The electricity demand increases globally and requires a shift toward renewable sources to prevent the exhaustion of the planet. The shipping industry is responsible for 2-3 % of the global Greenhouse Gas emissions and Heerema Marine Contractors (HMC) identified floating solar as a promising solution to reduce the emissions, of their crane vessel Sleipnir, during operations. This study is the starting point of a technical feasibility study as a temporary energy supply for Sleipnir. The design is strongly focused on the temporary deployment and limited occupied deckspace during transit. Current floating solar systems are commonly designed for permanent deployment as supporting structure for rigid glass photovoltaic (PV) panels. Furthermore, modular constructions are used to limit the transportation costs however they are not designed for temporary deployment. A new PV innovation is flexible lightweight films which allow a more flexible supporting structure. A flexible thin sheet can be spooled on a drum to make temporary deployment possible. The influence of the wave loading on the coupled hydrodynamic behaviour is evaluated since wind and current loading are predictable based on previous research.

The structural design parameters of the thin sheet and drum are designed to mimic the excitation motion since wave structure interaction has been minimized to reduce the mooring force. Therefore, the draft must be low and the characteristic length related to the bending stiffness of the sheet should be smaller than the excitation wavelength. The draft of the drum should be low to have a natural heave frequency higher than the excitation frequency.

The coupled hydrodynamic response for head loading is evaluated with model tests in a towing tank. The concept is scaled according to Froude to ensure the surface waves, which are gravity-driven, are properly scaled. Regular waves are chosen based on the workability wave spectrum of Sleipnir. The roll and heave response over the frequency domain is indicated by analyzing the stable response at certain frequencies. The motions of the drum are obtained with the use of object tracking based on video recordings. The force within the connection of the system was measured with a force transducer whereas the mooring force was measured with a newly developed 3D-sensor.

It turns out that the heave motion of the system mimics the excitation motion over the wavelengths resulting in small drift forces. Significant rotations of the drum were observed for the longer wavelengths leading to water pumping over the sheet. The overturning moment is driven by the dynamic pressure over the drum diameter and the measured force in the connection generates a counteracting moment. The connection force is proportional to the buoyancy required to submerge the sheet and the acceleration of the free-floating sheet.

The feasibility of an OFPV concept for Sleipnir is demonstrated but the rotations have to be reduced by lowering the natural roll frequency. The drum dominates the coupled hydrodynamic behaviour compared to the sheet. Either the dimensions of the drum should be lowered or the thickness of the sheet must be increased. Decreasing the drum diameter is favourable over a thicker sheet since that would increase the characteristic length. Another option is to adjust the geometry of the drum to a shape where increased water displacement is required for the roll motion.

The International Maritime Organisation (IMO) has set the goal to reduce the total annual greenhouse gas emissions from international shipping by at least 50% by 2050 compared to 2008. For this reason, shipowners will have to innovate the drive-trains and energy systems of their vessels to reduce harmfull emissions. To achieve this goal, solutions must be found to store large amounts of cleen energy on board of ships and convert the chemical energy in an efficient way with these drive-trains. Hydrogen is considered as a promising solution for this. However, storing hydrogen is complicated and requires much volume. To overcome this barrier, hydrogen can be stored in dense hydrogen carriers (DHCs). This thesis will perform a technical and economical feasibility study of dense hydrogen carriers as a fuel to power a semi-submersible offshore crane vessel. The Sleipnir, the largest crane ship in the world, is the main subject of this thesis. The objective is to evaluate the technical and economic feasibility of hydrogen based fuels for semi-submersible offshore crane vessels and their impact on the drive-train design. This will be done by designing a new drive-train that can deliver 6.5MWelectricity to power the ship’s hotel load.

In this Master Thesis the potential of Additive Manufacturing on-board vessels of Heerema Marine Contractors is looked into, with the goal to design a recommendation for implementing this technology. Heerema is an offshore construction company that is intrinsically motivated to improve their sustainability. They transport, install and remove all types of offshore facilities. All Heerema vessels have a warehouse on-board, containing spare parts. Spare parts are parts in-stock that will be used to maintain the vessel or execute projects. In total the warehouse contains 300.000 parts, with an average value of 13.000.000 US$. The total weight of the stored material is 1.400.000 kg. If a needed spare part is not in-stock, it is ordered and brought to the vessel. Both actions take up a lot of time and could risk a project being stopped, which influences the economic pillar of the Triple Bottom Line consisting of people, planet and profit. Having this many parts on-board, and always ordering a ‘new part’ when something breaks, is not seen as a sustainable project execution. Especially taking into account the possibility of repairing. Next to that, extra transports or air freights are needed to get parts on-board, which influences the sustainable pillar of the Triple Bottom Line. In some cases, parts used to be produced by suppliers that do not exist anymore, which makes it hard to order new ones or obligated to purchase packages. The preferred situation for Heerema would be to use Additive Manufacturing as an additional production method for spare parts. For the implementation of this technology, a sufficient quality of the printed parts is desired. Sufficiency for critical parts has to be qualified by external certification organizations. Sufficiency for non-critical parts is reached once it functions within the used application. Next to the quality of the prints, the time it takes to print a part is important. Both quality and time depend on the performance of the 3D printer, which will influence the adoption of the crew. The preferred situation can be seen as the goal Heerema if aiming for. To reach this goal, a Roadmap is recommended. This Roadmap is designed as being the most suitable way of implementing and using 3D printing on-board of their vessels. The Roadmap is based on three different phases: The Research phase, The Printing phase and The Opportunities phase. Within these phases, the printing phase exists of two sub-phases: a plastic and a metal print phase. Each printing phase exists of a testing phase, a limited use phase and an expansion phase. The transition from one phase to another is based on a stepwise approach to lower the risks that could occur while implementing a complex innovation. The stepwise approach is based on the level of trust among the vessel crew towards the level of complexity of the implemented innovation. The conducted research supports the proposed solution that leads to the preferred situation. The solution is assessed according the three aspects of the Industrial Design Engineering domain: Technology, Human Values and Business.
The solution is shown to be feasible due to the chosen hardware, the study on printable spare parts, 3D print studies and mechanical tests at the TU Delft.
Additionally, the solution is shown to be viable due to relative low investment costs, a decrease in man-hours and transports and a waste reduction based on Value Stream Mapping. Also, the solution is shown to be desirable due to the collaboration with current users, a promising partnership with Layertec and the fit with the sustainability aims of Heerema. The thesis is enclosed by mentioning the research limitations, reflections, recommendations and further research for Heerema.