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Energy is the fundamental currency of the universe, driving the mechanisms of natural and artificial systems alike. From the molecular bonds in our bodies to the colossal fusion reactions within stars, every process hinges on the availability and ability of energy transmission. The capacity to harness energy has allowed human civilization to develop in the way we knowand understand it today. From harnessing fire to the construction of aqueducts to the monumental leap of the Industrial Revolution. These innovations are the essence of humanity’s historicalstrides in developing our current societies.However, just as every currency transaction incurs fees, our quest for energy comes at a cost. Our fossil fuel-powered world, while spurring unprecedented growth has also introduced not a few environmental costs.As we seek more efficient and sustainable ways to harness energy, we must recognize and address the challenges these solutions bring, balancing innovation with environmental stewardship.

To inform the sustainable development of offshore wind (OSW) in California, the California Marine Sanctuary Foundation (CMSF), a non-profit with 30 years of experience improving the resilience and stewardship of California’s coastal resources, is developing the Offshore Wind Environmental Monitoring Guidance (EMG) for the California Ocean Protection Council. In support of the EMG, this study reviewed scientific and gray literature and synthesized existing knowledge on fixed bottom and floating OSW’s impacts on marine ecosystems. The primary impacts on marine ecosystems include noise effects, displacement, entanglement and collision with, attraction to, or avoidance of OSW infrastructure, habitat alterations, anthropogenic emissions and pollution, and electromagnetic field (EMF) effects. Identifying knowledge gaps and monitoring priorities is critical for initial OSW development in California. This synthesis reveals that while we have a more developed understanding of OSW's acoustic and EMF impacts on marine megafauna, we lack a similarly complete understanding of OSW’s ecosystem-wide impacts on most taxa.

Anthropogenic stressors threaten large whales globally. Effective management requires an understanding of where, when, and why threats are occurring. Strandings data provide key information on geographic hotspots of risk and the relative importance of various threats. There is currently considerable public interest in the increased frequency of large whale strandings occurring along the US East Coast of the United States since 2016. Interest is accentuated due to a purported link with offshore wind energy development. We reviewed spatiotemporal patterns of strandings, mortalities, and serious injuries of humpback whales (Megaptera novaeangliae), the species most frequently involved, for which the US government has declared an "unusual mortality event" (UME). Our analysis highlights the role of vessel strikes, exacerbated by recent changes in humpback whale distribution and vessel traffic. Humpback whales have expanded into new foraging grounds in recent years. Mortalities due to vessel strikes have increased significantly in these newly occupied regions, which show high vessel traffic that also increased markedly during the UME. Surface feeding and feeding in shallow waters may have been contributing factors. We found no evidence that offshore wind development contributed to strandings or mortalities. This work highlights the need to consider behavioral, ecological, and anthropogenic factors to determine the drivers of mortality and serious injury in large whales and to provide informed guidance to decision‐makers. [ABSTRACT FROM AUTHOR]

Offshore wind has rapidly developed over the past three decades, with over 6000 fixed-bottom substructures installed in Europe alone as of 2022. Despite this progress, there has been limited focus on the end-of-life stages, particularly decommissioning, which is currently the default option. Sustainable offshore wind development hinges on effective decommissioning strategies for fixed-steel pile foundations. This review critically examines state-of-the-art pile-foundation-decommissioning methods recently tested in industry and academia, including partial-removal techniques like internal cutting and external cutting and full-removal approaches such as excavation and novel extraction methods. Key factors influencing decommissioning decisions, such as seabed disturbance, environmental impact, reuse potential, and cost, are discussed. Analyses reveal that current partial-removal strategies could render vast swaths of marine areas inaccessible for future development. In contrast, full removal through extraction may enable complete recycling and minimise post-decommissioning monitoring. However, significant knowledge gaps remain regarding novel extraction methods' scalability, technical feasibility, and economics. Extensive research encompassing engineering, environmental, and economic dimensions is essential to develop holistic pile-foundation-decommissioning solutions that facilitate the sustainable long-term growth of offshore wind. [ABSTRACT FROM AUTHOR]

Suction bucket jackets are increasingly being used to support bottom-fixed offshore wind turbines. It is generally assumed that contact between the underside of the bucket lid and the seabed is mandatory to safeguard against additional settlement. Lid contact is usually ensured by underwater grout injection, albeit this has a significant impact on the duration and costs of installation. Although grouting is routine, there are limited available data regarding the benefits of ensuring contact between the lid and the soil. This paper presents data from centrifuge tests of completely and partially installed buckets in dense sand subjected to vertical cyclic loading to investigate the role of lid contact. Lid contact was shown to have a discernible effect on displacement accumulation when buckets were loaded beyond the drained skirt capacity in compression. Under these conditions, settlement of a completely installed bucket was limited by lid contact with the soil plug, while partially installed buckets experienced continuous settlement, as expected. The physical evidence indicates complex load transfer mechanisms that are influenced significantly by the drainage conditions. Hence, an understanding of the soil drainage characteristics at a particular site would provide value when evaluating the requirement for under-lid grouting. [ABSTRACT FROM AUTHOR]

As offshore wind (OSW) energy expands globally, migratory songbirds are at risk of mortality from collisions with turbine blades, though the magnitude of this threat and which species are most vulnerable, remains poorly understood. Ecological vulnerability indices are commonly used to assess species' susceptibility to harmful factors, with results used to direct scarce research and monitoring resources to species showing relatively high vulnerability. These indices are based on the traits that elevate a species risk to adverse impacts (sensitivity), the overlap in occurrence between a species and the potentially harmful agent (exposure) and the influence of this exposure on the species' local or global persistence (resilience). We modified ecological vulnerability indices for seabirds to assess vulnerability of migratory songbirds to OSW related mortality. As a pertinent case study, we considered songbirds that fly across the Northwest Atlantic during their autumn migration. We utilized readily available information on each species' migratory behaviour, life history, and conservation status to calculate an index score that could range from 1 (lowest vulnerability) to 125 (highest vulnerability). We found scores of 3 to 55.2 for the 101 songbird species evaluated, with New World warblers (Parulidae) over‐represented among the highest scoring species. We found the scores to be sensitive to uncertainty in index components, highlighting the importance of considering scoring uncertainty when evaluating ecological vulnerability indices. Finally, we found that for seven of the top 10 highest scoring species, modest improvements in population trends had the potential to lower the scores substantially. Synthesis and applications. Our methodology is readily applicable to other regions where offshore wind (OSW) development is planned and songbird migration is common, allowing research and monitoring activities to be targeted to species most likely to be negatively affected by OSW facility encounters. [ABSTRACT FROM AUTHOR]

Suction bucket jackets have been used as foundations for offshore wind turbines in intermediate water depths where layered soil stratigraphies are often encountered. Although suction installation in layered soils has been studied, experimental data on the in-service response is scarce. During installation in stratigraphies containing a low permeability layer underlain by a high permeability layer, suction is transferred to the underlying layer when the pressure at the lid invert is sufficient to uplift the low permeability plug. This suction-transfer mechanism also affects the in-service response, albeit the load-sharing mechanism is not well understood. This paper presents data from centrifuge tests of suction buckets subjected to constant amplitude and varying amplitude cyclic vertical loading in two stratigraphies—a sand with an overlying clay layer and in a sand with a sandwiched clay layer. These experiments show that tensile stresses exceeding the vented tensile resistance can be withstood without significant uplift of the bucket in both stratigraphies, even under a zero mean stress. Plug uplift was shown to have an important effect on the amount of stress transferred to the skirts, with the load-sharing mechanism depending on the stratigraphy. Additionally, the load-sharing mechanism and the bucket in-service resistance was shown to depend on the effectiveness of the clay in sealing the soil plug within the bucket, with a more effective seal resulting in higher tensile resistance and therefore better performance. A limiting loading condition was not identified in the sand with a sandwiched clay layer, with the data indicating that the suction pressure to cause plug uplift during cyclic loading may be much higher than during suction installation. [ABSTRACT FROM AUTHOR]

Over recent years, the emergence of the offshore wind sector has spurred much interest in subsea cables. The predominant failure modes of subsea cables are associated with extreme environmental conditions. Wave-forcing during severe storms is less expected and causes more damage. A generalized multiphysics cable model is constructed to predict the movement, damage, and lifetime of subsea cables subject to dynamic wave and current action due to abrasion and corrosion. The present cable lifespan prediction model extended the previous tide-only model by considering the contribution of hydrodynamic forces by waves and the effect of wave and current incident angle relative to the cable. The predicted cable sliding distance at each section of the cable is combined with the Archard abrasion wear model and the corrosion model to predict the loss of cable protective layers and the resulting expected lifespan of the cable. The model is the first of its kind that can predict the spatial variation of wave and current loading, cable movement, damage, remaining lifetime, and cable failure modes and location. In addition, spatial and temporal variations of magnitude and direction of wave, current, and tide can be incorporated into the model for realistic large-scale simulations of cable performance in field conditions. The model compares well with previous laboratory experiments and numerical models. The present model was applied for the first time to the European Marine Energy Centre (EMEC)'s wave test site located at Billia Croo off the west coast of mainland Orkney, Scotland, and validated by the cable lifespan data. The 1-year and 100-year return period wave height and period and the average wave and tide conditions are used to drive the present cable lifespan model. It was found that the cable movement is predominantly driven by waves, and the previous tide-only model would predict zero cable movement, indicating the importance of the incorporation of wave contribution into the cable model. Furthermore, besides wave height and period, the wave angle relative to cable was found to be a determining factor for the cable movement and lifespan. The present multiphysics cable model provides a new capability to predict 70% of failure modes currently not monitored in situ and to deploy, plan, and manage subsea cables with improved fidelity, reduced cost, and human risk. [ABSTRACT FROM AUTHOR]

This research is the first application of Unmanned Aerial Vehicles (UAVs) equipped with Multi-access Edge Computing (MEC) servers to offshore wind farms, providing a new task offloading solution to address the challenge of scarce edge servers in offshore wind farms. The proposed strategy is to offload the computational tasks in this scenario to other MEC servers and compute them proportionally, which effectively reduces the computational pressure on local MEC servers when wind turbine data are abnormal. Finally, the task offloading problem is modeled as a multi-intelligent deep reinforcement learning problem, and a task offloading model based on Multi-Agent Deep Reinforcement Learning (MADRL) is established. The Adaptive Genetic Algorithm (AGA) is used to explore the action space of the Deep Deterministic Policy Gradient (DDPG), which effectively solves the problem of slow convergence of the DDPG algorithm in the high-dimensional action space. The simulation results show that the proposed algorithm, AGA-DDPG, saves approximately 61.8%, 55%, 21%, and 33% of the overall overhead compared to local MEC, random offloading, TD3, and DDPG, respectively. The proposed strategy is potentially important for improving real-time monitoring, big data analysis, and predictive maintenance of offshore wind farm operation and maintenance systems. [ABSTRACT FROM AUTHOR]

Installation refusal is a key design consideration for suction buckets. Pressure cycling, whereby the bucket is cycled vertically by reversing the pump flow, has been identified as one of the potential strategies to overcome installation challenges by reducing the required suction. This paper considers experimental data from centrifuge and field installations in sand and sand/clay layered soil profiles to examine the effectiveness of pressure cycling in different seabed conditions. The data indicate that cycling in sand only reduces the required suction pressure when this pressure remains lower than the critical suction and at depths at which frictional resistance is the dominant component of penetration resistance. Pressure cycling in layered soils is viewed as effective when the suction pressure remains lower than that required for plug uplift. The effect of pressure cycling on the required suction pressure is captured by a prediction model based on cone penetration test (CPT) data, and that includes a friction degradation term that is quantified from cyclic CPT data. The model is shown to provide reasonably good agreement with pressure-cycled suction bucket installations at both centrifuge and field scale. [ABSTRACT FROM AUTHOR]

AbstractA series of 3D finite element analyses were performed to examine the influence of loose sand layers on the monotonic lateral capacity of an extra-extra-large semirigid monopile in dense sand. The SANISAND-04 advanced constitutive model, which was meticulously calibrated, validated and verified using triaxial compression tests, centrifuge tests and a numerical study based on field tests, was adopted for this study. The impact of loose sand layers on monopile response is discussed in terms of its mode of deformation, critical lateral capacity, bending moment, shear force and soil resistance. Results show that the magnitude of the reduction in the monopile lateral capacity is dependent on the thickness and depth of the loose sand layer. Presence of loose sand at the tip of the monopile is also shown to have a significant effect on its lateral capacity. [ABSTRACT FROM AUTHOR]

Offshore wind has developed significantly over the past decade, and promising new markets are emerging, such as Brazil, South Africa, India, Poland, and Turkey. As logistic transport activities increase complexities, developing regional supply chains can help to reduce costs and enhance the sector's competitiveness. This article proposes a framework for the industrial development of the offshore wind supply chain in new markets. This study is grounded in a systematic literature review and is validated through a multi-case study, identifying key variables and factors influencing industrial growth. Adopting a process-based approach, factors and variables were modeled into a framework, encompassing the following four phases: (1) demand assessment of a new sector, (2) sectorial and industrial planning, (3) industrial development and maturity, and (4) sectorial and industrial renewal or decline. Each phase brings together a group of policies. Our findings show the policies' interrelations. These results complement the few studies that have examined the industrial development process, providing a clear guide as to the process for the development of the offshore wind industry in specific regions. Thus, the framework provides elements that contribute as a valuable tool to the debate, structuring, and development of public policies for the industrial development of a new sector. [ABSTRACT FROM AUTHOR]

In recent years, global efforts towards a future with sustainable energy have intensified the development of renewable energy sources (RESs) such as offshore wind, solar photovoltaics (PVs), hydro, and geothermal. Concurrently, green hydrogen, produced via water electrolysis using these RESs, has been recognized as a promising solution to decarbonizing traditionally hard-to-abate sectors. Furthermore, hydrogen storage provides a long-duration energy storage approach to managing the intermittency of RESs, which ensures a reliable and stable electricity supply and supports electric grid operations with ancillary services like frequency and voltage regulation. Despite significant progress, the hydrogen economy remains nascent, with ongoing developments and persistent uncertainties in economic, technological, and regulatory aspects. This paper provides a comprehensive review of the green hydrogen value chain, encompassing production, transportation logistics, storage methodologies, and end-use applications, while identifying key research gaps. Particular emphasis is placed on the integration of green hydrogen into both grid-connected and islanded systems, with a focus on operational strategies to enhance grid resilience and efficiency over both the long and short terms. Moreover, this paper draws on global case studies from pioneering green hydrogen projects to inform strategies that can accelerate the adoption and large-scale deployment of green hydrogen technologies across diverse sectors and geographies. [ABSTRACT FROM AUTHOR]

The availability of energy-bearing resources is a key determinant of the development strategy of the world's energy systems. In the case of Poland, the wind energy potential of the Baltic Sea provides the basis for the development of offshore wind energy in the country. The processes of transforming solutions towards green technologies require appropriate legislation, significant financial outlays, as well as public support for this dimension of activities. The latter strand requires continuous measurement to dynamically model the energy transition strategy. In the author's opinion, the available literature does not sufficiently explain this theme in relation to Polish conditions. Hence, it was considered reasonable to investigate the impact of offshore wind energy development in Poland on public opinion in a selected region of Poland, in order to diagnose the current scale of support for the changes taking place, and to identify the main expectations and fears related to this activity, which was assumed as the main objective of the study. The added value of the survey is the analysis of changes in public opinion over time. The methodology used for the research was a study of the scientific literature, with analysis of the results of own and secondary research conducted in Poland. In terms of in-depth research, statistical survey techniques supported by the PQstat programme were used. The results of the survey confirmed significant public support in the surveyed area for offshore wind energy development in Poland (68%). The overall percentage of support for offshore development increased by 5% y/y. Economic considerations for the support of the activities in question with the potential vision of lowering energy prices in the domestic market were confirmed with a result of 65%. It was further confirmed that a key aspect of support for the offshore development strategy in the surveyed region of Poland is the potential for development of the region in relation to offshore farm investments, with a focus on the labour market, with indications of 53% for both themes. Interestingly, there was no concern in relation to the risk of landscape change in an undesirable direction in 2024. [ABSTRACT FROM AUTHOR]

Expanding floating wind into new markets could support emission reduction targets in several national contexts. It furthers the need for adequate assessments to gain a full understanding of the technology's potential in future markets. South Africa is a prime case study as it has seen limited industry and policy developments despite its huge technical potential for floating offshore wind (FOW). This paper assessed the locational potential of floating wind in South Africa through a three-phased approach that evaluated the key technical drivers/barriers of the technology, conducted a Geographic Information System analysis (GIS) using ArcMap 10.8 to exclude unsuitable sites based on a predetermined exclusion criteria (including marine protected zones, underwater cables, major oil and gas deposits, etc.), and estimated the total harvestable capacity in the feasible sites. The study found that 2% (246,105.4 km2) of South Africa's entire Exclusive Economic Zone (EEZ) is suitable for hosting floating wind turbines, with a potential to generate a maximum of 142.61 GW of floating wind power. Although the Western Cape province holds the highest potential (80.52 GW) for floating wind in the country, the Eastern Cape region, with a locational potential of 20.04 GW, is considered most suitable for early-stage developments due to the availability of grid connection points, limited marine traffic, and proximity to appropriate port facilities. Future work can conduct techno-economic assessments to evaluate the technical and economic implications of developing floating wind in distinct sites in the country's EEZ. [ABSTRACT FROM AUTHOR]

Steel monopile support structures for offshore wind turbines require protection from corrosion and consideration with respect to biofouling on their external and internal surfaces. Cathodic protection (CP) works effectively to protect the external surfaces of monopiles, but internally, byproducts from aluminum sacrificial anode CP (SACP) and impressed current CP (ICCP) induce acidification that accelerates steel corrosion. Through an 8-week sea water deployment of four steel pipes, this project investigated the effect of perforations on internal CP systems. Additionally, marine growth on the internal and external surfaces of the pipes was assessed. SACP and ICCP systems inside perforated pipes performed similarly to external systems at a lower current demand relative to internal systems in sealed pipes. The organisms that grew inside of the perforated SACP and ICCP pipes were similar, suggesting that the CP systems did not affect organism recruitment. The results of this study demonstrate the potential benefits of designing perforated monopiles to enable corrosion control while providing an artificial reef structure for marine organisms to develop healthy ecosystems. [ABSTRACT FROM AUTHOR]

Low‐relief coastal landscapes are at major risk of rising sea levels, as vertical changes in relative sea level have far‐reaching lateral effects. Integration of a dense 2D grid of seismic reflection data with sedimentological and geotechnical data obtained in two offshore wind farm zones allows detailed documentation of postglacial landforms and environmental change over a 1,021 km2 area in the western sector of the southern North Sea. Following the retreat of Last Glacial Maximum ice sheets from the southern North Sea, the resulting postglacial terrestrial landscape provided a surface for peatland formation as climate started to warm and the water table rose in response to relative sea‐level rise. Southward‐draining fluvial networks formed contemporaneously with the peatlands, and remnants of this terrestrial wetland landscape are buried beneath Holocene marine sediments. Distinctive isolated incisional features and discrete widening of fluvial channels that cut through the peats are interpreted as either tidal ponds or relict tidal channels. These features record the evolution of this landscape through the Early Holocene as marine transgression inundated a low‐relief coastal plain. The erosion of the peatlands observed in the cores, the patchy preservation of the organic wetland landscape, and the lack of preserved barrier systems recorded by the seismic reflection data suggest that the rate of relative sea‐level rise outpaced sediment supply during the Late Postglacial and Early Holocene in this area of the southern North Sea. In a regional context, the southward draining river channels contrast to northward fluvial drainage to the North Sea, pointing to a subtle drainage divide in the palaeolandscape and the presence of a low‐relief land bridge separating the North Sea and the English‐Channel/La Manche during the Early Holocene. The documented scenario of rising sea levels combined with decreasing sediment supply in a low‐relief setting is a situation faced by many global deltas and coastlines, which makes the southern North Sea a crucial archive of coastal landscape change. [ABSTRACT FROM AUTHOR]

Scotland's staple global exports will soon include renewable offshore energy, so-called green energy. Already, Scotland produces more electricity than it currently needs. The future story is about connectivity and the transformation of the National Grid which directs electricity supplies into homes and businesses. Scotland's offshore renewables ambition has been significant in putting the nation in the green energy spotlight and attracting the attention of international investment groups. The concept of a Just Transition – creating tens of thousands of new local jobs and employment – requires a workforce to develop the skills to become productive members of this new sector. A Just Transition will require a great deal of fresh thinking, but too many Scots are unprepared for the change, and too few are set to truly benefit. Who will be the beneficiaries of this revolution? Only time will tell. [ABSTRACT FROM AUTHOR]

Green hydrogen is an important future energy source, which offers a vast potential to implement the decarbonization of the marine sector and advance broad shift to clean-energy alternatives globally. There are various advantages of offshore floating photovoltaics (FPVs) technology for hydrogen production; however, hydrogen storage in FPVs-based hydrogen production system faces several challenges. It is found that the major barrier concerning the system under investigation is related to safety. The current study aims to present an applicable offshore FPVs-based hydrogen production system, which involves both the FPV section and the hydrogen production section based on a project in China. A numerical 3D model is performed to investigate the characteristics of accidental damage through potential hydrogen storage device failure during system operation. The hydrogen release process of an FPVs-based hydrogen production system is presented with different offshore wind conditions, and the parameters for understanding the motion state and hydrogen release mode of hydrogen are also analyzed. The study further explores the dynamic development of hydrogen dispersion from a hydrogen production platform, including a momentum-dominated region, a horizontal spreading region, and a vertical buoyancy region. In addition, the influence of hydrogen explosive flame on thermal damage evaluation is illustrated, and thermal hazards under different offshore wind conditions are also discussed. The current study contributes to a better understanding of failure analysis of the FPVs–hydrogen production system and elaborates on damage evolution of hydrogen storage integrated with the system. The study also concentrates on marine environmental synergistic limits considering thermally damaged mechanical properties. [ABSTRACT FROM AUTHOR]

Offshore energy generation is one of the fastest-growing U.S. marine sectors, ranging from expanding deployment of offshore wind to rapid development and testing of technologies for energy conversion from waves, tides, ocean currents, and gradients in temperature, salinity, and pressure. Generating energy from the offshore environment creates expanded opportunities to improve upon the collection of ocean and coastal-derived data and information that will support economic and maritime growth, the management of resources, and solutions to address societal and climate issues. Despite its many promises and challenges, barriers remain for widespread implementation of offshore energy generation technologies that address the nation’s energy needs and climate change. A town hall was convened to present a vision of the changing ocean-scape through the lens of marine renewable technologies and to explore innovative solutions that these technologies might offer to support the New Blue Economy. [ABSTRACT FROM AUTHOR]

With increased focus on offshore wind (OSW) as a renewable energy resource in the United States and elsewhere, there are concerns about OSW impacts to wildlife, particularly birds and marine mammals. This study identifies technology gaps and technological research and development (R&D) priorities for monitoring marine mammals and birds for fixed and floating OSW. A synthesis of current monitoring technologies generated two databases (with over 100 technologies) that can be integrated in current technology repositories for renewable energy projects. Generally, the key technology R&D needs are similar for birds and marine mammals. The main exception is that some types of bird technologies are more likely to require direct integration with OSW infrastructure, whereas marine mammal systems tend to operate independently. Priorities to advance wildlife monitoring include improved early communication, harmonization of technologies and data collection for monitoring systems on OSW structures, battery/power access improvements, remote data transfer improvements, and advancements in automated collection and analysis of data. The successful integration of wildlife monitoring systems into OSW infrastructure and operations is dependent on remote access mechanisms for data collection, system maintenance, and data transfer, in order to minimize risks to worker safety in the offshore environment, as well as minimizing costs and disruption to normal operational activities. Application of the results of this study to prioritize and fund technology R&D will help to support statistically robust data collection and practicable integration of monitoring systems into OSW operations and infrastructure. [ABSTRACT FROM AUTHOR]

This study examines the current status and future potential of the offshore wind sector. Offshore wind is pivotal in transitioning to a low-carbon society and meeting rising energy demands, despite being capital-intensive. The industry aims to develop larger-scale wind farms in deeper ocean locations, with projections indicating significant cost reductions. To explore deeper ocean areas, specialized foundations like floating platforms moored to the seabed are required. This study proposes helical piles anchored in the seabed as a method to secure mooring lines. Using Plaxis 3D, a parametric examination was conducted on helical piles with two plates: one fixed at the pile's toe and the other varying in position between 0.5 and 13 m from the seabed surface. Load inclination angles (0, 20, 40, and 60 degrees) were used to simulate mooring line loads. Results indicate the optimal Zh/Z ratios for maintaining load-bearing capacity and stability: 0.12 (10 mm movements), 0.22 (25 mm), and 0.26 (50 mm) for small shaft diameters; and 0.34 (10 mm), 0.38 (25 mm), and 0.46 (50 mm) for large shaft diameters. These findings highlight the importance of specific load inclination angles based on shaft diameter and allowable movement for effective performance. [ABSTRACT FROM AUTHOR]

Offshore wind is nowadays already well developed in the North European countries. Ninety‐nine percent of the offshore wind turbines are installed on fixed foundations in shallow waters. For areas with water depth greater than 50–60 m, the floating wind is the cheapest and mostly used technology. This technology is going to reach the commercial phase in a few years, thus disclosing the potential of all marine areas with deep waters close to the coast, including the Mediterranean basin. One of the main challenges for floating offshore wind deployment in this area is the achievement of its economic feasibility. The offshore wind resource in the Mediterranean is generally lower than the one in the North Sea and in Oceans and the cost of offshore wind farms, especially with floating technology, is higher than the present offshore wind farm installations also because this industrial sector has not yet started in this area. However, in the Mediterranean area, the potential of offshore wind to contribute to the decarbonization pathway and reduce the dependence on imported fuel supply is substantial. Numerous studies, examined in this article, have already performed a technical‐economic assessment of offshore wind farms in different countries and geographical areas within the basin. A significant number of offshore wind projects are already in different stages of development, confirming the industrial interest and readiness of the Mediterranean offshore wind energy sector. The article provides a comprehensive review of various factors influencing the future deployment of offshore wind in the Mediterranean. It covers a range of topics including technology advancements, resource assessment, wind energy potential, ongoing projects, costs, and economic aspects. Additionally, it discusses environmental sustainability, regulatory frameworks, supply chain logistics, and system integration. The updated review presented in this article could assist decision‐makers and stakeholders in gaining a better understanding of the characteristics of this promising sector and accelerating its development. This article is categorized under:Sustainable Energy > Wind Energy [ABSTRACT FROM AUTHOR]

Given the rapid expansion of offshore wind development in the United States (US), the accurate mapping of benthic habitats, specifically surficial sediments, is essential for mitigating potential impacts on these valuable ecosystems. However, offshore wind development has outpaced results from environmental monitoring efforts, compelling stakeholders to rely on a limited set of public geospatial data for conducting impact assessments. The present study therefore sought to develop and evaluate a systematic workflow for generating regional-scale sediment maps using public geospatial data that may pose integration and modeling challenges. To demonstrate this approach, sediment distributions were characterized on the northeastern US continental shelf where offshore wind development has occurred since 2016. Publicly available sediment and bathymetric data in the region were processed using national classification standards and spatial tools, respectively, and integrated using a machine learning algorithm to predict sediment occurrence. Overall, this approach and the generated sediment composite effectively predicted sediment distributions in coastal areas but underperformed in offshore areas where data were either scarce or of poor quality. Despite these shortcomings, this study builds on benthic habitat mapping efforts and highlights the need for regional collaboration to standardize seafloor data collection and sharing activities for supporting offshore wind energy decisions. [ABSTRACT FROM AUTHOR]

This study evaluates the viability of WindPACT-1.5 MW Horizontal Axis Wind Turbine (HAWT) for offshore wind development in the shallow waters of Nigeria. With the imperative need to address escalating energy consumption and mitigate climate change impacts, offshore wind power holds promise, offering opportunities for substantial electricity generation and economic growth. In this study, key metrics were examined for three potential offshore electricity projects: Asabo, Forcados, and Bonny Offshores. Asabo Offshore demonstrated superior potential, projecting the highest electricity generation at 21,167,296.08 kWh, resulting in substantial revenue of ₦1,319,357,564.67 per annum. Moreover, its Levelized Cost of Electricity (LCOE) of ₦60.8184/kWh underscores its cost efficiency compared to Forcados and Bonny Offshore projects. Net profit analysis further revealed Asabo's positive financial returns, is very low and there are net losses for the other two sites. Notably, Asabo Offshore showcased a 2.49% Return on Investment (ROI), indicative of a very low profitability, while Forcados and Bonny Offshore indicated negative ROIs of -46.74% and -48.39%, signaling potential financial setbacks. This comprehensive evaluation demonstrates that the WindPACT-1.5 MW HAWT, does not hold significant promise for offshore wind development in Nigeria's shallow waters. [ABSTRACT FROM AUTHOR]

The coordinated development of offshore wind and electricity–hydrogen systems (OW-EHS) has the potential to enhance the utilization of renewable energy sources and achieve carbon neutrality. This article presents a case study of nine coastal provinces in China and designs four scenarios to analyze the economic benefits and potential hydrogen production capacity of OW-EHS. A multi-stage stochastic dual dynamic programming based approach is proposed for integrating OW-EHS, exploring offshore wind energy as both a primary electricity source for coastal regions and a clean, sustainable energy source for electrolyzers. It accounts for variations in hydrogen demand, wind uncertainty, load profiles, and electricity price dynamics, offering a holistic perspective on the feasibility and benefits of collaborative offshore wind and electricity–hydrogen systems. A comparative analysis highlights the effectiveness of the proposed planning approach, demonstrating its capacity to maximize the overall system benefits, encompassing both the optimal levelized cost of energy and hydrogen production. The new discoveries elucidate the unique attributes and advantages of each coastal province in OW-EHS. This research provides a tailored blueprint for coastal provinces in China to harness their offshore wind potential and accelerate progress towards carbon neutrality.

Negative emission technologies (NETs) are considered essential to keep global warming below 2 °C. Situating wind-powered carbon dioxide removal (CDR) devices offshore and injecting carbon dioxide (CO2) into deep-water sub-seafloor basalt aquifers has the potential to offer large CO2 removal capacity. It also avoids land and water-use competition and provides additional low-risk protections against post-injection leakage compared to terrestrial CO2 storage. This paper seeks to identify locations where offshore wind and potential basalt storage locations exist within close proximity to one another around the globe. A global mean wind power density map at 150 m height was computed using 30 years (1986–2016) of ERA5 hourly wind speed reanalysis data. Offshore regions with mean wind speed greater than 8 m/s were identified. Offshore regions with basalt aquifers along seismic or aseismic ridges which provide potential CO2 storage sites were identified and selected based on sediment thickness, age, and distance from plate boundaries. Four scenarios were constructed to capture a range of constraints with implications for technical, economic and regulatory difficulties. For each scenario, eligible regions for CO2 injection were filled by regularly spaced grid points and the distance to the nearest eligible wind resource was calculated for each point to identify the most promising configurations. Total available storage capacity within reach of wind resources was estimated to be between 4,300Gt and 196,000Gt depending on both uncertainties in porosity and other imposed constraints; even the most conservative estimates represent enormous capacity compared to global targets for negative emissions technologies. Typically, the best areas were found close to the poles due to the greater prevalence of good wind resources in those areas. Site-specific properties such as water depth and distance from shore are computed for the identified locations in order to characterize the conditions in which such locations are typically found.

Abstract Expanding floating wind into new markets could support emission reduction targets in several national contexts. It furthers the need for adequate assessments to gain a full understanding of the technology’s potential in future markets. South Africa is a prime case study as it has seen limited industry and policy developments despite its huge technical potential for floating offshore wind (FOW). This paper assessed the locational potential of floating wind in South Africa through a three-phased approach that evaluated the key technical drivers/barriers of the technology, conducted a Geographic Information System analysis (GIS) using ArcMap 10.8 to exclude unsuitable sites based on a predetermined exclusion criteria (including marine protected zones, underwater cables, major oil and gas deposits, etc.), and estimated the total harvestable capacity in the feasible sites. The study found that 2% (246,105.4 km2) of South Africa’s entire Exclusive Economic Zone (EEZ) is suitable for hosting floating wind turbines, with a potential to generate a maximum of 142.61 GW of floating wind power. Although the Western Cape province holds the highest potential (80.52 GW) for floating wind in the country, the Eastern Cape region, with a locational potential of 20.04 GW, is considered most suitable for early-stage developments due to the availability of grid connection points, limited marine traffic, and proximity to appropriate port facilities. Future work can conduct techno-economic assessments to evaluate the technical and economic implications of developing floating wind in distinct sites in the country’s EEZ.

This study investigates the environmental and financial implications of an offshore wind-driven green hydrogen generation system using Life Cycle Assessment (LCA) and Life Cycle Cost Analysis (LCCA) methodologies. Global Climate Models (GCM) are employed to predict wind speeds crucial for system efficacy, followed by sizing the electrolyser system based on projected offshore wind power output. As a result of this study, LCA utilizing the GREET 2023 reveals a Global Warming Potential (GWP) of 0.7 kgCO 2 -eq./kgH 2 and 0.753 kgCO 2 -eq./kgH 2 for GWP-20 and GWP-100, respectively. Fine Particulate Matter Formation (FPMF) is calculated as 0.24 gPM 2.5 /kgH 2 for FPMF-20 and 0.53 gPM 2.5 /kgH 2 for FPMF-100. In LCCA, under the base scenario, the Net Present Cost (NPC) and Levelized Cost of Hydrogen (LCOH) are estimated at $49.65 million and $4.36/kgH 2 , respectively. Despite various incentives and tax scenarios explored, it is revealed that Internal Rates of Return (IRRs) fall below the anticipated cost of equity, indicating non-profitability. • Environmental and economic evaluation of offshore wind-driven hydrogen production. • Among all components, the spar-buoy system is responsible for the highest GWPs. • GWPs of the electrolyser system are almost negligible compared to the wind turbine. • Hydrogen production from the proposed system is not feasible without any incentive. • IRRs fall below anticipated cost of equity; tax incentives crucial for profitability. [ABSTRACT FROM AUTHOR]

Introduction: The choice of which individuals and entities to include as sources in newspaper articles is an important decision for journalists, in large part because they can shape how readers understand the issue and which arguments become most salient. This is particularly important for issues that are relatively new or unknown to readers. The growing topic of offshore wind in the United States is a prime example of an issue that many people are encountering for the first time via media reporting. This issue has also proven to be highly divisive, with heated oppositional arguments being promoted by different entities. This study seeks to understand which entities are being represented in media coverage of offshore wind, and the different framing strategies that various entities use in quotes about the first two large-scale projects in the United States, South Fork Wind and Vineyard Wind I. Methods: We use a newspaper content analysis to identify and code the sources quoted in articles reporting on South Fork Wind and Vineyard Wind I from 2013- 2022, as well as the emphasis frames used by each entity. Results: We find that coverage varies in the two cases, but developers and political officials are quoted most frequently. As these entities tend to use frames highlighting the benefits of offshore wind more frequently than the risks, those perspectives dominate news coverage. Meanwhile, perspectives of community members and impacted industries such as the fishing industry are represented less frequently in news coverage. Discussion: These findings help explain the dominance of certain frames and perspectives in offshore wind, and they raise important questions about which voices are legitimized through representation in news media. [ABSTRACT FROM AUTHOR]

Green hydrogen production is a promising solution for the effective and economical exploitation of floating offshore wind energy in the far and deep sea. The inherent fluctuation and intermittency of wind power significantly challenge the comprehensive performance of the water electrolysis systems and hydrogen post-processing systems. Effective coordination with energy storage, including both electricity energy storage and hydrogen energy storage, can mitigate these challenges. Subsea energy storage is an emerging and promising alternative to conventional floating onboard energy storage. In this review, various potential subsea electricity and hydrogen energy storage solutions for 'floating offshore wind + hydrogen' are examined and compared. Many advantages, including security, energy efficiency, economy, lifecycle, and management, can be brought about if the energy storage systems are deployed at the seabed. In particular, integrating intermediate energy storage between the wind farm and hydrogen production plant will allow the expensive electrolyzers to be sized for a high utilization factor and reduce the degradation of electrolyzer performance. Recommendations are provided by analyzing the advantages and disadvantages of these energy storage options. Analysis of policy and market indicates that the period from 2024 to 2030 will be critical for the long-term competition of subsea energy storage with floating energy storage. Overall, subsea energy storage can be a promising enabler for emerging floating offshore wind hydrogen production. This review is intended to arouse extensive discussion and investigation on this topic. [Display omitted] • Energy storage is essential for producing green hydrogen from offshore wind. • Floating and subsea electricity and hydrogen energy storage are compared and discussed. • There is still no commercially acceptable energy storage solution. • The critical development period for subsea energy storage is from 2024 to 2030. [ABSTRACT FROM AUTHOR]

The marine environment faces continuous anthropogenic pressures, including infrastructural developments at a global scale. Integration of nature-inclusive measures in the design of infrastructural development is increasingly encouraged, but a lack of coordination results in fragmentation of projectbased measures, failing to meet the desired overall effects. To realize impact at system-scale, i.e. the seascape dimension required to achieve the set objective for a selected ecosystem component, overarching policies with shared targets towards effective nature-inclusive marine infrastructure are needed. We present a stepwise approach to work towards operational objectives for promoting selected ecosystem components that can be species, habitats or ecosystem processes, in which ruling policies, environmental conditions and the use of infrastructural development are aligned, and agreement on achievable ambitions is reached. Having clear targets will provide guidance to project developers in designing the infrastructure nature-inclusive, and in setting up relevant monitoring programs to evaluate the measures taken. We demonstrate how this stepwise approach could be applied to derive operational objectives for the design of nature-inclusive marine infrastructure in the context of offshore windfarm development in the North Sea, currently one of the most prominent infrastructure developments that changes the marine environment drastically. The European flat oyster Ostrea edulis has been selected as target species in the case study, as its once abundant population is now nearly extinct from the North Sea due to human disturbances, and there's growing interest to restore its reefs. The application of the stepwise approach indicates the potential for oyster reef restoration in the area, based upon a clear match between ruling policy, environmental conditions, and habitat suitability within offshore wind farms. An agreement between the main stakeholders on achievable ambitions can likely be established and would translate into the operational objective to actively introduce oysters to reach an initial critical mass and optimize settlement habitat in all future offshore wind farms in an area with suitable habitat characteristics. Such an agreement on overarching objectives is crucial to align separate initiatives to promote targeted ecosystem components and to jointly become most effective, which is ultimately in the best interest of the larger community using the system. [ABSTRACT FROM AUTHOR]

Low-cost green hydrogen production will be key in reaching net zero carbon emissions by 2050. Green hydrogen can be produced by electrolysis using renewable energy, including wind energy. However, the configuration of offshore wind-to-hydrogen systems is not yet standardised. For example, electrolysis can take place onshore or offshore. This work presents a framework to assess and quantify which configuration is more resilient, so that security of hydrogen supply is incorporated in strategic decisions with the following key findings. First, resilience should be assessed according to hydrogen supply, rather than hydrogen production. This allows the framework to be applicable for all identified system configurations. Second, resilience can be quantified according to the quantity, ratio, and lost revenue of the unsupplied hydrogen. [ABSTRACT FROM AUTHOR]

We investigated the predictive capability of various configurations of the Weather Research and Forecasting (WRF) model version 4.4, to predict hub height offshore wind speed and wind power density in the Northeast US wind farm lease areas. The selected atmospheric conditions were high-pressure systems (anticyclones) coinciding with wind speed below the cut-in wind turbine threshold. There are many factors affecting the potential of offshore wind power generation, one of them being low winds, namely wind droughts, that have been present in future climate change scenarios. The efficiency of high-resolution hub height wind prediction for such events has not been extensively investigated, even though the anticipation of such events will be important in our increased reliance on wind and solar power resources in the near future. We used offshore wind observations from the Woods Hole Oceanographic Institution's (WHOI) Air–Sea Interaction Tower (ASIT) located south of Martha's Vineyard to assess the impact of the initial and boundary conditions, number of model vertical levels, and inclusion of high-resolution sea surface temperature (SST) fields. Our focus has been on the influence of the initial and boundary conditions (ICBCs), SST, and model vertical layers. Our findings showed that the ICBCs exhibited the strongest influence on hub height wind predictions above all other factors. The NAM/WRF and HRRR/WRF were able to capture the decreased wind speed, and there was no single configuration that systematically produced better results. However, when using the predicted wind speed to estimate the wind power density, the HRRR/WRF had statistically improved results, with lower errors than the NAM/WRF. Our work underscored that for predicting offshore wind resources, it is important to evaluate not only the WRF predictive wind speed, but also the connection of wind speed to wind power. [ABSTRACT FROM AUTHOR]

Clean energy captured by offshore wind turbines has been widely used for supporting onshore activities. In the near future, facilities such as offshore wind turbines can also play an important role in the energy transition of offshore activities. Offshore wind energy can be employed for electrifying operations in offshore fish farms, which are traditionally supplied by diesel-engine barges/generators. Based on this motivation, this study focuses on the design of a shared mooring system between a semi-submersible offshore fish cage and a spar-type floating wind turbine. A numerical model of the proposed shared mooring system is implemented in a global response analysis software SIMA for performing fully coupled time-domain simulations. The configuration of the shared mooring line is determined using an engineering approach, which comprises Irvine's formulation, system eigenvalue analysis, and cost estimation. Moreover, relevant case studies by altering the environmental conditions are performed. Extreme operational conditions that may give large relative motions are investigated thoroughly. The dynamic performance of the integrated system is compared with that of individual structures. The global motion of the floating wind turbine and its mooring line's tension behavior are obviously influenced by the existence of the shared line. In general, the present work investigates the feasibility of a shared mooring system for these types of offshore structures and further gives insights into the engineering design procedure. [ABSTRACT FROM AUTHOR]

The tripod foundation (TF) is a prevalent foundation configuration in contemporary engineering practices. In comparison to a single pile, TF comprised interconnected individual piles, resulting in enhanced bearing capacity and stability. A physical model test was conducted within a sandy soil foundation, systematically varying the length-to-diameter ratio of the TF. The investigation aimed to comprehend the impact of altering the height of the central bucket on the historical horizontal bearing capacity of the foundation in saturated sand. Additionally, the study scrutinized the historical consequences of soil pressure and pore water pressure surrounding the bucket throughout the loading process. The historical findings revealed a significant enhancement in the horizontal bearing capacity of the TF under undrained conditions. When subjected to a historical horizontal loading angle of 0° for a single pile, the multi-bucket foundation exhibited superior historical bearing capacity compared to a single-pile foundation experiencing a historical loading angle of 180° under pulling conditions. With each historical increment in bucket height from 150 mm to 350 mm in 100 mm intervals, the historical horizontal bearing capacity of the TF exhibited an approximately 75% increase relative to the 150 mm bucket height, indicating a proportional relationship. Importantly, the historical internal pore water pressure within the bucket foundation remained unaffected by drainage conditions during loading. Conversely, undrained conditions led to a historical elevation in pore water pressure at the lower side of the pressure bucket. Consequently, in practical engineering applications, the optimization of the historical bearing efficacy of the TF necessitated the historical closure of the valve atop the foundation to sustain internal negative pressure within the bucket. This historical measure served to augment the historical horizontal bearing capacity. Simultaneously, historical external loads, such as wind, waves, and currents, were directed towards any individual bucket within the TF for optimal historical performance. [ABSTRACT FROM AUTHOR]

Offshore wind energy entering the grid in coastal areas creates issues with the safe and stable operation of power systems. To control the carbon emission of power systems and increase the proportion of offshore wind consumption, a microgrid optimization model considering offshore wind power and carbon trading is proposed in this paper. To avoid the defect of Particle Swarm Optimization (PSO) falling into the local optimum prematurely, the PSO algorithm is improved by dynamically decreasing inertia weights and chaos factors. Combined with the powerful optimization capability of the genetic algorithm (GA), the improved PSO-GA algorithm is used to solve the model. The simulation results show that the improved algorithm iterates 11 times before the parameters reach the optimal value, with high convergence accuracy. The proposed approach can increase the proportion of offshore wind consumption and ensure the optimal economic performance of the system while reducing the carbon emission. [ABSTRACT FROM AUTHOR]

In the oceanic surface layer, particulate organic carbon (POC) constitutes the biggest pool of particulate material of biological origin, encompassing phytoplankton, zooplankton, bacteria, and organic detritus. POC is of general interest in studies of biologically-mediated fluxes of carbon in the ocean, and over the years, several empirical algorithms have been proposed to retrieve POC concentrations from satellite products. These algorithms can be categorised into those that make use of remote-sensing-reflectance data directly, and those that are dependent on chlorophyll concentration and particle backscattering coefficient derived from reflectance values. In this study, a global database of in situ measurements of POC is assembled, against which these different types of algorithms are tested using daily matchup data extracted from the Ocean Colour Climate Change Initiative (OC-CCI; version 5). Through analyses of residuals, pixel-by-pixel uncertainties, and validation based on optical water types, areas for POC algorithm improvement are identified, particularly in regions underrepresented in the in situ POC data sets, such as coastal and high-latitude waters. We conclude that POC algorithms have reached a state of maturity and further improvements can be sought in blending algorithms for different optical water types when the required in situ data becomes available. The best performing band ratio algorithm was tuned to the OC-CCI version 5 product and used to produce a global time series of POC between 1997-2020 that is freely available. [ABSTRACT FROM AUTHOR]

Oceanic energy sources, notably offshore wind and wave power, present a significant opportunity to generate green hydrogen through water electrolysis. This approach allows for offshore hydrogen production, which can be efficiently transported through existing pipelines and stored in various forms, offering a versatile solution to tackle the intermittency of renewable energy sources and potentially revolutionize the entire electrical grid infrastructure. This research focusses on assessing the technical and economic feasibility of this method in six strategic coastal regions in Morocco: Laayoune, Agadir, Essaouira, Eljadida, Casablanca and Larache. Our proposed system integrates offshore wind turbines, oscillating water column wave energy converters, and PEM electrolyzers, to meet energy demands while aligning with global sustainability objectives. Significant electricity production estimates are observed across these regions, ranging from 14 MW to 20 MW. Additionally, encouraging annual estimates of hydrogen production, varying between 20 and 40 tonnes for specific locations, showcase the potential of this approach. The system's performance demonstrates promising efficiency rates, ranging from 13% to 18%, while maintaining competitive production costs. These findings underscore the ability of oceanic energy-driven green hydrogen to diversify Morocco's energy portfolio, bolster water resilience, and foster sustainable development. Ultimately, this research lays the groundwork for comprehensive energy policies and substantial infrastructure investments, positioning Morocco on a trajectory towards a decarbonized future powered by innovative and clean technologies. [ABSTRACT FROM AUTHOR]

The energy produced from renewable sources (solar, wind, hydro, geothermal, and biomass) provides direct access to clean and safe energy. Offshore wind energy, generated through wind farms, has traditionally relied on fixed structures, whereas innovative floating structures have been commercially applied since 2017. This study investigates offshore areas in Montenegro suitable for wind farm construction. Research on average annual wind speeds has successfully identified a surface area deemed suitable for constructing a wind farm in the Montenegrin part of the Adriatic Sea. Analysis of available bathymetric databases has pinpointed technical solutions for the supporting structures of wind turbines required to construct an offshore wind farm. Applying an assessment method to the defined surface of Montenegrin waters, seven blocks have been identified as suitable for wind farm construction. The research results indicate that wind farms can be built in Montenegrin waters with a technical potential corresponding to a total capacity of 2299.794 MW, which includes 2034.48 MW for floating structures, 126.759 MW for fixed structures, and 138.555 MW for jacket-fixed structures. [ABSTRACT FROM AUTHOR]

With the expansion of offshore renewable energy, countries across the world are researching the different ways to maximize the space between wind turbines by coupling multiple maritime activities within the same ocean space. This technique is referred to as co-location and can result in economic and environmental benefits. Using data from a choice experiment and random utility modeling, this research quantifies public preferences for various co-location options within the lease area of a developing wind farm off Virginia's coastline. Our estimates show that the average Virginia public household is willing-to-pay upwards of $20 per 1,000 acres for co-location activities. By comparing our results to estimated implementation and management costs of each activity, there is a strong indication that the benefits of co-location exceed the costs. The experimental design of this study can be applied to other offshore wind installments around the U.S. and abroad. [ABSTRACT FROM AUTHOR]