Fossil fuel consumption has progressively increased alongside global population growth, representing the predominant energy consumption pattern for humanity. Unfortunately, this persistent reliance on fossil fuels has resulted in a substantial surge in pollution emissions, exerting a detrimental influence on the delicate ecological balance. Therefore, it is imperative to find new renewable energy sources to replace fossil fuels. Solar energy is a clean energy source and has become the most preferred option for human day-to-day needs. Since the construction of the world’s first floating photovoltaic power station, humanity has been continuously advancing the technology of power generation by floating photovoltaics. This review comprehensively elucidates the progression of offshore photovoltaic technology and illustrates the composition of the floating photovoltaic system. Each section meticulously contrasts the advantages and drawbacks of various photovoltaic systems. In addition, an in-depth analysis of the offshore photovoltaic application potentials is conducted based on fundamental theories, thereby offering valuable insights for future research. Finally, an encompassing summary of the potential challenges associated with deep-sea floating photovoltaic systems is presented.

The installation and operation phases are critical stages in the lifecycle of offshore wind turbines, with costs associated with the installation and maintenance of floating wind turbines accounting for approximately 50% of the total investment. This paper presents the latest advancements in the technologies for the installation and maintenance of floating wind turbines. First, it discusses the installation techniques and relevant research related to the foundations and components of floating wind turbines. Next, it explores various operational strategies for offshore wind turbines and studies on major component replacements. The interrelationship of research in the installation and maintenance fields for floating wind turbines is examined. Furthermore, this paper investigates various tools and equipment used for the installation and maintenance of offshore wind turbines. It also addresses the relevant regulations and standards governing offshore operations for floating wind turbines. Finally, this paper provides a forward-looking perspective on the installation and maintenance of floating wind turbines.

Towing operation is an important part of the transportation and installation of offshore floating wind turbines. The study of towing resistance is of great significance to the efficient construction of floating wind turbine towing. This paper takes the floating wind turbine model designed by “China Energy Construction Group Guangdong Electric Power Design Institute Co., Ltd.” as the research object, uses STAR-CCM+ 2302 software to establish the computational domain model of floating wind turbine towing, and compares it with the existing physical model experimental results and empirical formula calculation results to verify the accuracy of the CFD resistance prediction method; then the method is used to calculate the still water towing resistance of the new large-megawatt floating wind turbine at different drafts and speeds, and according to the resistance calculation results, the integrated towing system of the floating wind turbine is established in ANSYS-AQWA (Version 2023 R1), the influence of environmental loads on towing resistance is analyzed, and the selection basis of tugboat is proposed. The results show that towing resistance is closely related to the draft, speed, and foundation configuration of the wind turbine platform. In order to ensure the safety of the towing system, the speed should be kept below 4 kn. The experimental results are compared and verified that the calculation results of this method are close to the experimental values and the empirical formula calculation values, which realizes the rapid prediction of the towing resistance of the floating wind turbine and provides guidance for the towing operation of the offshore floating wind turbine platform.

Accurate prediction of towing resistance is essential for selecting tug capacity and controlling energy demand during the wet-towing of floating offshore wind turbines (FOWTs). This study established a high-precision CFD numerical wave tank to simulate the towing hydrodynamic performance of the IEA-15 MW semi-submersible FOWT under calm water and regular wave conditions, covering two typical towing layouts (single-column-forward and double-column-forward) and three representative towing speeds. Based on CFD free-decay results, viscous damping corrections in heave, roll, and pitch were applied to the AQWA, while the drag coefficients were introduced through Morison elements. On this basis, an integrated viscous-potential flow coupled numerical model for the tugboat-FOWT system was then established. Frequency-domain analysis showed that wave excitation loads increase with towing speed under following-wave conditions, while the reverse trend occurs under head-wave conditions. Time-domain validation demonstrated that the viscosity-corrected potential flow model achieves a deviation below 2% for calm water resistance and less than 5% for mean wave resistance compared with high-fidelity CFD benchmarks. Parametric analysis under multiple regular wave conditions revealed that wave-added resistance first increases and then falls as wave period increases, consistent with the variation in surge wave excitation forces, and exhibits a nonlinear growth pattern with wave height. The double-column forward layout yields overall higher towing resistance than its single-column alternative, while main towline tension can accurately reflect the total towing resistance level. These technical outcomes provide actionable engineering guidance for low-carbon, cost-effective wet-towing scheme formulation, facilitating the sustainable, large-scale exploitation of deep-sea wind resources and advancing the long-term decarbonization of the marine energy sector.

Floating offshore wind turbines (FOWTs) constitute a pivotal offshore renewable energy technology, offering a sustainable and eco-friendly solution for large-scale marine power generation. Their low-carbon emission characteristics are highly aligned with global sustainable development goals, playing a crucial role in promoting energy structure transformation and reducing reliance on fossil fuels. This paper presents a numerical study on the coupled dynamic behavior of a semi-submersible FOWT during its mooring system installation. The proposed methodology incorporates environmental loads from incident waves, wind, and currents. Those forces act on not only the floating platform but also on the three tugboats employed throughout the installation procedure. Detailed evaluations of forces and motion responses are conducted across successive stages of the operation. The findings demonstrated the feasibility of the proposed mooring installation process for FOWTs while offering critical insights into suitable installation weather windows and motion responses of both the platform and tugboats. Furthermore, the novel installation scheme presented herein offers practical guidance for future engineering applications.