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Offshore wind farms are great options for addressing the world's energy and climate change challenges, as well as meeting rising energy demand while taking environmental and economic impacts into account. Floating wind turbines, in specific, depict the next horizon in the sustainable renewable energy industry. In this study, a life-cycle cost analysis for floating offshore wind turbines is developed by combining the most recent data and parametric formulas from databases and relevant papers. The cost analysis models focused on cost minimization with special emphasis on Operation and Maintenance Cost (OPEX), Decommissioning Cost (DECOM), and Levelized Cost of Energy (LCOE), which are important factors in wind power economy. Given that floating wind energy is still developing, the presented scenarios should be beneficial in making future decisions. The cost analysis scenarios include on-site and off-site maintenance scenarios for OPEX. In addition, four alternative scenarios for DECOM have been examined: mechanical recycling, mechanical-incineration, incineration processes, and landfill. According to the findings of these scenarios, OPEX varies from 16.89 to 19.93 £/MWh and DECOM between 3.47 and 3.65 £/MWh, whilst the total LCOE varied from 50.67 to 66.73 £/MWh. [ABSTRACT FROM AUTHOR]

In recent years, the demand and requirement for renewable energy have significantly increased due to concerns regarding energy security and the climate crisis. This has led to a significant focus on wind power generation. As the deployment of wind turbines continues to rise, there is a growing need to assess their lifespan and improve their stability. Access to accurate load data is crucial for enhancing safety and conducting remaining life assessments of wind turbines. However, maintaining and ensuring the reliability of measurement systems for long-term load data accumulation, stability assessments, and residual life evaluations can be challenging. As a result, numerous studies have been conducted on load prediction for wind turbines. However, existing load prediction models based on 10 min statistical data cannot adequately capture the short-term load variations experienced by wind turbines. Therefore, it is essential to develop models capable of predicting load with a high temporal resolution to enhance reliability, especially with the increasing scale and development of floating wind turbines. In this paper, we developed prediction models with a 50 Hz resolution for the bending strain at the tower bottom of offshore wind turbines by combining SCADA data and acceleration data using machine learning techniques and analyzed the results. The load prediction models demonstrated high accuracy, with a mean absolute percentage error below 4%. [ABSTRACT FROM AUTHOR]

Considering the global socio-economic context, the pressure on natural resources and of course the effects that exploitation has on natural ecosystems and fauna is more and more evident. The use of renewable energy sources, together with improvements in energy efficiency, can help reduce energy consumption, reduce greenhouse gas emissions and, consequently, prevent dangerous climate change. The integration of renewable energy sources in urban areas and in everyday life is a viable solution. The present paper focuses on the presentation of small-scale wind systems integrated in urban areas and not only to capitalize any energy as efficiently as possible. [ABSTRACT FROM AUTHOR]

Governments worldwide are setting ambitious targets for renewable energy sources as a response to the ongoing climate crisis, leading to increased investment in offshore wind. While fixed wind structures have restrictive water depth limitations, floating devices are being developed to harness the resource in deeper waters. As part of this development, accurate prediction of ultimate loads and platform motions is crucial for survivability and cost-competitiveness. Present design standards rely on time-consuming methodologies based on irregular sea state data to determine design loads. 'Short design waves' are a potential solution to speed up the process by simulating short wave profiles that target extreme responses, bypassing the need for modelling long-duration irregular sea states. This paper explores the application of short design waves to semi-submersible wind platforms, and aims to determine whether extreme motions produced by these methods are comparable with current design practices. Short design waves show promise for surge and heave extremes, but further refinement is needed to improve pitch predictions and align with industry standards. Based on the present comparison, short design waves have potential within early design stages, where a wide range of environmental conditions are explored, but their reliability and applicability in alternative scenarios requires further investigation. • Short design wave (SDW) predictions of extreme motions of a semi-sub wind platform are explored. • Comparison is made with current design load standards based on 1-hour irregular sea state data. • Established design load methods using irregular sea states shown to be sensitive to random seeding. • Surge and heave predictions are good, but pitch needs improvement to align with industry standards. • SDWs have potential in early design stages to explore a wide range of environmental conditions. [ABSTRACT FROM AUTHOR]

Aiming at the problem of global climate change and energy crisis, wind power has become the focus of energy sustainable development in all countries. The wind turbines (WTs) power system is connected to the grid via the power electronic converter, causing the system inertia level to drop. In this paper, the direct-drive WT system is considered as the research object, and the whole-system frequency response model is established. The inertia and damping characteristics of the WT converter systems with virtual inertia control are analyzed. With the support of fan rotor kinetic energy and the energy saved in a capacitor, the simple control can also make the system exhibit different degrees of inertia and damping features. The results show that the equivalent inertia and the WT inertia time constant, capacitance parameters and virtual control parameters kd are related; the equivalent damping parameter is related to the steady-state operating point parameters and the virtual control parameter kp; the equivalent synchronization parameter is related to the steady-state operating point parameters and the virtual inertia control parameter ki. Finally, the correctness of the inertial and damping characteristics of the WT grid-connected system is verified by simulation, which provides a theoretical reference for studying the inertial damping of power electronic dominant systems. [ABSTRACT FROM AUTHOR]

As a response to the threat of climate change, many nations are increasing their use of renewable energy, including wind energy. Large wind farms often conflict with other land uses, particularly tourism, which is a growing industry worldwide. In Iceland, tourism has recently become the largest export sector, with majority of tourists travelling to the country to experience its nature. This paper examines tourists' opinions and perceptions of wind power development in the Southern Highlands of Iceland and compares how number, size and proximity of wind turbines, and the landscape in which they are situated, influence tourists' perceptions. The study is based on an on-site questionnaire survey conducted in 2015. The results indicate that one-third of the travellers would be less likely to visit the Southern Highlands if a proposed wind farm were built, and two-thirds think that wind turbines would decrease the area's attractiveness. [ABSTRACT FROM AUTHOR]

Renewable energy is crucial for addressing energy security and climate change challenges. Offshore wind energy presents a significant opportunity to generate renewable energy. Shallow water areas, between 50 and 70 m deep, are economically feasible for wind farms using shared anchor concepts and mooring line systems. However, choosing the appropriate type of system is critical. Previous studies have demonstrated that synthetic fiber ropes are more efficient than traditional chain catenary. In this paper we present the results of a dynamic analysis of a 15 MW Turbine and the VolturnUS-S reference platform deployed in the Celtic Sea. We compare the planar displacements, rotations, and loads acting on a shared anchor using nylon and polyester ropes, the latter as retrieved from the literature. An engineering procedure is used to simulate the behavior of the nylon rope, and a diffraction analysis is employed considering the stiffness of the mooring matrix. Our results show that using nylon rope reduces the peak resolved anchor load by 44% compared to polyester, but at the cost of a relatively larger displacements and rotations, which can be mitigated with improvements in mooring design. Since nylon is 10% cheaper than polyester rope with an identical minimum breaking load (MBL), and more cost-efficient anchor concepts are being investigated, the findings of this study encourage further research on nylon applications for wind farms in shallow water using shared anchors. • Nylon mooring components are investigated for the floating IEA 15 MW wind turbine. • Nylon rope can reduce anchor loads at the cost of large displacement and rotation. • Nylon rope and anchor shared concepts can be the most cost-efficient solution for shallow waters. [ABSTRACT FROM AUTHOR]

The deployment of onshore wind power is an important means to mitigate climate change. However, wind turbines also have negative impacts at the local scale, like disamenities to residents living nearby, changes in landscape quality, or conflicts with nature conservation. Our paper quantifies spatial trade-offs arising between these criteria. For this purpose, we propose a novel approach using Pareto frontiers and a Gini-like potential trade-off indicator. Our analysis builds on a spatial optimization model using geographical information system data for Germany. We show that spatial trade-offs between the criteria under consideration are substantial. The size of the trade-off varies substantially with the criteria under consideration, depending on the spatial heterogeneity of each criterion as well as on the spatial correlation between the criteria. Spatial trade-offs are particularly pronounced between nature conservation (measured by impacts on wind power-sensitive birds) and other criteria. [ABSTRACT FROM AUTHOR]

With the abundance of wind resources in cold climates, a significant share of the worldwide wind energy installed capacity is located in those areas. However, the advantages of cold climate operation comes with challenges associated with ice accretion. Throughout the years, alternative operational strategies have been developed to cope with these challenges. Although many strategies, such as blade heating, have been commercially available for a long time, few field studies have investigated their performance. Evaluating the performance of wind turbines in cold climates is a hard task due to the lack standards and the variability of external factors influencing turbine behaviour. In this paper, a methodology to assess the performance of wind turbines in cold climates is illustrated with a case study. This methodology aims to provide a better understanding of how ice accretion impacts wind turbine performance. This methodology was exemplified with a case study where the performance of a turbine equipped with a retrofit hot air ice protection system was analyzed over a 9-day icing event. It was found that the usage of the cold climate solution yielded an average energy gain of 159 MWh and an average potential recovery of 62%. • Proposition of a methodology for assessing the performance of cold climate solutions for wind turbines. • Description of the process of power curve modelling, selection of control turbines and interpretation of icing events. • Case study of a 9-day icing event where the performance of a turbine with an ice protection system is analyzed. [ABSTRACT FROM AUTHOR]

The European Strategic Energy Technology Plan, adopted by the European Union in 2008, is a first step to establish an energy technology policy for Europe and to support the 2020 energy and climate change targets from the technology development point of view. One of its initiatives is to assess the characteristics of the materials that will be needed in order to achieve the 2020 targets, in terms both of amounts of materials and their technical specifications, along with the way to get there for the latter. The Materials Initiative was created to foster a roadmap which is based on a scientific assessment of the current situation. This paper presents the work of the author in the (wind turbine) electricity generator part of that assessment, it includes the aspects of technology and system state-of-the-art; material supply status; on-going research and players; materials specification targets for 2020/2030 and beyond. The assessment found that the performance of permanent magnets is the single item potentially to provide the most significant improvement in component specification, but that in order to achieve this perhaps new chemical components –based on rare earths, as currently, or not-will be necessary in order to achieve these high-performance magnets. The search for these new materials is stimulated by the current dependency of the world in a nearly-monopolistic supplier of rare earth elements. The assessment also concluded that the improvement of materials specifications is challenging but achievable in most areas, and a crucial aspect for the necessary cost reductions in wind energy production. [ABSTRACT FROM AUTHOR]

The wind energy sector is one of the most prominent sectors of the renewable energy industry. However, its dependence on meteorological factors subjects it to climate change. Studies analysing the impact of climate change on wind resources usually only model changes in wind speed. Two elements that have to be calculated in addition to wind speed changes are Annual Energy Production (AEP) and Power Density (PD). This is not only because of the inherent variability between wind speed and wind power generated, but also because of the relative magnitudes of change in energy potentially generated at different areas under varied wind climates. In this study, it was assumed that two separate locations would experience a 10% wind speed increase after McInnes et al. (2010). Given the two locations' different wind speed distributions, a wind speed increase equal in magnitude is not equivalent to similar magnitudes of change in potential energy production in these areas. This paper demonstrates this fact for each of the case studies. It is of general interest to the energy field and is of value since very little literature exists in the Southern African context on climate change- or variability-effects on the (wind) energy sector. Energy output is therefore dependent not only on wind speed, but also wind turbine characteristics. The importance of including wind power curves and wind turbine generator capacity in wind resource analysis is emphasised. [ABSTRACT FROM AUTHOR]

Abstract: Wind energy, commonly recognized to be a clean and environmentally friendly renewable energy resource that can reduce our dependency on fossil fuels, has developed rapidly in recent years. Its mature technology and comparatively low cost make it promising as an important primary energy source in the future. However, there are potential environmental impacts due to the installation and operation of the wind turbines that cannot be ignored. This paper aims to provide an overview of world wind energy scenarios, the current status of wind turbine development, development trends of offshore wind farms, and the environmental and climatic impact of wind farms. The wake effect of wind turbines and modeling studies regarding this effect are also reviewed. [Copyright &y& Elsevier]

Abstract: In the last century, several climate changes have been observed in regions all over the world. The main cause of these climatic changes is the rise of fossil fuel uses, which is due to the important demographic and industrial development. These negative effects have forced scientists to draw attention to renewable energy sources, which are the most suitable solution in the future. In this paper, wind energy potential was estimated using the wind speed data collected by two meteorological stations installed in the Centre of Research and Technologies of Energy (CRTEn) in the Borj-Cedria area. The data collected at 30, 20 and 10m height during 2008 and 2009, have permitted us to estimate the seasonal mean wind speed, wind speed distribution and wind power density. The results have been used to estimate the net energy output of seven 1.5MW wind turbines with taken account the air density correction and the power losses in wind farm. This comparative simulation shows difference in wind generators production and allows us to choose the best wind turbine adapted to the site conditions. [Copyright &y& Elsevier]

Abstract: Climate change and limited primary energy resources require indigenous renewable electricity generation options to change the current coal-dominated power source matrix in China. The wind power is such a solution for the above challenges, and it still has large space for improvement in China. In this paper several critical factors related to Chinese wind power were studied in details, including the wind resources, the wind turbine industry and the policies from the Chinese government. Based on the study, the perspective of wind power in China was discussed. With outstanding advantages, the offshore wind power has a bright future in China, so its main characteristics are discussed. Based on the discussions, suggestions were given to improve the development of Chinese wind power, and the government''s further measures are also recommended. [Copyright &y& Elsevier]

Wind power is becoming an increasingly attractive method of electric power generation due to concerns with global climate change, increasing uncertainty of future oil supplies, and energy security. While most large-scale wind turbines are part of wind farms, which help states meet state renewable energy standards, several colleges and universities in the United States have purchased wind turbines for financial and educational purposes. This paper gives details of a cost-benefit analysis completed for a small liberal arts college in Illinois, Principia College, which is considering buying a single large-scale turbine. The process set forth here can easily be adapted to any college, university, or school. It is found that the project has a positive net present value for both a 20-year scenario and a 30-year scenario. Assuming the project did not receive any grants, Principia College would need to have an annual real return rate of about 6% on its initial investment to gain the same economic benefits. [ABSTRACT FROM AUTHOR]

In order to mitigate global climate change and air pollution, the Chinese government has assigned high priority to expanding low-carbon power generation in China. Recent studies have shown that wind power is one of the most promising renewable energy option in China. Although many studies have estimated the generation potential of onshore wind power, their results vary widely from 1783 TWh to 39,000 TWh. Therefore, we examine the different assumptions in these papers and identify three main factors influencing the results. The three influencing factors are: weather data set, land utilisation factor, and wind turbine configuration. For our model-based analysis, we define a reference scenario which is used to compare the results. Our analysis shows using a different weather data set increases the generation potential to roughly 35,000 TWh. This is 54% higher than the generation potential of the reference scenario. The land utilisation factor also has a large influence, ranging between −10% and −51%. The studies' assumptions and data should be subjected to careful scrutiny, as the calculated wind power potentials are widely used to develop decarbonisation strategies for the energy system. • Study results on wind power potentials in China vary from 1783 TWh to 39,000 TWh • Influencing factors: weather data set, land utilisation, and wind turbine configuration. • Model-based sensitivity analysis with nine scenario settings. • Chosen weather data set has the highest impact on the calculated results with a variation of 54%. [ABSTRACT FROM AUTHOR]

Wind power, as a renewable energy for coping with global climate change challenge, has achieved rapid development in recent years. The breakdown of wind turbines (WTs) not only leads to high repair expenses but also may threaten the stability of the whole power grid. How to reduce the operation and the maintenance (O&M) cost of wind farms is an obstacle to its further promotion and application. To provide reliable condition monitoring and fault diagnosis (CMFD) for WTs, this paper presents a comprehensive survey of the existing CMFD methods in the following three aspects: energy flow, information flow, and integrated O&M system. Energy flow mainly analyzes the characteristics of each component from the angle of energy conversion of WTs. Information flow is the carrier of fault and control information of WT. At the end of this paper, an integrated WT O&M system based on electrical signals is proposed. [ABSTRACT FROM AUTHOR]