Floating Offshore Wind Turbine (FOWT) is an innovative technology with little industry guidance for its hull design. Various FOWT floaters with different hull shapes claim to support the same turbines. Structural integrity and material expense analyses of different pontoon shapes were conducted, and it was found that some configurations, such as those with every two columns connected by both pontoon and bracing, have advantages over others. However, it is important to note that the choice of pontoon shape should be based on the wave loading conditions the floater will be exposed to. While a T-shaped pontoon provides a cost-effective solution under certain wave loading scenarios, it may not be the best option for all conditions. Specifically, ring pontoon designs with full bracing were found to be necessary for withstanding certain wave loads. Therefore, it is important to consider different Dominant Load Parameters (DLP) and ensure that a FOWT floater can withstand all applicable DLPs. An uneven hexahedral column shape, which combines the best attributes of square and round shapes, is proposed as a better alternative to cylindrical columns. It offers ease of manufacture and reasonably low drag. Bracing is found to be necessary for withstanding the wind turbine’s incurred moment and forces. The conclusion is that platform design should prioritize manufacturing costs and strength over maximizing hydrodynamic performance.

The few existing all-electric cargo ships were analysed. Their parameters and efficiency as profits were compared to fuel-powered vessels at different ranges and speeds. Electric ships were shown to be more profitable at short routes and less profitable on long routes. The reasons behind this result were explained and discussed. Some electric ships design guidelines were derived.

An Offshore Wind joint venture between Ukraine and Taiwan is proposed to exchange Ukrainian welding experience for Taiwan’s offshore wind technology, notably floating. The first Black Sea offshore wind farm is envisioned as the first economical driver of the project with later joint fixed and floating offshore wind turbine foundations production envisioned. The dangers and benefits of this project from technical and board socio-political aspects were analysed using the SPEED framework. As Ukraine and Taiwan governments are searching for possible post-war cooperation directions, this paper provides a promising idea in the field of Offshore Wind. The ultimate goal is to support the establishment of friendly relations between Taiwan and Ukraine.

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As wind energy developers start venturing into deeper waters with depths greater than 65 meters, the floating offshore wind turbines (FOWTs) are becoming the preferred solutions there over bottom-fixed structures. This paper summarizes the design of a semi-submersible platform for hosting a 15MW turbine. While semi-submersible origins from the oil & gas industry, the FOWT presents a different set of requisites and conditions for designing it. Recent existing and planned projects can be characterized by excessive use of steel and dimensions, compared to bottom-fixed structures. This paper aims to optimize the hull structure of a semi-submersible platform to be as cost-effective as possible while fulfilling the following design considerations: strength, vessel stability in still water and dynamic conditions, constructability, and operability. Meanwhile, the design is made to satisfy the rule requirements of major classification societies. Through a literature survey, data on existing semi-submersible projects is gathered and analyzed. The ratios of vessel displacement to hull steel weight relations are presented to show the trend. A high-level overview of class rules is given. An example platform, TaidaFloat, designed to carry a 15MW turbine is introduced. Its application is targeting a water depth from 65 to 100 meters with a deployment in Taiwan Strait in mind. The platform is designed against some limits and constraints, e.g. ensuring that it meets stability criteria. Its internal structural arrangement is preliminarily developed, and the steel weight is compared to recent projects. Features of the design are introduced, and their advantages are summarized.