Impact Of Offshore Wind Farms Research Articles

Strong site fidelity, residency and local behaviour of Atlantic cod ( Gadus morhua ) at two types of artificial reefs in an offshore wind farm

Globally, biogenic temperate reefs are among the most threatened habitats. In the North Sea in particular, large shellfish reefs were lost owing to fishing activities in the 1900s. The impact of offshore wind farms (OWFs) on marine wildlife is extensive, and it offers the possibility to reintroduce new hard substrate habitats that are protected from fisheries at a large scale. In addition to the submerged structures of OWFs, marine hard substrate habitat can be further enhanced by providing extra artificial reefs. In an operational OWF along the Dutch coast, four artificial reefs (two with a scour bed and two without) were deployed in the vicinity of a wind turbine. Acoustic telemetry was used to monitor the fine-scale movement of 64 Atlantic cod ( Gadus morhua ). The monitoring ran from July 2021 to January 2023. Detailed information on behaviour, area utilization and attraction to the structures was determined. Results showed strong attraction (high site fidelity and residency) to the artificial reef, with no significant difference between the two tested types of reefs, and only a few individuals staying over winter. Cod spent a large proportion of their time hiding in the artificial reefs, suggesting that adding pipes for shelter has a beneficiary effect.

Answering the key stakeholder questions about the impact of offshore wind farms on marine life using hypothesis testing to inform targeted monitoring

Abstract Stakeholders need scientific advice on the environmental impacts of offshore wind (OW) before the facilities are installed. The utility of conventional environmental monitoring methods as a basis for forecasting OW impacts is limited because they do not explain the causes of the observed effects. We propose a multistep approach, based on process-oriented hypothesis testing, targeted monitoring and numerical modeling, to answer key stakeholder questions about planning an OW facility: Q1—Where do we place future OW farms so that impacts on the ecosystem are minimized? Q2—Which species and ecosystem processes will be impacted and to what degree? Q3—Can we mitigate impacts and, if so, how? and Q4—What are the risks of placing an OW facility in one location vs. another? Hypothesis testing can be used to assess impacts of OW facilities on target species-ecological process. This knowledge is transferable and is broadly applicable, a priori, to assess suitable locations for OW (Q1). Hypothesis testing can be combined with monitoring methods to guide targeted monitoring. The knowledge generated can identify the species/habitats at risk (Q2), help selecting/developing mitigation measures (Q3), and be used as input parameters for models to forecast OW impacts at a large spatial scale (Q1; Q4).

A new method for quantifying redistribution of seabirds within operational offshore wind farms finds no evidence of within-wind farm displacement

The climate crisis is driving a rapid increase in size and number of offshore wind farms to reduce carbon emissions from electricity generation. However, there are concerns about the potential impact of offshore wind farms on the marine environment. Seabirds are considered to be at risk of being displaced from preferred foraging habitat, by construction and operation of offshore wind farms, resulting in reduced energy intake or elevated energetic costs and consequent decreases in survival and/or productivity. Typically, displacement or avoidance behaviour is assessed by comparing abundance and spatial distributions of seabirds before and after an offshore wind farm is constructed. However, seabird distributions are highly variable through time and space and so discerning a change in distribution caused by an offshore wind farm from other environmental variables can be challenging. We present a new method that controls for temporal variation by examining the location of individual seabirds relative to turbines. Mean seabird density at different distances from individual turbines (0-400m) was calculated from data collected on a total of 12 digital aerial surveys of the Beatrice Offshore Wind Farm (UK), in May-August in 2019 and 2021. Mean densities of common guillemot (Uria aalge), razorbill (Alca torda), Atlantic puffin (Fratercula arctica) and black-legged kittiwake (Rissa tridactyla), both flying and sat on the water, were calculated. If the presence of turbines had no effect on seabird distribution, there should be no relationship between distance from turbine and seabird density. This was tested by simulating a relocation of turbines, relative to seabird distribution, and recalculating seabird density over 0-400m from simulated turbine locations. This was repeated to generate a bootstrapped distribution of expected densities against which observed density was compared. If displacement was occurring, mean observed density close to turbines would be significantly lower than expected density, derived from the bootstrap distribution. Overall, observed mean density did not differ significantly from expected density, i.e. no displacement effect was detected. There was a slight tendency for guillemot and razorbill, when sat on the water, to be at higher densities than expected, near turbines, suggestive of possible attraction to turbines, and for flying birds to be at lower densities than expected, near turbines, suggestive of possible avoidance. No flying razorbills were recorded within 100m of turbines but sample sizes were small. Kittiwake tended to show no avoidance or attraction behaviour, although flying kittiwake density was slightly lower than expected at 200m from turbines. Puffins sat on the water were recorded in densities similar to the expected density. Overall, no effect of turbine rotor speed was found, i.e. birds were not more likely to be displaced/avoid turbines at higher or lower rotor speeds. The results of the turbine relocation analysis gave a more consistent and more easily interpreted assessment of displacement/avoidance behaviour than the typical approaches of comparing abundance and seabird distribution through time. We strongly encourage application of this new approach to post-construction spatial distribution data from other offshore wind farms, to build the evidence base on the effects of offshore wind farms on seabirds.

Modeling Wind Turbines to Assess Impact of Offshore Wind Farms on Maritime X- and S-band Radars

This article discusses several aspects related to modeling the impact of offshore wind farms on maritime radar systems operating in the X and S bands. The first part of the paper focuses on theoretical models and analyses, taking into account radio shadowing and false radar echoes. Additionally, the issue of spatial modeling of wind turbines, with diffraction phenomena considered, is reviewed with the help of suitable propagation models. By relaying on a software-based implementation of the proposed model, the authors carried out a detailed simulation of the impact of wind turbines on radar systems operating in the X and S bands. The results of these simulations are presented and discussed in the second part of the article.

Study on the Impact of Offshore Wind Farms on Surrounding Water Environment in the Yangtze Estuary Based on Remote Sensing

Offshore wind farms (OWFs), built extensively in recent years, induce changes in the surrounding water environment. The changes in the suspended sediment concentration (SSC) and chlorophyll-a concentration (Chl-aC) induced by an OWF in the Yangtze River Estuary were analyzed based on Chinese Gaofen (GF) satellite data. The results show the following: (1) The flow near the wind turbines makes the bottom water surge, driving the sediment to “re-suspend” and be lost, deepening the scour pit around the bottom of the wind turbines, which is known as “self-digging”. The interaction between the pillar of a wind turbine and tidal currents makes hydrodynamic factors more complicated. Blocking by wind turbines promoting the scour of the bottom seabed of the OWF results in speeding up the circulation rate of sediment loss and “re-suspension”, which contributes to the change in the SSC and Chl-aC. This kind of change in sediment transport in estuarine areas due to human construction affects the balance of the ecological environment. Long-term sediment loss around wind turbines also influences the safety of wind turbines. (2) The SSC and Chl-aC are mainly in the range of 200–600 mg/L and 3–7 μg/L, respectively, in the OWF area, higher than the values obtained in surrounding waters. The SSC and Chl-aC downstream of the OWF are higher than those upstream, with differences of 100–300 mg/L and 0.5–2 μg/L. High SSC and Chl-aC “tails” appear downstream of wind turbines, consistent with the direction of local tidal currents, with lengths in the range of 2–4 km. In addition, the water environment in the vicinity of a wind turbine array, with a roughly 2–5 km scope (within 4 km during flooding and around 2.5 km during ebbing approximately) downstream of the wind turbine array, is impacted by the OWF. (3) In order to solve the problem of “self-digging” induced by OWFs, it is suggested that the distance between two wind turbines should be controlled within 2–3.5 km in the main flow direction, promising that the second row of wind turbines will be placed on the suspended sediment deposition belt induced by the first row. In this way, the problems of ecosystem imbalance and tidal current structure change caused by sediment loss because of local scouring can be reduced. Furthermore, mutual compensation between wind turbines can solve the “self-digging” problem to a certain extent and ensure the safety of OWFs.

Extended reality-based choice experiment to assess the impact of offshore wind turbines in historic center: The case of Manfredonia

This paper proposes a novel four-step methodology to achieve an extended-reality-based choice experiment in historic and touristic centers. The study exploits the case of Manfredonia (a seaside town in southern Italy) to apply the new approach and investigates public attitudes and preferences towards the installation of offshore wind turbines in the area. The novelty of the proposed work is twofold: i) for the first time, a structured methodological approach is defined for the development of a hybrid extended-reality-based choice experiment; ii) the perception of the visual impact of offshore wind turbines is assessed in a touristic and historic city in southern Italy exploiting the proposed approach. Our findings underscore the importance of continuously monitoring public perceptions to maintain and promote support for sustainable energy solutions, particularly in relation to the perception of wind energy's visual impact. In particular, 65% of respondents express their worries about wind power plants impact on the landscape. Moreover, the positive coefficient of the visual impact (0.011) suggests a positive utility of respondents from a higher off-shore turbines' density and a marginal willingness to accept a compensation of about 13€ for the visual impact and of about 33€ for the distance from the shore. In this context the use of extended reality technology in choice experiment scenarios significantly improves the results and enhances the understanding of the landscape impact of offshore wind farms.

Avoidance of offshore wind farms by Sandwich Terns increases with turbine density

Abstract The expanding use of wind farms as a source of renewable energy can impact bird populations due to collisions and other factors. Globally, seabirds are one of the avian taxonomic groups most threatened by anthropogenic disturbance; adequately assessing the potential impact of offshore wind farms (OWFs) is important for developing strategies to avoid or minimize harm to their populations. We estimated avoidance rates of OWFs—the degree to which birds show reduced utilization of OWF areas—by Sandwich Terns (Thalasseus sandvicensis) at 2 breeding colonies in western Europe: Scolt Head (United Kingdom) and De Putten (the Netherlands). The foraging ranges of birds from each colony overlapped with multiple OWFs. We modeled GPS tracking data using integrated step selection functions (iSSFs) to estimate the relative selection of habitats at the scale of time between successive GPS relocations—in our case, 10 min, in which Sandwich Terns traveled ~2 km on average. Besides the effects of OWFs and the direct surroundings of OWFs, iSSFs considered distance from the colony and habitat characteristics (water depth and sediment grain size) as well as movement characteristics. Macro-avoidance rates, where 1 means complete avoidance, were estimated at 0.54 (95% CI: 0.35, 0.7) for birds originating from Scolt Head and 0.41 (95% CI: 0.21, 0.56) for those from De Putten. Estimates for individual OWFs also indicated avoidance but were associated with considerable uncertainty. Our results were inconclusive with regard to the behavioral response to the areas directly surrounding OWFs (within 1.5 km); estimates suggested indifference and avoidance, and were associated with large uncertainty. Avoidance rate of OWFs significantly increased with turbine density, suggesting that OWF design may help to reduce the impact of OWFs on Sandwich Terns. The partial avoidance of OWFs by Sandwich Terns implies that the species will experience risks of collision and habitat loss due to OWFs constructed within their foraging ranges.

Impact of offshore wind farms on a tropical depression through the amplification effect by the downstream mountainous terrain

The influence of offshore wind farms in the northern South China Sea on a tropical depression far away (over the Beibu Gulf) is investigated through a fully coupled atmosphere-ocean model. Results show that in the experimental run with the offshore wind farms, the tropical depression located downstream of the wind farm are maintained for longer periods of time. This is mainly due to the stronger convection on the western side of the tropical depression. The stronger convergence in the lower level and divergence in the upper level caused by low-level gravity waves become the key dynamic condition. The primary factor influencing such gravity waves is the rapid decrease of the low-level vertical wind shear. The diagnostic analysis shows that wind-farm wakes affect the local low-level vertical velocity through the downstream mountainous terrain, which makes the vertical momentum term as the main contributing term affecting the variation of the horizontal momentum and subsequently the low-level vertical wind shear. This amplified impact of wind farms through the mountainous terrain may also occur in other regions.

The impact of offshore wind farms on the latent heat flux

The impact of offshore wind farms on the latent heat flux

Integration criteria of offshore wind farms in the landscape: Viewpoints of local inhabitants

The offshore wind energy sector will flourish in the next few decades to meet global climate change commitments and energy demand. All EU Member States are required to develop marine spatial planning in order to facilitate the transition to a green economy. Even though these proposed offshore wind farms are essential for the energy transition, the visual impact of their implementation could serve as an obstacle to their deployment.A methodological framework is proposed to assess the visual impact of offshore wind farms. The current paper quantifies their visual impact, compares the results with nearby citizens' opinions, and proposes a realistic approach. Personal interviews took place in August to meet as many people as possible since these villages are primarily touristic.In both examined scenarios, according to the results of the methodology (Greek legislation) the first limitation is met, so there is no or minimal visual impact. Furthermore, the respondents replied that they would not experience any optical disturbance from an offshore wind farm in their region. Additionally, according to the respondents, 64% are positive or very positive about renewable energy exploitation, and only 11% are against it regardless of their age.

The large-scale impact of anthropogenic mixing by offshore wind turbine foundations in the shallow North Sea

Structure drag from offshore wind turbines and its physical impacts on the marine environment of the German Bight are investigated in this study. The flow past vertical cylinders, such as wind turbine foundations, and associated turbulent mixing has long been studied, but questions remain about anticipated regional implications of offshore wind infrastructure on physical and biogeochemical conditions. Here, we present two existing modeling approaches for simulating wind turbine foundation effects in regional ocean models and discuss the problematic use of very high resolution in hydrostatic modeling. By implementing a low-resolution structure drag parameterization in an unstructured-grid model, we demonstrate the impacts of monopile drag on hydrodynamic conditions, validated against recent in-situ measurements. Although the anthropogenic mixing is confined at wind farm sites, our simulations show that structure-induced mixing affects much larger, regional scales. The additional turbulence production emerges as the driving mechanism behind the monopile impacts, leading to changes in both the current velocities and stratification, with magnitudes of about 10%, similar in magnitude to regional annual and interannual variabilities. This study provides new insights into the hydrodynamic impact of offshore wind farms at their current development levels and emphasizes the need for further research in view of potential restructuring of the future coastal environment.

Assessment of the visual impact of offshore wind farms

The decarbonization of energy power generation is the main ambition globally. In this new era, the development of offshore wind farms (OWFs) will play a vital role. So, the social acceptability of the deployment of offshore wind farms has to be investigated in detail.The principal goal of this study is to test existing tools for the assessment of the visual impact due to an OWF. Improvements were also suggested, when it was found that the factors did not correspond to reality.The adopted methodology compared the results from the original Spanish method, Spanish method II, Greek legislation, local people surveys, and innovative combinations of scenarios to minimize the visual impact. The software tools AutoCAD, ArcGIS, and Google Earth were also employed.The study area is Kissamos, Western Crete. The results showed that the original Spanish method had a deviation of 88.0% from the public opinion and, hence, the method requires improvements according to today's data. On the contrary, one of the new suggested scenarios was verified to be more concise and accurate, reaching a deviation of 19.7%.

A bibliometric review on the implications of renewable offshore marine energy development on marine species

The growing global demand for sustainable and environmentally friendly energy has stimulated the rapid adoption of renewable offshore energy. However, infrastructure needed for green energy production ironically impacts upon marine species and biodiversity. Consequently, this positional review paper seeks to comprehensively synthesise the prevailing body of knowledge on the impact of offshore energy development on a broad range of marine species. An interpretivist philosophical stance and inductive reasoning was adopted using scientometric analysis to conduct a rich synthesis of extant literature. From an operational perspective, the Scopus database was utilised to search for key terms on the phenomena under investigation and using the VoS Viewer software for the identification of trends using scientometric maps. The analysis reveals that research in this area of science has increased significantly over the last decade but private sector involvement is conspicuous by its absence. Primary concerns among the research community include the impact of energy development on the abundance of species, pollution and biodiversity behaviour and migration. At present, researchers have extensively focused on the impact of offshore wind farms on fish and marine mammals. However, the literature reveals no significant long-term impact upon energy development on most marine species albeit, short-term interference has raised concerns (from sound, disruption of navigation and foraging patterns, and damage of habitat). To minimise short term disruption, researchers have recommended the use of acoustic deterrence during construction, enforcement of protected areas and continued research.

The Methodology for Assessing the Impact of Offshore Wind Farms on Navigation, Based on the Automatic Identification System Historical Data

Mounting offshore renewable energy installations often involves extra risk regarding the safety of navigation, especially for areas with high traffic intensity. The decision-makers planning such projects need to anticipate and plan appropriate solutions in order to manage navigation risks. This process is referred to as “environmental impact assessment”. In what way can these threats be reduced using the available Automatic Identification System (AIS) tool? This paper presents a study of the concept for the methodology of an a posteriori vessel traffic description in the form of quantitative and qualitative characteristics created based on a large set of historical AIS data (big data). The research was oriented primarily towards the practical application and verification of the methodology used when assessing the impact of the planned Offshore Wind Farm (OWF) Baltic II on the safety of ships in Polish Marine Areas, and on the effectiveness of navigation, taking into account the existing shipping routes and customary and traffic separation systems. The research results (e.g., a significant distance of the Baltic II from the nearest customary shipping route equal to 3 Nm, a small number of vessels in its area in 2017 amounting to only 930) obtained on the basis of the annual AIS data set allowed for an unambiguous and reliable assessment of the impact of OWFs on shipping, thus confirming the suitability of the methodology for MREI spatial planning.

The Impact of Offshore Wind Farms on Sea State Demonstrated by Airborne LiDAR Measurements

The increasing number of wind farms installed in the North Sea has an impact on the downstream wind speed. This has been hypothesized as well for sea state properties. Wave effects can be expected in particular in fetch-limited conditions with offshore wind directions. With systematic flights deploying an airborne laser scanner, these impacts are shown directly for the first time. The flights were conducted perpendicular to the main wind direction upstream and downstream of the cluster of the offshore wind parks Amrumbank West, Nordsee Ost, and Meerwind Süd/Ost. The flight legs covered the area potentially influenced by the wind parks and the undisturbed area next to the wind parks. The analysis of the spectral energy distribution shows a re-distribution of the wave energy in the downstream area with enhanced energy at smaller wavelengths. The effect is still clearly visible at a distance of 55 km. As the sea surface constitutes the link between the atmosphere and the ocean, it is very likely that wind parks modify the properties of the water column as well.

Offshore Wind Farm Footprint on Organic and Mineral Particle Flux to the Bottom

Offshore wind farms (OWFs) are an important source of renewable energy accounting for 2.3% of the European Union's electricity demand. Yet their impact on the environment needs to be assessed. Here, we couple a hydrodynamic (including tides and waves) and sediment transport model with a description of the organic carbon and mineral particle dynamics in the water column and sediments. The model is applied to the Belgian Coastal Zone (BCZ) where OWFs currently occupy 7% of its surface area which is estimated to double in the next 5 years. The impact of OWFs on the environment is represented through the filtration of the water column and fecal pellets production by the blue mussel, the dominant fouling organism. Our model simulations show that the impact of biodeposition on the mud particle sedimentation and on sediment composition is small compared to the fluxes associated with tidal deposition and resuspension and the lateral inputs. In contrast, the total organic carbon (TOC) flux to the sediment is significantly altered inside the OWF perimeters and TOC deposition is increased up to 50% in an area 5 km around the monopiles. Further away, the TOC flux to the bottom decreases with a notable effect up to 30 km away. The major changes are found along the direction of the main residual current and tidal ellipse's major axis. In addition, sub-mesoscale gyres act as retention areas with increased carbon deposition. A future OWF in the BCZ will be located close to gravel beds in a Natura 2000 area, considered as vulnerable habitats and biodiversity hotspots. The different scenarios for this OWF, varying in turbine number and positioning, are compared in terms of impact on the carbon and mineral particle deposition flux in the BCZ and, particularly, to these gravel beds. The scenarios show that the number of turbines has only a slight impact on the TOC deposition flux, unlike their positioning that significantly alters the TOC flux to the gravel beds. The TOC deposition flux exceeds 50%, when the turbines are placed next to the gravel beds; while a limited increase is simulated, when the turbines are located the farthest possible from them.

The Potential Impact of Offshore Wind Farms on Fishes and Invertebrates

The Potential Impact of Offshore Wind Farms on Fishes and Invertebrates

Impact of Offshore Wind Farms on Marine Ecosystems, Pelagic Species and Fishing

Negro, V.; Del Campo, J.M.; Luengo Frades, J.; Martin Anton, M.; Esteban, M.D.; Lopez – Gutierrez, J.S., and Soukissian, T., In: Malvarez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 118–122. Coconut Creek (Florida), ISSN 0749-0208.The evolution of the clean energies is one of the targets of the Sustainable Development Goals (SDG) of the United Nations (UN 2015 – 2030). However, the increase in the number of marine wind farms (gravity based structures < 10%; piles < 82% and jackets, tripod, tripile and floating installations 7%) with a progressive growth in depth, distance from shore, power and diameter, requires a deep reflection. The marine growth in piles and GBS structures would be studied if it is beneficial for marine ecosystems and fish species, displacement and colonization of new ones. After the installation, new substrates became colonised by a wide variety of benthic organisms. The objective of this research manuscript is to pose this challenge and the analysis in countries like Spain and the Mediterranean Countries where tourism is one of the main sources weath and the environment and landscape are essential in the preservation of the territory and the harmony with nature.

Turbulent kinetic energy over large offshore wind farms observed and simulated by the mesoscale model WRF (3.8.1)

Abstract. Wind farms affect local weather and microclimates; hence, parameterizations of their effects have been developed for numerical weather prediction models. While most wind farm parameterizations (WFPs) include drag effects of wind farms, models differ on whether or not an additional turbulent kinetic energy (TKE) source should be included in these parameterizations to simulate the impact of wind farms on the boundary layer. Therefore, we use aircraft measurements above large offshore wind farms in stable conditions to evaluate WFP choices. Of the three case studies we examine, we find the simulated ambient background flow to agree with observations of temperature stratification and winds. This agreement allows us to explore the sensitivity of simulated wind farm effects with respect to modeling choices such as whether or not to include a TKE source, horizontal resolution, vertical resolution and advection of TKE. For a stably stratified marine atmospheric boundary layer (MABL), a TKE source and a horizontal resolution on the order of 5 km or finer are necessary to represent the impact of offshore wind farms on the MABL. Additionally, TKE advection results in excessively reduced TKE over the wind farms, which in turn causes an underestimation of the wind speed deficit above the wind farm. Furthermore, using fine vertical resolution increases the agreement of the simulated wind speed with satellite observations of surface wind speed.

Effects of established offshore wind farms on energy flow of coastal ecosystems: A case study of the Rudong offshore wind farms in China

To assess the impact of offshore wind farms (OWFs) on the structure and energy flow of coastal ecosystems, Ecopath models of the Jiangsu coastal ecosystem (JCE) based on biological field data collected before and after the establishment of the Rudong OWFs in 2007 and 2015, respectively, were constructed and compared. The results indicated that after OWF construction, detritus, phytoplankton, zooplankton, anchovies, and some benthic fish were positively impacted. The increased primary production and detritus resulted in the increased food supply for zooplankton, which made it possible for planktivorous species (particularly anchovies) to be fed. Consequently, the biomass and production of some benthic fish increased, which indicates a potential reef effect. Other groups with decreased biomasses and productions may have been negatively impacted by the OWFs. Herbivory flows dominated the pre- and post-construction JCE despite their low transfer efficiencies; however, the proportion of detritivory flow increased after OWF construction, and this was especially prominent at high trophic levels. The post-construction JCE was immature with lower system connectivity, trophic flow utilisation, and transfer efficiency. However, the ecosystem tended to develop towards higher maturity with higher energy throughput, ecosystem activity, and recycling capability.