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Community Stakeholder Management in Wind Energy Development Projects : A planning approachDel Rosario, Vilma, Goh, Kar Han January 2008 (has links)
There often exist hard-to-identify or unforeseen external parties that emerge as indirect stakeholders of a project who can significantly influence its execution and outcome. The broader stakeholder landscape in both theory and practice recognizes the local community including other interest groups of a project site as such key stakeholders. However recent cases have revealed shortcomings in managing this category of stakeholders, leading to authoritative rejection of development permit applications and strong local opposition that consequently increase costs and delay to the project. There is indication that a weak community stakeholder management process in the planning stages can cause problems to the project, or worse, in some cases lead to project failure and abandonment by the developer. Wind energy development projects are not exempted from this condition and are possibly even more prone as they involve the erection of tall wind turbines across wide-open landscapes that are deemed controversial and unacceptable to a wider population. Endorsed by the persuasive rationale for wind energy especially in view of the environment and sustainable development, a more comprehensive and effective guidance for community stakeholder management in the planning stage is required to mitigate, if not eliminate, potential issues that can hinder the successful implementation of wind energy development projects. Hence this thesis primarily seeks to answer the research question of: “How should community stakeholders of wind energy development projects be managed in the planning stage prior to permit application?”. Using a qualitative approach to research through interviews with several industry practitioners and reviewing secondary data of industry best practices, policies, literature and case studies, 16 community stakeholder management key conclusion points could be made from research data collected. These points are individually important while in aggregate form a broad and novel framework that serves to further raise the awareness and readiness of wind energy development project managers in their community stakeholder management initiatives. A baseline list of community stakeholders and their common concerns were identified, together with suggested approaches to identify community stakeholders in each project. Community consultation is key to the process and engaging the community as widely and early as possible is recommended. Furthermore, key principles and an array of common methods for community stakeholder management in the planning stages of the project are presented, while acknowledging that not all stakeholders can be satisfied at each instance. Ultimately these findings were consolidated in a community consultation checklist that serves as a more systematic and practical tool in guiding project managers in their community stakeholder management initiatives during planning. The research findings herewith contribute valuable insights to the existing body of knowledge in this area and also provide enhanced practical guidance to project managers in achieving successful community stakeholder management during planning, facilitating higher acceptance for the proposal, carrying out a more efficient and effective planning process and improving the likelihood for project approval from both authoritative and judiciary standpoints.
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Gis-based Site Selection Approach For Wind And Solar Energy Systems: A Case Study From Western TurkeyAydin, Nazli Yonca 01 July 2009 (has links) (PDF)
Many countries around the world integrated Renewable Energy Systems (RES) in their future energy plans in order to reduce negative impacts of fossil fuel consumption on the environment. However, RES may as well cause various environmental problems which are mostly related with the geographic locations of these facilities. The aim of this thesis is to create a Geographic Information System-based methodology for evaluating alternative locations for wind, solar and hybrid power plants by using fuzzy multi-criteria decision making. Environmental objectives and economical feasibility criteria for wind and solar systems are identified through Turkish legislations, previous studies, and interviews with General Directorate of Electrical Power Resources Survey and Development. Individual satisfaction degrees for each alternative location with respect to the identified environmental objectives and economical feasibility criteria are calculated using fuzzy set theory tools. Then these individual satisfaction degrees are aggregated into overall performance indexes which are used to determine priority maps for wind and solar energy generation facilities. Finally, maps of priority sites for wind and solar energy systems are overlaid to identify suitable locations for hybrid wind-solar energy systems. The proposed methodology is applied on a case study area composed of USak, Aydin, Denizli, Mugla, and Burdur provinces.
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Numerical computations of wind turbine wakesIvanell, Stefan S. A. January 2005 (has links)
<p>Numerical simulations using CFD methods are performed for wind turbine applications. The aim of the project is to get a better understanding of the wake behaviour, which is needed since today’s industrial design codes for wind power applications are based on the BEM (Blade Element Momentum) method. This method has been extended with a number of empirical corrections not based on physical flow features. The importance of accurate design models does also increase as the turbines become larger. Therefore, the research is today shifting toward a more fundamental approach, aiming at understanding basic aerodynamic mechanisms. The result from the CFD simulation is evaluated and special interest is given to the circulation and the position of vortices. From these evaluations, it will hopefully be possible to improve the engineering methods and base them, to a greater extent, on physical features instead of empirical corrections.</p><p>The simulations are performed using the program ”EllipSys3D” developed at DTU (The Technical University of Denmark). The Actuator Line Method is used, where the blade is represented by a line instead of a large number of panels. The forces on that line are introduced by using tabulated aerodynamic coefficients. In this way, the computer resource is used more efficiently since the number of node points locally around the blade is decreased, and they can instead be concentrated in the wake behind the blades.</p><p>An evaluation method to extract values of the circulation from the wake flow field is developed.</p><p>The result shows agreement with classical theorems from Helmholtz, from which it follows that the wake tip vortex has the same circulation as the maximum value of the bound circulation on the blade.</p>
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Έλεγχος βήματος πτερυγίου σε ανεμογεννήτρια με σύγχρονη μηχανή μόνιμου μαγνήτηΜοσχονά, Αναστασία 13 January 2015 (has links)
Η διαρκώς αυξανόμενη ζήτηση ηλεκτρικής ενέργειας, στους καιρούς μας, σε συνδυασμό με τη ραγδαία κλιματική αλλαγή, οδηγούν στην ανάγκη αναζήτησης οικονομικών, άφθονων και καθαρών πηγών για την παραγωγή της. Συνεπώς η αιολική ενέργεια κερδίζει έδαφος στις επιλογές των κρατών ανά τον κόσμο. Στην παρούσα διπλωματική θα αναλυθεί μια διάταξη ανεμογεννήτριας, η οποία αποτελείται από μια σύγχρονη μηχανή μόνιμου μαγνήτη (PMSG), έναν μετατροπέα συχνότητας (back-to-back converter) και ένα φίλτρο RL από την πλευρά του δικτύου. Με την επιλογή μας να χρησιμοποιήσουμε σύγχρονη μηχανή μόνιμου μαγνήτη κερδίζουμε σε αποδοτικότητα και αξιοπιστία. Σκοπός την εργασίας αυτής είναι αφενός η μελέτη και η ανάλυση του πλήρους συστήματος στο d-q στρεφόμενο σύστημα καθέτων αξόνων μέσω του μετασχηματισμού Park και αφετέρου η εφαρμογή του κατάλληλου σχεδιασμού ελέγχου, ώστε να επιτευχθεί η μέγιστη απομάστευευση ισχύος από τον άνεμο. Αυτό θα πραγματοποιηθεί λαμβάνοντας υπόψη τους περιορισμούς που θέτουν τα κατασκευαστικά χαρακτηριστικά της γεννήτριας και οι απαιτήσεις του δικτύου. Η προσομοίωση του συνολικού συστήματος θα γίνει στο περιβάλλον του Matlab/Simulink. Μέσω της προσομοίωσης αυτής θα προκύψουν οι αποκρίσεις των βασικών μεγεθών του συστήματος, από τα οποία θα εξαχθούν συμπεράσματα σχετικά με την ποιότητα των επιλογών μας. / The increasing demand for electricity, in our times, combined with the rapid climate change, leads to the need of economical, abundant and clean sources of production. Therefore, wind energy is gaining ground around the world. In this thesis a wind turbine topology will modeled and analyzed. It consists of a permanent magnet synchronous generator (PMSG), a frequency back-to-back converter and an RL filter from the network side. By using a permanent magnet synchronous generator the model becomes efficient and reliable. The initial purpose is studying an analyzing the complete system, using d-q rotating vertical shaft system with Park transformation. Implementation of the appropriate control design will follow, in order to achieve maximum wind power extraction. Constrains, which are posed by the generator contraction characteristics and network requirements, must and will be considered. The simulation of the complete system will take place in Matlab/Simulink computing environment. The responses of the fundamental units will be presented and valuated, in order to extract conclusions regarding the quality of different control methods.
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In-cloud ice accretion modeling on wind turbine blades using an extended Messinger modelAli, Muhammad Anttho 21 September 2015 (has links)
Wind turbines often operate under cold weather conditions where icing may occur. Icing causes the blade sections to stall prematurely reducing the power production at a given wind speed. The unsteady aerodynamic loads associated with icing can accelerate blade structural fatigue and creates safety concerns.
In this work, the combined blade element-momentum theory is used to compute the air loads on the baseline rotor blades, prior to icing. At each blade section, a Lagrangian particle trajectory model is used to model the water droplet trajectories and their impact on the blade surface. An extended Messinger model is next used to solve the conservation of mass, momentum, and energy equations in the boundary layer over the surface, and to determine ice accretion rate. Finally, the aerodynamic characteristics of the iced blade sections are estimated using XFOIL, which initiate the next iteration step for the computation of air loads via combined blade element theory. The procedure repeats until a desired exposure time is achieved. The performance degradation is then predicted, based on the aerodynamic characteristics of the final iced blades.
The 2-D ice shapes obtained are compared against experimental data at several representative atmospheric conditions with acceptable agreement. The performance of a generic experimental wind turbine rotor exposed to icing climate is simulated to obtain the power loss and identify the critical locations on the blade. The results suggest the outboard of the blade is more prone to ice accumulation causing considerable loss of lift at these sections. Also, the blades operating at a higher pitch are expected to accumulate more ice. The loss in power ranges from 10% to 50% of the rated power for different pitch settings under the same operating conditions.
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Skirtingų tipų vėjo jėgainių triukšmo ir jo spektro tyrimai / Noise and its spectra analysis for different types of wind turbinesBudreika, Tadas 28 June 2008 (has links)
Senkantys tradicinio kuro ištekliai, visuotinis klimato šiltėjimas, aplinkos užterštumas radionuklidais, atmosferos užteršimas SOX, NOx bei kitomis kenksmingomis medžiagomis. Tai tik dalis neigiamų tradicinės energetikos pasekmių. Noras turėti pakankamai energijos išteklių tuo nekenkiant aplinkai skatina valdžios institucijas, mokslo bendruomenę ir visuomenę imtis veiksmų, kad būtų sukurtos technologijos, kurios nepriešintų šių dviejų, vienodai svarbių poreikių.
Vėjo energetika – vienas iš būdų, kurio pagalba galima tenkinti energetinius poreikius nedarant aplinkai reikšmingo neigiamo poveikio. Tačiau vėjo energetika – nauja energetikos rūšis, susilaukianti daug kritikos. Todėl labai svarbu nustatyti v��jo energetikos keliamus neigiamus poveikius aplinkai bei žmogui.
Šio tyrimo tikslas išsiaiškinti kaip slopinamas triukšmo lygis tolstant nuo vėjo jėgainės. Tai pat svarbu buvo nustatyti kokio dažnio garso bangas skleidžia skirtingos vėjo jėgainės. Siekiant šio tikslo reikėjo atlikti lauko matavimus vėjo jėgainių aplinkoje.
Rezultatai parodė kad higienos normose nustatyto maksimalaus leistino triukšmo ekvivalentinio lygio (55 dBA) nakties valandoms (22-6 h) nebuvo nustatyta netgi tyrimus atliekant dienos metu, kai vėjo greitis siekė 8m/s.
Nustatyta, kad esant 7m/s vėjo greičiui vėjo jėgainė Vestas V100 skleidė 315Hz – 630Hz dažnio garso bangas. Esant 8m/s vėjo greičiui vėjo jėgainė Enercon E40 skleidė 250Hz - 2000Hz dažnio garso bangas.
Esant 3 m/s vėjo greičiui vėjo jėgainė... [toliau žr. visą tekstą] / Decreasing resources of traditional fuels, global climate warming, radioactive environmental pollution, air polluted with SOX, NOX and other toxic substances. It’s just a little piece of negative effect of traditional energy production. Aim to have enough energy without harming the environment encourage government institutions, scientists and public take action to design technology that could supply humankind with energy without polluting the environment as today’s energy production does.
Wind energy – one of the ways we can satisfy energy needs without significant side effect for environment and human. Wind energy is still a new kind of energy production witch receive much critics from skeptics. That’s why it is so important to estimate the side effects for environment and human.
Aim of this study is to estimate attenuation of sound. Also it was important to compare the frequency range witch different wind turbine emits. Field study was carried out to measure the sound pressure levels in the near distances from the wind turbines.
Results show that threshold for noise limit for a night period wasn’t breached even then the measurements were taken in daytime, with 8 m/s wind speed.
It was estimated that in 7 m/s wind speed wind turbine Vestas V100 emitted 315Hz – 630Hz frequency sound. In the wind speed of 8 m/s wind turbine Enercon E40 emitted 250Hz - 2000Hz frequency sound.
In the wind speed of 3 m/s wind turbine Enercon E70 was responsible for higher values of 12,5Hz - 63... [to full text]
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Coupled Dynamic Analysis of Multiple Unit Floating Offshore Wind TurbineBae, Yoon Hyeok 03 October 2013 (has links)
In the present study, a numerical simulation tool has been developed for the rotor-floater-tether coupled dynamic analysis of Multiple Unit Floating Offshore Wind Turbine (MUFOWT) in the time domain including aero-blade-tower dynamics and control, mooring dynamics and platform motion. In particular, the numerical tool developed in this study is based on the single turbine analysis tool FAST, which was developed by National Renewable Energy Laboratory (NREL). For linear or nonlinear hydrodynamics of floating platform and generalized-coordinate-based FEM mooring line dynamics, CHARM3D program, hull-riser-mooring coupled dynamics program developed by Prof. M.H. Kim’s research group during the past two decades, is incorporated. So, the entire dynamic behavior of floating offshore wind turbine can be obtained by coupled FAST-CHARM3D in the time domain. During the coupling procedure, FAST calculates all the dynamics and control of tower and wind turbine including the platform itself, and CHARM3D feeds all the relevant forces on the platform into FAST. Then FAST computes the whole dynamics of wind turbine using the forces from CHARM3D and return the updated displacements and velocities of the platform to CHARM3D.
To analyze the dynamics of MUFOWT, the coupled FAST-CHARM3D is expanded more and re-designed. The global matrix that includes one floating platform and a number of turbines is built at each time step of the simulation, and solved to obtain the entire degrees of freedom of the system. The developed MUFOWT analysis tool is able to compute any type of floating platform with various kinds of horizontal axis wind turbines (HAWT). Individual control of each turbine is also available and the different structural properties of tower and blades can be applied. The coupled dynamic analysis for the three-turbine MUFOWT and five-turbine MUFOWT are carried out and the performances of each turbine and floating platform in normal operational condition are assessed. To investigate the coupling effect between platform and each turbine, one turbine failure event is simulated and checked. The analysis shows that some of the mal-function of one turbine in MUFOWT may induce significant changes in the performance of other turbines or floating platform. The present approach can directly be applied to the development of the remote structural health monitoring system of MUFOWT in detecting partial turbine failure by measuring tower or platform responses in the future.
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Optimally-Sized Design of a Wind/Diesel/Fuel Cell Hybrid System for a Remote CommunityVafaei, Mehdi 29 September 2011 (has links)
Remote communities, characterized by no connection to the main power grid, traditionally get their power from diesel generators. Long geographical distances and lack of suitable roads make the fuel transportation difficult and costly, increasing the final cost of electricity. A microgrid using renewable energy as the main source can serve as a viable solution for this problem with considerable economical and environmental benefits. The focus of this research is to develop a microgrid for a remote community in northern Ontario (Canada) that combines wind, as a renewable source of energy, and a hydrogen-based energy storage system, with the goal of meeting the demand, while minimizing the cost of energy and adverse effect on the environment. The existing diesel generators remain in the system, but their use is minimized.
The microgrid system studied in this research uses a wind turbine to generate electricity, an electrolyser to absorb the excess power from the wind source, a hydrogen tank to store the hydrogen generated by the electrolyser, a fuel cell to supply the demand when the wind resource is not adequate, and a diesel generator as a backup power.
Two scenarios for unit-sizing are defined and their pros. and cons. are discussed. The economic evaluation of scenarios is performed and a cost function for the system is defined. The optimization problem thus formulated is solved by solvers in GAMS. The inputs are wind profile of the area, load profile of the community, existing sources of energy in the area, operating voltage of the grid, and sale price of electricity in the area. The outputs are the size of the fuel cell and electrolyser units that should be used in the microgrid, the capital and running costs of each system, the payback period of the system, and cost of generated electricity. Following this, the best option for the microgrid structure and component sizes for the target community is determined.
Finally, a MATLAB-based dynamic simulation platform for the system under study with similar load/wind profile and sizing obtained in optimization problem is developed and the dynamic behaviour of microgrid at different cases is studied.
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Development of biomimetic control strategies for the optimal use of renewable sources and energy storage systems /Hapke, Hannes Max. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 108-114). Also available on the World Wide Web.
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Ανάλυση υπερτάσεων από εγκαταστάσεις ανανεώσιμων πηγών ενέργειας σε δίκτυα υψηλών τάσεων με το ΕΜΤΡΚαστανός, Γεώργιος 19 May 2011 (has links)
Σκοπός της εργασίας είναι η μελέτη φαινομένων υπερτάσεων σε δίκτυα σύνδεσης ανανεώσιμων πηγών ενέργειας με τη χρησιμοποίηση του προγράμματος ΕΜΤΡ. Μέσω της ιδιαίτερης αναφοράς σε αιολικά συστήματα γίνεται λεπτομερής εξομοίωση για δυναμικές και διακοπτικές υπερτάσεις, υπερτάσεις χειρισμών, καθώς και κεραυνικές υπερτάσεις. / The purpose of this study is the presentation and analysis of overvoltages occurring in the network interconnection of renewable energy resources. Through the detailed reference of wind power systems, the thorough study of lighting,dynamic and switching overvoltages is presented.
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