The study uses a 35-year data set, which can be used to provide a long-term assessment for assessing wave power resources, availability for wave energy converters (WECs), and multithreshold accessibility suitable for numerous vessels and important for offshore maintenance operations. The data set demonstrates that winter months have harsher environmental conditions for the Western regions, such as the Spanish coastlines, and the Eastern regions, such as the Aegean Sea, record slightly higher waves during summer months. The data set also identifies the seasons with lower resources, which will have higher accessibility and will benefit offshore construction and maintenance operations for offshore energy activities. It has been shown that the availability for wave energy depends on the operational range of a particular type of WEC; hence, threshold selection affects the availability distribution more than accessibility. Availability varies per region, with Southern Aegean, Southern Italian, and North African coasts having higher monthly values. Accessibility in nearshore areas is constantly over 90%, with deeper waters presenting reduced levels. Statistical analysis performed for this work shows predictable availability due to lower maxima, potentially enhancing WECs operation; this, however, will depend on device properties. Furthermore, the resource analysis indicates that the dominantmetocean conditions yield low wave height range.

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Greece is a country that has numerous islands depending on conventional fossil fuels with electricity, fuel and transportation costs often subsidized by the State resulting in significant economic burdens. Small islands can benefit from adaptation of renewable energies to enhance their energy independence and promote sustainable development. In Greece majority of renewable sources utilized are wind and solar, however an un-tapped and under-investigated resource is wave energy. The wave resource encompasses higher energy density than wind and can contribute in the development of renewable energies, enhancing security of supply for smaller communities. Offshore locations offer significant advantages for renewable energy deployments with little interference on human activities and local ecosystems, hence reducing potential conflicts of interest and increasing social acceptance. Wind and wave resources differ in availability, in terms of energy production wind turbines can be estimated quite straightforward, on the other hand wave energy converters (WECs) require complex consideration and resource implication on energy production. Pending on regional focus different WECs are suitable, leading to different production profiles with WEC selection highly dependent on local long-term metocean condition. This study quantifies the temporal overlap by offshore wind and wave converters, in several locations around Greece using wind and wave data. Temporal overlap on energy production over long periods leads to robust results concerning the potential benefits by offshore devices.@en

Waves are characterised by high energy density content, able to provide significant renewable energy contribution. Identification of wave energy potential locations around Europe can provide significant benefits for application of wave energy converters (WECs). While the highest resources are placed in the open Atlantic coastlines of Europe that does not exclude the fact thatwave energy can provide significant contributions to the rest of Europe. To support such claims, a detail resource assessment has to be in place to characterize the resource. State of-the-art resource assessments provide a tool that can identify trends in the resource and proper evaluation of production, based on such long-term data allows robust financial and engineering decisions. In addition, the results can also be used for climate investigations, extreme value analysis, site characterization, and information concerning a variety of offshore activities. This study investigates the metocean conditions of the Mediterranean Sea and assesses the levels of energy around the Basin. Hidden opportunities lay in both energetic and milder wave environments with each having each own benefits and drawbacks, in terms of capital costs required and energy production. The results from the hindcast underwent a detailed annual, seasonal, and decadal analysis. Furthermore, potential benefits of wave energy converters (WECs), are assessed in terms of energy production, adaptability, and final considerations for site selection are discussed.@en