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

2017 ◽  
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.

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

2018 ◽  
Vol 77 (3) ◽  
pp. 1238-1246 ◽  
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.

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

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.

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

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3879 ◽  
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.

scholarly journals High Voltage DC Transmission Systems for Offshore Wind Farms with Different Topologies

2019 ◽  
Vol 8 (11) ◽  
pp. 2354-2363
Keyword(s):  
High Voltage ◽  
Large Scale ◽  
Wind Farms ◽  
Offshore Wind ◽  
Voltage Source ◽  
Future Research ◽  
Voltage Source Converter ◽  
Offshore Wind Farms ◽  
Multi Level ◽  
Level Converter

Theoretical review of various topologies of high voltage DC links in application to off shore wind forms has been studied and analysed. In addition to that, various types of high voltage DC links such as back to back, two terminal, multi-terminal systems has been covered under this study. The Line-Commutated Converters, Voltage Source Converter, Modular Multi-Level Converter as well as some of advanced hybrid high voltage DC topologies in application to off shore wind forms has been reviewed. This study covers complication arising from large-scale wind power generation. The review paper also points out the scope of future research in high voltage DC converters.

scholarly journals A Multi-Terminal HVdc Grid Topology Proposal for Offshore Wind Farms

2020 ◽  
Vol 10 (5) ◽  
pp. 1833
Author(s):  
Ali Raza ◽  
Muhammad Younis ◽  
Yuchao Liu ◽  
Ali Altalbe ◽  
Kumars Rouzbehi ◽  
...  
Keyword(s):  
High Voltage ◽  
Wind Farm ◽  
Wind Farms ◽  
Offshore Wind ◽  
Voltage Source ◽  
Voltage Source Converter ◽  
Offshore Platforms ◽  
Offshore Wind Farms ◽  
Dc Fault ◽  
Grid Side

Although various topologies of multi-terminal high voltage direct current (MT-HVdc) transmission systems are available in the literature, most of them are prone to loss of flexibility, reliability, stability, and redundancy in the events of grid contingencies. In this research, two new wind farms and substation ring topology (2WF-SSRT) are designed and proposed to address the aforementioned shortcomings. The objective of this paper is to investigate MT-HVdc grid topologies for integrating large offshore wind farms with an emphasis on power loss in the event of a dc grid fault or mainland alternating current (ac)grid abnormality. Standards and control of voltage source converter (VSC) based MT-HVdc grids are defined and discussed. High voltage dc switch-gear and dc circuit topologies are appraised based on the necessity of dc cables, HVdc circuit breakers, and extra offshore platforms. In this paper, the proposed topology is analyzed and compared with the formers for number and ratings of offshore substations, dc breakers, ultra-fast mechanical actuators, dc circuits, cost, flexibility, utilization, and redundancy of HVdc links. Coordinated operation of various topologies is assessed and compared with respect to the designed control scheme via a developed EMTDC/PSCAD simulation platform considering three fault scenarios: dc fault on transmission link connecting the wind farm to mainland power converters, dc fault within substation ring of VSC-HVdc stations, and ultimate disconnection of grid side VSC station. Results show that 2WF-SSRT is a promising topology for future MT-HVdc grids.

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

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.

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

Green ◽  
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.

Application of Offshore Concrete Constructions for Ocean Renewable Energy Storage (ORES)

2014 ◽  
Vol 521 ◽  
pp. 703-706 ◽  
Author(s):  
Wei Feng Li ◽  
Su Hua Ma ◽  
Xiao Dong Shen
Keyword(s):  
Renewable Energy ◽  
Energy Storage ◽  
Wind Farm ◽  
Wind Farms ◽  
Excess Energy ◽  
Offshore Wind ◽  
Offshore Wind Farm ◽  
Offshore Wind Farms ◽  
Ocean Renewable Energy ◽  
Renewable Energy Storage

Storage of energy generated by offshore wind farms still addresses one of the vexing problems inherent in offshore renewable energy such as offshore wind or solar energy how to store excess energy. Researchers tried to apply concrete in the energy storage of offshore wind farm recently, including the OTEC artificial energy islands, the MITS Ocean Renewable Energy Storage (ORES) and Belgiums energy atoll, and the progresses were reviewed.

scholarly journals Modelling the impact of offshore wind farms on safety radars onboard oil and gas platforms

2017 ◽  
Vol 11 (12) ◽  
pp. 1714-1718
Author(s):  
Laith Danoon ◽  
Waleed Al‐Mashhadani ◽  
Anthony Brown
Keyword(s):  
Oil And Gas ◽  
Wind Farms ◽  
Offshore Wind ◽  
Offshore Wind Farms ◽  
The Impact

scholarly journals COASTAL BATHYMETRY FROM SATELLITE AND ITS USE ON COASTAL MODELLING

2018 ◽  
pp. 98
Author(s):  
Rodolfo Bolaños ◽  
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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