為達成2050年淨零碳排的目標並降低全球對化石燃料的依賴，再生能源的發展勢在必行。近年來，由於綠能技術進步快速，離岸風力發電成為最具競爭力及潛力的綠色能源之一，其中，因應國內當今對浮動式風電的規劃以及往較深水區域開發趨勢，本研究旨在建立浮式風機掛載之複合式繫纜系統關鍵技術。
本研究以半潛式浮動式平台搭載大型化15-MW風機作為模擬對象，並藉由ANSYS AQWA及Orcina OrcaFlex水動力數值分析軟體設計複合式繫纜系統。有別於傳統純鐵鍊之設計，複合式繫纜搭配不同合成纖維材料、及其於繫纜繩中分段配置進行彈性模擬，再加入整機系統以進行穩定性分析。合成纖維性價比高，常用於離岸再生能源裝置深水繫泊中，為檢視其於淺水海域中之效應與適應度，本研究選用風能密度較高之新竹外海及英國巴拉島西岸海域作為目標場址，兩者水深分別為100公尺及200公尺，透過模擬實際風場運作模式，以風機的動態耦合運動及繫纜繩張力呈現研究結果。
本文針對浮動式風機之極限限度狀態(ULS)及疲勞限度狀態(FLS)進行測試，以探討複合式繫纜系統之技術可行性、並加入繫纜繩成本估算，以利進一步的均化能源成本(LCOE)分析，其中，掛載複合式繫纜系統之浮動式風機均於50年回歸週期、極端海況條件(ESS)下通過相關規範。此外，為結合永續發展目標中海洋與海洋資源保育的實踐計畫，本研究亦著重於大型海洋哺乳動物群被繫纜繩纏繞危害的議題，以相對風險的型式在本文中做評估與說明。
綜整本文之研究，除浮台穩定性、複合式繫纜系統可行性及鯨豚纏繞風險評估外，亦考量浮式離岸風場海洋空間規劃改善方案，複合式繫纜系統的應用可大幅減少浮動式風機於海底床佔地範圍，進而實現海域空間優化的前景、亦可降低繫纜繩的設計成本。最後，本研究期望透過引進纏繞風險的量化方式提高現代工程對環境保護的重視，並為國內外離岸風電產業累積更全面且生態友善的經驗。

To achieve net-zero emissions by 2050, renewable energy is one of the innovative solutions to reduce people’s reliance on fossil fuels. Since technical progress in offshore wind has been rapid over the last few years, floating wind is now widely regarded as one of the most competitive approaches, which has a great potential in terms of electricity production.
The objective of this study is to develop a critical technology of hybrid mooring system in floating offshore wind. Synthetic fiber ropes offer considerable economic and operational advantages, which have been proved to be the most preferable candidates to substitute for traditional chains in deepwater offshore renewable energy (ORE) mooring configurations. Research of hybrid mooring which parts of mooring lines are replaced with fiber ropes is carried out in this study. Consequently, this study aims to analyze the different effectiveness of hybrid mooring system by comparison between shallower and deeper water region.
The scope of this study describes examinations of ultimate limit state (ULS) and fatigue limit state (FLS) requirements for technical feasibility, assessment of entanglement risk to marine mammals for biodiversity conservation, and cost estimation for levelized cost of energy (LCOE) in economics. First of all, a semi-submersible platform supporting a 15-MW wind turbine with hybrid mooring system is established, through integration of hydrodynamic numerical software, ANSYS AWQA, and then is imported into Orcina OrcaFlex to simulate coupled dynamic response over a time domain. To prioritize technical feasibility in engineering aspects, this turbine survives under extreme sea states (ESS), 50-year return period, with hybrid moorings in both shallow- and deep-water regions. Moreover, fatigue analysis is included to guarantee survivability under severe metocean conditions.
In addition, floating offshore wind farms require marine spatial planning to manage the utilization of oceans coherently. Recently, developments of wind energy have raised public concern about marine space optimization and their influence on natural environment and biodiversity conservation. It is crucial that FOWT adopts an efficient, safe, and sustainable strategy to exploit offshore wind resources. Therefore, this study assesses risk of marine megafauna entanglement hazard and improvement of ocean space optimization in hybrid moorings besides platform stability evaluation. Meanwhile, costs of hybrid mooring systems are analyzed and compared with pure chain design to highlight benefits of synthetic fiber ropes.

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