2,260,909 research outputs found
Select Committee on Wind Turbines final report
Get PDFThe committee recommends the Commonwealth Government create an Independent Expert Scientific Committee on Industrial Sound responsible for providing research and advice to the Minister for the Environment on the impact on human health of audible noise (including low frequency) and infrasound from wind turbines.
Recommendation 1: final
6.5 The committee recommends that an Independent Expert Scientific Committee on Industrial Sound (IESC) be established by law, through provisions similar to those which provide for the Independent Expert Scientific Committee on Coal Seam Gas and Large Coal Mining Development.
6.6 The provisions establishing the IESC on Industrial Sound should state that the Scientific Committee must conduct \u27independent, multi-disciplinary research into the adverse impacts and risks to individual and community health and wellbeing associated with wind turbine projects and any other industrial projects which emit sound and vibration energy\u27
Optimal Management of a Wind/CAES Power Plant by means of Neural Network Wind Speed Forecast
No full textSome of the major limitations of renewable energy sources are represented by their low power density and intermittent nature, largely depending upon local site and unpredictable weather conditions. These problems concur to increase the unit costs of wind power, so limiting their diffusion and the benefits due to the reduced exploitation of fossil resources. By coupling storage systems with a wind farm, some of the major limitations of wind power, such as a low power density and an unpredictable nature, can be overcome.
Furthermore, the use of time-series neural network-based prediction models aims at reducing the stochastic uncertainty of wind power.
A Matlab/Simulink model of a hybrid power plant consisting of a wind farm coupled with Compressed Air Energy Storage (CAES) is presented.
In CAES energy is stored in the form of compressed air in a reservoir during off-peak periods, while it is used on demand during peak periods to generate power with a turbo-generator system. Such plants can offer significant benefits in terms of flexibility in matching a fluctuating power demand, particularly when coupled with renewable sources.
The model employs neural network-based wind speed forecasting to determine the optimal daily operation strategy for the storage system.
Without predicting the incoming wind energy, the net load, above that provided by wind turbines, would be known only in real time. Thus, the only way to manage CAES storage/generation would be to follow the net load for a prefixed number of hours; the operation of CAES would be function of the load, of the wind power generation and the energy prices. Because wind speed is variable and not predictable, plant management can be a problem. Mainly, user demand might not be satisfied during some periods. So, forecasting the wind contribution could be very helpful for proper system management. Knowing the incoming wind power several hours in advance helps in estimating the net load for the current day and thus determining the management strategy.
As shown in the paper, the knowledge of the expected available energy is a key factor to optimize the management strategies of the proposed hybrid power plant.
A detailed economic analysis has been carried out: investment and maintenance costs are estimated based on literature data, while operational costs and revenues are calculated according to the energy market prices
Pedestrian level wind environment around isolated buildings resulted from twisted wind profiles
No full textThe pedestrian-level wind environment influenced by twisted wind profiles were evaluated through a series of wind tunnel tests. In the tests, more than 200 Irwin sensors were installed to measure the wind speeds at pedestrian level around five isolated buildings, each with different dimensions. Two twisted wind profiles, with a maximum twist angle of 13° and 22° respectively, were simulated in boundary-layer wind tunnel. A conventional log-law type turbulent a boundary layer profile was employed to repeat the wind tunnel test to act as a control case. Based on the wind speeds measurements, the velocity ratios (VR) were calculated to show the influence of the twisted profiles. By comparing the VR distributions under the influence of the two twisted profiles to the VR distributions in the conventional wind profile, it is observed that (a) the VR distribution in the wake zone is skewed according to the maximum twisted angle, (b) the over-speed area (VR>1.2) decreases and the shelter area (VR<0.8) increases in the pedestrian-level wind field under the influence of the twisted profiles
Determination of wind turbine far wake using actuator disk
Get PDFThe growth in size of wind turbines over the last years is significant. The rotor diameter becomes somehow comparable to atmospheric boundary layer at the land surface. In this case the assumption of uniform velocity of upcoming wind cannot be valid. The aim of this paper is to create a simplified model of wind turbine rotor which can represent the aerodynamic inter-action of atmospheric boundary layer with a horizontal axis wind turbine. Such model will be also useful for the study of optimal placement of wind turbines in a wind farm when a large number of calculations is needed and when the time required for full CFD calculations be-comes prohibitive. In this study we adopt actuator disk model which takes in account with sufficient precision the influence of blade geometry on wind turbine aerodynamic performance. The proposed actuator disk model is tested in the case of horizontal axis wind turbine using wall-modelled large eddy simulation. The obtained results of aerodynamic performance and wake show the rapidity of calculation and the reliability of proposed approach
Motion-induced wind forces of a slender prism
No full textThe motion-induced wind forces of a slender prism were investigated using a forced vibration technique. The prism was driven to oscillate by an actuator in cross-wind direction and the unsteady distributed pressures, under different wind velocities and oscillations, were measured. The unsteady generalized and local aerodynamic force coefficients and the motion-correlated force coefficients of the prism, which are functions of reduced wind velocity and oscillation, were analyzed. It shows that the effects of structural motion on the unsteady force coefficients are significant in the cross-wind direction while the effects are slight in the along-wind direction. Furthermore, in the cross-wind direction, the coefficients tend to increase with oscillating amplitudes at low wind speeds while they are at a quasi-steady state at high wind speeds. The study advances the understanding of the effect of structural motion on three-dimensional prisms, which can be utilized to improve response predictions of the prisms
Investigation of wind turbine flow and wake
Get PDFThis paper is dedicated to the investigation and analysis of wind turbine wake. An experimental work is undertaken in wind tunnel on a horizontal axis wind turbine model. The velocity field in the wake is measured using PIV with phase synchronization in order to relate velocity and vortices to the rotating blades. The tip vortices are investigated in successive azimuthal positions of the rotor. A specially developed algorithm based on the circulation maximum detects the positions of the vortex cores and permits to use conditional averaging technique. The analysis of obtained velocity fields enables to determine the vortex core diameter, the swirl velocity distribution and the vortex diffusion as functions of the vortex age. The quality of obtained results permits to use them as reference for the validation of numerical computations
e-wind: An Integrated Engineering Solution Package for Wind Sensitive Buildings and Structures
No full textThis article introduces "e-wind" program that is currently under development at Wind Engineering Research Center at Tamkang University. e-wind is an effort to integrate the available wind engineering tools, such as wind code, aerodynamic database and analytical procedure, towards an efficient wind resistant design process for building designers. Special IT tools, such as Artificial Neural Network and Expert System are
used to integrate all the components together forming a solution package that can be used by an average structural engineer. The latest information and web technologies were adopted to construct a user friendly interface so that the system would be easily accessible and constantly updated. The current status of the wind engineering components and the IT keys for e-wind are briefly discussed.紙本紙
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Wind Energy Applications Guide
Get PDFThe brochure is an introduction to various wind power applications for locations with underdeveloped transmission systems, from remote water pumping to village electrification. It includes an introductory section on wind energy, including wind power basics and system components and then provides examples of applications, including water pumping, stand-alone systems for home and business, systems for community centers, schools, and health clinics, and examples in the industrial area. There is also a page of contacts, plus two specific example applications for a wind-diesel system for a remote station in Antarctica and one on wind-diesel village electrification in Russia
Experimental study of yawed inflow around wind turbine rotor
Get PDFIn this article, we present an experimental study in a wind tunnel of a three-bladed, Rutland 503 model, horizontal axis yawed wind turbine. Power measurement and an exploration downstream wake of the turbine using particle image velocimetry measurements are performed. The variation of power coefficient as a function of rotational velocity is presented for different yaw angles. The results show a loss of power from the wind turbine when the yaw angle increases. The velocity field of the downstream wake of the rotor is presented in an azimuth plane, which passes through the symmetry axis of the rotor. The instantaneous velocity field is measured and recorded to allow for obtaining the averaged velocity field. The results also show variations in the wake downstream due to decelerating flow caused by the yawed turbine rotor. Analysis of this data shows that the active control of yaw angles could be an advantage to preserve the power from the wind turbine and that details near rotor wake are important for wake theories and topredict the performance of wind turbines as well
Improved cost energy comparison of permanent magnet generators for large offshore wind turbines
No full textThis paper investigates geared and direct-drive permanent magnet generators for a typical offshore wind turbine, providing a detailed comparison of various wind turbine drivetrain configurations in order to minimise the Cost of Energy. The permanent magnet generator topologies considered include a direct-drive machine and single stage, two-stage or three-stage gearbox driven generators. The cost of energy calculations are based on initial capital costs, the costs of manufacture, installation, operations and maintenance, with particular focus on improved calculations of the annual energy yield with better availability estimations and gearbox loss modelling
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