## 7 Discussion and Outlook  
In this section, the concept design from Section 6 is put into the context of the existing systems mentioned in Section 1.1. Based on this, the properties of the concept design and its limitations are discussed, and future steps required to develop the concept design further are pointed out.  
The concept design from Section 6 implements, such as the FARWIND energy ship and the proposed wind farm by the NIES, a kind of Beam Reach sailing strategy, as all designs are expected to reach their peak power when the wind comes from a beam. Another property that all proposals share is a catamaran-style floating platform. The concept design from Section 6 and the wind farm from the NIES use both primarily or only wind turbines to generate electricity [3]. The NIES concept incorporates 11 wind turbines [3] instead of one for the concept design. On the other hand, the FARWIND energy ship uses only hydrokinetic turbines to generate electricity. A hydrokinetic turbine is also intended to be implemented by the concept from Section 6, but not as the primary electricity generator. By comparing the sizes, the NIES proposal stands out with a length of around 2 km [3]. The concept design (74.3 m) and the FARWIND energy ship (31.7 m) [5] are on a much smaller scale. The same relationship holds for the electrical power output. The FARWIND energy ship with its two hydro turbines has a rated power of 1.8 MW [5], the concept design generates with its single wind turbine 4 MW (the electricity generated by the Propulsion Subsystem in generation mode--acting as a hydro turbine--is neglected), and the NIES wind farm 55 MW with its 11 wind turbines [3]. Concerning manoeuvrability, [PERSON] et al. [3] state that a turning operation takes a few hours. The FARWIND energy ship and the concept design are expected to be much more manoeuvrable, simply because they are much smaller. The FARWIND energy ship's manoeuvrability in operation is expected to be better than that of the concept design. The reason for this is seen in the Flettner rotors, which can be adjusted very fast to a new wind direction compared to the limiting rotational speed of the wind turbine rotor. The difference in manoeuvrability can not be quantified at the moment, nor can it be answered if the expected reduced manoeuvrability compared to the FARWIND energy ship is a measurable drawback for the capacity factor of the concept design. This might depend on the number of fast course changes during operation. The concept design is, compared to the other two designs, still in a very conceptual phase and introduces many new untested ideas, as is the aim of this study. The open question of how well these ideas would work in reality is, for example, applicable to the liquid hydrogen storage containers. Susiso Frontier, the world's first liquid hydrogen transport ship, entered service in 2020 [47]. The ship has a 1250 m\({}^{3}\) large vacuum-insulated liquid hydrogen storage tank [47]. It can not be said how well this technology can be adapted for the proposed storage containers. It also needs to be investigated in detail whether the Floatation Subsystem, with its smaller and larger buoyancy bodies, can provide sufficient stability even in extreme wave conditions. Further technical and economic studies are necessary to judge the suitability of the concept. For example, the sailing properties and energy performance, which are not explored at all and are just based on a conservative guess, can be investigated. All parts of the construction, being below or at the waterline, could be analysed in a CFD simulation. For this, in particular, the interaction with waves should be explored. It might also be important to simulate the concept design as a whole system to investigate the coupled dynamics and responses.