Activity Pattern and Correlation between Bat and Insect Abundance at Wind Turbines in South Sweden

We present data on species composition and activity of bats during two years at three different wind- turbines, located in south Sweden, both at the base and nacelle height. To test the hypothesis that bats are attracted to wind turbines because of feeding opportunities, insects were sampled at nacelle height at one wind turbine using a suction trap, simultaneously as bat activity were measured. At this wind turbine, we also compared two different technical systems for ultrasound recordings and collect meteorological data. The variation in bat activity was high between nights and between wind turbines. In addition to the expected open-air foraging species (Pipistrellus, Nyctalus, Vespertilio and Eptesicus), some individuals of unexpected species (Myotis, Barbastella, and Plecotus) were found at nacelle height. There was a weak but significant positive relation between bat activity and insect abundance, so the hypothesis could not be rejected, suggesting there might be other factors than insect abundance explaining the frequency of bat visits at the nacelle. We found a strong correlation between bat passes and weather conditions. A reasonable way to mitigate collisions is with stop-regulation. However, this study highlights some of the problems with defining the limits for stop-regulation based on weather conditions.

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Rain Erosion Maps for Wind Turbines Based on Geographical Locations: A Case Study in Ireland and Britain

Journal of Bio- and Tribo-Corrosion ◽

10.1007/s40735-021-00472-0 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

K. Pugh ◽

M. M. Stack

Keyword(s):

Wind Turbine ◽

Western Europe ◽

Meteorological Data ◽

Turbine Blades ◽

Weather Conditions ◽

Annual Rainfall ◽

Wind Turbine Blades ◽

Weather Patterns ◽

The Uk

AbstractErosion rates of wind turbine blades are not constant, and they depend on many external factors including meteorological differences relating to global weather patterns. In order to track the degradation of the turbine blades, it is important to analyse the distribution and change in weather conditions across the country. This case study addresses rainfall in Western Europe using the UK and Ireland data to create a relationship between the erosion rate of wind turbine blades and rainfall for both countries. In order to match the appropriate erosion data to the meteorological data, 2 months of the annual rainfall were chosen, and the differences were analysed. The month of highest rain, January and month of least rain, May were selected for the study. The two variables were then combined with other data including hailstorm events and locations of wind turbine farms to create a general overview of erosion with relation to wind turbine blades.

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Analysis of the Patent of a Protective Cover for Vertical-Axis Wind Turbines (VAWTs): Simulations of Wind Flow

Sustainability ◽

10.3390/su12187818 ◽

2020 ◽

Vol 12 (18) ◽

pp. 7818

Author(s):

Jose Alberto Moleón Baca ◽

Antonio Jesús Expósito González ◽

Candido Gutiérrez Montes

Keyword(s):

Wind Speed ◽

Wind Turbine ◽

Wind Turbines ◽

High Speed ◽

Experimental Tests ◽

Weather Conditions ◽

Vertical Axis ◽

Good Alternative ◽

Wind Speeds ◽

Vertical Axis Wind Turbines

This paper presents a numerical and experimental analysis of the patent of a device to be used in vertical-axis wind turbines (VAWTs) under extreme wind conditions. The device consists of two hemispheres interconnected by a set of conveniently implemented variable section ducts through which the wind circulates to the blades. Furthermore, the design of the cross-section of the ducts allows the control of the wind speed inside the device. These ducts are intended to work as diffusers or nozzles, depending on the needs of the installation site. Simulations were performed for the case of high-speed external wind, for which the ducts act as diffusers to reduce wind speed and maintain a well-functioning internal turbine. Four different patent designs were analyzed, focusing on turbine performance and generated power. The results indicate that the patent allows the generation of electric power for a greater range of wind speeds than with a normal wind turbine. The results support that this patent may be a good alternative for wind power generation in geographic areas with extreme weather conditions or with maintained or strong gusty wind. Experimental tests were carried out on the movement of the blades using the available model. Finally, the power curve of the model of this wind turbine was obtained.

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Modelling Types 1 and 2 Wind Turbines Based on IEC 61400-27-1: Transient Response under Voltage Dips

Energies ◽

10.3390/en13164078 ◽

2020 ◽

Vol 13 (16) ◽

pp. 4078 ◽

Cited By ~ 1

Author(s):

Tania García-Sánchez ◽

Irene Muñoz-Benavente ◽

Emilio Gómez-Lázaro ◽

Ana Fernández-Guillamón

Keyword(s):

Wind Turbine ◽

Wind Power ◽

Wind Turbines ◽

Distribution System ◽

Power Plants ◽

Short Circuit ◽

Energy Resource ◽

Weather Conditions ◽

International Electrotechnical Commission ◽

Voltage Dips

Wind power plants depend greatly on weather conditions, thus being considered intermittent, uncertain and non-dispatchable. Due to the massive integration of this energy resource in the recent decades, it is important that transmission and distribution system operators are able to model their electrical behaviour in terms of steady-state power flow, transient dynamic stability, and short-circuit currents. Consequently, in 2015, the International Electrotechnical Commission published Standard IEC 61400-27-1, which includes generic models for wind power generation in order to estimate the electrical characteristics of wind turbines at the connection point. This paper presents, describes and details the models for wind turbine topologies Types 1 and 2 following IEC 61400-27-1 for electrical simulation purposes, including the values for the parameters for the different subsystems. A hardware-in-the-loop combined with a real-time simulator is also used to analyse the response of such wind turbine topologies under voltage dips. The evolution of active and reactive powers is discussed, together with the wind turbine rotor and generator rotational speeds.

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Potential of Shrouded Micro Wind Turbine

IRA-International Journal of Technology & Engineering (ISSN 2455-4480) ◽

10.21013/jte.icsesd201732 ◽

2017 ◽

Vol 7 (2 (S)) ◽

pp. 340

Author(s):

Kishor Sontakke ◽

Samir Deshmukh ◽

Sandip Patil

Keyword(s):

Renewable Energy ◽

Wind Turbine ◽

Wind Turbines ◽

Renewable Energy Sources ◽

Turbine Blades ◽

Weather Conditions ◽

Power Coefficient ◽

Solar Panels ◽

Wind Speeds ◽

Low Wind Speeds

The growing demand for electrical energy for industrial and domestic use, coupled with the limited amount of available fossil fuel reserves and its negative effects on the environment, have made it necessary to seek alternative and renewable energy sources. The use of renewable energy is promoted worldwide to be less dependent on conventional fuels and nuclear energy. Therefore research in the field is motivated to increase efficiency of renewable energy systems. This study aimed to study potential of micro wind turbine and velocity profile through shroud for low wind speeds. Although there is a greater inclination to use solar panels because of the local weather conditions, there are some practical implications that have place the use of solar panels in certain areas to an end. The biggest problem is panel stealing. Also, in some parts of the country the weather is more appropriate to apply wind turbines. Thus, this study paying attention on the design of a new concept to improve wind turbines to be appropriate for the low wind speeds in India. The concept involves the implementation of a concentrator and diffuser to a wind turbine, to increase the power coefficient. Although the wind turbine was not tested for starting speeds, the realization of the shroud should contribute to improved starting of the wind turbine at lower wind speeds. The configuration were not manufactured, but simulated with the use of a program to obtain the power production of the wind turbine over a range of wind speeds. These values were compared to measured results of an open wind turbine developed. The most important topic at hand when dealing with a shrouded wind turbine is to find out if the overall diameter or the blade diameter of the turbine should be the point of reference. As the wind turbine is situated in a shroud that has a larger diameter than the turbine blades, some researchers believe that the overall diameter should be used to calculate the efficiency. The benefits of shrouded wind turbines are discussed.

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Failure Modes, Effects and Criticality Analysis for Wind Turbines Considering Climatic Regions and Comparing Geared and Direct Drive Wind Turbines

10.20944/preprints201807.0602.v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Samet Ozturk ◽

Vasilis Fthenakis ◽

Stefan Faulstich

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Failure Modes ◽

Wind Farms ◽

Weather Conditions ◽

Direct Drive ◽

Climatic Regions ◽

Failure Data ◽

Criticality Analysis ◽

Reliability And Availability

The wind industry is looking for ways to accurately predict the reliability and availability of newly installed wind turbines. Failure modes, effects and criticality analysis (FMECA) is a technique utilized for determining the critical subsystems of wind turbines. There are several studies which applied FMECA for wind turbines in the literature, but no studies so far have considered different weather conditions or climatic regions. Furthermore, various design types of wind turbines have been analyzed applying FMECA but no study so far has applied FMECA to compare the reliability of geared and direct-drive wind turbines. We propose to fill these gaps by using Koppen-Geiger climatic regions and two different turbine models of direct-drive and geared-drive concepts. A case study is applied on German wind farms utilizing the WMEP database which contains wind turbine failure data from 1989 to 2008. This proposed methodology increases the accuracy of reliability and availability predictions and compares different wind turbine design types and eliminates underestimation of impacts of different weather conditions.

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Numerical Study for a Catamaran Gripper-Monopile Mechanism of a Novel Offshore Wind Turbine Assembly Installation Procedure

Volume 9: Offshore Geotechnics; Torgeir Moan Honoring Symposium ◽

10.1115/omae2017-62342 ◽

2017 ◽

Author(s):

Lars Ivar Hatledal ◽

Houxiang Zhang ◽

Karl Henning Halse ◽

Hans Petter Hildre

Keyword(s):

Numerical Simulations ◽

Wind Turbine ◽

Wind Turbines ◽

Numerical Study ◽

Weather Conditions ◽

Rolling Contact ◽

Offshore Wind ◽

Offshore Wind Turbine ◽

Contact Points ◽

Turbine Installation

Current methods for installation of offshore wind turbines are all sensitive to the weather conditions and the present cost level of offshore wind power is more than twice the cost of land-based units, increasing with water depth. This paper presents numerical simulations of a novel experimental gripper design to reduce the environmental effects applied to a catamaran type of vessel during wind turbine installation. In SFI MOVE project in NTNU Aalesund, our team proposed a novel wind turbine installation process. A new catamaran vessel will carry pre-assembled wind turbines to the installation location. Two new designed grippers on the deck will make a lifting operation to install the wind turbine onto the turbine foundation. Three prismatic grippers with several rolling contact points at the end are attached in an arc at the catamaran’s aft, designed to grasp the turbine foundation in order to make a connection between the two in the horizontal plane. This paper will only emphasize the contact responses between the turbine foundation and the three grippers during the wind turbine installation process. Numerical simulations are carried out using the virtual prototyping framework Vicosim which is developed by NTNU Aalesund. The simulation results show validation of a key part of the proposed new wind turbine installation idea.

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Modeling of the atmospheric boundary layer under stability stratification for wind turbine wake production

Wind Engineering ◽

10.1177/0309524x19880929 ◽

2019 ◽

pp. 0309524X1988092

Author(s):

Mohamed Marouan Ichenial ◽

Abdellah El-Hajjaji ◽

Abdellatif Khamlichi

Keyword(s):

Boundary Layer ◽

Atmospheric Boundary Layer ◽

Wind Turbine ◽

Wind Turbines ◽

Large Scale ◽

Wind Farm ◽

Layer Structure ◽

Atmospheric Stability ◽

Weather Conditions ◽

Boundary Layer Structure

The assessment of climatological site conditions, airflow characteristics, and the turbulence affecting wind turbines is an important phase in developing wake engineering models. A method of modeling atmospheric boundary layer structure under atmospheric stability effects is crucial for accurate evaluation of the spatial scale of modern wind turbines, but by themselves, they are incapable to account for the varying large-scale weather conditions. As a result, combining lower atmospheric models with mesoscale models is required. In order to realize a reasonable approximation of initial atmospheric inflow condition used for wake identification behind an NREL 5-MW wind turbine, different vertical wind profile models on equilibrium conditions are tested and evaluated in this article. Wind farm simulator solvers require massive computing resources and forcing mechanisms tendencies inputs from weather forecast models. A three-dimensional Flow Redirection and Induction in Steady-state engineering model was developed for simulating and optimizing the wake losses of different rows of wind turbines under different stability stratifications. The obtained results were compared to high-fidelity simulation data generated by the famous Simulator for Wind Farm Applications. This work showed that a significant improvement related to atmospheric boundary layer structure can be made to develop accurate engineering wake models in order to reduce wake losses.

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Confirming Tonality at Residences Influenced by Wind Turbines

Journal of Energy Conservation ◽

10.14302/issn.2642-3146.jec-20-3359 ◽

2020 ◽

Vol 1 (3) ◽

pp. 13-44

Author(s):

William K.G. Palmer

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Weather Conditions ◽

Correlated Data ◽

Operational Performance ◽

Start Up ◽

Audio Recordings ◽

Recorded Data ◽

Chronic Irritation ◽

Local Weather

For 5 years, since the start-up of an array of 140 wind turbines, residents have filed complaints with the Ontario Ministry of the Environment (the regulator), and K2 Wind (the operator). Residents complained that the turbines produce a tonal sound, and that the irritation this produced impacted their sleep, their health, and the enjoyment of their property. To confirm tonality from the wind turbines, this research examined over 200 data examples from two families. These families collected data by two independent methods, a continuously recording system, and by making selected audio recordings. The recorded data was correlated with the wind turbine operational performance, and local weather conditions. The correlated data was analyzed for tonality using international standard evaluation methods. The analysis confirmed over 84% correlation between complaints of irritating conditions, and tonality from 5 dB to over 20 dB. The research also identified deviation between the recommended method for assessing wind turbine tonality of an expert group panel for the industry and the method for compliance monitoring now prescribed by regulations. The deviation can incorrectly reduce tonality calculated to significantly below the actual tonality. Finally, the results showed that the assumption of the regulator to only require assessment of compliance when the resident was downwind of the nearest wind turbine was incorrect. Most complaints arose from other wind directions. Neither was the regulator’s assumption correct that curtailing the wind turbine operation to continue operating at only partially reduced outputs would give remediation. The research concludes that tonality arises consistent with the wind turbine operation, identifying a critical need to revise the practices to prevent chronic irritation.

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Low-Height Lifting System for Offshore Wind Turbine Installation: Modelling and Hydrodynamic Response Analysis Using the Commercial Simulation Tool SIMA

Volume 1: Offshore Technology ◽

10.1115/omae2020-19183 ◽

2020 ◽

Author(s):

David Vågnes ◽

Thiago Gabriel Monteiro ◽

Karl Henning Halse ◽

Hans Petter Hildre

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Renewable Energy Sources ◽

Weather Conditions ◽

Economic Feasibility ◽

Offshore Wind ◽

Offshore Wind Turbine ◽

Response Analysis ◽

Offshore Wind Turbines ◽

Lifting System

Abstract With the increasing demand for renewable energy sources in the past years, the interest in expanding the use of wind energy has grown. The next frontier in this expansion process is the use of floating wind turbines offshore. One of the main factors dictating the economic feasibility of such wind turbines is the complexity of their installation process. The dimensions of modern offshore wind turbines, the distance from the installation sites to the coast and demanding environmental factors all contribute to the difficult of developing an efficient installation concept for this kind of structures. In this work, we present a new concept for a catamaran vessel capable of handling the deployment of offshore wind turbines on floating spar platforms using a low-height lifting system that connects to the lower end of the wind turbine. The low-height lifting system is controlled by an active heave compensation system and constant tension tugger wires attached to the turbine mid-section are used to ensure the balance of the tower during the installation process. We conducted a series of hydrodynamic analysis using the software suit SIMA to study the dynamic response of the proposed system under different weather conditions and different operational layouts. This preliminary concept was proven feasible from a hydrodynamic point of view and can now be pushed forward for further studies regarding other aspects of the operation, such as impact and structural loads and mechanical design of components.

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Design of a Multi-Robot System for Wind Turbine Maintenance

Energies ◽

10.3390/en13102552 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2552 ◽

Cited By ~ 1

Author(s):

Josef Franko ◽

Shengzhi Du ◽

Stephan Kallweit ◽

Enno Duelberg ◽

Heiko Engemann

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Large Scale ◽

Fiber Composite ◽

Weather Conditions ◽

Mobile Systems ◽

Robot System ◽

Manual Task ◽

Set Up ◽

Multi Robot

The maintenance of wind turbines is of growing importance considering the transition to renewable energy. This paper presents a multi-robot-approach for automated wind turbine maintenance including a novel climbing robot. Currently, wind turbine maintenance remains a manual task, which is monotonous, dangerous, and also physically demanding due to the large scale of wind turbines. Technical climbers are required to work at significant heights, even in bad weather conditions. Furthermore, a skilled labor force with sufficient knowledge in repairing fiber composite material is rare. Autonomous mobile systems enable the digitization of the maintenance process. They can be designed for weather-independent operations. This work contributes to the development and experimental validation of a maintenance system consisting of multiple robotic platforms for a variety of tasks, such as wind turbine tower and rotor blade service. In this work, multicopters with vision and LiDAR sensors for global inspection are used to guide slower climbing robots. Light-weight magnetic climbers with surface contact were used to analyze structure parts with non-destructive inspection methods and to locally repair smaller defects. Localization was enabled by adapting odometry for conical-shaped surfaces considering additional navigation sensors. Magnets were suitable for steel towers to clamp onto the surface. A friction-based climbing ring robot (SMART— Scanning, Monitoring, Analyzing, Repair and Transportation) completed the set-up for higher payload. The maintenance period could be extended by using weather-proofed maintenance robots. The multi-robot-system was running the Robot Operating System (ROS). Additionally, first steps towards machine learning would enable maintenance staff to use pattern classification for fault diagnosis in order to operate safely from the ground in the future.

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