scholarly journals ENHANCING MARINE ENERGY COMPETITIVENESS: CO-LOCATED OFFSHORE WIND AND WAVE ENERGY FARMS

2017 ◽  
pp. 4
Author(s):  
Sharay Astariz ◽  
Gregorio Iglesias
Keyword(s):  
Wave Energy ◽  
Wind Farm ◽  
Fossil Fuels ◽  
Sustainable Use ◽  
Wind Farms ◽  
Economic Benefits ◽  
Offshore Wind ◽  
Maintenance Cost ◽  
Shadow Effect ◽  
Marine Energy

If marine energy is to become a viable alternative to fossil fuels, its competitiveness must be enhanced. In this sense, combining various renewables in the same marine space is emerging as a solution. Among the different options, this paper focuses on combined wind and wave energy farms. First, the different synergies between both renewable are analysed, such as the more sustainable use of the marine resource or the opportunity to reduce costs of both technologies by sharing some of the most important costs of an offshore project. Second, this paper focuses on two technology synergies: the reduction of the inherent intermittency of renewables; and the so-called shadow effect which implies the reduction of the wave height in the inner part of the wind farm. Both effects may suppose an important reduction in the operation and maintenance cost by reducing the balancing cost when connecting the installation to the grid and increasing weather windows to access the wind turbines. However, the benefits of this combination will depend on the site characteristics and the array layout. On this basis, the power smoothing and shadow effect in co-located farms are analysed through different case studies considering real sea conditions, wind farms currently in operation and a high resolution numerical model (SWAN). Finally, conclusions about the economic benefits of co-located farms are drawn by recalculating the levelised cost of energy when both renewable are combined.

scholarly journals Wind and wave energy resource of Germany reported by ERA-Interim reanalysis data

2019 ◽  
Vol 122 ◽  
pp. 04003
Author(s):  
Eugen Rusu ◽  
Florin Onea
Keyword(s):  
Wave Energy ◽  
Energy Resource ◽  
Wind Farms ◽  
Reanalysis Data ◽  
Offshore Wind ◽  
Time Interval ◽  
Offshore Wind Farms ◽  
The North ◽  
Marine Energy ◽  
Suitable Area

The aim of this work is to identify the most suitable offshore wind farms from Germany that present relevant wave conditions, suitable for the development of a wave energy project. By using the ERA-Interim data (wind and waves) reported for the time interval from 1999 and 2018, was possible to identify the more important areas, by taking also into account the seasonal distributions. Several wave energy converters were considered for assessment, for which a capacity factor located between 2.5% and 14% was reported, better results being accounted by the Seabased system (rated at 15 kW). Finally, we canconcluded that the North Sea represent an important area in terms of the marine energy and since at this moment there are operational wave projects, this will represent a suitable area for the development of a mixed wind-wave project.

scholarly journals Research on a Comprehensive Maintenance Optimization Strategy for an Offshore Wind Farm

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 965
Author(s):  
Yang Lu ◽  
Liping Sun ◽  
Yanzhuo Xue
Keyword(s):  
Wind Farm ◽  
Wind Farms ◽  
Weather Conditions ◽  
Offshore Wind ◽  
Monte Carlo Algorithm ◽  
Maintenance Cost ◽  
Offshore Wind Turbine ◽  
Offshore Wind Farm ◽  
Proposed Model ◽  
Maintenance Activities

Offshore wind is considered a crucial part in the future energy supply. However, influenced by weather conditions, the maintenance of offshore wind turbine system (OWTs) equipment is challenged by poor accessibility and serious failure consequences. It is necessary to study the optimized strategy of comprehensive maintenance for offshore wind farms, with consideration of the influences of incomplete equipment maintenance, weather accessibility and economic relevance. In this paper, a Monte Carlo algorithm-improved factor is presented to simulate the imperfect preventive maintenance activity, and waiting windows were created to study the accessibility of weather conditions. Based on a rolling horizon approach, an opportunity group maintenance model of an offshore wind farm was proposed. The maintenance correlations between systems and between equipment as well as breakdown losses, maintenance uncertainty, and weather conditions were taken into account in the model, thus realizing coordination of maintenance activities of different systems and different equipment. The proposed model was applied to calculate the maintenance cost of the Dafengtian Offshore Wind Farm in China. Results proved that the proposed model could realize long-term dynamic optimization of offshore wind farm maintenance activities, increase the total availability of the wind power system and reduce total maintenance costs.

scholarly journals Optimal scheduling of the next preventive maintenance activity for a wind farm

2021 ◽  
Vol 6 (3) ◽  
pp. 949-959
Author(s):  
Quanjiang Yu ◽  
Michael Patriksson ◽  
Serik Sagitov
Keyword(s):  
Wind Turbine ◽  
Optimization Model ◽  
Preventive Maintenance ◽  
Wind Farm ◽  
Linear Optimization ◽  
Wind Farms ◽  
Offshore Wind ◽  
Computational Time ◽  
Maintenance Cost ◽  
Component System

Abstract. A large part of the operational cost for a wind farm is due to the cost of equipment maintenance, especially for offshore wind farms. How to reduce the maintenance cost, and hence increase profitability, is this article's focus. It presents a binary linear optimization model whose solution may inform the wind turbine owners about which components, and when, should undergo the next preventive maintenance (PM) replacements. The suggested short-term scheduling strategy takes into account eventual failure events of the multi-component system – in that after the failed system is repaired, the previously scheduled PM plan should be updated, assuming that the restored components are as good as new. The optimization algorithm of this paper, NextPM, is tested through numerical case studies applied to a four-component model of a wind turbine. The first study addresses the important case of a single component system, used for parameter calibration purposes. The second study analyses the case of seasonal variations of mobilization costs, as compared to the constant mobilization cost setting. Among other things, this analysis reveals a 35 % cost reduction achieved by the NextPM model, as compared to the pure corrective maintenance (CM) strategy. The third case study compares the NextPM model with another optimization model – the preventive maintenance scheduling problem with interval costs (PMSPIC), which was the major source of inspiration for this article. This comparison demonstrates that the NextPM model is accurate and much faster in terms of computational time.

scholarly journals Pathways to bring the costs down of floating offshore wind farms in the Atlantic Area

2019 ◽  
Author(s):  
Juan José Cartelle-Barros ◽  
David Cordal-Iglesias ◽  
Eugenio Baita-Saavedra ◽  
Almudena Filgueira-Vizoso ◽  
Bernardino Couñago-Lorenzo ◽  
...  
Keyword(s):  
Power Plants ◽  
Wind Farm ◽  
Fossil Fuels ◽  
Net Present Value ◽  
Wind Farms ◽  
Offshore Wind ◽  
Electricity Production ◽  
Offshore Wind Farm ◽  
Offshore Wind Farms ◽  
Atlantic Area

Abstract. Every nations' development lies on the electricity production, since it facilitates life and development of their society (heating, lighting, etc.). Nevertheless, conventional power plants, which use fossil fuels, cause environmental impacts, such as global warming, acidification, eutrophication, among many others. In addition, these conventional resources generate a dependence of external providers, which obstructs the progress of the developing countries. Renewable energies came to solve part of these problems. In this context, wind energy is one the technologies with more expansion all over the world. Offshore locations have a better wind resource than onshore ones and their exploitation is lower. The objective of this work is to present a holistic approach to assess the feasibility of a floating offshore wind farms in a life cycle perspective. The methodology proposed analyses the Net Present Value, the Internal Rate of Return, the Payback Period and the Levelized Cost of Energy of the farm. The case study is built based on a disruptive floating spar-type platform called TELWIND®, to be implemented in the Atlantic Area region. Results indicate how important these parameters are in economic terms and shows the pathways to reduce the costs of this type of infrastructures Furthermore, the methodology proposed allows the selection of the best region where a floating offshore wind farm can be installed. Finally, this study can be useful for Governments and relevant authorities to determine the best location of a floating offshore wind farm and develop the roadmap of offshore wind in their country.

scholarly journals Reducing Operational Costs of Offshore HVDC Energy Export Systems Through Optimized Maintenance

Energies ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1146
Author(s):  
Jan Frederick Unnewehr ◽  
Hans-Peter Waldl ◽  
Thomas Pahlke ◽  
Iván Herráez ◽  
Anke Weidlich
Keyword(s):  
Wind Farm ◽  
Wind Farms ◽  
Offshore Wind ◽  
Maintenance Cost ◽  
Energy Yield ◽  
Offshore Wind Farms ◽  
Maintenance Costs ◽  
Operational Costs ◽  
Depth Analysis ◽  
Maintenance Work

For the grid connection of offshore wind farms today, in many cases a high-voltage direct current (HVDC) connection to the shore is implemented. The scheduled maintenance of the offshore and onshore HVDC stations makes up a significant part of the operational costs of the connected wind farms. The main factor for the maintenance cost is the lost income from the missing energy yield (indirect maintenance costs). In this study, we show an in-depth analysis of the used components, maintenance cycles, maintenance work for the on- and offshore station, and the risks assigned in prolonging the maintenance cycle of the modular multilevel converter (MMC). In addition, we investigate the potential to shift the start date of the maintenance work, based on a forecast of the energy generation. Our findings indicate that an optimized maintenance design with respect to the maintenance behavior of an HVDC energy export system can decrease the maintenance-related energy losses (indirect maintenance costs) for an offshore wind farm to almost one half. It was also shown that direct maintenance costs for the MMC (staff costs) have small effect on the total maintenance costs. This can be explained by the fact that the additional costs for maintenance staff are two orders of magnitude lower than the revenue losses during maintenance.

scholarly journals Dynamic Modeling of an Offshore Floating Wind Turbine for Application in the Mediterranean Sea

Energies ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 248
Author(s):  
Lorenzo Cottura ◽  
Riccardo Caradonna ◽  
Alberto Ghigo ◽  
Riccardo Novo ◽  
Giovanni Bracco ◽  
...  
Keyword(s):  
Wind Turbine ◽  
Mediterranean Sea ◽  
Wind Farm ◽  
Reference Model ◽  
Wide Spectrum ◽  
Wind Farms ◽  
Offshore Wind ◽  
Floating Wind Turbine ◽  
The Mediterranean ◽  
Offshore Floating Wind Turbine

Wind power is emerging as one of the most sustainable and low-cost options for energy production. Far-offshore floating wind turbines are attractive in view of exploiting high wind availability sites while minimizing environmental and landscape impact. In the last few years, some offshore floating wind farms were deployed in Northern Europe for technology validation, with very promising results. At present time, however, no offshore wind farm installations have been developed in the Mediterranean Sea. The aim of this work is to comprehensively model an offshore floating wind turbine and examine the behavior resulting from a wide spectrum of sea and wind states typical of the Mediterranean Sea. The flexible and accessible in-house model developed for this purpose is compared with the reference model FAST v8.16 for verifying its reliability. Then, a simulation campaign is carried out to estimate the wind turbine LCOE (Levelized Cost of Energy). Based on this, the best substructure is chosen and the convenience of the investment is evaluated.

Monitoring fisheries resources at offshore wind farms: BACI vs. BAG designs

2020 ◽  
Vol 77 (3) ◽  
pp. 890-900
Author(s):  
Elizabeth T Methratta
Keyword(s):  
Statistical Power ◽  
Wind Farm ◽  
Wind Farms ◽  
Offshore Wind ◽  
Cultural Value ◽  
Analytical Models ◽  
Offshore Wind Farms ◽  
Fisheries Resources ◽  
Unaffected Control ◽  
Before And After

Abstract Offshore wind farms often co-occur with biodiverse marine ecosystems with high ecological, economic, and cultural value. Yet there are many uncertainties about how wind farms affect marine organisms and their environment. The before–after–control–impact (BACI) design, an approach that compares an impact location with an unaffected control both before and after the intervention, is the most common method used to study how offshore wind farms affect finfish. Unfortunately, this design has several methodological limitations that undermine its ability to detect effects in these studies. An alternative approach, the before–after-gradient (BAG) design, would sample along a gradient with increasing distance from the turbines both before and after the intervention, and could overcome many of the limitations of BACI. The BAG design would eliminate the difficult task of finding a suitable control, allow for the assessment of the spatial scale and extent of wind farm effects, and improve statistical power by incorporating distance as an independent variable in analytical models rather than relegating it to the error term. This article explores the strengths and weaknesses of the BACI and BAG designs in the context of offshore wind development and suggests an approach to incorporating the BAG design into existing fisheries surveys and a regional monitoring framework.

scholarly journals Analysis of offshore wind farm located on Baltic Sea

2019 ◽  
Vol 137 ◽  
pp. 01049
Author(s):  
Anna Sobotka ◽  
Kajetan Chmielewski ◽  
Marcin Rowicki ◽  
Justyna Dudzińska ◽  
Przemysław Janiak ◽  
...  
Keyword(s):  
Baltic Sea ◽  
Wind Farm ◽  
Wind Farms ◽  
Offshore Wind ◽  
The European Union ◽  
European Union Policy ◽  
Offshore Wind Farms ◽  
Wind Speeds ◽  
Wind Measurements ◽  
The Baltic

Poland is currently at the beginning of the energy transformation. Nowadays, most of the electricity generated in Poland comes from coal combustion. However, in accordance to the European Union policy of reducing the emission of carbon dioxide to the atmosphere, there are already plans to switch to low-emission energy sources in Poland, one of which are offshore wind farms. The article presents the current regulatory environment of the offshore wind energy in Poland, along with a reference to Polish and European decarbonisation plans. In the further part of the article, the methods of determining the kinetic energy of wind and the power curve of a wind turbine are discussed. Then, on the basis of historical data of wind speeds collected in the area of the Baltic Sea, calculations are carried out leading to obtain statistical distributions of power that could be generated by an exemplary wind farm with a power capacity of 400 MW, located at the place of wind measurements. On their basis, statistical differences in the wind power generation between years, months of the year and hours of the day are analysed.

An Extended Pattern Search Method for Offshore Floating Wind Layout and Turbine Geometry Optimization

2016 ◽  
Author(s):  
Caitlin Forinash ◽  
Bryony DuPont
Keyword(s):  
Wind Farm ◽  
Cost Model ◽  
Geometry Optimization ◽  
Interaction Model ◽  
Solution Space ◽  
Wind Farms ◽  
Power Production ◽  
Pattern Search ◽  
Offshore Wind ◽  
Extended Pattern Search

An Extended Pattern Search (EPS) method is developed to optimize the layout and turbine geometry for offshore floating wind power systems. The EPS combines a deterministic pattern search with stochastic extensions. Three advanced models are incorporated: (1) a cost model considering investment and lifetime costs of a floating offshore wind farm comprised of WindFloat platforms; (2) a wake propagation and interaction model able to determine the reduced wind speeds downstream of rotating blades; and (3) a power model to determine power produced at each rotor, and includes a semi-continuous, discrete turbine geometry selection to optimize the rotor radius and hub height of individual turbines. The objective function maximizes profit by minimizing cost, minimizing wake interactions, and maximizing power production. A multidirectional, multiple wind speed case is modeled which is representative of real wind site conditions. Layouts are optimized within a square solution space for optimal positioning and turbine geometry for farms containing a varying number of turbines. Resulting layouts are presented; optimized layouts are biased towards dominant wind directions. Preliminary results will inform developers of best practices to include in the design and installation of offshore floating wind farms, and of the resulting cost and power production of wind farms that are computationally optimized for realistic wind conditions.

A Study on the New Grid Integration Solutions of Offshore Wind Farms

2011 ◽  
Vol 383-390 ◽  
pp. 3610-3616 ◽  
Author(s):  
Xin Yin Zhang ◽  
Zai Jun Wu ◽  
Si Peng Hao ◽  
Ke Xu
Keyword(s):  
Wind Farm ◽  
Wind Farms ◽  
Offshore Wind ◽  
Grid Integration ◽  
Variable Speed ◽  
Reliable Operation ◽  
Offshore Wind Farms ◽  
Electrical Interconnection ◽  
Investment Cost ◽  
And Performance

Offshore wind farm is developed in the ascendant currently. The reliable operation, power loss, investment cost and performance of wind farms were effect by the integration solutions of electrical interconnection system directly. Several new integration configurations based on VSC-HVDC were comparative analyzed. For the new HVDC topology applied the wind farm internal DC bus, the Variable Speed DC (VSDC) system that is suitable for those topologies was proposed. The structure of VSDC was discussed and maximum wind power tracking was simulated on the minimal system. It is clear that new integration configurations based on VSC-HVDC has good prospects.

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