Turbine Locations Research Articles

Prospects for use of man-made disturbed lands in mining regions for the location of renewable energy sources facilities

This article describes the prospects for use of man-made disturbed lands of mining regions, which for a number of reasons are not subject to recultivation, in the context of the effective use of renewable energy sources. The use of renewable energy sources is considered, first of all, to satisfy energy needs, but taking into account their environmental value and renewability. It is shown the importance of decentralization of power supply sources for consumers, which can be achieved through the use of renewable energy sources. The article provides a brief structure of Ukraine's energy consumption. The main obstacles that stand in the way of the development of renewable energy sources and improvement of energy efficiency in Ukraine are analyzed. As one of the perspective directions for the introduction of renewable energy sources, the use of wind power plants is considered. The main advantages of wind energy are listed. Formulas for calculating the power of a wind power plant are provided. The gross potential, technical potential and economic potential of the implementation of wind power plants are considered. The coefficient of wind energy utilization, which depends on the wind speed, is given. The paper gives a comparative assessment of existing types of wind turbines – with a horizontal and a vertical axis of rotation. It has been proved that vertical axis wind power plans are more effective for implementation. The vertical axis wind power plans have their advantages. It is recommended to use vertical axis wind power plans with using of a magnetic levitation. This makes vertical axis wind turbines the most efficient. Due to the use of wind generators with a vertical axis of rotation of a turbine with a magnetic-levitating bearing, in the conditions of Kryvbas, vertical wind power plants can produce electricity more than 7 times more than traditional (horizontal) ones. It has been proven that the amount of generated electricity increases with the height of the wind turbine location. The article examines the ecological advantages of placing wind power plans on man-made disturbed lands of mining regions.

Study on Distributed Power-Collection and Cascaded Boosting-Voltage Topology and Strategy for Offshore DC Station

Different from traditional concentrated power-collection and boosting-voltage (CPCB) topology adopted by HVDC station, this paper adopts a distributed power-collection and cascaded boosting-voltage (DPCB) topology for offshore DC station to collect DC power and boost DC voltage, which consists of multiple cascaded single active bridges (SABs). It has merits of strong DC-voltage boosting ability, low design difficulty and cost, and low system error rate. Three aspects are studied as follows. First, DPCB topology with its circuit equations is deduced step by step, and its operational mechanism is analysed under phase-shifting control method further. Second, PI control strategy is designed based on system small signal model, and system performance is analyzed by Bode diagram. Third, fault tolerance strategy with predicted power ratio is designed to keep DPCB station from breakdown when some SABs and generators are out of order, and enormous power difference occurs due to the factors of wind turbine location and windward. Finally, the feasibility and effectiveness of designed DPCB station with its strategy are verified by experiment results.

Discrete complex-valued code pathfinder algorithm for wind farm layout optimization problem

• A discrete complex-valued code pathfinder algorithm (DCPFA) has been proposed. • The DCPFA algorithm’s exploration and exploitation abilities were improved. • The DCPFA is applied to solve wind farm layout optimization (WFLO) problem. • The experimental results show that DCPFA found solutions have lower cost values per unit of power. In wind farm planning, it is necessary to optimize the location of turbines to reduce the influence of eddy currents between each other and generate more energy. This problem is also transformed into a discrete optimization problem, it is named wind farm layout optimization (WFLO) problem, to solve this optimization problem we can obtain the optimal turbine placement scheme. With the complexity of wind condition in WFLO problem increases, it becomes very difficult to solve, so more and more researchers use metaheuristic algorithms to solve this problem. Improve the solution accuracy of the WFLO problem, it will increase renewable energy use and lowering carbon emissions. In order to improve the solution accuracy of WFLO problem, a discrete complex-valued code pathfinder algorithm (DCPFA) has been proposed in this paper, and used to solve the WFLO problem. In DCPFA, the algorithm’s exploration ability was improved, and the algorithm achieves a balance between exploration and exploitation. To test the performance of DCPFA in solving the WFLO problem, two complex wind conditions in wind farms are simulated. Comparing the results with other famous metaheuristic optimization algorithms and recently published literature, the DCPFA found a solution that will have lower cost values per unit of power, such as DCPFA’s solution in wind condition (1) can output 34120(KW), it is bigger than RSA’s 32498(KW) and GA’s 32038(KW), DCPFA’s solution in wind condition (2) can output 19375(KW), it is bigger than SSA’s 17781(KW) and BPSO-TVAV’s 15796 (KW). More importantly, in the objective function (Cost/KW), DCPFA is also ranked first in two wind condition. According to the experimental results, it can be explained that DCPFA’s effectiveness and robustness in solving WFLO problems.

Ensemble-Based Flow Field Estimation Using the Dynamic Wind Farm Model FLORIDyn

Wind farm control methods allow for a more flexible use of wind power plants over the baseline operation. They can be used to increase the power generated, to track a reference power signal or to reduce structural loads on a farm-wide level. Model-based control strategies have the advantage that prior knowledge can be included, for instance by simulating the current flow field state into the near future to take adequate control actions. This state needs to describe the real system as accurately as possible. This paper discusses what state estimation methods are suitable for wind farm flow field estimation and how they can be applied to the dynamic engineering model FLORIDyn. In particular, we derive an Ensemble Kalman Filter framework which can identify heterogeneous and changing wind speeds and wind directions across a wind farm. It does so based on the power generated by the turbines and wind direction measurements at the turbine locations. Next to the states, this framework quantifies uncertainty for the resulting state estimates. We also highlight challenges that arise when ensemble methods are applied to particle-based flow field simulations. The development of a flow field estimation framework for dynamic low-fidelity wind farm models is an essential step toward real-time dynamic model-based closed-loop wind farm control.

Multi-Scale Numerical Assessments of Urban Wind Resource Using Coupled WRF-BEP and RANS Simulation: A Case Study

Urban wind resource assessments (WRAs) contribute to the effective exploitation of wind energy and thus are of significant importance to the sustainable development of cities. To improve the simulation accuracy of urban wind flow with high spatial resolution, this study implemented a multi-scale numerical assessment of the wind power potential in a highly-urbanized region with realistic terrain conditions by integrating the Reynolds-averaged Navier-Stokes (RANS) equations into the Weather Research and Forecasting (WRF) model with Building Effect Parameterization (WRF-BEP). The sensitivity analyses are first conducted to obtain an appropriate combination of physical parameterization schemes in the WRF-BEP model. Then, the wind tunnel tests are performed to validate the computational accuracy of urban wind flow using the RANS equations. Based on a close examination of the urban wind flow resulting from the coupled WRF-BEP and RANS simulations, the integration of micro-wind turbines into the building skin is not recommended in the highly-urbanized region. Furthermore, five optimum roof installation locations with low turbulence intensities (smaller than 18%) and high wind power densities (approximately 220 W/m2, 260 W/m2, 270 W/m2, 300 W/m2 and 400 W/m2, respectively) are identified. Finally, the important effects of the terrain conditions, planetary boundary layer (PBL) parameterization schemes and turbulence models on WRAs are discussed. The results of WRAs in this multi-scale numerical case study presented a systemic approach to effectively determine the installation locations of micro-wind turbines that possess the greatest potential to harness wind energy in a realistic highly-urbanized area.

Thermofluid effects of solar chimney geometry on performance parameters

The solar chimney system (SCS) is a novel application that has recently become the focus of researchers in this field. The current study included a numerical simulation of changing all the variables defining the system's shape construction, in addition to the influence of curvatures on performance assessment. The approach confirms the SCS output power, velocity, and temperature based on studying more than 40 cases in various assemblages. These sets are grouped into diverse forms by changing variable parameters, including collector angle, chimney angle, collector height, turbine location, fillet radius, and shape. The findings indicated that increasing the chimney angle up to 3° increases both velocity and efficiency, while the increment in maximum velocity reaches 200% which radically improves the system power output. The change of the chimney inlet height influences the average velocity substantially from 2.04 to 2.41. The effect of collector angle efficiently improves the SCS performance for the positive angles, where the maximum increment in average velocity equals 6.25%. The greater the collector height up to 70% of turbine radius, the increase in the mass flow. The concaved shape of chimney reduces flow separation and the energy loss resulting from eddies inside it.

Determination of the Response Amplitude Operator of a tidal turbine as a spectral transfer function

A transfer function determination method is proposed in this study to predict the unsteady fluctuations of the performance of a tidal turbine model. This method is derived from the Response Amplitude Operator (RAO) applied in the offshore industry to predict linear wave-induced loads on large structures. It is based on a spectral approach and requires the acquisition of a turbine parameter (e.g. torque, thrust, power or root-blade force) in synchronization with an upstream flow velocity measurement. On the frequency range where the causality between these two signals is proven, the transfer function is established using the ratio between the cross-spectral density and the spectral density of the incoming velocity.The linearity is verified using the coherence function, which shows validity for the turbine power in the lowest frequencies only. This transfer function is then used to reconstruct the power fluctuations which is compared to the recorded one for a particular flow condition with bathymetry generated turbulence. The result shows the dependence on the accurate location of the velocity measurement point used for the reconstruction. This point must exactly correspond to the expected turbine location, i.e. where the turbine response needs to be processed. Bearing in mind its limits, the method can be used to predict the loadings of extreme events on the turbine structure and the performance variations corresponding to the unsteady characteristics of a turbulent flow, for a better grid integration.

Evaluation of Technical Solutions to Improve Transient Stability in Power Systems with Wind Power Generation

Reliability and safety must be carefully considered in today’s power systems, which are rapidly evolving toward ever higher penetration of renewable, inverter-based generation units. Power systems are constantly stressed by active power disturbances, which can be exacerbated by wind and solar systems that are subject to rapid fluctuations in primary energy. In this framework, a comparative technical analysis of solutions to improve transient stability, both rotor angle stability and frequency stability, is carried out. These solutions can be adopted by the transmission system operator (e.g., an additional parallel transmission line), by the generation companies (e.g., a fast excitation system), or by both, such as SVC (static VAR compensator) and STATCOM (static synchronous compensator). Sensitivity analyses were carried out to assess the impact of the location of the wind turbines in the buses of the grid on their rated power and level of production. On the basis of these analyses, the worst-case fault was considered, and the critical fault recovery time was determined as an engineering parameter to compare the different solutions. For the numerical analysis, a modified IEEE 9-bus system was considered, and the PowerWorld software tool was used. Rotor angle and frequency stability analyses were performed.

Wind turbine wakes can impact down-wind vegetation greenness

Global wind energy has expanded 5-fold since 2010 and is predicted to expand another 8–10-fold over the next 30 years. Wakes generated by wind turbines can alter downwind microclimates and potentially downwind vegetation. However, the design of past studies has made it difficult to isolate the impact of wake effects on vegetation from land cover change. We used hourly wind data to model wake and non-wake zones around 17 wind facilities across the U.S. and compared remotely-sensed vegetation greenness in wake and non-wake zones before and after construction. We located sampling sites only in the dominant vegetation type and in areas that were not disturbed before or after construction. We found evidence for wake effects on vegetation greenness at 10 of 17 facilities for portions of, or the entire growing season. Evidence included statistical significance in Before After Control Impact statistical models, differences >3% between expected and observed values of vegetation greenness, and consistent spatial patterns of anomalies in vegetation greenness relative to turbine locations and wind direction. Wakes induced both increases and decreases in vegetation greenness, which may be difficult to predict prior to construction. The magnitude of wake effects depended primarily on precipitation and to a lesser degree aridity. Wake effects did not show trends over time following construction, suggesting the changes impact vegetation greenness within a growing season, but do not accrue over years. Even small changes in vegetation greenness, similar to those found in this study, have been seen to affect higher trophic levels. Given the rapid global growth of wind energy, and the importance of vegetation condition for agriculture, grazing, wildlife, and carbon storage, understanding how wakes from wind turbines impact vegetation is essential to exploit or ameliorate these effects.

The potential of wind energy in Kuwait: a complete feasibility investigation

Energy prospectors are seeking to diversify the energy resources, reduce air pollution, and protect the economy from unstable crude oil prices. In this regard, the wind energy is an attractive source of renewable energy. In this paper, the potential of wind energy generated in wind farms is statically predicated and assessed. The average speed from four weather stations in Kuwait from 2009 to 2017 is adopted in the investigation, and three of these stations are onshore and one offshore. The value of the dimensionless Weibull shape and scale parameters are calculated. The maximum yearly value for Weibull shape parameter is 4.76, and the maximum yearly value for scale parameter is 8.35 m/s. The highest recorded monthly wind power density is 257.36 W/m2. The analyses indicated that the maximum yearly output energy of 11.71 GW-h can be produced by a 3.0 MW wind turbine. According to the European Wind Energy Association (EWEA) classification, the Alsalmi, the Airport, and the Failaka island are not a favorable location for wind turbine location, while the Miribah is fairly good.

An adaptive replacement strategy-incorporated particle swarm optimizer for wind farm layout optimization

The wind farm layout optimization (WFLO) aims to maximize power generation of a wind farm by optimizing the location of wind turbines. Traditional mathematical methods cannot provide a satisfactory solution for a wind farm due to the high complexity of the problem. Meta-heuristic algorithms have been used to optimize it. Particularly, genetic algorithms (GA) have been widely used and obtained success in WFLO problems. However, GA still suffers from the issues of insufficient optimization efficiency. In this study, a genetic learning particle swarm optimization with an adaptive strategy, termed AGPSO, is proposed to optimize WFLO problems. The strategy adaptively adjusts the location of the worst turbine to improve the conversion efficiency of a wind farm. Four wind scenarios, including single wind speed with single wind direction, single wind speed with uniform multiple wind directions, single wind speed with nonuniform multiple directions, and multiple wind speeds with multiple wind directions scenarios ones, are utilized to verify the effectiveness of AGPSO and the effect of different wind scenarios for it. Twelve constraints and three different scales are used to further verify the robustness of AGPSO and the effect of wind turbine location on WFLO problems. Extensive numerical experiment results demonstrate that AGPSO performs significantly better than other twelve state-of-the-art competitors in terms of conversion efficiency under different wind farms, wind scenarios, and constraints. AGPSO obtains the best average of 89.92%, 92.90%, 95.39%, and 90.75% conversion efficiency in a wind farm with 25 wind turbines under four wind scenarios, respectively.

Historical wind deployment and implications for energy system models

A critical parameter in modeling studies of future decarbonized energy systems is the potential future capacity for onshore wind power. Wind power potential in energy system models is subject to assumptions regarding: (i) constraints on land availability for wind deployment; (ii) how densely wind turbines may be placed over larger areas, and (iii) allocation of capacity with respect to wind speed. By analyzing comprehensive databases of wind turbine locations and other GIS data in eleven countries and seventeen states in Australia, Canada, and the US; all with high penetration levels of wind power, we find that: i) large wind turbines are installed on most land types, even protected areas and land areas with high population density; ii) it is not uncommon with a deployment density up to 0.5 MW/km2 on municipality or county level, with rare outlier municipalities reaching up to 1.5 MW/km2 installed capacity; and iii) wind power has historically been allocated to relatively windy sites with average wind speed above 6 m/s. In many cases, allocation methods used in energy system models do not consistently reflect actual installations. For instance, we find no evidence of concentration of installations at the windiest sites, as is frequently assumed in energy system models. We conclude that assumptions made in models regarding wind power potentials are poorly reflective of historical installation patterns, and we provide new data to enable assumptions that have a more robust empirical foundation.

Cooling Techniques in Direct-Drive Generators for Wind Power Application

Direct-drive generators are an attractive candidate for wind power application since they do not need a gearbox, thus increasing operational reliability and reducing power losses. However, this is achieved at the cost of an increased generator size, larger inverter and decreased thermal performance. The associated cooling system is therefore crucial to keep the generator and inverter sizes down and to operate within the safe thermal limits. Various cooling techniques suitable for generators are therefore reviewed and analyzed in this paper. The performance and maintenance requirements are unavoidable compromises that need to be investigated together, especially for large generators. The location of the wind turbine is also important and dictates critical issues such as accessibility and maximum size. The key novelty in this paper is the assessment of the cooling methods based on generator size, reliability and maintenance requirements.

Offshore Wind Farm Layout Optimization Considering the Power Collection System Cost

The paper proposes a method for optimizing the layout of offshore wind farms to increase their efficiency by reducing the effect of aerodynamic shading, minimizing electrical losses in cable lines of the system for receiving and transmitting electrical energy generated by wind turbines to the electrical grid of the power system. The task is reduced to determining several parameters that define the geometric dimensions and shape of the layout grid with pre-installed tur-bine locations. This approach, in contrast to the coordinate-wise search method, makes it possible to build symmetrical grid layouts of wind power plants, which in practice are more convenient in terms of maintenance and operation. Together with the optimization of the layout, the search for the optimal location of the offshore transformer substation and the synthesis of the scheme of cable joints between wind power plants has been carried out. To solve this problem, a heuristic algorithm was used to search for a minimum spanning tree with a restriction on the conductivity of connections, which made it possible to build realistic schemes and more adequately assess their technical and economic characteristics. As the results of testing the proposed methodology on the example of optimizing the layout of the Horns Rev 1 wind farm have shown, the use of this approach has reduced the cost of the electrical system by 10–12 %. This is 7–11 % higher than the result obtained by using the MST algorithm, which performs the construction of a circuit of cable joints of a simplified topology. The change in the size and shape of the boundaries of the wind farm site resulted in an increase in the estimated electricity generation by 2.3 % and a decrease in its cost by 4 %. When optimizing the layout of wind turbines within the fixed boundaries of the site, these indicators are improved by only 1 and 2 % as compared to the original scheme.

Integrated Layout and Cable Routing in Wind Farm Optimal Design

We address a very important problem in offshore wind farm design, namely, the combined optimization of the turbine location and of the connection cables required to bring the electrical power produced by the turbines to a given substation, and eventually to shore. We first describe a mixed-integer linear programming model that combines previous proposals from the literature. Then we improve it by a number of additional inequalities intended to strengthen its linear programming relaxation. In particular, we propose new classes of Benders-like cuts derived from an induced-clique substructure of the problem. The validity of these cuts is established in a purely combinatorial way, without resorting to Benders’s standard duality theory, and efficient separation procedures are proposed. The practical effectiveness of the proposed cuts is established through computational tests, showing that they do improve very significantly the dual bound provided by the standard model. We also present an exact branch-and-cut solver for the problem, which separates the new cuts at run time. Computational results confirm that the new cuts are instrumental for the success of our exact solver. This paper was accepted by Chung-Piaw Teo, optimization. Funding: This work of Matteo Fischetti was supported by the Ministero dell’Istruzione, dell’Università e della Ricerca (MiUR), Italy [PRIN Project]. Supplemental Material: Data are available at https://doi.org/10.1287/mnsc.2022.4470 .

Energy Efficiency of Small Wind Turbines in an Urbanized Area—Case Studies

This study aimed to determine whether the wind zone that characterizes a given area of the country in open area is reflected in the built-up area lying within the zone. Analysis included four Polish cities located in different wind zones. The two-parameter Weibull density distribution function was used to present the wind conditions at each location. Two 3 kW VAWT devices were selected to evaluate the productivity of wind turbines at the locations analyzed. It was shown that the wind zones characterizing the wind potential of a region in an open area have no significant influence on the wind conditions in the built-up area located in that area. It was determined that the study location’s did not exhibit wind potential that could be economically justified by a wind turbine. WTs in the city do not reach their nominal productivity. A decisive advantage of very light winds was observed (up to 2 m/s) and a large proportion of so-called atmospheric calms. It was shown that the installation of small wind turbines in an urbanized area requires a minimum of annual wind measurements at the exact location and height of each future turbine planned.

Exploring the trilemma of cost-efficiency, landscape impact and regional equality in onshore wind expansion planning

Onshore wind development has historically focused on cost-efficiency, which may lead to uneven turbine distributions and public resistance due to landscape impacts. Using a multi-criteria planning approach, we show how onshore wind capacity targets can be achieved by 2050 in a cost-efficient, visually unobtrusive and evenly distributed way. For the case study of Germany, we build on the existing turbine stock and use open data on technically feasible turbine locations and data on scenicness of landscapes to plan the optimal expansion. The analysis shows that while the trade-off between optimizing either cost-efficiency or landscape impact of the turbines is rather weak with about 15% higher costs or scenicness, an even distribution has a large impact on these criteria. However, a more evenly distributed expansion is necessary for the achievement of the targeted south quota, a policy target that calls for more wind turbine additions in southern Germany. Our analysis assists stakeholders in resolving the onshore wind expansion trilemma.

A techno-economic model for avoiding conflicts of interest between owners of offshore wind farms and maintenance suppliers

Currently, wind energy is one of the most important sources of renewable energy. Offshore locations for wind turbines are increasingly exploited because of their numerous advantages. However, offshore wind farms require high investment in maintenance service. Due to its complexity and special requirements, maintenance service is usually outsourced by wind farm owners. In this paper, we propose a novel approach to determine, quantify, and reduce the possible conflicts of interest between owners and maintenance suppliers. We created a complete techno-economic model to address this problem from an impartial point of view. An iterative process was developed to obtain statistical results that can help stakeholders negotiate the terms of the contract, in which the availability of the wind farm is the reference parameter by which to determine penalisations and incentives. Moreover, a multi-objective programming problem was addressed that maximises the profits of both parties without losing the alignment of their interests. The main scientific contribution of this paper is the maintenance analysis of offshore wind farms from two perspectives: that of the owner and the maintenance supplier. This analysis evaluates the conflicts of interest of both parties. In addition, we demonstrate that proper adjustment of some parameters, such as penalisation, incentives, and resources, and adequate control of availability can help reduce this conflict of interests.

A Meandering-Capturing Wake Model Coupled to Rotor-Based Flow-Sensing for Operational Wind Farm Flow Prediction

The development of new wake models is currently one of the key approaches envisioned to further improve the levelized cost of energy of wind power. While the wind energy literature abounds with operational wake models capable of predicting in fast-time the behavior of a wind turbine wake based on the measurements available (e.g., SCADA), only few account for dynamic wake effects. The present work capitalizes on the success gathered by the Dynamic Wake Meandering formulation and introduces a new operational dynamic wake modeling framework aimed at capturing the wake dynamic signature at a low computational cost while relying only on information gathered at the wind turbine location. In order to do so, the framework brings together flow sensing and Lagrangian flow modeling into a unified framework. The features of the inflow are first inferred from the turbine loads and operating settings: a Kalman filter coupled to a Blade Element Momentum theory solver is used to determine the rotor-normal flow velocity while a Multi-Layer Perceptron trained on high-fidelity numerical data estimates of the transverse wind velocity component. The information recovered is in turn fed to a Lagrangian flow model as a source condition and is propagated in a physics-informed fashion across the domain. The ensuing framework is presented and then deployed within a numerical wind farm where its performances are assessed. The computational affordability of the proposed model is first confirmed: 7 × 10−4 wall-clock seconds per simulation second are required to simulate a small 12 turbines wind farm. Large Eddy Simulations of wind farm using advanced actuator disks are then used as a baseline and a strong focus is laid on the study of the wake meandering features. Comparison against the Large Eddy Simulation baseline reveals that the proposed model achieves good estimates of the flow state in both low and high Turbulence Intensity configurations. The model distinctly provides additional insight into the wake physics when compared to the traditional steady state approach: the wake recovery is consistently accounted for and the wake meandering signature is captured as far as 12D downstream with a correlation score ranging from 0.50 to 0.85.

Land Subsidence Assessment for Wind Turbine Location in the South-Western Part of Madagascar

Finding a suitable location is a key factor for long-term investment in wind turbine energy. It includes understanding the area of interest, such as the subsidence of the land. Land subsidence is a gradual decrease in the surface of the Earth due to natural and/or induced causes. It can cause damage, such as settlement problems in the ground near infrastructure including buildings and wind turbines, thus not being a suitable place for long-term investment. Here, we show a case study of land subsidence prediction and assessment of the Atsimo Andrefana region, the great south-western part of Madagascar, using theoretical simulation and satellite images from the Sentinel-1 mission using D-InSAR method. The predicted land subsidence related to the depletion of groundwater reservoirs in the Atsimo Andrefana region is around 12 mm. We found ~5 mm of subsidence related to the growing city of Toliary and with an average subsidence of 124 mm and the highest record of 167 mm in the most southern part of the region for a period of 6 months. The spatial distribution of land subsidence allows us to choose the ideal location for wind turbine settlement, where land subsidence is not that severe, i.e., the areas with subsidence relatively low of equal or less than 10 mm within 6 months of observation, based on the processed data. Such results are essential for future environmentally friendly investments in the affected region, as the demand for green energy will always grow.