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Over the past few decades, wind energy has expanded to become a widespread, clean, and sustainable energy source. However, integrating offshore wind energy with the onshore AC grids presents many stability and control challenges that hinder the reliability and resilience of AC grids, particularly during faults. To address this issue, current grid codes require offshore wind farms (OWFs) to remain connected during and after faults. This requirement is challenging because, depending on the fault location and power flow direction, DC link over- or under-voltage can occur, potentially leading to the shutdown of converter stations. Therefore, this necessitates the proper understanding of key technical concepts associated with the integration of OWFs. To help fill the gap, this article performs an in-depth investigation of existing alternating current fault ride through (ACFRT) techniques of modular multilevel converter-based high-voltage direct current (MMC-HVDC) for OWFs. These techniques include the use of AC/DC choppers, flywheel energy storage devices (FESDs), power reduction strategies for OWFs, and energy optimization of the MMC. This article covers both scenarios of onshore and offshore AC faults. Given the importance of wind turbines (WTs) in transforming wind energy into mechanical energy, this article also presents an overview of four WT topologies. In addition, this article explores the advanced converter topologies employed in HVDC systems to transform three-phase AC voltages to DC voltages and vice versa at each terminal of the DC link. Finally, this article explores the key stability and control concepts, such as small signal stability and large disturbance stability, followed by future research trends in the development of converter topologies for HVDC transmission such as hybrid HVDC systems, which combine current source converters (CSCs) and voltage source converters (VSCs) and diode rectifier-based HVDC (DR-HVDC) systems. [ABSTRACT FROM AUTHOR]

In response to the global shift toward renewable energy, wind energy is a pivotal player in sustainability. Floating offshore wind turbines (FOWTs) emerge as a promising solution for expanding wind energy into economically challenging deep waters. Despite their potential, challenges persist, necessitating a thorough understanding of the complex coupling effects between wind turbine aerodynamics and hydrodynamics, particularly during the design phase. This study highlights this critical need and extends its scope to review the relevant existing literature. The paper provides insights into the design considerations and assessment methodologies crucial for both new structures and the evaluation of existing ones. Through modeling in the Ashes wind turbine software, the study reveals that platform surge motion significantly impacts rotor performance, causing rotor power and thrust fluctuations. By comparing various wind and sea states with baseline testing, the study underscores the necessity of coupling aerodynamic and hydrodynamic forces for accurate performance predictions. Besides, the paper offers actionable recommendations for designing and optimizing FOWTs, and sheds light on the challenges and opportunities within offshore wind energy, offering valuable guidance for engineers working toward sustainable energy solutions. [ABSTRACT FROM AUTHOR]

Measuring boundary layer stratification, wind shear, and turbulence remains challenging for wind resource assessment. In particular, larger eddy scales have the greatest impact on turbine load fluctuations, and there are few in situ methods to observe them adequately. Satellite remote sensing using synthetic aperture radar (SAR) is an alternative approach. In this study, eddy‐related signatures in 704 high‐resolution images are related to stratification through a bulk Richardson number (Ri$$ Ri $$) measured by a buoy near Martha's Vineyard, the US epicenter of offshore wind. Variations in SAR‐observed atmospheric boundary layer eddies, or lack of them, correspond to specific Ri$$ Ri $$ regimes. Accounting for strong vertical wind shear, typically under stable stratification, is critical for energy production and turbine loads, and SAR directly identifies these conditions by the absence of energetic eddies. SAR also provides a regional climatology of atmospheric stratification for offshore wind assessment, complementing other observations, and with potential application worldwide. [ABSTRACT FROM AUTHOR]

Global climate mitigation efforts seeking to reduce greenhouse gas emissions require more renewable energy generation and utilisation. In Aotearoa New Zealand there are initiatives underway to develop offshore wind, or in the future, arrays of tidal turbines or wave energy converters, as a new energy resource. Here we synthesise available knowledge from international developments in offshore windfarm installations and discuss in a local Aotearoa New Zealand context. Aspects described include habitat modification, consequences of physical water column changes, and effects on benthic organisms, fish and fisheries, seabirds and marine mammals. Importantly, there is a need to adhere to Te Tiriti o Waitangi which defines Māori sovereign rights and expectations in terms of guardianship of resources (kaitiakitanga). Based on recent regulatory applications in marine spatial planning, where developments have been subject to the precautionary principle for environmental impacts, comprehensive environmental information will be critical for obtaining approval to proceed. The present synthesis identifies environmental pressure-points, footprints, and knowledge gaps, such as New Zealand-specific seabird and marine mammal behaviour and discusses potential opportunities to leverage the positive impacts of marine renewable energy developments. [ABSTRACT FROM AUTHOR]

Numerical prediction of the interactions between wind and ocean waves is essential for climate modeling and a wide range of offshore operations. Large Eddy Simulation (LES) of the marine atmospheric boundary layer is a practical numerical predictive tool but requires parameterization of surface fluxes at the air–water interface. Current momentum flux parameterizations primarily use wave-phase adapting computational grids, incurring high computational costs, or use an equilibrium model based on Monin–Obukhov similarity theory for rough surfaces that cannot resolve wave phase information. To include wave phase-resolving physics at a cost similar to the equilibrium model, the MOving Surface Drag (MOSD) model is introduced. It assumes ideal airflow over locally piece-wise planar representations of moving water wave surfaces. Horizontally unresolved interactions are still modeled using the equilibrium model. Validation against experimental and numerical datasets with known monochromatic waves demonstrates the robustness and accuracy of the model in representing wave-induced impacts on mean velocity and Reynolds stress profiles. The model is formulated to be applicable to a broad range of wave fields and its ability to represent cross-swell and multiple wavelength cases is illustrated. Additionally, the model is applied to LES of a laboratory-scale fixed-bottom offshore wind turbine model, and the results are compared with wind tunnel experimental data. The LES with the MOSD model shows good agreement in wind–wave–wake interactions and phase-dependent physics at a low computational cost. The model's simplicity and minimal computational needs make it valuable for studying turbulent atmospheric-scale flows over the sea, particularly in offshore wind energy research. [ABSTRACT FROM AUTHOR]

This study comprises two essential components: a scoping review and interviews with fishermen, both aimed at understanding the Sustainable Development Goals (SDGs) and their relevance to Offshore Wind Energy (OWE) enterprises, particularly in mitigating impacts on local fisheries. Key findings from the scoping review indicate a scarcity of research explicitly dedicated to OWE enterprises' practices concerning. The review's findings emphasize the need for further research to understand the rationale behind these decisions and to explore how OWE enterprises can optimize their practices to address SDG 2. The second part of the study involves interviews with fishermen near proposed offshore wind farm sites in Taiwan. These interviews revealed that fishermen's primary concerns revolve around SDGs 2, 8, 14, and 17. However, OWE enterprises do not prioritize SDG 2, even though fishermen express concerns related to food security, proposing the adoption of marine ranching to enhance seafood supply. Moreover, SDG 17 stands out as a priority for fishermen, while OWE enterprises overlook connections with fisheries associations and fishermen. In conclusion, this study highlights the complexity of the SDG‐related issues surrounding OWE enterprises and their impact on local fisheries. [ABSTRACT FROM AUTHOR]

This research explores how participants in an innovation ecosystem, operating without a focal firm, can collaboratively envision and create societal value beyond their individual business goals. Using participatory action research, the investigation focuses on two cases within the offshore wind energy sector, involving four complementary enterprises and nine enterprises that are both complementary and competitive. The findings suggest that ecosystem participants can collectively pursue opportunities for sustainable value creation that surpass the interests and goals of individual firms. This shift towards a future-oriented, ecosystem-wide perspective was driven by the focus on ecosystem-level value propositions and the dynamic organizing of heterogeneous knowledge, individual behaviors, and organizational behaviors, enabling successful future-oriented sensemaking. The research process highlights practices that led to significant innovation outcomes, such as halving investments, reducing accidents and rework, accelerating operational flow, and fostering long-term investments, like a floating port for installation and maintenance improvements. This study enhances understanding of how future-oriented sensemaking in innovation ecosystems without a focal firm can drive innovation and societal value creation, offering insights for practitioners, academics, and policymakers on governance and collaborative efforts to enable value creation in innovation ecosystems. [ABSTRACT FROM AUTHOR]

Floating offshore wind (FOW) is rapidly gaining interest due to its large potential. In this regard, it is of special interest to determine the best locations for its installation. One of the main aspects when evaluating the feasibility of a project is the levelised cost of energy (LCOE), but there are many variables to consider when calculating it for FOW, and plenty of them are hard to find when the scope is all the suitable areas worldwide. This paper presents the calculation and analysis of the global LCOE with particular focus on the best countries and territories from an economic point of view, considering four types of platforms: semi-submersible, barge, spar, and tension leg platform (TLP). The model takes into account, on the one hand, wind data, average significant wave height, and distance to shore for an accurate calculation of delivered energy to the onshore substation and, on the other hand, bathymetry, distances, and existing data from projects to find appropriate functions for each cost with regression models (e.g., manufacturing, installation, operation and maintenance (O&M), and decommissioning costs). Its results can be used to assess the potential areas around the world and identify the countries and territories with the greatest opportunities regarding FOW. The lowest LCOE values, i.e., the optimal results, correspond to areas where wind resources are more abundant and the main variables of the site affecting the costs (water depth, average significant wave height, distance to shore, and distance to port) are as low as possible. These areas include the border between Venezuela and Colombia, the Canary Islands, Peru, the border between Western Sahara and Mauritania, Egypt, and the southernmost part of Argentina, with LCOEs around 90 €/MWh. Moreover, there are many areas in the range of 100–130 €/MWh. [ABSTRACT FROM AUTHOR]

ABSTRACT Measuring boundary layer stratification, wind shear, and turbulence remains challenging for wind resource assessment. In particular, larger eddy scales have the greatest impact on turbine load fluctuations, and there are few in situ methods to observe them adequately. Satellite remote sensing using synthetic aperture radar (SAR) is an alternative approach. In this study, eddy‐related signatures in 704 high‐resolution images are related to stratification through a bulk Richardson number ( Ri) measured by a buoy near Martha's Vineyard, the US epicenter of offshore wind. Variations in SAR‐observed atmospheric boundary layer eddies, or lack of them, correspond to specific Ri regimes. Accounting for strong vertical wind shear, typically under stable stratification, is critical for energy production and turbine loads, and SAR directly identifies these conditions by the absence of energetic eddies. SAR also provides a regional climatology of atmospheric stratification for offshore wind assessment, complementing other observations, and with potential application worldwide.

Floating offshore wind (FOW) is rapidly gaining interest due to its large potential. In this regard, it is of special interest to determine the best locations for its installation. One of the main aspects when evaluating the feasibility of a project is the levelised cost of energy (LCOE), but there are many variables to consider when calculating it for FOW, and plenty of them are hard to find when the scope is all the suitable areas worldwide. This paper presents the calculation and analysis of the global LCOE with particular focus on the best countries and territories from an economic point of view, considering four types of platforms: semi-submersible, barge, spar, and tension leg platform (TLP). The model takes into account, on the one hand, wind data, average significant wave height, and distance to shore for an accurate calculation of delivered energy to the onshore substation and, on the other hand, bathymetry, distances, and existing data from projects to find appropriate functions for each cost with regression models (e.g., manufacturing, installation, operation and maintenance (O&M), and decommissioning costs). Its results can be used to assess the potential areas around the world and identify the countries and territories with the greatest opportunities regarding FOW. The lowest LCOE values, i.e., the optimal results, correspond to areas where wind resources are more abundant and the main variables of the site affecting the costs (water depth, average significant wave height, distance to shore, and distance to port) are as low as possible. These areas include the border between Venezuela and Colombia, the Canary Islands, Peru, the border between Western Sahara and Mauritania, Egypt, and the southernmost part of Argentina, with LCOEs around 90 €/MWh. Moreover, there are many areas in the range of 100–130 €/MWh.

Abstract: Given the threat of fossil fuel depletion, it is essential to proactively strive for carbon neutrality and promote clean, low-carbon and efficient energy use. This study used ERA5 reanalysis data to assess wind energy resources in the Pacific Northwest region. By analyzing key indicators such as wind power density, effective wind speed occurrence, and energy level occurrence, climate statistics and Empirical Orthogonal Function analysis (EOF) were used to examine the spatial distribution and long-term trend of offshore wind energy resources in the Northwest Pacific. The results suggest that there are abundant wind energy resources in this region, which are beneficial for the development of offshore wind energy. The rich areas are the East China Sea, Taiwan islands and reefs in the South China Sea and east of Japan, with prevailing wind power density (500 ∼ 2500 W/m2) and effective wind speed occurrence (80–90%) and energy level occurrence (60% ∼ 90%). Offshore wind energy resources in the Pacific Northwest are more abundant in fall and winter than in summer. The time coefficient of the first mode shows that the offshore wind energy in the Northwest Pacific has no obvious change trend, and the wind energy resources are relatively stable.

Fuzzy multi-criteria decision making (FMCDM) is a critical field that addresses the inherent uncertainty and imprecision in complex decision scenarios. This study tackles the significant challenge of evaluating energy storage technologies (ESTs) in Vietnam's offshore wind sector, where traditional decision-making models often fall short due to their inability to handle fuzzy data and complex criteria interactions effectively. To overcome these limitations, the novel T-spherical fuzzy Einstein interaction operation matrix energy decision-making approach is introduced. This methodology integrates T-spherical fuzzy sets with matrix energy concepts and Einstein interaction operations, thereby eliminating the need for traditional aggregation processes and criteria weight determinations. My approach provides a structured evaluation of ESTs, highlighting that hydrogen storage, among others, demonstrates significant potential for high energy capacity and long-term storage. The findings not only underscore the robustness of this new method in managing the complexities of renewable energy assessment but also offer a comprehensive tool for selecting the most suitable ESTs to support Vietnam's energy transition strategies. This study recognizes limitations related to data dependency, which could affect the generalizability of the results. Future research is suggested to expand the ESTs considered and integrate extensive real-world operational data, aiming to deepen the exploration of economic impacts and long-term viability of these technologies. This revised approach emphasizes both the challenge of evaluating ESTs under uncertain conditions and my innovative solution, enhancing the relevance and applicability of the findings. [ABSTRACT FROM AUTHOR]

The global energy demand is increasing due to climate changes and carbon usages. Accumulating evidences showed energy sources using offshore wind from the sea can be added to increase our consumption capacity in long term. In addition, building offshore wind farms can also be environmentally advantageous compared to onshore farms. The assessment of wind energy resources is crucial for the site selection of wind farms. Currently, short-term wind forecast models have been developed to predict the wind power generation. However, methods are needed to improve the forecasting accuracy for ever-changing weather data. So, we try to use deep learning methods to predict long-term wind energy for identifying potential offshore wind farms. The experimental results indicate that PredRNN++ prediction model designed from the spatiotemporal perspective is feasible to evaluate long-term wind energy resources and has better performance than traditional LSTM. [ABSTRACT FROM AUTHOR]

Wind energy, which generates zero emissions, is an environmentally friendly alternative to conventional electricity generation. For this reason, wind energy is a very popular topic, and there are many studies on this subject. Previous studies have often focused on onshore or offshore installations, lacking comprehensive comparisons and often not accounting for technological advancements and their impact on cost and efficiency. This study addresses these gaps by comparing onshore and offshore wind turbines worldwide in terms of installed capacity, levelized cost of electricity (LCOE), total installed cost (TIC), capacity factor (CF), turbine capacity, hub height, and rotor diameter. Results show that onshore wind power capacity constituted 98.49% in 2010, 97.23% in 2015, and 92.9% in 2022 of the world's total cumulative installed wind power capacity. Offshore wind capacity has increased yearly due to advantages like stronger, more stable winds and easier installation of large turbine components. LCOE for onshore wind farms decreased from 0.1021 USD/kWh in 2010 to 0.0331 USD/kWh in 2021, while offshore LCOE decreased from 0.1879 USD/kWh in 2010 to 0.0752 USD/kWh in 2021. By 2050, wind energy will contribute to 35% of the global electricity production. This study overcomes previous limitations by providing a comprehensive and updated comparison that incorporates recent technological advancements and market trends to better inform future energy policies and investments. [ABSTRACT FROM AUTHOR]

Sri Lanka's energy issue is caused by underinvestment in renewable energy, resulting in rationing and power outages. Given its power output, offshore wind energy is a possible solution for a sustainable energy future. This study investigates the viability of an offshore wind farm by scrutinizing three potential sites, chosen based on wind speed, direction, and allied variables. Wind speed data from the ERA-5 repository and bathymetry information from the General Bathymetry Chart of Oceans support energy potential assessment for these locations. Employing the WAsP software, a technical analysis was performed to determine the energy output potential for water depths up to 50 m. Of the three sites, the western site emerged as the most productive, estimating an energy yield of 24.36 GWh from an 8 MW turbine. This calculation took into account a capacity utilization factor of 34.76%, with the levelized cost of energy approximating INR 7.70. The northern and southern sites trailed marginally, with estimated energy outputs of 20.31 GWh and 22.36 GWh, respectively. As evidenced by these findings, offshore wind energy holds promise as a dependable and steadfast energy source for Sri Lanka. It also highlights Sri Lanka's first offshore wind farm and future plans. [ABSTRACT FROM AUTHOR]

Offshore wind energy is characterized by its clean and renewable nature, leading to rapid growth in the industry. However, the incidence of ship collisions with offshore wind turbines has also risen with the increasing number of offshore wind farms, particularly in commercial shipping lanes. To gain a thorough understanding of dynamic response between wind turbines and vessels, this paper extensively reviews studies related to wind turbine–ship collisions over the past 2 decades to cover four key aspects: (i) the fundamental requirements and background of collision analysis study, (ii) the analysis of dynamic response and collision characteristics of the fixed-bottom and floating offshore wind turbines (OWTs) subjected to ship collision forces, (iii) the influence of key collision factors that include impact positions, initial ship kinetic energy, and soil–structure interaction on the structural response for the wind turbines, and (iv) a discussion of protection measures to mitigate the collision damage to the substructure. The limitations in the existing studies are discussed, and future research directions are suggested.

The environmental conditions of the ocean are rapidly deteriorating in many locations, largely due to anthropogenic activities. Previous studies have indicated both negative and positive impacts on marine biodiversity during the construction and operation of OWFs, but the impacts of decommissioning remain largely unknown. Assessments of marine biodiversity impacts are now needed to support science-based decisions as the first OWFs are approaching decommissioning. Life Cycle Impact Assessment (LCIA) offers a quantitative and transparent approach to impact assessment but does currently not adequately cover marine biodiversity impacts. As a first step in developing an LCIA method, we conducted a systematic literature review to identify the links between offshore infrastructure decommissioning activities and their impacts on marine biodiversity. Links were delineated as impact pathways, providing the foundational framework for future LCIA development. We extended the scope of our study to oil and gas (O&G) platforms, given the similarities between the two types of offshore infrastructure and decommissioning activities. Our study identifies numerous impact pathways through which OWF decommissioning affects marine biodiversity. We found many similarities between impacts from the decommissioning of OWFs and O&G, but generally, more pathways were identified for O&G decommissioning. As the structures resemble each other, this study suggests that much knowledge can be brought from O&G decommissioning to OWF. We identified habitat change as particularly important when investigating impacts associated with offshore decommissioning, as several pressures may affect habitat change. The study also identified implications for developing a comprehensive LCIA method, including a scarcity of quantitative studies and empirical data, baseline definitions, as well as inconsistency in biodiversity metrics applied across reviewed studies. Importantly, the identified impact pathways provide the first step toward integrating marine biodiversity into LCIA in the context of the decommissioning of offshore structures.

Offshore wind energy development (OWED), while a key strategy for reducing carbon emissions, has potential negative effects to wildlife that should be examined to inform decision making and adaptive management as the industry expands. We present a conceptual framework to guide the long-term study of potential effects to birds and bats from OWED. This framework includes a focus on exposure and vulnerability as key determinants of risk. For birds and bats that are exposed to OWED, there are three main effects of interest that may impact survival and productivity: 1) collision mortality, 2) behavioral responses, including avoidance, displacement, and attraction, and 3) habitat-mediated effects to prey populations. If these OWED effects cause changes in survival and/or breeding success (e.g., fitness), they have the potential for population-level consequences, including changes in population size and structure. Understanding the influence of ecological drivers on exposure and effect parameters can help to disentangle the potential impacts of OWED from other stressors. We use this theoretical framework to summarize existing relevant knowledge and identify current priority research questions (n=22) for the eastern United States, where largescale development of OWED is primarily in the planning and early construction phase. We also identify recommendations for study design and further prioritization of research topics. [ABSTRACT FROM AUTHOR]

Energy distribution justice is of primary concern within the energy justice framework and it is crucial to increase public acceptance of offshore wind energy and further advance its development. The rapid development of offshore wind energy in China has inevitably impacted the livelihoods of coastal vulnerable groups (CVGs) engaged in fisheries and tourism in the coastal zone. While current policies often compensate for livelihood losses through cash payments, the fiscal strain caused by COVID-19 renders this approach unsustainable. Consequently, this research pioneers the exploration of Chinese tourist groups' landscape preferences towards offshore wind farms (OWFs). This study proposes a new approach to enhance OWF landscapes for tourism development, thereby balancing the distribution of costs and benefits between CVGs and tourists. The research focuses on Beihai City in the Beibu Gulf Economic Region, utilizing a combination of Q-methodology and choice experiments that incorporates cut-offs. Answers to eighty Q-methodology questionnaires and 1324 choice experiment questionnaires are obtained. The findings indicate that this region can achieve energy distribution justice by compensating for the livelihood losses of CVGs through tourism. Contrary to traditional assumptions about wind farm noise preferences, Chinese tourists prefer proximity to OWFs, as an appropriate coastal acoustics landscape can enhance their tourism experience. In light of these findings, this paper presents policy recommendations towards energy distribution justice. [ABSTRACT FROM AUTHOR]

This comprehensive review explores the application and impact of digital twin (DT) technology in bolstering the reliability of Floating Offshore Wind Turbines (FOWTs) and their supporting platforms. Within the burgeoning domain of offshore wind energy, this study contextualises the need for heightened reliability measures in FOWTs and elucidates how DT technology serves as a transformative tool to address these concerns. Analysing the existing scholarly literature, the review encompasses insights into the historical reliability landscape, DT deployment methodologies, and their influence on FOWT structures. Findings underscore the pivotal role of DT technology in enhancing FOWT reliability through real-time monitoring and predictive maintenance strategies, resulting in improved operational efficiency and reduced downtime. Highlighting the significance of DT technology as a potent mechanism for fortifying FOWT reliability, the review emphasises its potential to foster a robust operational framework while acknowledging the necessity for continued research to address technical intricacies and regulatory considerations in its integration within offshore wind energy systems. Challenges and opportunities related to the integration of DT technology in FOWTs are thoroughly analysed, providing valuable insights into the role of DTs in optimising FOWT reliability and performance, thereby offering a foundation for future research and industry implementation. [ABSTRACT FROM AUTHOR]

Based on the mutual compensation of offshore wind energy and wave energy, a hybrid wind–wave power generation system can provide a highly cost-effective solution to the increasing demands for offshore power. To provide comprehensive guidance for future research, this study reviews the energy conversion and coupling technologies of existing hybrid Wind–wave power generation systems which have not been reported in previous publications. The working principles of various wind and wave energy conversion technologies are summarised in detail. In addition, existing energy coupling technologies are specifically classified and described. All aforementioned technologies are comprehensively compared and discussed. Technological gaps are highlighted, and future development forecasts are proposed. It is found that the integration of hydraulic wind turbines and oscillating wave energy converters is the most promising choice for hybrid wind–wave power extraction. DC and hydraulic coupling are expected to become mainstream energy coupling schemes in the future. Currently, the main technological gaps include short their operating life, low energy production, limited economic viability, and the scarcity of theoretical research and experimental tests. The field offers significant opportunities for expansion and innovation. [ABSTRACT FROM AUTHOR]

Foundation scour is the erosion of sediments around pile foundations by wave and current in offshore wind energy. This phenomenon destabilizes foundations and poses a threat to pile safety. Therefore, scour protection becomes a crucial challenge in offshore wind projects. This paper reviews and synthesizes recent publications and patented technologies related to scour protection. Considering the primary engineering concerns, the paper proposes design principles for effective scour protection schemes to standardize evaluation criteria. These principles prioritize efficacy, independence, and cost-efficiency, enabling the analysis of scour protection scheme applicability. In addition, this paper summarizes and describes common protection schemes in the literature. The effectiveness of their protection is analyzed and summarized, and their economic and performance independence is evaluated. This paper categorizes flow-altering scour protection schemes found in the literature. Based on a comprehensive understanding of the mechanisms and engineering requirements of scour protection, the paper proposes a focus on determining the erosion reduction rate curve ( E p − U / U c curve) as a key criterion for evaluating the effectiveness of protection schemes under varying flow velocities and the erosion reduction rate of scour protection schemes under extreme conditions. The study highlights the necessity of establishing a comprehensive design evaluation methodology, which is crucial for addressing the significant challenges related to scour encountered in offshore wind power projects. [ABSTRACT FROM AUTHOR]

Offshore wind farms are great options for addressing the world's energy and climate change challenges, as well as meeting rising energy demand while taking environmental and economic impacts into account. Floating wind turbines, in specific, depict the next horizon in the sustainable renewable energy industry. In this study, a life-cycle cost analysis for floating offshore wind turbines is developed by combining the most recent data and parametric formulas from databases and relevant papers. The cost analysis models focused on cost minimization with special emphasis on Operation and Maintenance Cost (OPEX), Decommissioning Cost (DECOM), and Levelized Cost of Energy (LCOE), which are important factors in wind power economy. Given that floating wind energy is still developing, the presented scenarios should be beneficial in making future decisions. The cost analysis scenarios include on-site and off-site maintenance scenarios for OPEX. In addition, four alternative scenarios for DECOM have been examined: mechanical recycling, mechanical-incineration, incineration processes, and landfill. According to the findings of these scenarios, OPEX varies from 16.89 to 19.93 £/MWh and DECOM between 3.47 and 3.65 £/MWh, whilst the total LCOE varied from 50.67 to 66.73 £/MWh. [ABSTRACT FROM AUTHOR]

This paper proposes a novel hybrid marine renewable energy-harvesting system to increase energy production, reduce levelized costs of energy and promote renewable marine energy. Firstly, various marine renewable energy resources and state-of-art technologies for energy exploitation and storage were reviewed. The site selection criteria for each energy-harvesting approach were identified, and a scoring matrix for site selection was proposed to screen suitable locations for the hybrid system. The Triton Knoll wind farm was used to demonstrate the effectiveness of the scoring matrix. An integrated energy system was designed, and FE modeling was performed to assess the effects of additional energy devices on the structural stability of the main wind turbine structure. It has been proven that the additional energy structures have a negligible influence on foundation/structure deflection (<1%) and increased system natural frequency by 6%; thus, they have a minimum influence on the original wind system but increased energy yield. [ABSTRACT FROM AUTHOR]

Identifying offshore wind energy sites involves analyzing multiple variables, such as wind speed, proximity to the coastline, and sociocultural factors. This complex decision-making process often involves many stakeholders, resulting in conflicting data and goals. Decision analysis that promotes collaboration, transparency, understanding, and sustainability is key. This study presents a unique model of human–environment interaction that reconciles different perspectives and visualizes the balance between fisheries and wind power. Using three multicriteria decision models (weighted aggregated sum product assessment [WASPAS], technique for order of preference by similarity to ideal solution [TOPSIS], and analytical hierarchy process [AHP]), we analyze the decision mix for wind farm selection and assess the impacts on fisheries using historical data. Our approach was applied to an upwelling system in California, generating ten tailored decision scenarios for different stakeholder groups. The results showed that adaptation scores for specific call areas in northern California decreased when the weight of fishery factors increased, and there was a tendency for high-scoring areas to shift southward as fishery parameters increased. The results of the sensitivity analysis showed that the first-order sensitivity scores of WASPAS were better correlated with the weights compared to TOPSIS, whereas the second-order sensitivity scores were generally lower, indicating a reduced interdependence of our model. [ABSTRACT FROM AUTHOR]

Offshore wind energy is a promising resource for renewable energy development. Reanalysed wind data are unmatched by other wind data sources in providing a long-term assessment of wind power potential. In this study, 10 of the selected offshore locations close to the Moroccan coast were used to evaluate the ERA5 wind reanalysis dataset against the IFREMER-blended observational dataset covering the years 1993–2016. The ERA5 wind data's capacity to represent wind variability in the area was confirmed by the results of the statistical methodologies used. All the reanalysed data scored better at capturing the observed wind variability at the southern sites than at the northern ones, where the wind variability was more complex. In a long-term evaluation from 1981 to 2020, the wind power potential in the Moroccan Atlantic coast was found to be very stable except in the northern sites and between Agadir and Bou Arich. Seven of the 10 sites considered were ranked as promising sites for offshore wind power generation, with wind power densities above 420 W/m2 at 100 m in height. Additionally, the change in signs in the variability toward the middle of the ERA5 record, which was seen at all locations and was also evident in the observations, did not significantly affect the yearly wind power density. However, the seasonal distribution of the latter was modified according to the local features of the seasonal variability. [ABSTRACT FROM AUTHOR]

Over the past few decades, wind energy has expanded to become a widespread, clean, and sustainable energy source. However, integrating offshore wind energy with the onshore AC grids presents many stability and control challenges that hinder the reliability and resilience of AC grids, particularly during faults. To address this issue, current grid codes require offshore wind farms (OWFs) to remain connected during and after faults. This requirement is challenging because, depending on the fault location and power flow direction, DC link over- or under-voltage can occur, potentially leading to the shutdown of converter stations. Therefore, this necessitates the proper understanding of key technical concepts associated with the integration of OWFs. To help fill the gap, this article performs an in-depth investigation of existing alternating current fault ride through (ACFRT) techniques of modular multilevel converter-based high-voltage direct current (MMC-HVDC) for OWFs. These techniques include the use of AC/DC choppers, flywheel energy storage devices (FESDs), power reduction strategies for OWFs, and energy optimization of the MMC. This article covers both scenarios of onshore and offshore AC faults. Given the importance of wind turbines (WTs) in transforming wind energy into mechanical energy, this article also presents an overview of four WT topologies. In addition, this article explores the advanced converter topologies employed in HVDC systems to transform three-phase AC voltages to DC voltages and vice versa at each terminal of the DC link. Finally, this article explores the key stability and control concepts, such as small signal stability and large disturbance stability, followed by future research trends in the development of converter topologies for HVDC transmission such as hybrid HVDC systems, which combine current source converters (CSCs) and voltage source converters (VSCs) and diode rectifier-based HVDC (DR-HVDC) systems.

This research explores how participants in an innovation ecosystem, operating without a focal firm, can collaboratively envision and create societal value beyond their individual business goals. Using participatory action research, the investigation focuses on two cases within the offshore wind energy sector, involving four complementary enterprises and nine enterprises that are both complementary and competitive. The findings suggest that ecosystem participants can collectively pursue opportunities for sustainable value creation that surpass the interests and goals of individual firms. This shift towards a future-oriented, ecosystem-wide perspective was driven by the focus on ecosystem-level value propositions and the dynamic organizing of heterogeneous knowledge, individual behaviors, and organizational behaviors, enabling successful future-oriented sensemaking. The research process highlights practices that led to significant innovation outcomes, such as halving investments, reducing accidents and rework, accelerating operational flow, and fostering long-term investments, like a floating port for installation and maintenance improvements. This study enhances understanding of how future-oriented sensemaking in innovation ecosystems without a focal firm can drive innovation and societal value creation, offering insights for practitioners, academics, and policymakers on governance and collaborative efforts to enable value creation in innovation ecosystems.

Despite the widespread usage of high-voltage alternating current (HVAC) for the connection of offshore wind farms (OWF), its use to power-from-shore (PFS) offshore oil and gas (O&G) production sites is often not feasible. Its limitations for long-distance subsea transmission are usually found at 50–70 km from shore and might be even shorter when compared commercially to a direct-current (DC) alternative or conventional generation. Therefore, this research paper aims to address the standardization of offshore transmission with a particular focus on the high-voltage direct current (HVDC) alternative. While the distance is typically not a limiting factor when using DC, and the voltages used are rather standard, the concept of power envelopes can be quite useful in addressing the high variability of offshore site power requirements and setting a design baseline that would lead to improved lead time. In this article, a full back and front-end genetic optioneering model purposely built from the ground up in Python language is used to #1 define up to three DC power envelopes that would cater to most of the candidate's requirements and #2 provide the lowest cost variance. The results will demonstrate that this can be achieved at a minor overall cost expense. [ABSTRACT FROM AUTHOR]

The government has set an ambitious target of renewable energy development in Malaysia. As a promising renewable energy source, wind energy plays an important role in the Malaysia renewable energy roadmap. Compared to onshore wind energy, offshore wind resources with better quality can be provided in the areas away from the coast, which has greater potential to contribute to electricity generation. Wind and bathymetry conditions are two important factors that determine the feasibility and economics of offshore wind turbines. In this paper, an investigation is conducted on wind and bathymetry conditions around Malaysia. The data source mainly originates from the Global Wind Atlas. The conditions of the coastal areas in different states and federal territories of both Peninsular Malaysia and East Malaysia are analysed, with a specific focus on wind speed, wind energy density, and bathymetry conditions in high-wind-speed regions. The data and survey are verified and compared with the past published literature. This paper aims to investigate the wind and bathymetry conditions around Malaysia, assess the potential of offshore wind energy, discuss the feasibility of offshore wind turbines, and provide references for offshore wind development in Malaysia. [ABSTRACT FROM AUTHOR]

Despite the promising outlook, the numerous economic and environmental benefits of offshore wind energy are still compromised by its high Operations and Maintenance (O&M) expenditures. On one hand, offshore-specific challenges such as site remoteness, harsh weather, transportation requirements, and production losses, significantly inflate the O&M costs relative to land-based wind farms. On the other hand, the uncertainties in weather conditions, asset degradation, and electricity prices largely constrain the farm operator's ability to identify the time windows at which maintenance is possible, let alone optimal. In response, we propose STOCHOS, short for the stochastic holistic opportunistic scheduler—a maintenance scheduling approach tailored to address the unique challenges and uncertainties in offshore wind farms. Given probabilistic forecasts of key environmental and operational parameters, STOCHOS optimally schedules the offshore maintenance tasks by harnessing the opportunities that arise due to favorable weather conditions, on-site maintenance resources, and maximal operating revenues. STOCHOS is formulated as a two-stage stochastic mixed-integer linear program, which we solve using a scenario-based rolling horizon algorithm that aligns with the industrial practice. Tested on real-world data from the U.S. North Atlantic where several offshore wind farms are in-development, STOCHOS demonstrates considerable improvements relative to prevalent maintenance benchmarks, across various O&M metrics, including total cost, downtime, resource utilization, and maintenance interruptions. [ABSTRACT FROM AUTHOR]

Morocco, a country without substantial fossil fuels, is emerging as a leader in renewable energy. This article addresses an untapped natural resource in Morocco: offshore wind. Methodologically, we use geographic information systems to assess optimal locations for offshore wind energy plants based on wind speed and power density from the Global Wind Atlas. We incorporate geological, environmental, and economic parameters and calculate capital expenses, operating expenses, development costs, and decommissioning costs to determine if the wind plant will provide a return on investment during its lifetime. The results identify three locations near the cities of Dakhla, Boujdour, and Essaouira that would recoup their investment in 14, 13, and 18 years, respectively, along with supplying 21.8% of Morocco's current energy needs for 2022. We conclude by considering the implications that the new plants would have for Morocco in the social, political, environmental, and economic dimensions. Integr Environ Assess Manag 2024;20:201–210. © 2023 SETAC Key Points: Morocco holds considerable potential in the form of offshore winds that are blowing by the north of Tangier, the Essaouira area, and the south of Morocco.A considerable investment of approximately $6 billion to build the designated power plants can cover more than 20% of Morocco's current power capacity in the long term.The socioeconomic aspect would be to reduce Morocco's energy trade deficit and provide job opportunities to the population, on the condition that local Morocco suppliers are preferred as much as possible, which can be done through long‐term investment.This study contains some limitations, and we hope that this research will act as a gateway to future exploration of this field, especially in Morocco. [ABSTRACT FROM AUTHOR]

Offshore wind energy production has seen a significant expansion in recent years. With technologies rapidly improving and prices dropping, it is now one of the key instruments in the green energy transition. The implications of offshore wind farm expansion for maritime security and ocean governance have, so far, received sparse attention in the literature. This article offers one of the first thorough analyses of the security of offshore wind farms and related installations, such as underwater electricity cables, energy islands, and hydrogen plants. The technical vulnerabilities of wind farm systems is reviewed and threats from terrorism, crime and State hostilities, including physical and cyber risk scenarios, are discussed. The expansion of green offshore energy production must keep pace with the changing threat landscape that follows from it. Prospective solutions for the protection of wind farms systems, including surveillance, patrols and self-protection are discussed. The current repertoire of maritime security solutions is in many ways capable of dealing with the threats and risks effectively if adjusted accordingly. The analysis builds important new bridges between debates in energy security and maritime security, as well as the implications of climate change adaption and mitigation for security at sea. [ABSTRACT FROM AUTHOR]

This article estimates the potential of using depleted offshore gas fields in Brazil for hydrogen storage and the effects this may have in terms of energy security. Brazil is starting to invest in producing green hydrogen associated with offshore wind energy generation. This initiative has stimulated the search for suitable locations to store hydrogen, including in depleted offshore gas reservoirs. The methodology used in this paper allows for identifying which of the 85 assessed depleted offshore gas fields are the most suitable for hydrogen storage and evaluating the storage capacity of the selected fields. In addition, a wind speed analysis is made to investigate possible locations for prospective wind energy generation projects that can accommodate green hydrogen production. As our main result, we find that the selected depleted offshore gas fields have the potential to store around 5483 TWh worth of hydrogen. This amount is equivalent to about 10 times the total annual electricity consumption in Brazil. Hence, Brazil can comfortably leverage its offshore wind potential in connection with hydrogen production to enhance the energy security of its electricity supply. Considering that to date primarily natural gas has been used as the main source of energy security in Brazil and that its share in the electricity sector has significantly increased over the last decade, the combination of hydrogen storage and renewable energy such as offshore wind power has the potential to provide a resilient and decarbonised electricity system in the country. Furthermore, hydrogen stored in offshore reservoirs in Brazil can become an important resource in the international energy market and constitute a possible key to energy security for countries to which Brazil may export hydrogen. We end our paper by providing comments on the challenges, opportunities, and prospects of offshore hydrogen storage in Brazil. • Offshore natural gas fields in Brazil are suitable for hydrogen storage. • Depleted offshore gas fields can store around 5483 TWh worth of hydrogen. • Two main offshore storage clusters exist in the Southeast and Northeast of Brazil. • Fossil fuel dependence in Brazil can be reduced through hydrogen use and storage. • Large-scale hydrogen storage can contribute to Brazil's energy security. [ABSTRACT FROM AUTHOR]

Direct air capture of carbon dioxide (CO 2) is technically a feasible solution for reducing atmospheric CO 2 concentrations at scale, building on decades of global research. However, powering such systems even partially with CO 2 -intensive fossil fuels results in more CO 2 emissions. This paper presents a novel energy management strategy (EMS) to further explore modular offshore wind energy off Canada's West Coast via power-to-direct air capture and power-to-gas systems. The system architecture includes a 15 MW wind turbine paired with a hydrogen energy storage system, i.e. hydrogen production and storage, and direct air capture (DAC) units. Hydrogen production from wind generation is stored and used to offer two key benefits: to deliver the thermal loads of the DAC system, and to meet hydrogen demand for external consumers. The proposed EMS offers an extra degree of freedom to operate the designed system by setting the priority either to maximize the amount of CO 2 capture or to maximize the amount of H 2 production for external consumers. In particular, the study incorporates dynamic mathematical modeling and constraints formulation for the aforementioned scenarios; DAC priority for CO 2 capture and H 2 for external hydrogen demand satisfaction. The effectiveness of the proposed EMS is shown through extensive simulations with different seasonal conditions. • Detailed mathematical dynamical models for offshore power-to-DAC and power-to-gas systems. • Green hydrogen production for two-fold benefits; H 2 for meeting DAC thermal loads, and H 2 as fuel for external consumers. • Scenario 1 prioritize the CO 2 capture rate, while scenario 2 maximizes the H 2 production for external consumers. • Design of EMS shows the correct unit commitment of the CO 2 capture rate and H 2 tracking. [ABSTRACT FROM AUTHOR]

The European Union's climate policy aims to reduce greenhouse gas emissions by 55% by 2030 and to achieve climate neutrality by 2050. One of the instruments for achieving these climate goals is the development of offshore wind energy. Unfortunately, Poland, as one of the few European Union countries with access to the sea, does not have offshore wind farms yet. The purpose of this article is to determine the importance of offshore wind energy for the development of Poland based on the example of two sea regions: the West Pomeranian and Pomeranian Voivodeships. This article uses the input–output method to determine the economic effects of offshore wind power. The region's share in the supply chain was determined based on the location of the offshore wind energy sector. A comparative analysis with the Saint-Brieuc offshore wind farm in France made it possible to show the differences between the studied locations. The supply chain share of the regions surveyed was 2.28% and 6.00% in the CAPEX phase and 5.98% and 8.23% in the OPEX phase. The annual average global value in the CAPEX phase at the country level was EUR 2793 million, and at the regional level, EUR 243 million and EUR 663 million. In the OPEX phase, the corresponding values are EUR 2106 million, EUR 223 million and EUR 663 million. The average annual employment in the CAPEX phase at the national level amounted to 26,323 jobs and at the regional level, 1953 and 5804. In the OPEX phase, employment amounted to 4790, 558 and 751 jobs, respectively. On the other hand, the average annual value added in the CAPEX phase at the national level was EUR 1221 million, and at the regional level, it was EUR 106 million and EUR 290 million. In the OPEX phase, it was EUR 920 million, EUR 97 million and EUR 239 million, respectively. While not all of the findings are conclusive, in general, the domestic offshore wind industry has weaker economic linkages and lower wage levels than the location adopted for comparison. It uses more labour-intensive economic sectors with lower OPEX value added. The results of the analyses presented in this paper are of crucial importance not only for Poland, as their advantage is the possibility to present, from an economic point of view, the profitability of this type of investment in general. [ABSTRACT FROM AUTHOR]

Information on marine mammals and marine birds in US Pacific Northwest waters is limited but necessary to assess potential impacts from proposed and planned human activity (for example, cable installation, energy and port development) as required by regulatory permitting processes, particularly relative to recent plans for offshore wind development. We conducted daily opportunistic, non-systematic observations of marine mammals and marine birds in autumn 2014 and of marine mammals in summer 2015 to meet mitigation and monitoring requirements associated with a geophysical site characterization survey for a proposed offshore wind floating platform demonstration project off Coos Bay, Oregon. Two biologists completed observations during daylight with the naked eye and reticle binoculars from a 17-m vessel between Coos Bay and the proposed platform site 30 km offshore. In 2014, 1058 h (3244 km) of observation occurred during 3 October through 4 November, with 1182 h (4367 km) observations conducted from 10 July through 28 August 2015. In total, 543 groups (approximately 1389 individuals) representing at least 14 marine mammal species and 7444 groups (approximately 18322 individuals) representing at least 22 marine bird species were observed. Sighting rates (number of individuals observed per 100 km of observation) were higher for nearly every species of marine mammal in summer 2015 than autumn 2014. An extralimital sighting of 25 Bottlenose Dolphins (Tursiops truncatus) and 5 sightings of rare transient Killer Whales (Orcinus orca) were documented. Results address a gap in site-specific marine mammal and marine bird baseline occurrence data and information required to assess effects of proposed offshore wind development and other human-related activities near Coos Bay, Oregon, as well as climate and oceanographic changes. [ABSTRACT FROM AUTHOR]