Offshore locations present significant amounts of wave energy and free sea space, which could facilitate the deployment of larger numbers of wave energy converters (WECs) in comparison with nearshore regions. The present study aims to find a suitable design for an offshore floating version of CECO, a sloped motion WEC. For this purpose, a new design methodology is proposed in this paper for identifying and assessing possible floating configurations of CECO, which consists of four distinct set-ups obtained by varying the type of main supporting structure and the mooring system. Two options are based on spar designs and the other two on tension leg platform (TLP) designs. Based on outcomes of time-domain numerical calculations, the aforementioned configurations were assessed in terms of annual wave energy conversion and magnitude of mooring loads. Results indicate that a TLP configuration with an innovative mooring solution could increase the annual energy production by 40% with respect to the fixed version of CECO. Besides, the mooring system is found to be a key component, influencing the overall system performance.

Absorbing wave power from oceans for producing a usable form of energy represents an attractive challenge, which for the most part concerns the development and integration, in a wave energy device, of a reliable, efficient and cost-effective power take-off mechanism. During the various stages of progress, for assessing a wave energy device, it is convenient to carry out experimental testing that, opportunely, takes into account the realistic behaviour of the power take-off mechanism at a small scale. To successfully replicate and assess the power take-off, good practices need to be implemented aiming to correctly scale and evaluate the power take-off mechanism and its behaviour. The present paper aims to explore and propose solutions that can be applied for reproducing and assessing the power take-off element during experimental studies, namely experimental set-ups enhancements, calibration practices, and error estimation methods. A series of recommendations on how to practically organize and carry out experiments were identified and three case studies are briefly covered. It was found that, despite specific options that can be strictly technology-dependent, various recommendations could be universally applicable.

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The offshore wind is the sector of marine renewable energy with the highest commercial development at present. The margin to optimise offshore wind foundations is considerable, thus attracting both the scientific and the industrial community. Due to the complexity of the marine environment, the foundation of an offshore wind turbine represents a considerable portion of the overall investment. An important part of the foundation’s costs relates to the scour protections, which prevent scour effects that can lead the structure to reach the ultimate and service limit states. Presently, the advances in scour protections design and its optimisation for marine environments face many challenges, and the latest findings are often bounded by stakeholder’s strict confidential policies. Therefore, this paper provides a broad overview of the latest improvements acquired on this topic, which would otherwise be difficult to obtain by the scientific and general professional community. In addition, this paper summarises the key challenges and recent advances related to offshore wind turbine scour protections. Knowledge gaps, recent findings and prospective research goals are critically analysed, including the study of potential synergies with other marine renewable energy technologies, as wave and tidal energy. This research shows that scour protections are a field of study quite challenging and still with numerous questions to be answered. Thus, optimisation of scour protections in the marine environment represents a meaningful opportunity to further increase the competitiveness of marine renewable energies.

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