Modelling the impact of offshore wind farms on safety radars onboard Oil and Gas platforms

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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Seismic Design for Offshore Wind Farms – Lessons Learnt From the ACE Joint Industry Project

10.1115/omae2021-63327 ◽

2021 ◽

Author(s):

Marcus Klose ◽

Junkan Wang ◽

Albert Ku

Keyword(s):

Seismic Design ◽

Wind Turbines ◽

Wind Farms ◽

The United States ◽

Offshore Wind ◽

Seismic Load ◽

Support Structures ◽

Offshore Wind Farms ◽

Asian Pacific Region ◽

The Impact

Abstract In the past, most of the offshore wind farms have been installed in European countries. In contrast to offshore wind projects in European waters, it became clear that the impact from earthquakes is expected to be one of the major design drivers for the wind turbines and their support structures in other areas of the world. This topic is of high importance in offshore markets in the Asian Pacific region like China, Taiwan, Japan, Korea as well as parts of the United States. So far, seismic design for wind turbines is not described in large details in existing wind energy standards while local as well as international offshore oil & gas standards do not consider the specifics of modern wind turbines. In 2019, DNV GL started a Joint Industry Project (JIP) called “ACE -Alleviating Cyclone and Earthquake challenges for wind farms”. Based on the project results, a Recommended Practice (RP) for seismic design of wind turbines and their support structures will be developed. It will supplement existing standards like DNVGL-ST-0126, DNVGL-ST-0437 and the IEC 61400 series. This paper addresses the area of seismic load calculation and the details of combining earthquake impact with other environmental loads. Different options of analysis, particularly time-domain simulations with integrated models or submodelling techniques using superelements will be presented. Seismic ground motions using a uniform profile or depth-varying input profile are discussed. Finally, the seismic load design return period is addressed.

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Impact of Primary Frequency Control of Offshore HVDC Grids on Interarea Modes of Power Systems

Energies ◽

10.3390/en12203879 ◽

2019 ◽

Vol 12 (20) ◽

pp. 3879 ◽

Cited By ~ 2

Author(s):

Ali Bidadfar ◽

Oscar Saborío-Romano ◽

Vladislav Akhmatov ◽

Nicolaos A. Cutululis ◽

Poul E. Sørensen

Keyword(s):

Power Systems ◽

Frequency Control ◽

Wind Farms ◽

Offshore Wind ◽

Offshore Wind Farms ◽

Dc Voltage ◽

Simultaneous Use ◽

Primary Frequency ◽

Primary Frequency Control ◽

The Impact

Offshore high-voltage DC (HVDC) grids are developing as a technically reliable and economical solution to transfer more offshore wind power to onshore power systems. It is also foreseen that the offshore HVDC grids pave the way for offshore wind participation in power systems’ balancing process through frequency support. The primary frequency control mechanism in an HVDC grid can be either centralized using communication links between HVDC terminals or decentralized by the simultaneous use of DC voltage and frequency droop controls. This paper investigates the impact of both types of primary frequency control of offshore HVDC grids on onshore power system dynamics. Parametric presentation of power systems’ electro-mechanical dynamics and HVDC controls is developed to analytically prove that the primary frequency control can improve the damping of interarea modes of onshore power systems. The key findings of the paper include showing that the simultaneous use of frequency and DC voltage droop controls on onshore converters results in an autonomous share of damping torque between onshore power systems even without any participation of offshore wind farms in the frequency control. It is also found that the resulting damping from the frequency control of offshore HVDC is not always reliable as it can be nullified by the power limits of HVDC converters or wind farms. Therefore, using power oscillation damping control in parallel with frequency control is suggested. The analytical findings are verified by simulations on a three-terminal offshore HVDC grid.

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The Experiences From the First Rounds of Offshore Wind Farm Installation in the German EEZ (Both Baltic and North Sea) and Lessons Learnt to Achieve Serial Production Status: A Consultant’s Perspective

Volume 9B: Ocean Renewable Energy ◽

10.1115/omae2014-24682 ◽

2014 ◽

Author(s):

Ekkehard Stade

Keyword(s):

Wind Farm ◽

Oil And Gas ◽

Wind Farms ◽

Oil And Gas Industry ◽

Offshore Wind ◽

Offshore Wind Farm ◽

Gas Industry ◽

Offshore Wind Farms ◽

Near Misses ◽

Construction Operation

Offshore wind farms present a lesser safety risk to operators and contractors than traditional oil and gas installations. In the post Macondo world this does not come as a surprise since the risks involved in construction, operation and maintenance of an offshore wind farm are by far lower. Even with higher probability of incidents and near misses (due to serial construction) the severity/ impact of those is considerably lower. On the other hand projects are complex, profit margins are what they are called: marginal. Hence there is no room for errors, perhaps in form of delays. If, for example, the installation completion of the turbines and the inner array cabling/ export cables are not perfectly in tune, the little commercial success that can be achieved is rapidly diminishing by costly compensation activities. The paper will try to present solutions to the most pressing challenges and elaborate on the effect those would have had, had they been implemented at the beginning of the projects. How can a sustainable new industry evolve by learning from established industries? Presently, there is a view that offshore wind is a short-lived business. Particularly representatives of the oil and gas industry raise such concern. Apart from the obvious bias of those voices, this controversy is also caused by the fact that offshore wind seems to have a tendency to try and re-invent the wheel rather than using established procedures. Even with a relatively stable commitment to the offshore wind development regardless of the respective government focus within European coastal states the industry suffers from financing issues, subsidies, over-regulation due to lack of expertise within authorities and other challenges. The avoidance of those is key to a successful development for this industry in other areas of the planet. In conjunction with a stable commitment this is essential in order to attract the long lead-time projects and to establish the complex supply chains to achieve above goals. The paper will look at the short but intensive history of the industry and establish mitigation to some of the involved risks of offshore wind farm EPCI.

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The ecology of infrastructure decommissioning in the North Sea: what we need to know and how to achieve it

ICES Journal of Marine Science ◽

10.1093/icesjms/fsz143 ◽

2019 ◽

Vol 77 (3) ◽

pp. 1109-1126 ◽

Cited By ~ 7

Author(s):

A M Fowler ◽

A -M Jørgensen ◽

J W P Coolen ◽

D O B Jones ◽

J C Svendsen ◽

...

Keyword(s):

North Sea ◽

Oil And Gas ◽

Wind Farms ◽

Complete Removal ◽

Offshore Wind ◽

Knowledge Gaps ◽

Joint Research ◽

Offshore Wind Farms ◽

The North ◽

The North Sea

AbstractAs decommissioning of oil and gas (O&G) installations intensifies in the North Sea, and worldwide, debate rages regarding the fate of these novel habitats and their associated biota—a debate that has important implications for future decommissioning of offshore wind farms (OWFs). Calls to relax complete removal requirements in some circumstances and allow part of an O&G installation to be left in the marine environment are increasing. Yet knowledge regarding the biological communities that develop on these structures and their ecological role in the North Sea is currently insufficient to inform such decommissioning decisions. To focus debate regarding decommissioning policy and guide ecological research, we review environmental policy objectives in the region, summarize existing knowledge regarding ecological aspects of decommissioning for both O&G and OWF installations, and identify approaches to address knowledge gaps through science–industry collaboration. We find that in some cases complete removal will conflict with other policies regarding protection and restoration of reefs, as well as the conservation of species within the region. Key ecological considerations that are rarely considered during decommissioning decisions are: (i) provision of reef habitat, (ii) productivity of offshore ecosystems, (iii) enhancement of biodiversity, (iv) protection of the seabed from trawling, and (v) enhancement of connectivity. Knowledge gaps within these areas will best be addressed using industry infrastructure and vessels for scientific investigations, re-analysis of historical data held by industry, scientific training of industry personnel, joint research funding opportunities, and trial decommissioning projects.

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Multi-Purpose Offshore-Platforms: Past, Present and Future Research and Developments

Volume 9: Offshore Geotechnics; Torgeir Moan Honoring Symposium ◽

10.1115/omae2017-62691 ◽

2017 ◽

Cited By ~ 1

Author(s):

Bernt J. Leira

Keyword(s):

Wind Farms ◽

Offshore Wind ◽

Future Research ◽

Offshore Platforms ◽

Offshore Wind Farms ◽

Ocean Renewable Energy ◽

Transport Maritime ◽

Optimal Coupling ◽

Environmental Feasibility ◽

The Impact

Energy, fisheries and transport infrastructures are increasingly being established offshore. Facilities such as offshore wind farms may occupy large areas and compete with other users of the maritime space. Accordingly, offshore platforms that can combine many functions within the same infrastructure could offer significant benefits. This applies to economy, optimization of spatial planning and minimization of the impact on the environment. In the present paper, some proposed innovative designs for multi-use offshore platforms are described. The technical, economical and environmental feasibility of designing, installing, operating, servicing and maintaining such platforms are discussed. The relevant platforms under consideration are targeted towards ocean renewable energy (in particular offshore wind), aquaculture and related transport maritime services. Innovative designs for multi-use offshore platforms that intend to allow optimal coupling of the various activities and services are highlighted. Issues such as safe and efficient installation, operation, maintenance and monitoring are also briefly discussed in the 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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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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COASTAL BATHYMETRY FROM SATELLITE AND ITS USE ON COASTAL MODELLING

Coastal Engineering Proceedings ◽

10.9753/icce.v36.papers.98 ◽

2018 ◽

pp. 98

Author(s):

Rodolfo BolaÃ±os ◽

Lars Boye Hansen ◽

Mikkel Lydholm Rasmussen ◽

Maziar Golestani ◽

Jesper Sandvig Mariegaard ◽

...

Keyword(s):

Wind Farm ◽

Wind Farms ◽

Wave Model ◽

Added Value ◽

Offshore Wind ◽

Irregular Waves ◽

Offshore Wind Farms ◽

High Resolution Satellite Images ◽

Sentinel 2A ◽

The Impact

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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