merged into a combined density for comparison reasons. Other factors which have been investigated are the: storage type, maturity, safety, and emissions. To be sure that a good choice can be made despite the many variables, these review subjects are used as decision criteria for the developed tool. In addition, the time influence on the density is taken into account by the adjustable time factor which is integrated in the tool. Specific preferences for a system can be given by changing the weighting factor for the different decision criteria. When changing the weight factors the order of all options will be rearranged by the tool, showing the ranking of the most promising solutions corresponding to the preferences of by the user. From this tool, it has become clear that a fuel cell solution should be specifically selected for any different type of application. A specific application could lead to the selection of a completely different type of technology, which is in contrast with a diesel combustion engine where only an appropriate size needs to be selected. The second part focuses on the design study of a fuel cell powered yacht, whereby an Oceanco yacht was used as reference. The most promising fuel cell solution for this yacht was selected based on the decision making tool and selected weighting criteria, a high temperature PEM fuel cell powered by methanol turned out to be the best solution. In order to determine the influence of the conversion to fuel cells additional research has been performed towards other factors which have an impact on the design. The following subjects were considered: regulations, fuel cell characteristics, energy storage, propulsion and electrical distribution. From these topics, several important conclusions have emerged. First of all the regulations have a substantial impact on the design of a yacht. Secondly, the fuel and fuel cells itself require more space compared to the original configuration, and the fuel cells require a larger battery system to be able to follow the fluctuating load of a yacht. Lastly, it became clear that the use of fuel cells makes it possible to have some volume and efficiency gains when switching to PODs and a DC energy distribution system. A detailed design study based on these findings made clear that the yacht needed to become longer to fit all the required systems while keeping the functional requirements for the owners the same. Additionally the system changes corresponding to the fuel cell conversion resulted in an increase in terms of weight. These changes in length and weight turned out to have negligible change on the resistance of the yacht. There are some factors which have an impact on the operation of the yacht. One of these is the fact that the lifespan of the used fuel cell technology is lower than that of a diesel combustion engine. A well designed hybrid system and by using shore power as much as possible, could be used to stretch the expected lifetime. Another operational issue could be the fact that this fuel cell technology is not fully developed which could influence the operability of the fuel cells. In addition, the methanol used as fuel is not as widely available as diesel. Positive influences are the fact that the overall efficiency increases while reducing all emissions with 100% except for the CO2 emissions which will be 14-20% lower compared to a diesel engine. When using green methanol, the overall emissions of the yacht will be completely reduced since it will be CO2 neutral. Additional advantages of fuel cells are the added comfort due to low noise and operation without any vibrations as well as an increased redundancy because of the modular design of the fuel cells.

The data-driven decision support system gives a competitive advantage by the cost-effective improvement of the fleet’s energy efficiency and by the controlled compliance with the IMO Greenhouse Gas Reduction Strategy. The conceptual Business Intelligence Design provides the foundation for data-driven decision support about energy efficiency for the entire Offshore Energy fleet. Boskalis Long Distance Towage department can cost-effectively improve their energy efficiency by 40% toward 2030 with respect to 2008 and thereby fully comply with the outlines of the IMO Greenhouse Gas Reduction Strategy. Boskalis offshore energy is recommanded to implement a Data-driven Decision Support System to manage the cost-effective energy efficiency improvement and the reduction of carbon emission. The organisational awareness and willingness to improve is a prerequisition for successful implementation.

The design of polar expedition cruise ship is not a trivial task to the naval architect due to the complex nature of the ship itself. Concept exploration are hereby required to improve the understanding of the design problem and identify its challenge as well as possible solutions. However, it is always difficult to generate the technically-feasible design solutions while still satisfying multiple and potentially conflicting performance criteria for the polar expedition cruise ship. There are currently two ways of optimizing the concept design: manual optimization and computer-optimization. The computer-based optimization, such as the Packing Approach developed by TU Delft, can semi-/automatically generate a set of design solutions. After the generation of these design solutions which are unknown in many performance behaviors, it is necessary to post-process them and increase the quality of those designs created from both optimization methods. Design rationale is an effective way to serve as qualitative metrics in post-processing the configuration layouts of the concept designs. However, the ambiguity and potential conflicting aspects within the design rationale are difficult to handle by the current post-processing method while fuzzy logic theory can be utilized to cope with the design problems involving subjective and ambiguity. Hence, it is proposed to develop a new methodology to better post-process the concept design of a polar expedition cruise ship.

This thesis presents the potential of solar energy to answer the increasing demand for sustainable energy. Multiple floating solar parks are installed on inland water bodies. This trend is a result of the lack of surface for PV systems and a result of legislation on national and international governmental levels, for the reduction of greenhouse gasses. This inland technology is currently well established. Still, in densely populated areas such as the Netherlands supplementary surface could be beneficial to unlock the full potential of solar energy. Ocean and sea surfaces are a possible, but challenging solution to this problem. These offshore water surfaces could be used for electricity or synthetic fuel production. Offshore locations are attractive because of the abundant availability of surface. Still, an OFPV-system needs to overcome multiple technical and non-technical challenges and requirements. This challenge demands technical solution within the constraints of a suitable business case. Furthermore, the impact on people and ecology also needs to stay within ethical borders. An OFPV can be subdivided into three physical subsystems: an energy converting system, a position monitoring or mooring system and a floating support structure. Multiple concepts were proposed in literature or by the industry. All proposed concepts are variations of support systems that provide a surface for conventional PV-technology. It also was concluded that none of the proposed concepts is fully developed. Currently, only one system is in the testing phase. The current state of the technology, and the high potential of an OFPV are the drivers behind the search for a new concept design. In this thesis, the requirements for an OFPV support structure were formulated, and a brainstorm resulted in the buoy and beam concept for further research. The buoy and beam structure is a system in which submerged beams form a triangle grid are held together by floating buoys. The buoys support triangle platforms, by carrying the corners of the platforms. All connections between the buoys, beams and platforms are fully hinged. Because of the hinges, the structure can move with the waves and therefore mitigates the loads it experiences. In the second part of this thesis, the feasibility of the buoy and beam structure was assessed. It was concluded that the heave response is the most critical response to the feasibility of the concept. When the platform would heave too much, the waves will slam into the platforms and the solar panels, leading to damage and excessive loads on the structure. Consequently, the heave response and the relative wave height seen from the moving triangle platform are researches and modelled. The structure was identified as a hydrodynamic transparent structure. Consequently, the relevant hydrodynamic loads are obtained with the Morison equation and Airy wave theory. All damping terms are linearised. A differential equation incorporated the constrains for both, the construction and the hydromechanic loads. The mechanical equations can be linearised by assuming small angular displacements of the beams. This differential equation is implemented in a calculation tool in MATLAB. The code is verified over multiple steps. The tool made it possible to obtain the response based on the topology and the main dimensions of the buoys and the beams. With this calculation tool relations between the dimensions of the buoys and beams on one side and the frequency response, on the other hand, are identified by simulating different variations of a simplified starting design. The following conclusions were made on the eigenfrequencies. Firstly, it was noted that the eigenfrequencies of the system are in proximity to each other. Secondly, it was shown that the first and second eigenfrequency could be calculated in a simplified manner. Thirdly, it was seen that the buoy diameter to mass ratio has a positive linear correlation with respect to the eigenfrequency, i.e. the stiffness to mass ratio of the system severely influences the eigenfrequency. Furthermore, it was seen that an increasing beam length has a slight linear correlation with the eigenfrequency. Also, it was concluded that a large hexagon system (for example, nineteen buoys) could be beneficial because a hexagon structure creates a large surface with respect to the number of buoys. Moreover, in reality, the response should be lower than the model prediction, as a result of the high number of beams that cause damping. Additionally, a hexagon system should have a minimal change in response for different incoming wave angle. To obtain a feasible system, the response peaks of the structure should not overlap with the wave spectrum. Based on the additional simulation, it was concluded that it should be possible to design a system with a low eigenfrequency resulting in a system that will only slightly move with the waves. Additional relations between the dimensions of the buoys and beams and the response peaks were found. The requirements to obtain a low eigenfrequency and a modest response match, which positively influences the feasibility. Some further steps on the research of the heave response and the relative wave height are needed. The calculation tool can still be improved. A preciser estimation of the response peaks is of significant importance. Some further iterations must be executed to determine the full potential and feasibility of the concept design. Furthermore, in a scientific point of view, it will be highly interesting to validate the model on a model scale. In the development of the buoy and beam structure, additional critical responses need to be researched. The forces in the hinges and the response in horizontal direction need to be known for further assessment of the feasibility. Next to the technical aspects, the human, ecological and economic implications of the buoy and beam structure need to be researched.

Yachts are built to provide guests with a unique experience. In order to provide this experience, yachts are often anchored at special locations. Captains prefer to use a single bow anchor when they moor the vessel. Problems are reported with respect to the availability while yachts are at anchor. These are caused by environmental forces. Availability is the yachting term for the operability of a yacht. The comfort on board and the availability of activities are the main aspects playing a role in the overall availability. Horizontal motions and accelerations of the vessel, respectively caused by wind and waves, are the main issues at anchor. These undesired accelerations can be reduced by controlling the yacht’s heading, ensuring optimal wave interaction. The objective of this research is to improve the availability while at anchor by suppressing the horizontal motions and controlling the heading of the vessel. Previous research suggests that using thrusters is a feasible solution for this. The research performed in this thesis provides a design proposition based on a quasi static analysis. For that reason, mathematical models are developed which are embedded in engineering tools. When these tools are defined, the first step is a parameter study. This has been performed to examine what, theoretically, is the preferred anchor support system. In this study, the required power and mooring force is calculated for a predefined capability. The capability is the environmental condition at which the system is able to be stationary. Based on the results can be concluded that the mooring line has to be located close to the pivot point of the vessel and that the thrusters have to be located with a large distance to the pivot point opposite to the mooring line location. Using multiple thrusters is often preferable because the same thrust can be delivered with less power. However, the thruster located the closest to the mooring line and pivot point delivers little thrust compared to the other thruster located further away. The usage of a tunnel thruster or an azimuth thruster is preferred. The difference between these two is limited because the azimuth thruster operates at an angle θ of 90 degrees. The theoretical solutions found neglect practical aspects which have to be taken into account for implementation; e.g. the layout of the vessel and the range of the required headings. To consider these aspects, multiple assessment criteria have been defined. The design study has been performed with various design cases. The capability of these cases has been calculated with the developed model in terms of wind speed. When the used power is reduced, the comfort with respect to noise is increased. However, this reduces the capability as well because less thrust can be delivered. The reduction of the capability is related to the power margin to the power 1/3, when the thrusters are operating at maximum allowable power. For each design case, the dynamic positioning capability has been calculated to investigate whether including a mooring line influences the capability. As a result of this research can be concluded that the capability of the anchor support systems is higher than the capability of the DP systems and that the anchor support system requires less power to do so. The DP system uses twice as much power for the required range of headings. The design proposition is determined based on the results of the quasi static calculations supported by a multi-criteria analysis. The preferred anchor support system for a yacht has an azimuth stern thruster in front of the platforms at the stern. Placing a thruster below these platforms causes safety issues and reduces the comfort. The yacht is equipped with an azimuth thruster in the bow because such a thruster can provide the same amount of thrust with less power and provides better controllability. The mooring line location is situated in the bow and is located on the centreline, thus an underwater anchor is required. The used approach and developed tools are provided to Feadship which allow them to consider the capability of anchor support system in the early design phase of the new yachts. This gives Feadship the opportunity to build yachts with a higher availability at anchor. As a result, the guests will be able to enjoy an even more unique experience due to the control of horizontal motions.

During the early stages of ship design exploration, design freedom is abundant but problem knowledge is scarce and most costs are already committed. This amounts to an incentive to look at the influences of the requirements on a design, to better understand how a concept is defined. This thesis investigates the operational architecture concerning how systems are used (often in a temporal fashion). A way to quantify the operational architecture is with operability, which describes the ability of a ship to perform its mission. This thesis identified the system performance consisting of availability and vulnerability part of operability as its main topic. Markov theory was selected to assess the availability of systems in order to maximize the operability of a naval vessel. Transition rates of systems are a key element of Markov theory but are hard to obtain during Early Stage Ship Design. A network-theory-based approach allocated nonquantifiable focus points to each system to determine their importance within a network. These were then linked to transition rates, which are required for a Markov chain to calculate the availability of a system. Four case studies were performed to test the model: several configurations were compared, two different focus points approaches were used, different ranges of rates were applied, and systems were added or subtracted. The model proved to behave according to educated guesses beforehand but also gave new insights in connections between nodes. The eigenvector centrality approach used to allocate focus points was found to be better than the combined connectivity approach. The scale of the ranges of rates should not result in very high values for system availability since they do not provide data which makes comparisons between network configurations possible. Very low values of system availability were deemed too far off from real-life values. This thesis paves the road towards a total assessment of operability. It has focused on the availability of systems, and delivered a method to make preliminary decisions for systems design in the early stages.

Traceability in complex ship design involves keeping track of the evolving relations between need, requirements and design. Such traceability is not fully developed in the current design process at DMO due to divisions in the design process and between design tools. This thesis proposes to use a single information model to facilitate traceability by connecting the need, requirements and design in a single database. Besides enabling traceability, such an information model can also be used to support modern modelling design tools. In the early design stage of naval vessels – the preliminary design phase – the capability, technical feasibility and affordability of a new ship are defined. Interactions between these three aspects are opaque and rely on the need for a new naval vessel and supporting requirements and preliminary design(s). Determining the need, requirements and design is in this thesis considered to be a ‘wicked problem’. In such problems, information gained by developing solutions helps define the problem itself. However, these solutions can only be determined with a certain interpretation of the initial problem. This results in many (evolving) interactions between the need, requirements and design in the ship design process as one is needed to define the other. With the help of Systems Engineering and Requirements Engineering information and relations in a ship design process can be determined and structured. These engineering fields are widely applied, and current technology enabled the development of computer aided approaches incorporating design theory, including computer aided traceability. One of the current developments in design approaches is the introduction of model-based approaches, which creates the possibility to actively manage more relations and interactions in the design process. Model based approaches such as the Design Structure Matrix are used to visualise relations between information, and Axiomatic Design enables the decomposition and creation of complex relations. A different approach to modelling in design processes is the use of Knowledge Based Engineering. Knowledge Based Engineering field aims to capture not only the relations and interactions between information in design processes, but also ‘knowledge’ about the ‘how’ and ‘why’ in these processes. Each of these model-based developments relies on, or enables, traceability of information. However, having a program capable of supporting an information storage to support these approaches remains difficult to achieve. For this purpose, Shipbuilder software was created to support transparent storage and management of information. In this thesis, theories for modelling approaches, Systems and Requirements Engineering and the DMO design process have been combined. This resulted in one information structure, applied in the Shipbuilder application, which enables traceability. To show that the proposed information model can model a ship and supports traceability, a case study has been performed. A small model of both an S- and L-frigate has been created to show how traceability can be performed in this information model.

Developments in the field of renewable energy technologies have lead to low energy cost in areas with specific characteristics. In the Middle East solar power plants are built for prices around 3 cent per kilowatt-hour and bids below 3 cent have been placed. In Europe wind energy is the second largest source of renewable energy after biomass. Although, wind farms are being built without subsidy the total cost of a wind farm is much higher in the order of 14 cent per kWh and it can decrease to 10 cent by 2030. In this research an concept study for the transport of electric energy is made to find an answer to the question: “is it possible to ship electric energy which is delivered in a port between areas of generation and consumption over a fixed distance with the use of a ship and deliver it for a levelised cost of electricity (LCoE) which is competitive in the market of unloading.” The cost of a kilowatt-hour of electric energy in the Dutch market is 8.33 if it is produced by a modern gas fired power plant and if the cost for CO2 emissions are included according to the current prices in the European emission trading scheme. If higher carbon cost scenario's are applied the price could increase to prices over 17 cent per kilowatt-hour. The concepts in this study are tested against four different carbon emission cost scenario's ranging from 8 euro/tCO2 to 190 euro/tCO2 Most electrical energy is transported by electric energy power grids. For long distance high volume energy transmission a high voltage direct current energy cable is the most efficient way to transport energy but at larger distances the transmission system gets more expensive. In this research the electric cable is used as a reference case which the concept has to outperform. To test the concepts a non-linear model is made which is solved with Matlab-integrated solvers to find the optimal transport concept. The model works by optimising the main dimensions of the ship. With this optimal ship design concepts are analysed. For this research: a concept based on a hydrogen-carrier (ammonia) and a concept based on thermal energy storage are discussed. . The hydrogen-carrier concept uses ammonia as a carrier. Ammonia has a high energy content and can be produced with the Haber Bosch process or with Solid State Ammonia Synthesis (SSAS). If the energy is produced using the well known Haber-Bosch process in 2018 the levelised cost of energy is 21.2 and 24.2 cent per kilowatt hour depending on the distance. Developments in the field of electrolysers will reduce the capital investment which can reduce the price to 17.8 to 20.8 cent per kilowatt hour by 2025 if the energy is supplied at 2 cent per kilowatt hour to the ammonia production facility. The SSAS method offers higher energy effincies at lower capital investment cost. The LCOE calculated in this research is 11.4 to 16.4 cent per kilowatt-hour. The thermal energy storage concept is based on molten salt. Molten salt is being used in concentrated solar power plants as a storage of energy. In the concept used in this project the molten salt is transported to another part where the heat which is stored in the salt is used to generate electricity. The LCoE is already 28.5 cent per kilowatt-hour at a distance of 1,000 nm. The thermal energy storage concept is more expensive than the ammonia concept. Depending on the distance and the carbon cost scenario's the concept can be competitive to the fixed connection with a cable and fossil fired power plants in the home market. If the low cost carbon scenario's (1 and 2) are applied by law makers the concept of electrical energy by sea is not competitive but if politicians would decide to increase the cost for carbon emissions the transport could become competitive. When the carbon emission cost increase to values over 100 euro/tCO2 the SSAS concept is competitive for distance up to 2,000 nm but it still more expensive than a cable connection. For this distances larger than 4,000 nm and carbon prices according to the 4th scenario (190 euro/tCO2) the SSAS-based concept can be a competitive energy supplier.

Autonomous sailing is considered by many to be the next big thing in the shipping sector. Many companies, including Rolls Royce and DNV are investing heavily in research that helps in the development of autonomous shipping. Most research is currently being done regarding autonomous navigation, communication and cyber security. What is often neglected in these studies is the need for maintenance within the engine room. With all ships having multiple crew members solely dedicated to keep the engine room going, their absence will have a big impact on the design of engine rooms. This paper aims to find what equipment will become a weak point in engine rooms once these are no longer occupied and maintained by crew members, and how these weak points can be eliminated. With the absence of reliability data that corrects for maintenance and crew interference, this paper tries to find these weak points by analysing crew member behaviour. It is assumed that if a crew members spends more time on equipment, or deals with it more frequently, then that piece of equipment is less reliable. In order to find what equipment can be seen as a weak point, a redundancy reduced risk index was created. This index is a combination of the frequency index, which states how often engineers spend time on equipment, the severity index, which lists the consequences of failure for equipment, and the redundancy index, which is dependent on the level of redundancy of components. The redundancy reduced risk index is split into three levels: low, medium, and high risk. Medium and high-risk components were considered weak points, while low risk components were not. For all high risk and for most medium risk components, solutions were generated which will reduce the risk index of the components or system overall. For some components, the risk was deemed acceptable, as any solutions would be too costly to justify the risk reduction. Solutions were split into two categories: specific solutions, which were all catered to specific components, and a bulk solution, which was the installation of a second drive train. A second drive train would include a second main engine, gearbox, propeller and rudder. With the solutions found, the two categories were subjected to a financial analysis to see if they are commercially viable. The solutions were applied to ships of four different sizes, ranging from a 6,000 GT feeder to an 85,000 GT capesize bulk carrier. For these ships, the OPEX were calculated and divided into four categories: Operational costs, fuel costs, capital costs and crew costs. The initial investment for the machinery plant was also calculated. This was the basis to finding the increased cost for solutions found in this paper. Using these specific solutions, the machinery plants will become roughly 50% more expensive, while adding a second drive train will increase the machinery cost by 110%. It is assumed that these solutions will eliminate the need for a crew and therefore eliminate all crew costs. Using these figures, it was found that the specific solutions will lead to a potential yearly savings of $600,000.– for all ship sizes, and adding a second drive train will lead to a potential yearly savings of $500,000 – for the small ship and $163,000.– for the larger ships. With both the specific solutions and the second drive train, the machinery plant is deemed reliable enough for continuously unmanned operation, which proves the technical feasibility of continuously unmanned engine rooms.

This study aims to develop a decision support tool which enables shipowners to select the most appropriate alternative fuel technology to comply with possible different imposed emission regulations while ensuring optimal business performance. In this context, most appropriate is defined as a fuel alternative which minimises required freight rate (RFR) while maximising overall performance on technological, environmental and other criteria. A decision support tool was devised combining a decision model based on the simple multi-attribute rating technique (SMART) with a financial model based on discounted cash-flow (DCF). Additionally, an optimisation model was implemented to optimise for minimal required freight rate through slow steaming. The decision tool provides shipowners with a quantified impact on their current business if they do not transition to alternative fuels under a 'market based measure' (MBM) regulatory scenario, as well as best-alternatives if their current fuels do not meet regulations under an 'emission cap' (EC) scenario. The decision tool is evaluated under optimistic, average and pessimistic scenarios in 2020, 2030 and 2050. Under an emission cap scenario, the results showed an overall preference for Fischer-Tropsch diesel (FTD) as the most promising alternative maritime fuel both in terms of SMART performance and required freight rate, followed by upgraded bio-oil (UBO). Nevertheless, the average difference in required freight rate of alternative fuels compared to HFO remains substantial, at 43% and 38% higher for Fischer-Tropsch diesel under a 'no regulation' scenario and 'market based measures' scenario, respectively. It is therefore evident that without regulatory intervention, heavy fuel oil is expected to retain dominance based on cost. Even under a market based measure (MBM) scenario, the average required freight rate of HFO increases only by 3.4% overall. For LNG, market-based measures lead to an average increase in RFR of 4.1%. These results suggest that in order for the maritime industry to transition towards sustainable alternative fuels, policymakers, governments, international organisations and lenders need to align their policies to collectively enable a more sustainable shipping industry - not only by enforcing stricter regulations, but also by providing the correct financial incentives.

The urgent development of green energy has become a worldwide trend in the war against the threat of global warming and the impact of extreme weather. The offshore wind farm is one of the solutions that are able to harvest energy sustainably from the environment. To erect these offshore windfarms, the debate about whether a new fleet should be designed and built or make the existed offshore fleet go under retrofitting has been raised. The stakeholder group involved in this issue is formed by the ship designers, ship operators, and market analysts. The difference between the existed offshore support vessel fleet and the offshore wind farm support fleet is the former is built to perform a certain operation and will require another considerable investment to be retrofitted while the latter is looking for solutions to switch from different equipment thus to keep the flexibility between different operation. The main objective of this research is to propose a ship design methodology to enable the offshore wind farm's request in mission flexibility by improving the design process in the preliminary design phase. Modularity and Knowledge Based Engineering (KBE) are chosen to be the two main topics to support the research objective. To narrow down the research scope, the research object is limited to a small Offshore support Vessel fleet that is able to perform service throughout the lifecycle of an offshore windfarm. The application of the modularity concept is to break down the vessel system into smaller subsystem or function blocks then reassemble them to be self-sufficient modules. Modules are the basic elements for forming a modular platform to provide a basic model that is able to perform various operations by mounting different equipment. In the former research done in NTNU, a methodology for manipulating the modularity to assemble a product platform by processing previous configuration scripts has been developed. It has greatly reduced the repetitive and iterative works in the design of similar vessels, especially the design for OSVs. Though the configuration scenarios are flexible to change, the pre-designed modules' properties are limited by the based configuration. On the other hand, the configurations are closely tight to the hull shape thus limited the freedom from both the hull design and configuration design. In this research, an improved configuration generator is developed to separate the configuration design and the hull design. The proposed methodology will also keep the flexibility in importing new configurations and the latest hull shapes without conflicts. Knowledge based engineering is another topic included in this research. It has been proved and widely used in the aerospace industry. As for the ship design industry, the application is limited to local structure design. KBE is a bridge to bring the user and the designer together in the design project. It consists of a programming stage, Knowledge Based System (KBS), to process the selection of suitable design cases and a visualization stage, Computer-Aided Design (CAD) ,to give a direct review on the whole design project. The fundamental drivers for each KBE system are called "High Level Primitive" (HLP). They are the basic units for the knowledge stored in the database. KBS picks out suitable HLPs from the database and assigned them in a configuration script thus forming a design result stored in the digital world. CAD will take over the result and visualize it in the drawing window. This is the proposed methodology to fill the gap between the modularity re-configuration and the diversity of modules. A Multi-Model-Generator (MMG) will become the final output of this research. It is designed to be able to reproduce several vessels in the OSV market. A further demonstration of the ability to generate a modular OSV product family at the end of the research. Though the modeling output has been proved to meet the index set for the research object, the MMG has the potential to be improved in the future by importing a well-constructed database from the industry.

Setting up or dismantling a shiprepair yard requires vast amounts of time and resources. Current shiprepair yards are land-based facilities that can not be moved when demand for their services declines. A mobile shiprepair facility would be able to and Damen Shiprepair & Conversion (DS&C) expressed interest to investigate the potential of a mobile shiprepair unit. When executed correctly, such a facility may reduce total repair time and thereby increase vessel availability through a higher shiprepair efficiency and reduction of travel time to the repair yard. The resulting competitive advantage can lead to profit maximization of DS&C.The goal of this thesis is to develop recommendations for DS&C regarding the feasibility of a mobile shiprepair facility. No facility of this kind exists to date, therefore the first step is to determine preliminary design features. The target market will be the mandatory intermediate and special surveys that a vessel is obliged to undergo every two and a half and five years respectively, requiring the vessels to undergo underwater investigations. A design feature following from that is the ability to haul vessels out of the water. The concept should moreover be sea-going, easy to (re)deploy and contain an all-round workshop and warehousing capabilities.Subsequently, the costs and projected revenues of the concept are identified and combined in a financial model. The cost items which differentiate a mobile yard from a traditional land-based shiprepair yard are: direct labour cost, machinery & installations cost, housing cost and travel expenses. Revenue results from shiprepair services and includes the quantified competitive advantage. The feasibility of a mobile shiprepair facility is then further evaluated in two case studies: the Caribbean sea and the west-coast of the African continent. The target market in the Caribbean are Supramax/Handymax size vessels and the target market in west-Africa is the support vessels for the offshore oil and gas sector. Both case studies evaluate a semi-submersible non-propelled facility that operates in a sheltered location.The Caribbean is the only area of the two case studies that shows potential. This can be explained by a higher efficiency and hence more projects that can be executed per year. Moreover, the same services can be sold for a higher price than on the west-coast of Africa. Several scenarios were identified in which the concept can be feasible on an annual base. However, the likeliness that these conditions persist during the projects lifetime is considered low and thus it is not recommended to deploy a mobile shiprepair facility in this area. Regarding the west-coast of Africa case study, even under the most favourable conditions - a very high occupational rate and an increase in target market conditions - it is not recommended to deploy a mobile shiprepair facility.It has been concluded using a stochastic sensitivity analysis that the duration of the maintenance project largely determines feasibility. The sensitivity to the fuel price, day rates of future clients and the reduction in deviation days were studied as well. All three were found not to be of large influence for the determination of feasibility, although it had been suspected differently for the last two. It has been found that the added value of the concept can not be transformed enough into a competitive advantage.If a change in conditions justifies the further development of this concept, this report provides several design criteria. Subsequently, recommendations are made on the design of a tool for the maximization of the reduction in deviation time of future clients to enhance the potential of the concept.

Solitaire is a DP positioned pipelay vessel capable of laying pipe up to 3000 meters. Currently, Solitaire is more than 40 years old. Although it has been upgraded multiple times, it has been identified that certain improvement can be achieved by retrofitting just the aft of the vessel. The purpose of the research is to evaluate the feasibility of improving Solitaire by retrofitting it with a new aftship, by exploring the different design possibilities, including the different stinger support configurations. To this end, an analysis of alternatives has been done and the preferred options have been implemented into a concept design. The use of Systems Engineering (SE) has been motivated by the need to establish a clear structure to guide the design due to the complexity of the problem. This methodology allows to keep a good overview of the requirements and constraints involved in the design. An operational analysis was carried out to identify the operational deficiencies of the design. This lead to four main areas of improvement. i.e, Longitudinal strength, Stinger and Stinger handling system (SHS), Resistance and Deck space. By addressing these operational deficiencies, the operational time of the vessel can be improved. Either by reducing the theoretical peak cycle time, decreasing the downtime or a combination of both. Based on the operational analysis a set of requirements has been compiled and a functional definition of the design has been made. With all the insight obtained through the operational analysis, the design requirements and the functional definition; an analysis of alternatives has been carried out. For each of the operational deficiencies, multiple alternatives are analysed. Local optima are found for each of the deficiencies although, if each of these local optima is implemented in the design, the global performance of the vessel is compromised. Therefore, a holistic design is proposed to integrate all the solutions into one preferred concept design. Overall, the findings of the research suggest that the retrofit of the aft is technically and economically feasible. Nevertheless, a design validation needs to be carried out to better quantify the total improvement of the new design.

From shallow to deep water, from the well to the ship, from the offshore field to shore or between countries, many kilometres of offshore pipelines for transportation of hydrocarbons (oil and gas) have been installed over the last decades. Allseas’ Tog Mor is a shallow water pipelay barge capable of laying pipes up to a water depth of 25 meters. Currently, Tog Mor is more than forty years old and is due for replacement. Therefore, Allseas has considered to replace Tog Mor with a new shallow water pipelay barge. However, it is unclear whether the current barge is optimised for pipelaying since it is designed for crane supported purposes. The aim of this research is to give insight into vessel properties which determine the pipelaying performances and to define a set of design requirements for the new shallow water pipelay barge, Tog Mor 2.0. To define the requirements of Tog Mor 2.0, the principles of Systems Engineering are followed. Based on the operational analysis, the performances of Tog Mor can be improved by a reduction of the theoretical peak cycle time, optimisations of the pipelaying process and a reduction of downtime. The output of the operational analysis in combination with the principles of pipelaying results in potential bottlenecks. Those performances and potential bottlenecks were the input of the functional definition of Systems Engineering. The aim of this functional definition is to allocate functions to systems and to prioritise the design focus point in terms of functions. Those functions were translated into hardware components and integrated in the total design. Due to the inversely proportional relationship of the number of production days and corresponding production costs, an increased number of stations and lay speed do not have an advantage in terms of costs. In order to reduce the theoretical peak cycle time, the specifications of the functional equipment are improved and the need of buoyancy modules is reduced. Less need of buoyancy modules is achieved by the increased capacity of the tensioner (two tensioners of 100 ton each) and an inner stinger. The pipelaying process is optimised by free deck space, a higher level of redundancy of the functional equipment and new technologies of equipment. The level of redundancy in combination with the improved workability results in a reduction of downtime. Those improvements results in a final concept design which proposes a barge with an off-centre firing-line of five stations (three welding stations, one testing & grit blasting station, one coating station). As a result of an improvement of each individual function and the interactions among those functions, an improvement of 30% in terms of theoretical minimum peak cycle is achieved by an optimisation of the pipelaying process and potential bottlenecks. A reduction of the peak cycle time, an optimised pipelaying process and a reduction of downtime percentages results in an improved overall performance of Tog Mor 2.0 compared to the current Tog Mor.