Search Results (217)

Currently, Poland is witnessing a dynamic development of the offshore wind energy sector, which will be a key component of the national energy mix. While many international studies have addressed wind energy deployment, there is a lack of research that compares the energy and economic performance of both onshore and offshore wind farms under Polish climatic and spatial conditions, especially in relation to turbine spacing optimization. This study addresses that gap by performing a computer-based simulation analysis of three onshore spacing variants (3D, 4D, 5D) and four offshore variants (5D, 6D, 7D, 9D), located in central Poland (Stęszew, Okonek, Gostyń) and the Baltic Sea, respectively. The efficiency of wind farms was assessed in both energy and economic terms, using WAsP Bundle software and standard profitability evaluation metrics (NPV, MNPV, IRR). The results show that the highest NPV and MNPV values among onshore configurations were obtained for the 3D spacing variant, where the energy yield leads to nearly double the annual revenue compared to the 5D variant. IRR values indicate project profitability, averaging 14.5% for onshore and 11.9% for offshore wind farms. Offshore turbines demonstrated higher capacity factors (36–53%) compared to onshore (28–39%), with 4–7 times higher annual energy output. The study provides new insight into wind farm layout optimization under Polish conditions and supports spatial planning and investment decision making in line with national energy policy goals. Full article

The series-connected DRU-MMC hybrid converter, with its compact size and cost-effectiveness, presents an attractive solution for long-distance offshore wind power transmission. However, its application is limited by the DRU’s unidirectional power flow and the voltage mismatch between the auxiliary MMC and the onshore MMC during black-start operations. To overcome these challenges, a four-stage black-start strategy utilizing an auxiliary step-down transformer connected to the onshore MMC is proposed. The proposed strategy operates as follows: The onshore MMC first lowers its valve-side voltage via an auxiliary transformer, enabling reduced DC-side voltage. With the DRU bypassed, the offshore MMC draws startup power through the DC link, then switches to V/f mode with wind turbine curtailment to reduce DC current below the DRU bypass threshold. After stable, low-power operation, the DRU is integrated. The onshore MMC then restores rated DC voltage and disconnects the transformer, allowing gradual wind turbine reconnection to complete black-start. The simulation results confirm the approach’s feasibility under conditions where all wind turbines operate in grid-following mode. Full article

Driven by the demands of climate change mitigation, many countries have begun large-scale electricity production from variable renewables, such as solar PV and wind power. Electricity production from wind turbines, in particular, strongly depends on local weather conditions and their changes caused by climate change. Thus, for many countries with a high share of wind power generation, such as Germany, two essential questions arise: how will climate change affect electricity production, and how strong will be this impact for different RCPs? To better assess the impact on existing onshore wind turbines, spatially and temporally resolved data on their power generation are required. In order to create such disaggregated data, this study uses a physical simulation model and climate data modified for the RCP 2.6, RCP 4.5, and RCP 8.5 scenarios. To investigate the effects on a significant region with very high wind power generation in Germany, the numerical simulations were carried out on an ensemble of 22 onshore wind turbines with an installed capacity of 65.5 MW in the German Bight. After model validation, the power generation from this turbine ensemble was simulated for the high-wind year 2008 and the low-wind year 2010. The simulation results are presented with a high temporal resolution, and the observed changes are discussed for the applied RCPs. In summary, the resulting wind power generation of the entire plant ensemble decreases with increasing RCP to values of up to nearly 3 GWh for both years. Full article

Brazil has emerged as one of the global leaders in adopting renewable energy, standing out in the implementation of onshore wind energy and, more recently, in the development of future offshore wind energy projects. Onshore wind energy has experienced exponential growth in the last decade, positioning Brazil as one of the countries with the largest installed capacity in the world by 2023, with 30 GW. Wind farms are mainly concentrated in the northeast region, where winds are constant and powerful, enabling efficient and cost-competitive generation. Although in its early stages, offshore wind energy presents significant potential of 1228 GW due to Brazil’s extensive coastline, which exceeds 7000 km. Offshore wind projects promise greater generating capacity and stability, as offshore winds are more constant than onshore winds. However, their development faces challenges such as high initial costs, environmental impacts on marine ecosystems, and the need for specialized infrastructure. From a sustainability perspective, this article discusses that both types of wind energy are key to Brazil’s energy transition. They reduce dependence on fossil fuels, generate green jobs, and foster technological innovation. However, it is crucial to implement policies that foster synergy with green hydrogen production and minimize socio-environmental impacts, such as impacts on local communities and biodiversity. Finally, the article concludes that by 2050, Brazil is expected to consolidate its leadership in renewable energy by integrating advanced technologies, such as larger, more efficient turbines, energy storage systems, and green hydrogen production. The combination of onshore and offshore wind energy and other renewable sources could position the country as a global model for a clean, sustainable, and resilient energy mix. Full article

The increasing penetration of wind power—driven by the expansion of offshore projects and the repowering of existing onshore installations—poses novel challenges for power system operators. While wind energy is currently integrated without curtailment and considered fully dispatchable, its inherent variability introduces growing concerns due to its rising share in installed capacity relative to conventional sources. In Portugal, wind energy already accounts for approximately 30% of the total installed capacity, with projections reaching 38% by 2030, making it the country’s second largest energy source. In the context of the 2050 carbon neutrality targets, quantifying and managing wind power uncertainty has become increasingly important. This study proposes an integrated methodology to analyze and compare the uncertainty of onshore and offshore wind generation using real-world high-resolution data (15 min intervals over a three-year period) from three onshore and one offshore wind turbine. The framework combines statistical characterization, probabilistic modeling with zero-inflated distributions, entropy-based uncertainty quantification (using Shannon, Rényi, Tsallis, and permutation entropy), and an uncertainty-adjusted Levelized Cost of Energy (LCOE). The results show that although offshore wind energy involves higher initial investment, its lower temporal variability and entropy levels contribute to superior economic reliability. These findings highlight the relevance of incorporating uncertainty into economic assessments, particularly in electricity markets where producers are exposed to penalties for deviations from scheduled generation. The proposed approach supports more informed planning, investment, and market strategies in the transition to a renewable-based energy system. Full article

Wind power plays a pivotal role in the achievement of carbon peaking and carbon neutrality. Extensive evidence has demonstrated that there are adverse impacts of wind power expansion on natural ecosystems, particularly on forests, such as forest degradation and habitat loss. However, incomplete and outdated information regarding onshore wind turbines in China hinders further systematic and in-depth studies. To address this challenge, we compiled a geospatial dataset of wind turbines located in forest areas of China as of 2022 to enhance data coverage from publicly available sources. Utilizing the YOLOv10 framework and high-resolution Jilin-1 optical satellite images, we identified the coordinates of 63,055 wind turbines, with an F1 score of 97.64%. Our analysis indicated that a total of 16,173 wind turbines were situated in forests, primarily within deciduous broadleaved forests (44.17%) and evergreen broadleaved forests (31.82%). Furthermore, our results revealed significant gaps in data completeness and balance in publicly available datasets, with 48.21% of the data missing and coverage varying spatially from 28.96% to 74.36%. The geospatial dataset offers valuable insights into the distribution characteristics of wind turbines in China and could serve as a foundation for future studies. Full article

When wind turbines operate in high-latitude offshore regions, ice accumulation on blade surfaces can severely compromise the structural safety of turbines and reduce their power generation efficiency. To mitigate the adverse effects of ice accumulation on wind turbines, it is essential to evaluate the effectiveness of various anti-icing measures in offshore environments. Superhydrophobic materials, known for their environmental friendliness, high efficiency, and energy-saving advantages, have been widely used for anti-icing in onshore wind power generation. However, their direct application to offshore wind turbines is limited due to the presence of salt in offshore environments. In this study, laboratory-scale experiments were conducted to investigate the anti-icing performance of superhydrophobic surfaces under winter atmospheric conditions simulating China’s Bohai Sea. The experiments were divided into two phases. In the first phase, the ice accretion process and morphology of superhydrophobic surfaces were analyzed under different operating conditions. The second phase expanded on the first by further examining the icing process of droplets on these surfaces. The results indicate that both the salt content and wind speed significantly affect the anti-icing performance of superhydrophobic surfaces. Additionally, the salt content influences the critical droplet diameter required for detachment. This research provides insights into icing mechanisms and supports the development of anti-icing technologies for offshore wind turbine blades with superhydrophobic surfaces. Full article

The article contains an analysis of power generation by a photovoltaic system with a peak power of 3 MWp and a wind turbine with a power of 3.45 MW. The acquired time series of generated power was analyzed using traditional and modern analytical methods. The power generated by these two Renewable Energy Sources was characterized separately and then by their mix. In this article, the power signature was defined as the power generated by the photovoltaic system and the wind turbine in the state space over a period of one month. The state space was extracted from the results of cluster analysis. The experiment with clustering was carried out into 10 classes. The K-Means clustering algorithm was used to determine the clusters in a variant without prior labeling of classes with the method of learning without the participation of the teacher. In this way, the trajectories of the power generation process from two Renewable Energy Sources were determined in the 10-state space. Knowing which class each data record belongs to, the frequencies of staying in each state were determined. The computational algorithm presented in the article may have great practical application in balancing the power grid powered by energy produced from renewable sources. Full article

The aim of the article is to provide recommendations for the implementation of sustainable management principles into the practice of various companies operating in the onshore wind energy industry. The desk research method was used in the study, as well as free interviews which were conducted with 30 people who are directly concerned with the issues related to the expansion of the wind farm network—they live in or plan to move to the vicinity of wind farms. The results obtained show that onshore wind energy should not be perceived solely through the prism of the sustainable operation of turbines and wind farms. As the interviews with the interlocutors showed, wind energy has also disadvantages and is a source of threats. The authors believe that the full sustainability of the wind energy industry will only occur when all economic entities, both directly and indirectly related to this sector, i.e., those involved in the design, production, transport, assembly, operation, supervision, and decommissioning of wind turbines, implement the goals of sustainable development by implementing systemic management solutions into their practice. This will be facilitated by the model approach to sustainable management presented in this article. In this context, the article contributes to the theory of sustainable development and management. It has also a practical value. There are specific solutions indicated that will facilitate the transformation of companies currently operating in the onshore wind energy industry into their fully sustainable counterparts. Their usage and implementation in the everyday practice of companies will contribute to increased energy security and the protection of the planet’s resources. Full article

The increasing global demand for renewable energy has resulted in a high interest in wind power, with offshore wind farms offering better performance than onshore installations. Coastal nations are thus, actively developing offshore wind turbines, where monopiles are the predominant foundation type. Despite their widespread use, the effects of monopile installation methods on the overall foundation behaviour are not sufficiently yet understood. This study investigates how different pile installation procedures—jacked and impact-driven—affect the lateral capacity of monopile foundations under both monotonic and dynamic lateral loads, by comparing them with wished-in-place monopiles, the usual assumption in design, for which no soil disturbance due to installation is considered. Three finite element 3D models were employed to simulate these cases, i.e., wished-in-place monopile, jacked, and impact-driven pile, incorporating soil zoning in the latter cases to replicate the effects of the installation methods. Comparisons between all these models, when subject to lateral monotonic and cyclic loads, are presented and discussed in terms of displacements in the soil and horizontal normal stresses. Results reveal that these installation methods significantly influence soil reactions, impacting the lateral performance of monopiles under both monotonic and dynamic conditions. The impact-driven pile demonstrated the most significant influence on the monopile behaviour. These findings highlight the need for engineers to account for installation effects in the design of monopile foundations to enhance performance and reliability, as well as the optimisation of their design. Full article

The Betz constant is the well-known aerodynamic limit of the maximum power which can be extracted from wind using wind turbine technologies, under the assumption that the wind speed is uniform across a blade disk. However, this condition may not hold for large wind turbines, since the wind speed may not be constant along their height; rather, it may vary with the location due to surface friction from tall buildings and trees, the topography of the Earth’s surface, and radiative heating and cooling in a 24 h cycle. This paper derives a new power coefficient for large wind turbines based on the power law exponent model of the wind gradient and height. The proposed power coefficient is a function of the size of the rotor disk and the Hellmann exponent, which describes the wind gradient based on wind stability at various locations, and it approaches the same value as the Betz limit for wind turbines with small rotor disks. It is shown that for large offshore wind turbines, the power coefficient was about 1.27% smaller than that predicted by the Betz limit, whereas for onshore turbines in human-inhabited areas with stable air, the power coefficient was about 8.7% larger. Our results are significant in two ways. First, we achieve generalization of the well-known Betz limit through elimination of the assumption of a constant wind speed across the blade disk, which does not hold for large wind turbines. Second, since the power coefficient depends on the location and air stability, this study offers guidelines for wind power companies regarding site selection for the installation of new wind turbines, potentially achieving greater energy efficiency than that predicted by the Betz limit. Full article

With the increasing proportion of renewable energy in power grids, the inertia level and frequency regulation capability of modern power systems have declined. In response, this paper proposes a coordinated frequency regulation strategy integrating power generation, energy storage, and DC transmission for offshore wind power MMC-HVDC transmission systems, aimed at improving the frequency stability of onshore power grids. First, considering the inability of the receiving-end MMC-HVDC converter station under constant DC voltage control to directly respond to AC system frequency variations, a frequency regulation method is developed based on constant DC voltage control. The approach employs DC voltage as a transmission signal to coordinate the responses of wind turbines and energy storage systems. Subsequently, based on the energy storage configuration of the onshore renewable energy aggregation station, a secondary frequency regulation strategy is proposed. This strategy integrates offshore wind power, MMC-HVDC transmission system, and energy storage systems, balancing AC frequency regulation and the recovery of the state of charge (SOC) of the energy storage system. Finally, the proposed method is tested on a modified IEEE 39-bus system, the results demonstrate that the minimum frequency value can be in-creased by 37.5%, the system frequency can be restored to the initial state after secondary FM, and the results demonstrate its effectiveness. Full article

Optimizing offshore wind power technology and reducing the levelized cost of electricity throughout the lifecycle are key measures for the large-scale development of offshore wind power, contributing significantly to the transition toward sustainable energy systems. However, compared to onshore wind power, the internal flow dynamics of offshore wind farms are more complex, which poses challenges for operation and maintenance. Therefore, there is an urgent need for updated, smarter, more efficient, and economic offshore intelligent operation control technologies to facilitate the large-scale development and utilization of offshore wind power. This paper approaches the topic from two perspectives, offshore wind turbines and offshore wind farms, introducing popular research directions and technical bottlenecks in these two related fields. This includes offshore wind turbine capacity development and fundamental technologies, offshore wind power forecasting technology, and offshore wind power operation and control technology, offshore intelligent operation and maintenance technology, as well as offshore wind power and integrated marine area utilization technology. Firstly, the challenges faced by the intensive development of offshore wind resources and operational environments are analyzed. Secondly, the challenges encountered in the aforementioned technological areas and their potential solutions are summarized. Finally, a systematic reflection and outlook on the large-scale development of offshore wind power are provided, reinforcing its critical role in achieving global sustainability goals. Full article

The cost of a wind turbine support structure is high and this support structure is difficult to repair, especially for offshore wind turbines. As such, the loads and stresses that occur during the actual operation of wind turbines must be monitored from the perspective of maintenance planning and lifetime prediction. Strain measurement methods are generally used to monitor the load on a structure and are highly accurate, but their widespread implementation across all wind turbines is impractical due to cost and labor constraints. In this study, a method for predicting the tower load was developed, using simple measurements applied during power generation, for onshore wind turbines. The method consists of a machine learning model, using the nacelle displacement and nacelle angle as inputs, which are highly correlated with loads at the bottom of the tower. Nacelle displacements can be derived from accelerations, which are already monitored in regard to most wind turbines; the nacelle angle can be calculated from the nacelle angle velocity, measured with a gyroscope. The low-frequency components that cannot be captured with these parameters were predicted using the operational condition data used for wind turbine control. Additionally, the prediction accuracy was increased by creating and integrating separate machine learning models for each typical vibration component. The method was evaluated through the aeroelastic simulation of a 2 MW wind turbine. The results showed that the fatigue and extreme loads of the fore–aft and side–side bending moments at the bottom of the tower can be predicted using operational conditions and nacelle accelerations, and the prediction accuracy in regard to the high-frequency components can be increased by adding the nacelle angle velocity into the model. Furthermore, the fatigue loads of the torsional torque can be evaluated using the nacelle angle velocity. The proposed method has the ability to predict the loads at the bottom of the tower without any, or with only a few, additional sensors. Full article

In recent decades, wind turbine installations have become a popular option to meet the world’s growing demand for energy. Both onshore and offshore wind turbines form pivotal components of the electricity sector. Onshore wind energy is now a mature technology, with significant experience gained by wind farm developers and operators over the last couple of decades. However, as a more recent enterprise, the offshore wind industry still requires significantly more development before the technologies and operations reach maturity. To date, floating platforms at sea have been utilised extensively for the oil and gas industry. While a lot of the expertise and technology is transferable to the floating offshore wind industry, significant development work remains; for example, there is significant work required due to the different device types. Compared to floating oil and gas platforms, floating wind turbine platforms have a higher centre of gravity, which influences their performance and complexity. The successful large-scale development of floating offshore wind farms will require significant expertise and learning from the onshore wind, oil, and gas sectors. There are a wide range of software packages available to predict the operational behaviour of floating offshore wind turbines. In spite of this, it is still extremely difficult to create a fully coupled model of a floating wind turbine that can accurately and comprehensively model the turbine aerodynamics, hydrodynamics, servodynamics, structural dynamics, and mooring dynamics. This paper presents details on various fully coupled and uncoupled software packages and methodologies utilised to simulate floating offshore wind turbine performances. Various kinds of mooring systems, floating wind turbines, analysis methods, and experimental validation methods are comprehensively described. This paper serves as a reliable methodological guideline for researchers and wind industry professionals engaged in the design/analysis of wind farm projects. Full article