COASTAL BATHYMETRY FROM SATELLITE AND ITS USE ON COASTAL MODELLING

Offshore wind farms around the world are being developed with the objective of increasing the contribution of renewable energy to the global energy consumption. Bathymetric features at the wind farm sites have a strong influence on waves and currents, controlling the propagation and dissipation of flows during normal and extreme conditions. In this work we use a state-of-the-art cost-effective method for bathymetric mapping based on high resolution satellite images to characterize a coastal wind farm region and assess the added value of such data when performing wave modelling. The study area is characterized by the presence of offshore wind farms and a complex bathymetry that feature sand bars and channels. For this study, a satellite derived bathymetry (SDB) was produced using imagery from the Sentinel-2A satellite. The Sentinel-2a data allows for more detailed SDB retrieval than is available in the existing accessible bathymetric datasets. The data is then used in a spectral wave model (MIKE21SW) with different resolutions outlining the impact of large bedforms on surface waves, mainly due to wave breaking. The bathymetry data is also used in a phase-resolving model (MIKE3waveFM) where regular and irregular waves are simulated, outlining the impact of bedforms on individual wave dissipation. Discussion on the satellite derived bathymetry and wave models results are presented in this paper.

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Coastal protection of the Romanian nearshore throughout hybrid wave and offshore wind farms

E3S Web of Conferences ◽

10.1051/e3sconf/20185101004 ◽

2018 ◽

Vol 51 ◽

pp. 01004

Author(s):

Alina Raileanu ◽

Florin Onea ◽

Liliana Rusu

Keyword(s):

Wind Farm ◽

Wind Farms ◽

Wave Model ◽

Reference Points ◽

Offshore Wind ◽

Wave Transformation ◽

The Black Sea ◽

Coastal Protection ◽

Offshore Wind Farms ◽

The Impact

The objective of the present work is to estimate the influence of several hybrid wind and wave farm configurations on the wave conditions reported in the vicinity of the Saint George coastal area, in the Romanian nearshore of the Black Sea. Based on the wave data coming from a climatological database (ERA20C) and also on in situ measurements, it was possible to identify the most relevant wave patterns, which will be further considered for assessment. The numerical simulations were carried out with the SWAN (Simulating Waves Nearshore) wave model, which may provide a comprehensive picture of the wave transformation in the presence of the marine farms. Although the impact of the wind farm is not visible from the spatial maps, from the analysis of the values corresponding to the reference points, it was noticed that a maximum variation of 2% may occur for several wave parameters.

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Coastal protection of the Romanian nearshore throughout hybrid wave and offshore wind farms

E3S Web of Conferences ◽

10.1051/e3scconf/20185101004 ◽

2018 ◽

Vol 51 ◽

pp. 01004

Author(s):

Alina Raileanu ◽

Florin Onea ◽

Liliana Rusu

Keyword(s):

Wind Farm ◽

Wind Farms ◽

Wave Model ◽

Reference Points ◽

Offshore Wind ◽

Wave Transformation ◽

The Black Sea ◽

Coastal Protection ◽

Offshore Wind Farms ◽

The Impact

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An ecosystem approach for studying the impact of offshore wind farms: a French case study

ICES Journal of Marine Science ◽

10.1093/icesjms/fsy125 ◽

2018 ◽

Vol 77 (3) ◽

pp. 1238-1246 ◽

Cited By ~ 1

Author(s):

Jean-Philippe Pezy ◽

Aurore Raoux ◽

Jean-Claude Dauvin

Keyword(s):

Network Analysis ◽

Wind Farm ◽

Wind Farms ◽

Sampling Strategy ◽

Ecosystem Approach ◽

Offshore Wind ◽

Ecosystem Structure ◽

Offshore Wind Farms ◽

Ecopath Model ◽

The Impact

Abstract The French government is planning the construction of offshore wind farms (OWF) in the next decade (around 2900 MW). Following the European Environmental Impact Assessment Directive 85/337/EEC, several studies have been undertaken to identify the environmental conditions and ecosystem functioning at selected sites prior to OWF construction. However, these studies are generally focused on the conservation of some species and there is no holistic approach for analysing the effects arising from OWF construction and operation. The objective of this article is to promote a sampling strategy to collect data on the different ecosystem compartments of the future Dieppe-Le Tréport (DLT) wind farm site, adopting an ecosystem approach, which could be applied to other OWFs for the implementation of a trophic network analysis. For that purpose, an Ecopath model is used here to derive indices from Ecological Network Analysis (ENA) to investigate the ecosystem structure and functioning. The results show that the ecosystem is most likely detritus-based, associated with a biomass dominated by bivalves, which could act as a dead end for a classic trophic food web since their consumption by top predators is low in comparison to their biomass. The systemic approach developed for DLT OWF site should be applied for other French and European installations of Offshore Wind Farm.

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Coupled Dynamics Modelling of a Floating Wind Farm With Shared Mooring Lines

Volume 10: Ocean Renewable Energy ◽

10.1115/omae2018-78489 ◽

2018 ◽

Author(s):

Matthew Hall ◽

Patrick Connolly

Keyword(s):

Wind Farm ◽

Numerical Models ◽

Wind Farms ◽

Offshore Wind ◽

Irregular Waves ◽

Mooring Line ◽

Sea State ◽

Mooring Lines ◽

Offshore Wind Farms ◽

Phase Relationships

This work presents a coupling of numerical models to allow simulation of a farm of floating wind turbines in which some mooring lines are shared between platforms. This shared mooring approach has potential to reduce mooring costs for floating offshore wind farms, but introduces additional complexity in system behaviour and design considerations for which new simulation capabilities are needed. Multiple instances of the FAST floating wind turbine simulator are coupled modularly to the MoorDyn mooring system simulator to achieve a coupled simulation of a full shared-mooring floating wind farm. The model is demonstrated on a square-shaped four-turbine shared mooring farm configuration in the presence of irregular waves and turbulent winds. Results show reasonable behaviour of the platform motions, with surge displacements under wind and wave loading that reflect the complex restoring properties of the shared mooring arrangement. Varying phase relationships in the platforms’ motions arising from their spatial offsets in the sea state show that the shared mooring lines will see different excitation at either end. Fluctuations in the mooring line tensions bear out this fact, and also show the importance of line dynamics in these shared mooring arrangements. In particular, the shared mooring lines show a greater tendency for resonance due to the absence of seabed contact.

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Wind Flow Conditions in Offshore Wind Farms: Validation and Application of a CFD Wake Model

Green ◽

10.1515/green-2013-0005 ◽

2013 ◽

Vol 3 (1) ◽

Author(s):

Annette Westerhellweg ◽

Beatriz Cañadillas ◽

Friederike Kinder ◽

Thomas Neumann

Keyword(s):

Wind Farm ◽

Atmospheric Stability ◽

Wind Farms ◽

Offshore Wind ◽

Wind Flow ◽

Flow Conditions ◽

Offshore Wind Farms ◽

Speed Reduction ◽

Wake Model ◽

The Impact

AbstractSince August 2009, the first German offshore wind farm ‘alpha ventus’ is operating close to the wind measurement platform FINO1. Within the research project RAVE-OWEA the wind flow conditions in ‘alpha ventus’ were assessed in detail, simulated with a CFD wake model and compared with the measurements. Wind data measured at FINO1 have been evaluated for wind speed reduction and turbulence increase in the wake. Additionally operational data were evaluated for the farm efficiency. The atmospheric stability has been evaluated by temperature measurements of air and water and the impact of atmospheric stability on the wind conditions in the wake has been assessed. As an application of CFD models the generation of power matrices is introduced. Power matrices can be used for the continual monitoring of the single wind turbines in the wind farm. A power matrix based on CFD simulations has been created for ‘alpha ventus’ and tested against the measured data.

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Simulation Based Investigation of the Impact of Information Sharing on the Offshore Wind Farm Installation Process

Journal of Renewable Energy ◽

10.1155/2017/8301316 ◽

2017 ◽

Vol 2017 ◽

pp. 1-11 ◽

Cited By ~ 8

Author(s):

Moritz Quandt ◽

Thies Beinke ◽

Abderrahim Ait-Alla ◽

Michael Freitag

Keyword(s):

Resource Availability ◽

Information Acquisition ◽

Wind Farm ◽

Wind Farms ◽

Limited Resource ◽

Energy Generation ◽

Green Energy ◽

Offshore Wind ◽

Offshore Wind Farms ◽

The Impact

In the recent decades, the introduction of a sustainable and green energy infrastructure, and, by this, the reduction of emissions caused by fossil energy generation, has been focused on by industry-oriented nations worldwide. Among the technologies of renewable energy generation, wind energy has the highest deployment rate, due to the high wind resource availability and the high technology maturity reached mainly by the onshore installation of wind turbines. However, the planning and the installation of offshore wind farms are a challenging task, because of harsh weather conditions and limited resource availability. Due to the current practice of decentralised information acquisition by the supply chain partners, we investigate the impact of sharing information on the installation process of offshore wind farms by means of a simulation model. Therefore, relevant information items will be identified in order to improve the installation process.

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

Energies ◽

10.3390/en14206559 ◽

2021 ◽

Vol 14 (20) ◽

pp. 6559

Author(s):

Krzysztof Naus ◽

Katarzyna Banaszak ◽

Piotr Szymak

Keyword(s):

Wind Farm ◽

Wind Farms ◽

Offshore Wind ◽

Automatic Identification ◽

Identification System ◽

Large Set ◽

Data Set ◽

Offshore Wind Farms ◽

Automatic Identification System ◽

The Impact

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.

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Assessment of Condition Monitoring Techniques for Offshore Wind Farms

Journal of Solar Energy Engineering ◽

10.1115/1.2931512 ◽

2008 ◽

Vol 130 (3) ◽

Cited By ~ 56

Author(s):

Edwin Wiggelinkhuizen ◽

Theo Verbruggen ◽

Henk Braam ◽

Luc Rademakers ◽

Jianping Xiang ◽

...

Keyword(s):

Condition Monitoring ◽

Wind Farm ◽

Early Stage ◽

Wind Farms ◽

Added Value ◽

Offshore Wind ◽

Monitoring Systems ◽

Power Performance ◽

Offshore Wind Farms ◽

Condition Monitoring Systems

This paper discusses the results of an extensive investigation to assess the added value of various techniques of health monitoring to optimize the maintenance procedures of offshore wind farms. This investigation was done within the framework of the EU funded Condition Monitoring for Offshore Wind Farms (CONMOW) project, which was carried out from 2002 to 2007. A small wind farm of five turbines has been instrumented with several condition monitoring systems and also with the “traditional” measurement systems for measuring mechanical loads and power performance. Data from vibration and traditional measurements, together with data collected by the turbine’s system control and data acquisition (SCADA) systems, have been analyzed to assess (1) if failures can be determined from the different data sets; (2) if so, if they can be detected at an early stage and if their progress over time can be monitored; and (3) if criteria are available to assess the component’s health. Several data analysis methods and measurement configurations have been developed, applied, and tested. This paper first describes the use of condition monitoring if condition based maintenance is going to be applied instead of only scheduled and corrective maintenance. Second, the paper describes the CONMOW project and its major results, viz., the assessment of the usefulness and capabilities of condition monitoring systems, including algorithms for identifying early failures. Finally, the economic consequences of applying condition monitoring systems have been quantified and assessed.

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Observed and simulated turbulent kinetic energy (WRF 3.8.1) overlarge offshore wind farms

10.5194/gmd-2019-100 ◽

2019 ◽

Cited By ~ 1

Author(s):

Simon K. Siedersleben ◽

Andreas Platis ◽

Julie K. Lundquist ◽

Bughsin Djath ◽

Astrid Lampert ◽

...

Keyword(s):

Boundary Layer ◽

Wind Speed ◽

Wind Farm ◽

Wind Farms ◽

Horizontal Resolution ◽

Offshore Wind ◽

Vertical Resolution ◽

Offshore Wind Farms ◽

The Impact ◽

Simulated Wind

Abstract. Because wind farms affect local weather and microclimates, parameterizations of their effects have been developed for numerical weather prediction models. While most wind farm parameterizations (WFP) 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 allowing 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 in 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 above the wind farm. Furthermore, using fine vertical resolution increases the agreement of the simulated wind speed with satellite observations of surface wind speed.

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

Geoscientific Model Development ◽

10.5194/gmd-13-249-2020 ◽

2020 ◽

Vol 13 (1) ◽

pp. 249-268 ◽

Cited By ~ 6

Author(s):

Simon K. Siedersleben ◽

Andreas Platis ◽

Julie K. Lundquist ◽

Bughsin Djath ◽

Astrid Lampert ◽

...

Keyword(s):

Boundary Layer ◽

Wind Speed ◽

Wind Farm ◽

Wind Farms ◽

Horizontal Resolution ◽

Offshore Wind ◽

Vertical Resolution ◽

Offshore Wind Farms ◽

The Impact ◽

Simulated Wind

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.

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