WorldWideScience

Sample records for wind motional electric

  1. Wind power. [electricity generation

    Science.gov (United States)

    Savino, J. M.

    1975-01-01

    A historical background on windmill use, the nature of wind, wind conversion system technology and requirements, the economics of wind power and comparisons with alternative systems, data needs, technology development needs, and an implementation plan for wind energy are presented. Considerable progress took place during the 1950's. Most of the modern windmills feature a wind turbine electricity generator located directly at the top of their rotor towers.

  2. Wind electric power generation

    International Nuclear Information System (INIS)

    Koch, M.K.; Wind, L.; Canter, B.; Moeller, T.

    2001-01-01

    The monthly statistics of wind electric power generation in Denmark are compiled from information given by the owners of the private wind turbines. For each wind turbine the name of the site and of the type of turbine is given, and the power generation data are given for the month in question together with the total production in 1999 and 2000. Also the data of operation start are given. On the map of Denmark the sites of the wind turbines are marked. (CLS)

  3. Colliding Stellar Wind Models with Orbital Motion

    Science.gov (United States)

    Wilkin, Francis P.; O'Connor, Brendan

    2018-01-01

    We present thin-shell models for the collision between two ballistic stellar winds, including orbital motion.The stellar orbits are assumed circular, so that steady-state solutions exist in the rotating frame, where we include centrifugal and Coriolis forces. Exact solutions for the pre-shock winds are incorporated. Here we discuss 2-D model results for equal wind momentum-loss rates, although we allow for the winds to have distinct speeds and mass loss rates. For these unequal wind conditions, we obtain a clear violation of skew-symmetry, despite equal momentum loss rates, due to the Coriolis force.

  4. Wind/Hybrid Electricity Applications

    Energy Technology Data Exchange (ETDEWEB)

    McDaniel, Lori [Iowa Department of Natural Resources, Des Moines, IA (United States)

    2001-03-01

    Wind energy is widely recognized as the most efficient and cost effective form of new renewable energy available in the Midwest. New utility-scale wind farms (arrays of large turbines in high wind areas producing sufficient energy to serve thousands of homes) rival the cost of building new conventional forms of combustion energy plants, gas, diesel and coal power plants. Wind energy is not subject to the inflationary cost of fossil fuels. Wind energy can also be very attractive to residential and commercial electric customers in high wind areas who would like to be more self-sufficient for their energy needs. And wind energy is friendly to the environment at a time when there is increasing concern about pollution and climate change. However, wind energy is an intermittent source of power. Most wind turbines start producing small amounts of electricity at about 8-10 mph (4 meters per second) of wind speed. The turbine does not reach its rated output until the wind reaches about 26-28 mph (12 m/s). So what do you do for power when the output of the wind turbine is not sufficient to meet the demand for energy? This paper will discuss wind hybrid technology options that mix wind with other power sources and storage devices to help solve this problem. This will be done on a variety of scales on the impact of wind energy on the utility system as a whole, and on the commercial and small-scale residential applications. The average cost and cost-benefit of each application along with references to manufacturers will be given. Emerging technologies that promise to shape the future of renewable energy will be explored as well.

  5. Survey of wind power potential for wind-based electricity

    African Journals Online (AJOL)

    Mgina

    2006-12-31

    Dec 31, 2006 ... ABSTRACT. The potential for wind-generated electricity is examined using 22 months wind data collected from a prospective site located in the southern highlands of Tanzania. While the data for the year 2001 was from March to December that of 2002 was for all the twelve months of the year.

  6. Wind power bidding in electricity markets with high wind penetration

    International Nuclear Information System (INIS)

    Vilim, Michael; Botterud, Audun

    2014-01-01

    Highlights: • We analyze the pricing systems and wind power trading in electricity markets. • We propose a model that captures the relation between market prices and wind power. • A probabilistic bidding model can increase profits for wind power producers. • Profit maximizing bidding strategies carry risks for power system operators. • We conclude that modifications of current market designs may be needed. - Abstract: Objective: The optimal day-ahead bidding strategy is studied for a wind power producer operating in an electricity market with high wind penetration. Methods: A generalized electricity market is studied with minimal assumptions about the structure of the production, bidding, or consumption of electricity. Two electricity imbalance pricing schemes are investigated, the one price and the two price scheme. A stochastic market model is created to capture the price effects of wind power production and consumption. A bidding algorithm called SCOPES (Supply Curve One Price Estimation Strategy) is developed for the one price system. A bidding algorithm called MIMICS (Multivariate Interdependence Minimizing Imbalance Cost Strategy) is developed for the two price system. Results: Both bidding strategies are shown to have advantages over the assumed “default” bidding strategy, the point forecast. Conclusion: The success of these strategies even in the case of high deviation penalties in a one price system and the implicit deviation penalties of the two price system has substantial implications for power producers and system operators in electricity markets with a high level of wind penetration. Practice implications: From an electricity market design perspective, the results indicate that further penalties or regulations may be needed to reduce system imbalance

  7. Compatibility Between Electric Components in Wind Farms

    DEFF Research Database (Denmark)

    Holdyk, Andrzej; Holbøll, Joachim; Arana Aristi, Iván

    2011-01-01

    The paper describes a method for investigation of the compatibility between electric components in wind farms by identifying critical resonances at different points of an offshore wind farm (OWF), based on systematic variation of critical parameters. In this way, the design of future OWF can...

  8. Electrical Aspects of Wind Turbines

    DEFF Research Database (Denmark)

    Chen, Zhe; Blaabjerg, Frede

    2009-01-01

    This is the most authoritative single volume on offshore wind power yet published. Distinguished experts, mainly from Europe's leading universities, have contributed a collection of peer reviewed papers on the interfaces between wind power technology and marine engineering. The range of issues...

  9. The impact of wind power on electricity prices

    Energy Technology Data Exchange (ETDEWEB)

    Brancucci Martinez-Anido, Carlo; Brinkman, Greg; Hodge, Bri-Mathias

    2016-08-01

    This paper investigates the impact of wind power on electricity prices using a production cost model of the Independent System Operator - New England power system. Different scenarios in terms of wind penetration, wind forecasts, and wind curtailment are modeled in order to analyze the impact of wind power on electricity prices for different wind penetration levels and for different levels of wind power visibility and controllability. The analysis concludes that electricity price volatility increases even as electricity prices decrease with increasing wind penetration levels. The impact of wind power on price volatility is larger in the shorter term (5-min compared to hour-to-hour). The results presented show that over-forecasting wind power increases electricity prices while under-forecasting wind power reduces them. The modeling results also show that controlling wind power by allowing curtailment increases electricity prices, and for higher wind penetrations it also reduces their volatility.

  10. Optimal electricity market for wind power

    International Nuclear Information System (INIS)

    Holttinen, H.

    2005-01-01

    This paper is about electricity market operation when looking from the wind power producers' point of view. The focus in on market time horizons: how many hours there is between the closing and delivering the bids. The case is for the Nordic countries, the Nordpool electricity market and the Danish wind power production. Real data from year 2001 was used to study the benefits of a more flexible market to wind power producer. As a result of reduced regulating market costs from better hourly predictions to the market, wind power producer would gain up to 8% more if the time between market bids and delivery was shortened from the day ahead Elspot market (hourly bids by noon for 12-36 h ahead). An after sales market where surplus or deficit production could be traded 2 h before delivery could benefit the producer almost as much, gaining 7%

  11. Price volatility in wind dominant electricity markets

    DEFF Research Database (Denmark)

    Farashbashi-Astaneh, Seyed-Mostafa; Chen, Zhe

    2013-01-01

    High penetration of intermittent renewable energy sources causes price volatility in future electricity markets. This is specially the case in European countries that plan high penetration levels. This highlights the necessity for revising market regulations and mechanisms in accordance...... electricity markets. High price volatility is unappreciated because it imposes high financial risk levels to both electricity consumers and producers. Additionally high price variations impede tracking price signals by consumers in future smart grid and jeopardize implementation of demand response concepts....... The main contribution of this paper is to quantify volatility patterns of electricity price, as penetration level of wind power increases. Results explain a direct relationship between wind penetration and electricity price volatility in a quantitative manner....

  12. Global potential for wind-generated electricity.

    Science.gov (United States)

    Lu, Xi; McElroy, Michael B; Kiviluoma, Juha

    2009-07-07

    The potential of wind power as a global source of electricity is assessed by using winds derived through assimilation of data from a variety of meteorological sources. The analysis indicates that a network of land-based 2.5-megawatt (MW) turbines restricted to nonforested, ice-free, nonurban areas operating at as little as 20% of their rated capacity could supply >40 times current worldwide consumption of electricity, >5 times total global use of energy in all forms. Resources in the contiguous United States, specifically in the central plain states, could accommodate as much as 16 times total current demand for electricity in the United States. Estimates are given also for quantities of electricity that could be obtained by using a network of 3.6-MW turbines deployed in ocean waters with depths <200 m within 50 nautical miles (92.6 km) of closest coastlines.

  13. Parallel electric fields from ionospheric winds

    International Nuclear Information System (INIS)

    Nakada, M.P.

    1987-01-01

    The possible production of electric fields parallel to the magnetic field by dynamo winds in the E region is examined, using a jet stream wind model. Current return paths through the F region above the stream are examined as well as return paths through the conjugate ionosphere. The Wulf geometry with horizontal winds moving in opposite directions one above the other is also examined. Parallel electric fields are found to depend strongly on the width of current sheets at the edges of the jet stream. If these are narrow enough, appreciable parallel electric fields are produced. These appear to be sufficient to heat the electrons which reduces the conductivity and produces further increases in parallel electric fields and temperatures. Calculations indicate that high enough temperatures for optical emission can be produced in less than 0.3 s. Some properties of auroras that might be produced by dynamo winds are examined; one property is a time delay in brightening at higher and lower altitudes

  14. Pricing Electricity in Pools With Wind Producers

    DEFF Research Database (Denmark)

    Morales González, Juan Miguel; Conejo, A. J.; Kai Liu

    2012-01-01

    This paper considers an electricity pool that includes a significant number of wind producers and is cleared through a network-constrained auction, one day in advance and on an hourly basis. The hourly auction is formulated as a two-stage stochastic programming problem, where the first stage...

  15. Development of electric machines with superconducting windings

    International Nuclear Information System (INIS)

    Glebov, I.A.; Novitskij, V.G.

    1977-01-01

    Some studies are discussed performed in the USSR with the aim to develop the most promising electrical machines with superconducting windings, i.e. powerful (more than 1 MW) cryoturbogenerators for power heat and nuclear plants, electric motors of more than 10,000 kW, reverse systems of an electric driver and unipolar generators for electrolysis industry. The design and performances of the simulator of a 1500 kW cryoturbogenerator are given. Problems of coooling and oscillations of the simulator rotor are considered

  16. Wind speed and direction shears with associated vertical motion during strong surface winds

    Science.gov (United States)

    Alexander, M. B.; Camp, D. W.

    1984-01-01

    Strong surface winds recorded at the NASA 150-Meter Ground Winds Tower facility at Kennedy Space Center, Florida, are analyzed to present occurrences representative of wind shear and vertical motion known to be hazardous to the ascent and descent of conventional aircraft and the Space Shuttle. Graphical (percentage frequency distributions) and mathematical (maximum, mean, standard deviation) descriptions of wind speed and direction shears and associated updrafts and downdrafts are included as functions of six vertical layers and one horizontal distance for twenty 5-second intervals of parameters sampled simultaneously at the rate of ten per second during a period of high surface winds.

  17. Wind farm electrical power production model for load flow analysis

    International Nuclear Information System (INIS)

    Segura-Heras, Isidoro; Escriva-Escriva, Guillermo; Alcazar-Ortega, Manuel

    2011-01-01

    The importance of renewable energy increases in activities relating to new forms of managing and operating electrical power: especially wind power. Wind generation is increasing its share in the electricity generation portfolios of many countries. Wind power production in Spain has doubled over the past four years and has reached 20 GW. One of the greatest problems facing wind farms is that the electrical power generated depends on the variable characteristics of the wind. To become competitive in a liberalized market, the reliability of wind energy must be guaranteed. Good local wind forecasts are therefore essential for the accurate prediction of generation levels for each moment of the day. This paper proposes an electrical power production model for wind farms based on a new method that produces correlated wind speeds for various wind farms. This method enables a reliable evaluation of the impact of new wind farms on the high-voltage distribution grid. (author)

  18. Multi-winding homopolar electric machine

    Science.gov (United States)

    Van Neste, Charles W

    2012-10-16

    A multi-winding homopolar electric machine and method for converting between mechanical energy and electrical energy. The electric machine includes a shaft defining an axis of rotation, first and second magnets, a shielding portion, and a conductor. First and second magnets are coaxial with the shaft and include a charged pole surface and an oppositely charged pole surface, the charged pole surfaces facing one another to form a repulsive field therebetween. The shield portion extends between the magnets to confine at least a portion of the repulsive field to between the first and second magnets. The conductor extends between first and second end contacts and is toroidally coiled about the first and second magnets and the shield portion to develop a voltage across the first and second end contacts in response to rotation of the electric machine about the axis of rotation.

  19. Overall Optimization for Offshore Wind Farm Electrical System

    DEFF Research Database (Denmark)

    Hou, Peng; Hu, Weihao; Chen, Cong

    2017-01-01

    Based on particle swarm optimization (PSO), an optimization platform for offshore wind farm electrical system (OWFES) is proposed in this paper, where the main components of an offshore wind farm and key technical constraints are considered as input parameters. The offshore wind farm electrical s...

  20. Sharing wind power forecasts in electricity markets: A numerical analysis

    DEFF Research Database (Denmark)

    Exizidis, Lazaros; Pinson, Pierre; Kazempour, Jalal

    2016-01-01

    In an electricity pool with significant share of wind power, all generators including conventional and wind power units are generally scheduled in a day-ahead market based on wind power forecasts. Then, a real-time market is cleared given the updated wind power forecast and fixed day-ahead decisi...

  1. Gas-fired wind power and electric hydrogen

    NARCIS (Netherlands)

    Hemmes, K.

    2006-01-01

    In the seemingly endless discussions about the pros and cons of wind power even its advocates have to agree that though wind can fly, with offshore wind farms soon to become reality, this only exacerbates the problem of the winds changeability. Even now the major producers of electricity and power

  2. Electric conductivity of plasma in solar wind

    Science.gov (United States)

    Chertkov, A. D.

    1995-01-01

    One of the most important parameters in MHD description of the solar wind is the electric conductivity of plasma. There exist now two quite different approaches to the evaluation of this parameter. In the first one a value of conductivity taken from the most elaborated current theory of plasma should be used in calculations. The second one deals with the empirical, phenomenological value of conductivity. E.g.: configuration of interplanetary magnetic field, stretched by the expanding corona, depends on the magnitude of electrical conductivity of plasma in the solar wind. Knowing the main empirical features of the field configuration, one may estimate the apparent phenomenological value of resistance. The estimations show that the electrical conductivity should be approximately 10(exp 13) times smaller than that calculated by Spitzer. It must be noted that the empirical value should be treated with caution. Due to the method of its obtaining it may be used only for 'large-scale' description of slow processes like coronal expansion. It cannot be valid for 'quick' processes, changing the state of plasma, like collisions with obstacles, e.g., planets and vehicles. The second approach is well known in large-scale planetary hydrodynamics, stemming from the ideas of phenomenological thermodynamics. It could formulate real problems which should be solved by modern plasma physics, oriented to be adequate for complicated processes in space.

  3. statistical analysis of wind speed for electrical power generation

    African Journals Online (AJOL)

    HOD

    1, 4, 5 DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING, UNIVERSITY OF ILORIN, KWARA STATE, NIGERIA. 2DEPARTMENT OF ... Keywords: Wind speed - probability - density function – wind energy conversion system- statistical analyses. 1. ..... weather data for energy assessments of hybrid.

  4. Electric solar wind sail mass budget model

    Directory of Open Access Journals (Sweden)

    P. Janhunen

    2013-02-01

    Full Text Available The electric solar wind sail (E-sail is a new type of propellantless propulsion system for Solar System transportation, which uses the natural solar wind to produce spacecraft propulsion. The E-sail consists of thin centrifugally stretched tethers that are kept charged by an onboard electron gun and, as such, experience Coulomb drag through the high-speed solar wind plasma stream. This paper discusses a mass breakdown and a performance model for an E-sail spacecraft that hosts a mission-specific payload of prescribed mass. In particular, the model is able to estimate the total spacecraft mass and its propulsive acceleration as a function of various design parameters such as the number of tethers and their length. A number of subsystem masses are calculated assuming existing or near-term E-sail technology. In light of the obtained performance estimates, an E-sail represents a promising propulsion system for a variety of transportation needs in the Solar System.

  5. The design of wind turbine for electrical power generation in Malaysian wind characteristics

    International Nuclear Information System (INIS)

    Abas Ab Wahab; Chong Wen Thong

    2000-01-01

    The paper describes the study of a wind turbine for electrical power generation in Malaysia wind characteristics. In this research, the wind turbine is designs based on the local wind characteristics and tries to avoid the problems faced in the past (turbine design, access, manpower and technical). The new wind turbine rotor design for a medium speed wind speed turbine utilises the concept of open-close type of horizontal axis (up-wind) wind turbine is intended to widen the optimum performance range for electrical generation in Malaysia wind characteristics. The wind turbine has been designed to cut-in at a lower speed, and to provide the rotation speed that high enough to run a generator. The analysis and design of new low speed wind turbine blades and open-close turbine rotor and prediction of turbine performance are being detailed in this paper. (Author)

  6. Wind Power in Electrical Distribution Systems

    DEFF Research Database (Denmark)

    Chen, Zhe

    2013-01-01

    Recent years, wind power is experiencing a rapid growth, large number of wind turbines/wind farms have been installed and connected to power systems. In addition to the large centralised wind farms connected to transmission grids, many distributed wind turbines and wind farms are operated...... as distributed generators in distribution systems. This paper discusses the issues of wind turbines in distribution systems. Wind power conversion systems briefly introduced, the basic features and technical characteristics of distributed wind power system are described, and the main technical demands...

  7. Extreme Motion Predictions for Deepwater TLP Floaters for Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Mansour, A. E.

    2006-01-01

    The paper addresses the calculation of extreme motion of a TLP type of floater for an offshore wind turbine. Motions are of significant importance for the operation of the wind turbine as they influence the blade loadings and hence the downtime of the wind turbine energy production. The paper ill...

  8. Wind energy. To produce electricity with the wind

    International Nuclear Information System (INIS)

    Bareau, Helene

    2015-11-01

    This guide addresses the different aspects of wind-based power generation. It outlines the role of wind energy to meet objectives related to the share of renewable energies in the French energy mix, that wind energy is actually replacing fossil energies, that it is based on local resources within higher safety and less wastage, that current advances are made to integrate wind energy production into the grid, and that it is a solution to diversify energy production. Some figures are presented and commented, regarding onshore wind energy production in France, the location of wind farms, and wind energy production in comparison with other renewable sources. The operation of a wind turbine is described and the different types of wind turbines are evoked. The issue of wind farm planning with citizen participation is addressed: regional planning, studies of pre-feasibility for location selection, procedure, and content of the impact study (radars, fauna and flora, landscapes, safety, health). Other features are outlined: a planned dismantling, and a globally favourable perception. The next part addresses offshore wind energy: the interesting potential of stronger and more reliable wind at sea (European situation, French opportunities, elements comprised in an offshore wind farm), impacts (on marine ecosystems, on neighbouring localities, and interests for visitors). Economic aspects are then addressed: cost and profitability, economic spin-offs, and perspectives. The last part concerns individuals and the possibilities to participate to wind farm projects or to invest in small wind turbines with some prerequisites (constant and steady winds, installation assessment, required expertise, indispensable preliminary steps, costs, aids and profitability)

  9. Wind energy for electricity generation in Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Fernando, W.J.

    1988-01-01

    Different aspects of the island Sri Lanka are discussed in relation to the use of wind energy to generate electric power. The electricity demand and supply are dealt with as well as geo-climatic features. Wind resources in different parts of Sri Lanka are determined. Further study is needed to achieve more data on wind potential and wind speeds. Finally a case study is discussed, carried out to assess the feasibility of integration of wind and hydro resources in combination to meet a predetermined load to be used in an optimal configuration. 7 figs., 1 tab.

  10. Small Wind Electric Systems: A South Dakota Consumer's Guide

    International Nuclear Information System (INIS)

    O'Dell, K.

    2001-01-01

    The South Dakota Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a state wind resource map and a list of state incentives and state contacts for more information

  11. Small Wind Electric Systems: An Illinois Consumer's Guide

    International Nuclear Information System (INIS)

    O'Dell, K.

    2001-01-01

    The Illinois Consumer's Guide for Small Wind Electric Systems provides consumers with enough information to help them determine if a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include: how to make your home more energy efficient, how to choose the right size turbine, the parts of a wind electric system, determining if there is enough wind resource on your site, choosing the best site for your turbine, connecting your system to the utility grid, and if it's possible to become independent of the utility grid using wind energy. The cover of the guide contains a wind resource map for Illinois and a list of state incentives and state contacts for more information

  12. Electric Control Substituting Pitch Control for Large Wind Turbines

    Directory of Open Access Journals (Sweden)

    Jon Kjellin

    2013-01-01

    turbine has fixed pitch and is only controlled electrically accommodated by passive stall of the blades. By electrically controlling the generator rotational speed with the inverter, passive stall regulation is enabled. The first results on experimental verification of stall regulation in gusty wind speeds are presented. The experiments show that the control system can keep the turbine rotational speed constant even at very gusty winds. It is concluded that electrical control accommodated by passive stall is sufficient as control of the wind turbine even at high wind speeds and can substitute mechanical control such as blade pitch.

  13. High Penetrated Wind Farm Impacts on the Electricity Price

    DEFF Research Database (Denmark)

    Haji Bashi, Mazaher; Yousefi, G. R.; Bak, Claus Leth

    2016-01-01

    Energy trading policies, intermittency of wind farm output power, low marginal cost of the production, are the key factors that cause the wind farms to be effective on the electricity price. In this paper, the Danish electricity market is studied as a part of Nord Pool. Considering the completely...... fossil fuel free overview in Danish energy policies, and the currently great share of wind power (more than 100% for some hours) in supplying the load, it is an interesting benchmark for the future electricity markets. Negative prices, price spikes, and price volatility are considered as the main effects...... of the high penetrated wind farm integration into electricity markets. Then, stochastic programming approach is employed to compare the volume of trades for a typical wind farm in a high and low wind penetrated market. Although increasing price spikes and volatility was reported in the literature...

  14. Electric Generators and their Control for Large Wind Turbines

    DEFF Research Database (Denmark)

    Boldea, Ion; Tutelea, Lucian; Rallabandi, Vandana

    2017-01-01

    The electric generator and its power electronics interface for wind turbines (WTs) have evolved rapidly toward higher reliability and reduced cost of energy in the last 40 years. This chapter describes the up-to-date electric generators existing in the wind power industry, namely, the doubly fed...

  15. Equilibrium pricing in electricity markets with wind power

    Science.gov (United States)

    Rubin, Ofir David

    Estimates from the World Wind Energy Association assert that world total wind power installed capacity climbed from 18 Gigawatt (GW) to 152 GW from 2000 to 2009. Moreover, according to their predictions, by the end of 2010 global wind power capacity will reach 190 GW. Since electricity is a unique commodity, this remarkable expansion brings forward several key economic questions regarding the integration of significant amount of wind power capacity into deregulated electricity markets. The overall dissertation objective is to develop a comprehensive theoretical framework that enables the modeling of the performance and outcome of wind-integrated electricity markets. This is relevant because the state of knowledge of modeling electricity markets is insufficient for the purpose of wind power considerations. First, there is a need to decide about a consistent representation of deregulated electricity markets. Surprisingly, the related body of literature does not agree on the very economic basics of modeling electricity markets. That is important since we need to capture the fundamentals of electricity markets before we introduce wind power to our study. For example, the structure of the electric industry is a key. If market power is present, the integration of wind power has large consequences on welfare distribution. Since wind power uncertainty changes the dynamics of information it also impacts the ability to manipulate market prices. This is because the quantity supplied by wind energy is not a decision variable. Second, the intermittent spatial nature of wind over a geographical region is important because the market value of wind power capacity is derived from its statistical properties. Once integrated into the market, the distribution of wind will impact the price of electricity produced from conventional sources of energy. Third, although wind power forecasting has improved in recent years, at the time of trading short-term electricity forwards, forecasting

  16. Gas-fired wind power and electric hydrogen

    OpenAIRE

    Hemmes, K.

    2006-01-01

    In the seemingly endless discussions about the pros and cons of wind power even its advocates have to agree that though wind can fly, with offshore wind farms soon to become reality, this only exacerbates the problem of the winds changeability. Even now the major producers of electricity and power grid companies foresee grave difficulties from the peaks and dips in supply of this green power source. Dr Kas Hemmes of the faculty of Systems Engineering, Policy Analysis, and Management at TU Del...

  17. Does wind energy mitigate market power in deregulated electricity markets?

    International Nuclear Information System (INIS)

    Ben-Moshe, Ori; Rubin, Ofir D.

    2015-01-01

    A rich body of literature suggests that there is an inverse relationship between wind power penetration rate into the electricity market and electricity prices, but it is unclear whether these observations can be generalized. Therefore, in this paper we seek to analytically characterize market conditions that give rise to this inverse relationship. For this purpose, we expand a recently developed theoretical framework to facilitate flexibility in modeling the structure of the electric industry with respect to the degree of market concentration and diversification in the ownership of wind power capacity. The analytical results and their attendant numerical illustrations indicate that the introduction of wind energy into the market does not always depress electricity prices. Such a drop in electricity prices is likely to occur when the number of firms is large enough or the ownership of wind energy is sufficiently diversified, or most often a combination of the two. Importantly, our study defines the circumstances in which the question of which type of firm invests in wind power capacity is crucial for market prices. - Highlights: • Studies show that electricity prices decrease with increased wind power capacity. • We investigate market conditions that give rise to this inverse relationship. • Average prices for wind energy are systematically lower than average market prices. • Conventional generation firms may increase market power by investing in wind farms. • Energy policy should seek to diversify the ownership of wind power capacity

  18. Survey of wind power potential for wind-based electricity at ...

    African Journals Online (AJOL)

    The potential for wind-generated electricity is examined using 22 months wind data collected from a prospective site located in the southern highlands of Tanzania. While the data for the year 2001 was from March to December that of 2002 was for all the twelve months of the year. Characteristics of monthly and annual wind ...

  19. Bidirectional ionic wind in nonpremixed counterflow flames with DC electric fields

    KAUST Repository

    Park, Daegeun

    2016-05-05

    Under an electric field, ions in the reaction zone of a flame generate a bulk flow motion called ionic wind. Because the majority of ions are positive, ionic wind is commonly considered to be unidirectional toward the cathode. A more thorough understanding of the effects of electric fields on flames could be obtained by clarifying the role of minor negative ions in the ionic wind. Here, we report on the effects of direct current on nonpremixed counterflow flames by visualizing the ionic wind. We found that the original flow field separates near the flame when it locates at a flow stagnation plane, resulting in a double-stagnant flow configuration. This evidences a bidirectional ionic wind blowing from the flame to both the cathode and the anode due to the positive and the negative ions, respectively. Meanwhile, an electric body force pulls the flame toward the cathode. Thus, the electric field affects the strain rate and the axial location of the stoichiometry, which are important for characterizing nonpremixed counterflow flames. In addition, measurement of the electric current density roughly showed a nearly saturated current when these flames restabilized under relatively high voltage. Detailed explanations of flame behavior, electric currents, and flow characteristics of various fuels are discussed in this study.

  20. Wind energy status in renewable electrical energy production in Turkey

    International Nuclear Information System (INIS)

    Kaygusuz, Kamil

    2010-01-01

    Main electrical energy sources of Turkey are thermal and hydraulic. Most of the thermal sources are derived from natural gas. Turkey imports natural gas; therefore, decreasing usage of natural gas is very important for both economical and environmental aspects. Because of disadvantages of fossil fuels, renewable energy sources are getting importance for sustainable energy development and environmental protection. Among the renewable sources, Turkey has very high wind energy potential. The estimated wind power capacity of Turkey is about 83,000 MW while only 10,000 MW of it seems to be economically feasible to use. Start 2009, the total installed wind power capacity of Turkey was only 4.3% of its total economical wind power potential (433 MW). However, the strong development of wind energy in Turkey is expected to continue in the coming years. In this study, Turkey's installed electric power capacity, electric energy production is investigated and also Turkey current wind energy status is examined. (author)

  1. Present and prospective role of wind energy in electricity supply

    International Nuclear Information System (INIS)

    Sesto, E.; Ancona, D.F.

    1995-01-01

    Information is provided on world-wide wind energy applications for the production of electricity and the various factors driving the wind turbine market: technology improvements and cost reduction, national research, incentives, utility and public acceptance. Possible restraints to (noise, aesthetics) and benefits (especially in isolated systems) from wind plant integration in utility systems are considered, as well as the use of stand-alone wind systems. Some possible forecasts on the role of wind energy in the next two decades are also given. 4 refs., 2 figs., 1 tab

  2. Electrical system studies for the grid connection of wind farms

    International Nuclear Information System (INIS)

    Arp, K.; Hanson, J.; Hopp, S.; Zimmermann, W.

    2007-01-01

    Wind power is gaining momentum in the world's energy balance. Several issues have to be addressed whenever power-generating devices are connected to the grid. The paper describes studies needed to evaluate the influence of wind farms on the connected transmission system and how faults in the system impact on induction generators in a wind farm. Some generalized results of studies for an offshore wind farm in the North Sea and a Bulgarian wind farm show how studies can influence the layout of the internal network and the electrical equipment. (authors)

  3. Wind power and a liberalised North European electricity exchange

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, L.H.; Morthorst, P.E.; Skytte, K. [and others

    1999-03-01

    Conditions for wind power on a liberalised North European electrical power market are addressed in the paper. Results are presented from a recently completed study carried out by Risoe National Laboratory in collaboration with the Danish electric utilities Eltra, Elsam and Elkraft. A main result from the study is, that the market will be able to provide the necessary power regulation, that will be required year 2005 as consequence of the expected wind power capacity extension, according to the Danish energy plan, Energy21. The averege sales price on the market for the wind-generated electricity is less than the average spot market price, due to provision of power regulation to balance the unpredictability of the wind power. This reduction in the market value of wind power has been calculated to 10-20 DKK/MWh of 1.3-2.7 EUR/MWh. (au)

  4. Utilization of excess wind power in electric vehicles

    International Nuclear Information System (INIS)

    Hennings, Wilfried; Mischinger, Stefan; Linssen, Jochen

    2013-01-01

    This article describes the assessment of future wind power utilization for charging electric vehicles (EVs) in Germany. The potential wind power production in the model years 2020 and 2030 is derived by extrapolating onshore wind power generation and offshore wind speeds measured in 2007 and 2010 to the installed onshore and offshore wind turbine capacities assumed for 2020 and 2030. The energy consumption of an assumed fleet of 1 million EVs in 2020 and 6 million in 2030 is assessed using detailed models of electric vehicles, real world driving cycles and car usage. It is shown that a substantial part of the charging demand of EVs can be met by otherwise unused wind power, depending on the amount of conventional power required for stabilizing the grid. The utilization of wind power is limited by the charging demand of the cars and the bottlenecks in the transmission grid. -- Highlights: •Wind power available for charging depends on minimum required conventional power (must-run). •With 20 GW must-run power, 50% of charging can be met by excess wind power. •Grid bottlenecks decrease charging met by wind power from 50 % to 30 %. •With zero must-run power, only very little wind power is available for charging

  5. The General Electric MOD-1 wind turbine generator program

    Science.gov (United States)

    Poor, R. H.; Hobbs, R. B.

    1979-01-01

    The design, fabrication, installation and checkout of MOD-1, a megawatt class wind turbine generator which generates utility grade electrical power, is described. A MOD-1/MOD-1A tradeoff study is discussed.

  6. Wind turbine cost of electricity and capacity factor

    International Nuclear Information System (INIS)

    Cavallo, A.J.

    1995-01-01

    Wind turbines are currently designed to minimize the cost of electricity at the wind turbine (the busbar cost) in a given wind regime, ignoring constraints on the capacitor factor (the ratio of the average power output to the maximum power output). The trade-off between these two quantities can be examined in a straightforward fashion; it is found that the capacitor factor can be increased by a factor of 1.3 above its value at the cost minimum for a 10 percent increase in the cost of electricity. This has important implications for the large scale integration of wind electricity on utility grids where the cost of transmission and storage may be a significant fraction of the cost of delivered electricity. (Author)

  7. Centralized electricity generation in offshore wind farms using hydraulic networks

    NARCIS (Netherlands)

    Jarquin Laguna, A.

    2017-01-01

    The work presented in this thesis explores a new way of generation, collection and transmission of wind energy inside a wind farm, in which the electrical conversion does not occur during any intermediate conversion step before the energy has reached the offshore central platform. A centralized

  8. Assessment of wind energy potential for electricity generation

    African Journals Online (AJOL)

    fossil fuel for energy production has been estimated to contribute about 80. % of the total gses responsible for the green house effect of the atmosphere. Renewable energy sources such as wind, if thoroughly investigated, could be used to reduce the dependence on fossil fuels for electricity generation. Although wind ...

  9. Hybrid Test Bed of Wind Electric Generator with Photovoltaic Panels

    OpenAIRE

    G.D.Anbarasi Jebaselvi; S.Paramasivam

    2014-01-01

    Driven by the increasing costs of power production and decreasing fossil fuel reserves with the addition of global environmental concerns, renewable energy is now becoming significant fraction of total electricity production in the world. Advancements in the field of wind electric generator technology and power electronics help to achieve rapid progress in hybrid power system which mainly involves wind, solar and diesel energy with a good battery back-up. Here the discussion brings about the ...

  10. Electrical and non-electrical environment of wind turbine main components

    DEFF Research Database (Denmark)

    Holboell, J.; Henriksen, M.; Olsen, R.S.

    of application standards for wind turbine electrical equipment. Component-level environmental requirements as given in equipment-specific standards are compared with the environment described in the IEC's 61400 series concerning wind turbines. Based on methods defined in IEC 60721, the non-electrical environment...

  11. Wind power electric systems modeling, simulation and control

    CERN Document Server

    Rekioua, Djamila

    2014-01-01

    The book helps readers understand key concepts in standalone and grid connected wind energy systems and features analysis into the modeling and optimization of commonly used configurations through the implementation of different control strategies.Utilizing several electrical machinery control approaches, such as vector control and direct torque control 'Wind Power Electric Systems' equips readers with the means to understand, assess and develop their own wind energy systems and to evaluate the performance of such systems.Mathematical models are provided for each system and a corresponding MAT

  12. Fault Detection and Isolation for Wind Turbine Electric Pitch System

    DEFF Research Database (Denmark)

    Zhu, Jiangsheng; Ma, Kuichao; Hajizadeh, Amin

    2017-01-01

    This paper presents a model-based fault detection and isolation scheme applied on electric pitch system of wind turbines. Pitch system is one of the most critical components due to its effect on the operational safety and the dynamics of wind turbines. Faults in this system should be precisely...... detected to prevent failures and decrease downtime. To detect faults of electric pitch actuators and sensors, an extended kalman filter (EKF) based multiple model adaptive estimation (MMAE) designed to estimate the states of the system. The proposed method is demonstrated in case studies. The simulation...... results show that the proposed method detects different fault scenarios of wind turbines under the stochastic external condition....

  13. Market integration of wind power in electricity system balancing

    DEFF Research Database (Denmark)

    Sorknæs, Peter; Andersen, Anders N.; Tang, Jens

    2013-01-01

    In most countries markets for electricity are divided into wholesale markets on which electricity is traded before the operation hour, and real-time balancing markets to handle the deviations from the wholesale trading. So far, wind power has been sold only on the wholesale market and has been...... known to increase the need for balancing. This article analyses whether wind turbines in the future should participate in the balancing markets and thereby play a proactive role. The analysis is based on a real-life test of proactive participation of a wind farm in West Denmark. It is found...

  14. Electric vehicles and large-scale integration of wind power

    DEFF Research Database (Denmark)

    Liu, Wen; Hu, Weihao; Lund, Henrik

    2013-01-01

    was 6.5% in 2009 and which has the plan to develop large-scale wind power. The results show that electric vehicles (EVs) have the ability to balance the electricity demand and supply and to further the wind power integration. In the best case, the energy system with EV can increase wind power...... with this imbalance and to reduce its high dependence on oil production. For this reason, it is interesting to analyse the extent to which transport electrification can further the renewable energy integration. This paper quantifies this issue in Inner Mongolia, where the share of wind power in the electricity supply...... integration by 8%. The application of EVs benefits from saving both energy system cost and fuel cost. However, the negative consequences of decreasing energy system efficiency and increasing the CO2 emission should be noted when applying the hydrogen fuel cell vehicle (HFCV). The results also indicate...

  15. Private wind powered electricity generators for industry in the UK

    Science.gov (United States)

    Thabit, S. S.; Stark, J.

    This paper investigates the impact of the provisions of the new Energy Act, 1983 on industrial wind-powered private generators of electricity and the effects of published tariffs on various industrial working patterns. Up to 30 percent savings can be achieved in annual electricity bill costs for an industrial generator/user of electricity working a single daily shift, if located in a favorable, 7 m/s mean annual wind speed regime. Variation of the availability charge between Electricity Boards about a base value of 0.70 pounds sterling/kVA was found to have insignificant (+ or - 1.3 percent) impact on total electricity bill costs. It was also shown that for industrial users of electricity, the simpler two-rate purchase terms were commercially adequate when compared with the four-rate alternative where expensive metering becomes necessary.

  16. Electric Vehicles in Power Systems with 50% Wind Power Penetration

    DEFF Research Database (Denmark)

    Østergaard, Jacob; Foosnæs, Anders; Xu, Zhao

    2009-01-01

    will be an important balancing measure to enable the Danish government’s energy strategy, which implies 50% wind power penetration in the electric power system. An EV will be a storage device for smoothing power fluctuations from renewable resources especially wind power and provide valuable system services...... for a reliable power system operation. Cost-benefit analysis shows that intelligent bidirectional charging – vehicle to grid (V2G) – provides a socio-economic profit of 150 million Euro/year in the Danish electric power system in 2025 assuming that 15% of the Danish road transport need is supplied by electricity....... This paper analyse the potential for using EVs in Denmark and identify the benefits of the electric power system with high wind power generation by intelligent charging of the EVs. Based on the analysis important technology gabs are identified, and the corresponding research and development initiatives...

  17. International energy technology collaboration: wind power integration into electricity systems

    International Nuclear Information System (INIS)

    Justus, D.

    2006-01-01

    A rapid growth of wind power since the 1990s has led to notable market shares in some electricity markets. This growth is concentrated in a few countries with effective Research, Development and Demonstration (RD and D) programmes and with policies that support its diffusion into the market place. The speed and depth of its penetration in these electricity markets have amplified the need to address grid integration concerns, so as not to impede the further penetration of wind power. Research on technologies, tools and practices for integrating large amounts of wind power into electricity supply systems is attempting to respond to this need. In recent years, existing international collaborative research efforts have expanded their focus to include grid integration of wind power and new consortia have been formed to pool knowledge and resources. Effective results benefit a few countries that already have a significant amount of wind in their electricity supply fuel mix, as well as to the potential large markets worldwide. This paper focuses on the challenge of bringing significant amounts of intermittent generating sources into grids dominated by large central generating units. It provides a brief overview of the growth of wind power, mainly since 1990, the technical and operational issues related to integration and selected collaborative programmes underway to address grid integration concerns. (author)

  18. Wind energy in the electric power system

    DEFF Research Database (Denmark)

    Polinder, H.; Peinke, J.; Kramer, O.

    2016-01-01

    have to behave when connected to the power system. In this way, they already incorporate basic ancillary services. However, frequency control is normally not provided as a regular reserve, because this would require reserving parts of the available wind capacity as stand-by capacity. Within R......The ongoing increase in renewable power generation causes a parallel overall decrease in conventional power generation from, in particular, fossil and nuclear power plants. Apart from providing market-based active power schedules, these power plants are crucial for offering ancillary services...... in order to guarantee a reliable stable power supply at any instant in time. Substituting these plants with renewable generation units requires the latter to be capable of providing these ancillary services. The state of the art is that grid codes are used to define the way wind turbines and wind farms...

  19. Energy efficient motion control of the electric bus on route

    Science.gov (United States)

    Kotiev, G. O.; Butarovich, D. O.; Kositsyn, B. B.

    2018-02-01

    At present, the urgent problem is the reduction of energy costs of urban motor transport. The article proposes a method of solving this problem by developing an energy-efficient law governing the movement of an electric bus along a city route. To solve this problem, an algorithm is developed based on the dynamic programming method. The proposed method allows you to take into account the constraints imposed on the phase coordinates, control action, as well as on the time of the route. In the course of solving the problem, the model of rectilinear motion of an electric bus on a horizontal reference surface is considered, taking into account the assumptions that allow it to be adapted for the implementation of the method. For the formation of a control action in the equations of motion dynamics, an algorithm for changing the traction / braking torque on the wheels of an electric bus is considered, depending on the magnitude of the control parameter and the speed of motion. An optimal phase trajectory was obtained on a selected section of the road for the prototype of an electric bus. The article presents the comparison of simulation results obtained with the optimal energy efficient control law with the results obtained by a test driver. The comparison proved feasibility of the energy efficient control law for the automobile city electric transport.

  20. Towards 50% wind electricity in Denmark: Dilemmas and challenges

    Science.gov (United States)

    Bach, Paul-Frederik

    2016-05-01

    Electricity and heat supply systems are essential contributors to a fossil-free future in Denmark. The combined production of heat and power (CHP) and the production of wind energy are already well developed in Denmark. Combined heat and power covers about 40% of the demand for space heating in Denmark, and the production of wind energy is supposed to exceed 50% of the demand for electricity by 2020. The changing electricity and heat production has some consequences already now: i) Decreasing wholesale prices in Denmark and in other countries. ii) Thermal power plants are closing down. Denmark is no longer self-sufficient with electricity under all conditions. iii) The electricity production pattern does not match the demand pattern. The result is that the neighbouring countries must absorb the variations from wind and solar power. Essential challenges: i) The future of combined heat and power in Denmark is uncertain. ii) Denmark will need new backup capacity for filling the gaps in wind power and solar cell output. iii) Flexible electricity consumers are supposed to contribute to balancing the future power systems. There is still a long way to go before the Smart Grid visions are implemented in large scale. iv) The transformation of the power system will create new risks of power failures.

  1. Universal features of particle motion in ac electric fields

    Science.gov (United States)

    Niemeyer, L.; Seeger, M.

    2015-11-01

    Mobile particles present as contaminants in high voltage gas insulated switchgear (GIS) may constitute a risk for insulation failure. The understanding of their motion in the electric field of the insulation gap is therefore essential for quality control in manufacturing, commissioning and in service monitoring. Published research on particle motion in ac electric fields has shown that this rather complex process depends on numerous parameters, many of which remain unknown under practical conditions. This renders modelling, generalization of experimental data and practical application difficult. The scope of this paper therefore is to develop a unified description of particle motion which minimizes the number of controlling parameters, enables the comparison of experimental data and allows simple interpretation relations to be derived. This is achieved by making the controlling equations dimensionless with an appropriate choice of reference values and by using simplifying assumptions for the specific conditions prevailing in GIS. The resulting generalized description of the process can then be summarized in the form of 2D patterns (dynamic maps). Approximate scaling relations are derived between specific features of these patterns and particle-related parameters. A reference case is discussed in detail. The non-linear character of the equation of motion suggests that the particle motion may be a deterministic process with chaotic features. This is confirmed by a preliminary chaos-theoretical analysis of the process.

  2. Contribution of wind energy to future electricity requirements of Pakistan

    International Nuclear Information System (INIS)

    Harijan, K.; Uqaili, M. A.; Memon, M.

    2007-01-01

    Pakistan is an energy deficit country. About half of the country's population has no access to electricity and per capita supply is only 520 kWh. About 67% of the conventional electricity is generated from fossil fuels with 51% and 16% share of gas and oil respectively. It has been projected that electricity demand in Pakistan would increase at an average annual growth rate of 5% to 12% under different scenarios. The indigenous reserves of oil and gas are limited and the country heavily depends on imported oil. The oil import bill is a serious strain on the country's economy and has been deteriorating the balance of payment situation. Pakistan is becoming increasingly more dependent on a few sources of supply and its energy security often hangs on the fragile threat of imported oil that is subject to supply disruptions and price volatility. The production and consumption of fossil fuels also adversely affects the quality of the environment due to indiscriminate release of toxic substances. Pakistan spends huge amount on the degradation of the environment. This shows that Pakistan must develop alternate, indigenous and environment friendly energy resources such as wind energy to meet its future electricity requirements. This paper presents an overview of wind power generation potential and assessment of its contribution to future electricity requirements of Pakistan under different policy scenarios. The country has about 1050 km long coastline. The technical potential of centralized grid connected wind power and wind home systems in the coastal area of the country has been estimated as about 484 TWh and 0.135 TWh per year respectively. The study concludes that wind power could meet about 20% to 50% of the electricity demand in Pakistan by the year 2030. The development and utilization of wind power would reduce the pressure on oil imports, protect the environment from pollution and improve the socio-economic conditions of the people

  3. Wind energy in a competitive electricity supply environment

    Energy Technology Data Exchange (ETDEWEB)

    Strbac, G.; Jenkins, N. [Manchester Centre for Electrical Energy, Manchester (United Kingdom)

    1995-12-31

    In the UK, there has been an increasing interest in the commercial aspects of the impact of wind energy on transmission and distribution networks. In a competitive electricity supply environment, mechanisms for pricing network services are considered to be the main vehicle for evaluating that impact. This article reviews the major pricing strategies based on embedded costs, short and long run marginal costing theory as well as time-of-use pricing, and comments on the influence of each particular strategy on the calculated value of wind energy. Also, prospective tools for evaluating savings in capital and operating network costs due to wind generation, are identified. (author)

  4. Electrical components library for HAWC2; Wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    Cutululis, N.A.; Larsen, Torben J.; Soerensen, Poul; Hansen, Anca D. (Risoe National Lab., DTU, Wind Energy Dept., Roskilde (DK)); Iov, F. (Aalborg Univ., Institute of Energy Technology (DK))

    2007-12-15

    The work presented in this report is part of the EFP project called ''A Simulation Platform to Model, Optimize and Design Wind Turbines'' partly funded by the Danish Energy Authority under contract number 1363/04-0008. The project is carried out in cooperation between Risoe National Laboratory and Aalborg University. In this project, the focus is on the development of a simulation platform for wind turbine systems using different simulation tools. This report presents the electric component library developed for use in the aeroelastic code HAWC2. The developed library includes both steady state and dynamical models for fixed and variable speed wind turbines. A simple steady-state slip model was developed for the fixed speed wind turbine. This model is suitable for aeroelastic design of wind turbines under normal operation. A dynamic model of an induction generator for the fixed speed wind turbine was developed. The model includes the dynamics of the rotor fluxes. The model is suitable for a more detailed investigation of the mechanical-electrical interaction, both under normal and fault operation. For the variable speed wind turbine, a steadystate model, typically used in aeroelastic design, was implemented. The model can be used for normal and, to some extent, for fault operation. The reduced order dynamic model of a DFIG was implemented. The model includes only the active power controller and can be used for normal operation conditions. (au)

  5. The Relationship Between Electricity Price and Wind Power Generation in Danish Electricity Markets

    DEFF Research Database (Denmark)

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2010-01-01

    of competitive electricity markets in some ways, is chosen as the studied power system. The relationship between the electricity price (both the spot price and the regulation price) and the wind power generation in an electricity market is investigated in this paper. The spot price, the down regulation price...... and the up regulation price generally decreases when the wind power penetration in the power system increases. The statistical characteristics of the spot price for different wind power penetration are analyzed. The findings of this paper may be useful for wind power generation companies to make the optimal...... bidding strategy and may be also useful for the optimal operation of modern power systems with high wind power penetrations....

  6. Electric potential of the moon in the solar wind.

    Science.gov (United States)

    Freeman, J. W., Jr.; Fenner, M. A.; Hills, H. K.

    1973-01-01

    Acceleration and detection of the lunar thermal ionosphere in the presence of the lunar electric field yields a value of at least +10 V for the lunar electric potential for solar zenith angles between approximately 20 and 45 deg and in the magnetosheath or solar wind. An enhanced positive ion flux is observed with the Apollo Lunar Surface Experiments Package Suprathermal Ion Detector Experiment when a preacceleration voltage attains certain values. This enhancement is greater when the moon is in the solar wind as opposed to the magnetosheath.

  7. Electricity generating system. [Wind/diesel/flywheel system

    Energy Technology Data Exchange (ETDEWEB)

    Moody, R.L.

    1992-02-05

    An electricity generating system is described which includes a water tank with electric heating elements connected to the water cooling system of a diesel engine which is heated by excess output of the system. Power in excess of that required by a load which is generated by a wind turbine driven generator runs up a flywheel and further excess is absorbed in the tank. A fan associated with a radiator connected to the tank may be operated to dissipate further excess power. When the load requirements exceed the output of the generators linked to the wind turbine and the flywheel the engine operates a synchronous alternator. (author).

  8. The Effect of Wind Power on Electricity Prices in Denmark

    DEFF Research Database (Denmark)

    Jonsson, Tryggvi; Madsen, Henrik

    This report is the result of a special course taken by the author at IMM DTU under the guidance of professor Henrik Madsen. The aim of the project is to analyze the influence wind energy has on the electricity spot price in Western Denmark and investigate how information about wind power production...... can be used to model the electricity spot price. Various model types were tried, giving very different performance. Here, only the models that performed best are discussed in order to keep focus on the projects goal....

  9. Optimal contracts for wind power producers in electricity markets

    KAUST Repository

    Bitar, E.

    2010-12-01

    This paper is focused on optimal contracts for an independent wind power producer in conventional electricity markets. Starting with a simple model of the uncertainty in the production of power from a wind turbine farm and a model for the electric energy market, we derive analytical expressions for optimal contract size and corresponding expected optimal profit. We also address problems involving overproduction penalties, cost of reserves, and utility of additional sensor information. We obtain analytical expressions for marginal profits from investing in local generation and energy storage. ©2010 IEEE.

  10. LCA of electricity systems with high wind power penetration

    DEFF Research Database (Denmark)

    Turconi, Roberto; O' Dwyer, C. O.; Flynn, D.

    capacity, and decreased with the addition of storage. However, a consequence of adding storage was the increased use of base load coal power plants, ultimately leading to an increase in total emissions from the Irish electricity system. Consequently, the present study indicates that while investing in new......Electricity systems are shifting from being based on fossil fuels towards renewable sources to enhance energy security and mitigate climate change. However, by introducing high shares of variable renewables - such as wind and solar - dispatchable power plants are required to vary their output...... to fulfill the remaining electrical demand, potentially increasing their environmental impacts [1,2]. In this study the environmental impacts of potential short-term future electricity systems in Ireland with high shares of wind power (35-50% of total installed capacity) were evaluated using life cycle...

  11. The electric potential of the moon in the solar wind

    Science.gov (United States)

    Freeman, J. W., Jr.; Fenner, M. A.; Hills, H. K.

    1973-01-01

    Acceleration and detection of the lunar thermal ionosphere in the presence of the lunar electric field yields a value of approximately +10 V for the lunar electric potential for solar zenith angles between 20 and 45 deg and in the magnetosheath or solar wind. The ion number density of the thermal ionosphere observed is compatible with a surface neutral number density of about 100,000 atoms/cu cm.

  12. Global changes in total and wind electricity (1990–2014

    Directory of Open Access Journals (Sweden)

    María del P. Pablo-Romero

    2017-03-01

    Full Text Available Wind energy is one of the renewable energies which have less adverse environmental impact and is becoming economically affordable long before several other renewable energies. Over recent years, substantial additions have been noted in wind energy capacity, although many differences can be observed between countries. Using the latest available data, this paper provides a concise analysis of wind energy and electricity consumption trends for the period 1990–2014 in a dual perspective, by principal world regions and by per capita gross national income levels in 2014. Electricity consumption has been divided into three types of energy: non-renewable, renewable excluding wind and wind energy. Annual rates of change, energy intensity, energy in per capita terms and some ratios have been analyzed. Notable regional differences and trends are observed in the studied variables. The first 15 European Union countries, other developed countries (ODC and East Asian (EAS and South Asian countries (SAS are the regions which currently have the highest wind capacity.

  13. Electricity for Road Transport, Flexible Power Systems and Wind Power

    DEFF Research Database (Denmark)

    Nielsen, Lars Henrik; Ravn, Hans; Meibom, Peter

    (transmission and distribution) as consequence of increasing electricity demand, and new flexible consumption patterns from segments in the transport sector, and as consequence of increasing capacity on wind power in the system. 6: Setting up and analysis of combined scenarios covering both the heat and power......The aim of the project is to analyse the potential synergistic interplay that may arise between the power sector and the transport sector, if parts of the road transport energy needs are based on electricity via the utilisation of plug-in hybrid electric vehicles and pure electric vehicles......-vehicle connection systems including technical regulation options and analysis of needs for standardisation. 4: Setting up scenarios covering potential developments for utilizing electric drive trains in road transport. Period: Up to year 2030. 5: Analysis of capacity constraints in the electricity grid...

  14. Integration of electric drive vehicles in the Danish electricity network with high wind power penetration

    DEFF Research Database (Denmark)

    Chandrashekhara, Divya K; Østergaard, Jacob; Larsen, Esben

    2010-01-01

    /conventional) which are likely to fuel these cars. The study was carried out considering the Danish electricity network state around 2025, when the EDV penetration levels would be significant enough to have an impact on the power system. Some of the interesting findings of this study are - EDV have the potential......This paper presents the results of a study carried out to examine the feasibility of integrating electric drive vehicles (EDV) in the Danish electricity network which is characterised by high wind power penetration. One of the main aims of this study was to examine the effect of electric drive...... vehicles on the Danish electricity network, wind power penetration and electricity market. In particular the study examined the effect of electric drive vehicles on the generation capacity constraints, load curve, cross border transmission capacity and the type of generating sources (renewable...

  15. Transmission and wind investment in a deregulated electricity industry

    DEFF Research Database (Denmark)

    Maurovich-Horvat, Lajos; Boomsma, Trine Krogh; Fleten, Stein-Erik

    2013-01-01

    carrying out investment in wind farms. In this paper, we analyse the interaction between the two conflicting objectives under various assumptions about the electricity market structure and the degree of producers' market power. Via a three-node illustrative example, we show that a merchant investor......The transition to a more sustainable energy system requires investment in renewable energy technologies such as wind. Due to the dispersed nature of sites for wind farms, concomitant expansion of the transmission network is also necessary. While the two objectives could be reconciled within...... the auspices of a regulated welfare-maximising planner, recent restructuring of electricity industries has introduced a merchant model for transmission investment, which provides congestion rents from construction of a new line. Thus, the merchant investor's incentives are different from those of producers...

  16. Transmission and wind investment in a deregulated electricity industry

    DEFF Research Database (Denmark)

    Maurovich-Horvat, Lajos; Boomsma, Trine Krogh; Siddiqui, Afzal S.

    2015-01-01

    Adoption of dispersed renewable energy technologies requires transmission network expansion. Besides the transmission system operator (TSO), restructuring of electricity industries has introduced a merchant investor (MI), who earns congestion rents from constructing new lines. We compare these tw...... proportion of energy is produced by wind. In effect, withholding of generation capacity by producers prompts more transmission investment since the TSO aims to increase welfare by subsidizing wind and the MI creates more flow to maximize profit.......Adoption of dispersed renewable energy technologies requires transmission network expansion. Besides the transmission system operator (TSO), restructuring of electricity industries has introduced a merchant investor (MI), who earns congestion rents from constructing new lines. We compare these two...... market designs via a stochastic bi-level programming model that has either the MI or the TSO making transmission investment decisions at the upper level and power producers determining generation investment and operation at the lower level while facing wind power variability. We find that social welfare...

  17. Wind power impacts and electricity storage - a time scale perspective

    DEFF Research Database (Denmark)

    Hedegaard, Karsten; Meibom, Peter

    2012-01-01

    technologies – batteries, flow batteries, compressed air energy storage, electrolysis combined with fuel cells, and electric vehicles – are moreover categorised with respect to the time scales at which they are suited to support wind power integration. While all of these technologies are assessed suitable...

  18. Influence of offshore wind farms layout on electrical resonances

    DEFF Research Database (Denmark)

    Holdyk, Andrzej; Holbøll, Joachim; Koldby, Erik

    2014-01-01

    cause resonances between cables and transformers, which might lead to potentially harmful overvoltages / currents. This paper shows how the topology of the collection grid of offshore wind farms influences the occurrence of electrical resonances in medium- and high-frequency region. Broad band models...

  19. Optimization of electrical parameters of windings used in axial flux electrical machines

    International Nuclear Information System (INIS)

    Uhrik, M.

    2012-01-01

    This paper deals with shape optimization of windings used in electrical machines with disc type construction. These machines have short axial length what makes them suitable for use in small wind-power turbines or in-wheel traction drives. Disc type construction of stator offers more possibilities for winding arrangements than are available in classical machines with cylindrical construction. To find out the best winding arrangement for the novel disc type machine construction a series of analytical calculations, simulations and experimental measurements were performed. (Authors)

  20. Sharing wind power forecasts in electricity markets: A numerical analysis

    International Nuclear Information System (INIS)

    Exizidis, Lazaros; Kazempour, S. Jalal; Pinson, Pierre; Greve, Zacharie de; Vallée, François

    2016-01-01

    Highlights: • Information sharing among different agents can be beneficial for electricity markets. • System cost decreases by sharing wind power forecasts between different agents. • Market power of wind producer may increase by sharing forecasts with market operator. • Extensive out-of-sample analysis is employed to draw reliable conclusions. - Abstract: In an electricity pool with significant share of wind power, all generators including conventional and wind power units are generally scheduled in a day-ahead market based on wind power forecasts. Then, a real-time market is cleared given the updated wind power forecast and fixed day-ahead decisions to adjust power imbalances. This sequential market-clearing process may cope with serious operational challenges such as severe power shortage in real-time due to erroneous wind power forecasts in day-ahead market. To overcome such situations, several solutions can be considered such as adding flexible resources to the system. In this paper, we address another potential solution based on information sharing in which market players share their own wind power forecasts with others in day-ahead market. This solution may improve the functioning of sequential market-clearing process through making more informed day-ahead schedules, which reduces the need for balancing resources in real-time operation. This paper numerically evaluates the potential value of sharing forecasts for the whole system in terms of system cost reduction. Besides, its impact on each market player’s profit is analyzed. The framework of this study is based on a stochastic two-stage market setup and complementarity modeling, which allows us to gain further insights into information sharing impacts.

  1. Computational Fluid Dynamic Analysis of a Floating Offshore Wind Turbine Experiencing Platform Pitching Motion

    Directory of Open Access Journals (Sweden)

    Thanhtoan Tran

    2014-08-01

    Full Text Available The objective of this study is to illustrate the unsteady aerodynamic effects of a floating offshore wind turbine experiencing the prescribed pitching motion of a supporting floating platform as a sine function. The three-dimensional, unsteady Reynolds Averaged Navier-Stokes equations with the shear-stress transport (SST k-ω turbulence model were applied. Moreover, an overset grid approach was used to model the rigid body motion of a wind turbine blade. The current simulation results are compared to various approaches from previous studies. The unsteady aerodynamic loads of the blade were demonstrated to change drastically with respect to the frequency and amplitude of platform motion.

  2. Optimal Wind Energy Integration in Large-Scale Electric Grids

    Science.gov (United States)

    Albaijat, Mohammad H.

    The major concern in electric grid operation is operating under the most economical and reliable fashion to ensure affordability and continuity of electricity supply. This dissertation investigates the effects of such challenges, which affect electric grid reliability and economic operations. These challenges are: 1. Congestion of transmission lines, 2. Transmission lines expansion, 3. Large-scale wind energy integration, and 4. Phaser Measurement Units (PMUs) optimal placement for highest electric grid observability. Performing congestion analysis aids in evaluating the required increase of transmission line capacity in electric grids. However, it is necessary to evaluate expansion of transmission line capacity on methods to ensure optimal electric grid operation. Therefore, the expansion of transmission line capacity must enable grid operators to provide low-cost electricity while maintaining reliable operation of the electric grid. Because congestion affects the reliability of delivering power and increases its cost, the congestion analysis in electric grid networks is an important subject. Consequently, next-generation electric grids require novel methodologies for studying and managing congestion in electric grids. We suggest a novel method of long-term congestion management in large-scale electric grids. Owing to the complication and size of transmission line systems and the competitive nature of current grid operation, it is important for electric grid operators to determine how many transmission lines capacity to add. Traditional questions requiring answers are "Where" to add, "How much of transmission line capacity" to add, and "Which voltage level". Because of electric grid deregulation, transmission lines expansion is more complicated as it is now open to investors, whose main interest is to generate revenue, to build new transmission lines. Adding a new transmission capacity will help the system to relieve the transmission system congestion, create

  3. Systems and methods for an integrated electrical sub-system powered by wind energy

    Science.gov (United States)

    Liu, Yan [Ballston Lake, NY; Garces, Luis Jose [Niskayuna, NY

    2008-06-24

    Various embodiments relate to systems and methods related to an integrated electrically-powered sub-system and wind power system including a wind power source, an electrically-powered sub-system coupled to and at least partially powered by the wind power source, the electrically-powered sub-system being coupled to the wind power source through power converters, and a supervisory controller coupled to the wind power source and the electrically-powered sub-system to monitor and manage the integrated electrically-powered sub-system and wind power system.

  4. Wind energy and electricity prices. Exploring the 'merit order effect'

    International Nuclear Information System (INIS)

    Morthost, P.E.; Ray, S.; Munksgaard, J.; Sinner, A.F.

    2010-04-01

    This report focuses on the effect of wind energy on the electricity price in the power market. As the report will discuss, adding wind into the power mix has a significant influence on the resulting price of electricity, the so called merit order effect (MOE). The merit order effect has been quantified and discussed in many scientific publications. This report ends the first phase of a study on the MOE, evaluating the impact of EWEA's 2020 scenarios on future European electricity prices. The basic principles of the merit order effect are provided in the first part of the document. The literature review itself contains methods and tools not only to quantify the merit order effect but also in order to forecast its future range and volume.

  5. The Electrostatic Wind Energy Converter : Electrical performance of a high voltage prototype

    NARCIS (Netherlands)

    Djairam, D.

    2008-01-01

    Wind energy is converted to electrical energy by letting the wind move charged particles against the direction of an electric field. The advantage of this type of conversion is that no rotational movement, which occurs in conventional wind turbines, is required. An electrostatic wind energy

  6. Exploration of dispatch model integrating wind generators and electric vehicles

    International Nuclear Information System (INIS)

    Haque, A.N.M.M.; Ibn Saif, A.U.N.; Nguyen, P.H.; Torbaghan, S.S.

    2016-01-01

    Highlights: • A novel business model for the BRPs is analyzed. • Imbalance cost of wind generation is considered in the UC-ED model. • Smart charging of EVs is included into the UC-ED problem to mitigate the imbalance cost. • Effects of smart charging on generation cost, CO 2 emissions and total network load are assessed. - Abstract: In recent years, the share of renewable energy sources (RES) in the electricity generation mix has been expanding rapidly. However, limited predictability of the RES poses challenges for traditional scheduling and dispatching mechanisms based on unit commitment (UC) and economic dispatch (ED). This paper presents an advanced UC-ED model to incorporate wind generators as RES-based units alongside conventional centralized generators. In the proposed UC-ED model, an imbalance cost is introduced reflecting the wind generation uncertainty along with the marginal generation cost. The proposed UC-ED model aims to utilize the flexibility of fleets of plug-in electric vehicles (PEVs) to optimally compensate for the wind generation uncertainty. A case study with 15 conventional units and 3 wind farms along with a fixed-sized PEV fleet demonstrates that shifting of PEV fleets charging at times of high wind availability realizes generation cost savings. Nevertheless, the operational cost saving incurred by controlled charging appears to diminish when dispatched wind energy becomes considerably larger than the charging energy of PEV fleets. Further analysis of the results reveals that the effectiveness of PEV control strategy in terms of CO 2 emission reduction is strongly coupled with generation mix and the proposed control strategy is favored in cases where less pollutant-based plants like nuclear and hydro power are profoundly dominant.

  7. Electric power from offshore wind via synoptic-scale interconnection.

    Science.gov (United States)

    Kempton, Willett; Pimenta, Felipe M; Veron, Dana E; Colle, Brian A

    2010-04-20

    World wind power resources are abundant, but their utilization could be limited because wind fluctuates rather than providing steady power. We hypothesize that wind power output could be stabilized if wind generators were located in a meteorologically designed configuration and electrically connected. Based on 5 yr of wind data from 11 meteorological stations, distributed over a 2,500 km extent along the U.S. East Coast, power output for each hour at each site is calculated. Each individual wind power generation site exhibits the expected power ups and downs. But when we simulate a power line connecting them, called here the Atlantic Transmission Grid, the output from the entire set of generators rarely reaches either low or full power, and power changes slowly. Notably, during the 5-yr study period, the amount of power shifted up and down but never stopped. This finding is explained by examining in detail the high and low output periods, using reanalysis data to show the weather phenomena responsible for steady production and for the occasional periods of low power. We conclude with suggested institutions appropriate to create and manage the power system analyzed here.

  8. Optimal Wind Power Uncertainty Intervals for Electricity Market Operation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ying; Zhou, Zhi; Botterud, Audun; Zhang, Kaifeng

    2018-01-01

    It is important to select an appropriate uncertainty level of the wind power forecast for power system scheduling and electricity market operation. Traditional methods hedge against a predefined level of wind power uncertainty, such as a specific confidence interval or uncertainty set, which leaves the questions of how to best select the appropriate uncertainty levels. To bridge this gap, this paper proposes a model to optimize the forecast uncertainty intervals of wind power for power system scheduling problems, with the aim of achieving the best trade-off between economics and reliability. Then we reformulate and linearize the models into a mixed integer linear programming (MILP) without strong assumptions on the shape of the probability distribution. In order to invest the impacts on cost, reliability, and prices in a electricity market, we apply the proposed model on a twosettlement electricity market based on a six-bus test system and on a power system representing the U.S. state of Illinois. The results show that the proposed method can not only help to balance the economics and reliability of the power system scheduling, but also help to stabilize the energy prices in electricity market operation.

  9. Electricity for road transport, flexible power systems and wind power

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, Lars Henrik; Ravn, H.; Meibom, P. (and others)

    2011-12-15

    The aim of the project is to analyse the potential synergistic interplay that may arise between the power sector and the transport sector, if parts of the road transport energy needs are based on electricity via the utilisation of plug-in hybrid electric vehicles and pure electric vehicles. The project focuses on the technical elements in the chain that comprises: 1: The electric vehicle status, potentials and expected development. Electric batteries are in focus in this part of the analysis. 2: Analysis of plug-in hybrid electric vehicle interacting with a local grid. 3: Analysis of grid-vehicle connection systems including technical regulation options and analysis of needs for standardisation. 4: Setting up scenarios covering potential developments for utilizing electric drive trains in road transport. Period: Up to year 2030. 5: Analysis of capacity constraints in the electricity grid (transmission and distribution) as consequence of increasing electricity demand, and new flexible consumption patterns from segments in the transport sector, and as consequence of increasing capacity on wind power in the system. 6: Setting up and analysis of combined scenarios covering both the heat and power system and the transport sector. (Author)

  10. A Quantitative Analysis of the Impact of Wind Energy Penetration on Electricity Prices in Ireland

    OpenAIRE

    O'Flaherty, Micheál; Riordan, Niall; O'Neill, Noel; Ahern, Ciara

    2014-01-01

    The maturity of wind technology combined with availability of suitable sites means Ireland is on course to generate 40% of its electricity from the wind by 2020.This work sets out to quantify, to what degree, if any, increased wind penetration translates into reduced wholesale and retail prices for electricity. The consensus from the literature is that increasing wind penetration reduces wholesale electricity prices, but views vary as to what degree this translates into reduced retail prices ...

  11. On the motion of dayside auroras caused by a solar wind pressure pulse

    Directory of Open Access Journals (Sweden)

    A. Kozlovsky

    2005-02-01

    Full Text Available Global ultraviolet auroral images from the IMAGE satellite were used to investigate the dynamics of the dayside auroral oval responding to a sudden impulse (SI in the solar wind pressure. At the same time, the TV all-sky camera and the EISCAT radar on Svalbard (in the pre-noon sector allowed for detailed investigation of the auroral forms and the ionospheric plasma flow. After the SI, new discrete auroral forms appeared in the poleward part of the auroral oval so that the middle of the dayside oval moved poleward from about 70° to about 73° of the AACGM latitude. This poleward shift first occurred in the 15 MLT sector, then similar shifts were observed in the MLT sectors located more westerly, and eventually the shift was seen in the 6 MLT sector. Thus, the auroral disturbance "propagated" westward (from 15 MLT to 6 MLT at an apparent speed of the order of 7km/s. This motion of the middle of the auroral oval was caused by the redistribution of the luminosity within the oval and was not associated with the corresponding motion of the poleward boundary of the oval. The SI was followed by an increase in the northward plasma convection velocity. Individual auroral forms showed poleward progressions with velocities close to the velocity of the northward plasma convection. The observations indicate firstly a pressure disturbance propagation through the magnetosphere at a velocity of the order of 200km/s which is essentially slower than the velocity of the fast Alfvén (magnetosonic wave, and secondly a potential (curl-free electric field generation behind the front of the propagating disturbance, causing the motion of the auroras. We suggest a physical explanation for the slow propagation of the disturbance through the magnetosphere and a model for the electric field generation. Predictions of the model are supported by the global convection maps produced by the SuperDARN HF radars. Finally, the interchange instability and the eigenmode toroidal

  12. Effects of Temporal Wind Patterns on the Value of Wind-Generated Electricity in California and the Northwest

    Energy Technology Data Exchange (ETDEWEB)

    Wiser, Ryan H; Wiser, Ryan H; Fripp, Matthias

    2008-05-01

    Wind power production is variable, but also has diurnal and seasonal patterns. These patterns differ between sites, potentially making electric power from some wind sites more valuable for meeting customer loads or selling in wholesale power markets. This paper investigates whether the timing of wind significantly affects the value of electricity from sites in California and the Northwestern United States. We use both measured and modeled wind data and estimate the time-varying value of wind power with both financial and load-based metrics. We find that the potential difference in wholesale market value between better-correlated and poorly correlated wind sites is modest, on the order of 5-10 percent. A load-based metric, power production during the top 10 percent of peak load hours, varies more strongly between sites, suggesting that the capacity value of different wind projects could vary by as much as 50 percent based on the timing of wind alone.

  13. Wind power electricity: the bigger the turbine, the greener the electricity?

    Science.gov (United States)

    Caduff, Marloes; Huijbregts, Mark A J; Althaus, Hans-Joerg; Koehler, Annette; Hellweg, Stefanie

    2012-05-01

    Wind energy is a fast-growing and promising renewable energy source. The investment costs of wind turbines have decreased over the years, making wind energy economically competitive to conventionally produced electricity. Size scaling in the form of a power law, experience curves and progress rates are used to estimate the cost development of ever-larger turbines. In life cycle assessment, scaling and progress rates are seldom applied to estimate the environmental impacts of wind energy. This study quantifies whether the trend toward larger turbines affects the environmental profile of the generated electricity. Previously published life cycle inventories were combined with an engineering-based scaling approach as well as European wind power statistics. The results showed that the larger the turbine is, the greener the electricity becomes. This effect was caused by pure size effects of the turbine (micro level) as well as learning and experience with the technology over time (macro level). The environmental progress rate was 86%, indicating that for every cumulative production doubling, the global warming potential per kWh was reduced by 14%. The parameters, hub height and rotor diameter were identified as Environmental Key Performance Indicators that can be used to estimate the environmental impacts for a generic turbine. © 2012 American Chemical Society

  14. Wind Power Electricity: The Bigger the Turbine, The Greener the Electricity?

    Science.gov (United States)

    2012-01-01

    Wind energy is a fast-growing and promising renewable energy source. The investment costs of wind turbines have decreased over the years, making wind energy economically competitive to conventionally produced electricity. Size scaling in the form of a power law, experience curves and progress rates are used to estimate the cost development of ever-larger turbines. In life cycle assessment, scaling and progress rates are seldom applied to estimate the environmental impacts of wind energy. This study quantifies whether the trend toward larger turbines affects the environmental profile of the generated electricity. Previously published life cycle inventories were combined with an engineering-based scaling approach as well as European wind power statistics. The results showed that the larger the turbine is, the greener the electricity becomes. This effect was caused by pure size effects of the turbine (micro level) as well as learning and experience with the technology over time (macro level). The environmental progress rate was 86%, indicating that for every cumulative production doubling, the global warming potential per kWh was reduced by 14%. The parameters, hub height and rotor diameter were identified as Environmental Key Performance Indicators that can be used to estimate the environmental impacts for a generic turbine. PMID:22475003

  15. The Value of Wind Technology Innovation: Implications for the U.S. Power System, Wind Industry, Electricity Consumers, and Environment

    Energy Technology Data Exchange (ETDEWEB)

    Mai, Trieu T [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lantz, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Mowers, Matthew [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wiser, Ryan [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-21

    Improvements to wind technologies have, in part, led to substantial deployment of U.S. wind power in recent years. The degree to which technology innovation will continue is highly uncertain adding to uncertainties in future wind deployment. We apply electric sector modeling to estimate the potential wind deployment opportunities across a range of technology advancement projections. The suite of projections considered span a wide range of possible cost and technology innovation trajectories, including those from a recent expert elicitation of wind energy experts, a projection based on the broader literature, and one reflecting estimates based on a U.S. DOE research initiative. In addition, we explore how these deployment pathways may impact the electricity system, electricity consumers, the environment, and the wind-related workforce. Overall, our analysis finds that wind technology innovation can have consequential implications for future wind power development throughout the United States, impact the broader electricity system, lower electric system and consumer costs, provide potential environmental benefits, and grow the U.S. wind workforce.

  16. High penetration wind generation impacts on spot prices in the Australian national electricity market

    International Nuclear Information System (INIS)

    Cutler, Nicholas J.; Boerema, Nicholas D.; MacGill, Iain F.; Outhred, Hugh R.

    2011-01-01

    This paper explores wind power integration issues for the South Australian (SA) region of the Australian National Electricity Market (NEM) by assessing the interaction of regional wind generation, electricity demand and spot prices over 2 recent years of market operation. SA's wind energy penetration has recently surpassed 20% and it has only a limited interconnection with other regions of the NEM. As such, it represents an interesting example of high wind penetration in a gross wholesale pool market electricity industry. Our findings suggest that while electricity demand continues to have the greatest influence on spot prices in SA, wind generation levels have become a significant secondary influence, and there is an inverse relationship between wind generation and price. No clear relationship between wind generation and demand has been identified although some periods of extremely high demand may coincide with lower wind generation. Periods of high wind output are associated with generally lower market prices, and also appear to contribute to extreme negative price events. The results highlight the importance of electricity market and renewable policy design in facilitating economically efficient high wind penetrations. - Highlights: → In South Australia (SA) wind generation is having an influence on market prices. → Little or no correlation is found between wind generation and demand. → Wind farms in SA are receiving a lower average price than in other States. → The results highlight the importance of appropriate electricity market design.

  17. Stochastic Optimal Wind Power Bidding Strategy in Short-Term Electricity Market

    DEFF Research Database (Denmark)

    Hu, Weihao; Chen, Zhe; Bak-Jensen, Birgitte

    2012-01-01

    minimization problem for trading wind power in the short-term electricity market is described, to help the wind power owners optimize their bidding strategy. Stochastic optimization and a Monte Carlo method are adopted to find the optimal bidding strategy for trading wind power in the short-term electricity...... market in order to deal with the uncertainty of the regulation price, the activated regulation of the power system and the forecasted wind power generation. The Danish short-term electricity market and a wind farm in western Denmark are chosen as study cases due to the high wind power penetration here....... Simulation results show that the stochastic optimal bidding strategy for trading wind power in the Danish short-term electricity market is an effective measure to maximize the revenue of the wind power owners....

  18. Forecasting Electricity Spot Prices Accounting for Wind Power Predictions

    DEFF Research Database (Denmark)

    Jónsson, Tryggvi; Pinson, Pierre; Nielsen, Henrik Aalborg

    2013-01-01

    A two-step methodology for forecasting of electricity spot prices is introduced, with focus on the impact of predicted system load and wind power generation. The nonlinear and nonstationary influence of these explanatory variables is accommodated in a first step based on a nonparametric and time......-varying regression model. In a second step, time-series models, i.e., ARMA and Holt–Winters, are applied to account for residual autocorrelation and seasonal dynamics. Empirical results are presented for out-of-sample forecasts of day-ahead prices in the Western Danish price area of Nord Pool's Elspot, during a two...

  19. Comparing Sources of Damping of Cross-Wind Motion

    DEFF Research Database (Denmark)

    Tarp-Johansen, Niels Jacob; Andersen, Lars; Christensen, Erik Damgaard

    2009-01-01

    practise plays a key role in this. The questions are: does more damping exist and is one of the sources of damping the main contributor allowing for site-independent guidelines. The aim of this paper is to address these issues. It is demonstrated that tower dampers are important in order to tackle...... importance of the sources of damping clearly depends on the damping forces caused, but equally important is the displacements at the point of attack of the forces which is decisive for the amount of mechanical work performed, i.e. damping acting at the tower base has less potential than damping acting...... driving if there is a significant wind-wave misalignment. In order to avoid unnecessary conservatism it is therefore important to know if there is more damping available than assumed in the today's practise. The paper treats this issue. Contents Based on engineering judgement it is expected...

  20. Utilizing the energy from induced wind produce by highway vehicle motion

    International Nuclear Information System (INIS)

    Abas Abd Wahab; Tong, C.W.

    2000-01-01

    A research work has been conducted at the Faculty of mechanical Engineering, Universiti Teknologi Malaysia to utilize energy from airflow induced by moving vehicles along the highway for advertising and signboard lighting. Series of data collections have been made at Km 20 Johor Bahru - Kuala Lumpur Plus Highway. Wind anemometer equipped with data recorder has been placed at the highway divider to measure the wind speed induced by the vehicles moving from Johor Bahru to Kuala Lumpur and vice versa. From the data analysis it has been found that the to and from Kuala Lumpur motion of the vehicles induced a stable and continuous source of airflow (wind) ranges from 2 to 4 m/s. The energy in this induced wind has been estimated and has the potential to be used for the above said purpose. Five design models have been tested in the Faculty of mechanical Engineering Low Speed Wind Tunnel and the twisted vertical blades with circular end covers has proven to be the most efficient and suitable. The optimum sizing of the vertical axis wind turbine has also been determined. The details of the collection of wind induced data and analysis, estimation of energy content, the vertical axis wind turbine models testing and results are presented in this paper. (Author)

  1. Winds of change: How high wind penetrations will affect investment incentives in the GB electricity sector

    International Nuclear Information System (INIS)

    Steggals, Will; Gross, Robert; Heptonstall, Philip

    2011-01-01

    Wind power is widely expected to expand rapidly in Britain over the next decade. Large amounts of variable wind power on the system will increase market risks, with prices more volatile and load factors for conventional thermal plant lower and more uncertain. This extra market risk may discourage investment in generation capacity. Financial viability for thermal plant will be increasingly dependent on price spikes during periods of low wind. Increased price risk will also make investment in other forms of low-carbon generation (e.g. nuclear power) more challenging. A number of policies can reduce the extent to which generators are exposed to market risks and encourage investment. However, market risks play a fundamental role in shaping efficient investment and dispatch patterns in a liberalised market. Therefore, measures to improve price signals and market functioning (such as a stronger carbon price and developing more responsive demand) are desirable. However, the scale of the investment challenge and increased risk mean targeted measures to reduce (although not eliminate) risk exposure, such as capacity mechanisms and fixed price schemes, may have increasing merit. The challenge for policy is to strike the right balance between market and planned approaches. - Research highlights: → Analyses how increases penetrations of wind power effect electricity market functioning. → Assesses the impacts of this on investment incentives for different technologies. → Discusses implications for policy and market design.

  2. Final report: Task 4a.2 20% wind scenario assessment of electric grid operational features

    Energy Technology Data Exchange (ETDEWEB)

    Toole, Gasper L. [Los Alamos National Laboratory

    2009-01-01

    Wind integration modeling in electricity generation capacity expansion models is important in that these models are often used to inform political or managerial decisions. Poor representation of wind technology leads to under-estimation of wind's contribution to future energy scenarios which may hamper growth of the industry. The NREL's Wind Energy Deployment System (WinDS) model provides the most detailed representation of geographically disperse renewable resources and the optimization of transmission expansion to access these resources. Because WinDS was selected as the primary modeling tool for the 20% Wind Energy by 2030 study, it is the ideal tool for supplemental studies of the transmission expansion results. However, as the wind industry grows and knowledge related to the wind resource and integration of wind energy into the electric system develops, the WinDS model must be continually improved through additional data and innovative algorithms to capture the primary effects of variable wind generation. The detailed representation of wind technology in the WinDS model can be used to provide improvements to the simplified representation of wind technology in other capacity expansion models. This task did not employ the WinDS model, but builds from it and its results. Task 4a.2 provides an assessment of the electric grid operational features of the 20% Wind scenario and was conducted using power flow models accepted by the utility industry. Tasks 2 provides information regarding the physical flow of electricity on the electric grid which is a critical aspect of infrastructure expansion scenarios. Expanding transmission infrastructure to access remote wind resource in a physically realizable way is essential to achieving 20% wind energy by 2030.

  3. Research of Short-range Missile Motion in Terms of Different Wind Loads

    Directory of Open Access Journals (Sweden)

    A. N. Klishin

    2015-01-01

    Full Text Available When modeling the aircraft motion it is advisable to choose a particular model of the Earth, depending both on the task and on the required accuracy of calculation. The article describes various models of the Earth, such as the flat Earth with a plane-parallel field of gravity, spherical and non-rotating Earth with a plane-parallel field of gravity, spherical and non-rotating Earth with a central gravitational field, spherical and non-rotating Earth, taking into account the polar flattening of the Earth, spherical Earth based compression and polar daily rotation. The article also considers the influence of these models on the motion of the selected aircraft.To date, there is technical equipment to provide highly accurate description of the Earthshape, gravitational field, etc. The improved accuracy of the Earth model description results in more correct description of the trajectory and motion parameters of a ballistic missile. However, for short ranges (10-20 km this accuracy is not essential, and, furthermore, it increases time of calculation. Therefore, there is a problem of choosing the optimal description of the Earth parameters.The motion in the model of the Earth, which takes into account a daily rotation of the planet and polar flattening, is discussed in more detail, and the geographical latitude impact on coordinates of the points of fall of a ballistic missile is analyzed on the basis of obtained graphs.The article individually considers a problem of the wind effect on the aircraft motion and defines dependences of the missile motion on the parameters of different wind loads, such as wind speed and height of its action.A mathematical model of the missile motion was built and numerically integrated, using the Runge-Kutta 4th order method, for implementation and subsequent analysis.Based on the analysis of the calculation results in the abovementioned models of the Earth, differences in impact of these models on the parameters of the

  4. Wind energy for the electricity supply; Energie eolienne pour la fourniture d'electricite

    Energy Technology Data Exchange (ETDEWEB)

    Noel, J.M

    2009-01-15

    This document deals with the today implementing of the wind energy for the supply of electricity in the electric power distribution network. It is based on the technologies developed to prepare the wind turbines installation, build the turbines of these power plants and plan the non continuous and weakly forecasting supply of the wind electricity with the current operating of the networks. (A.L.B.)

  5. Sun, wind and electric generation; Sol, viento y generacion electrica

    Energy Technology Data Exchange (ETDEWEB)

    Huacuz Villamar, Jorge M. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1995-12-31

    A description is made of the electric generation known as the photovoltaic-wind power hybrid systems at the generation station of X-Calak which is located in the zone known as Punta Herrero-X-Calak Corridor, in the Southern coast of the Quintana Roo State. This is a technology in development, in which the solar and the wind energy are combined, to offer an alternative of electric generation that can be economical, reliable and of low impact on the environment. Mention is made of the experiences gathered in this station as well as the results obtained [Espanol] Se describe la tecnologia de generacion electrica conocida como sistemas hibridos fotovoltaico-eolico en la planta generadora de X-Calak, la cual esta localizada en la zona conocida como el corredor Punta Herrero-X-Calak, en la costa sur del estado de Quintana Roo. Esta es una tecnologia en desarrollo, en donde se combina la energia solar y energia eolica, para ofrecer una alternativa de generacion electrica que pretende ser economica, confiable y de bajo impacto sobre el medio ambiente. Se mencionan las experiencias obtenidas en esta planta asi como los resultados obtenidos

  6. Wind power integration studies using a multi-stage stochastic electricity system model

    DEFF Research Database (Denmark)

    Meibom, Peter; Barth, R.; Brand, H.

    2007-01-01

    A large share of integrated wind power causes technical and financial impacts on the operation of the existing electricity system due to the fluctuating behaviour and unpredictability of wind power. The presented stochastic electricity market model optimises the unit commitment considering four...... kinds of electricity markets (e.g. a spot and balancing market) and taking into account the stochastic behaviour of the wind power generation and of the prediction error. It can be used for the evaluation of varying electricity prices and system costs due to wind power integration...

  7. Potential for increased wind-generated electricity utilization using heat pumps in urban areas

    International Nuclear Information System (INIS)

    Waite, Michael; Modi, Vijay

    2014-01-01

    Highlights: • Large-scale wind power and increased electric heat pumps were evaluated. • A deterministic model of wind power and electricity demand was developed. • Sub-models for space heating and domestic hot water demand were developed. • Increased use of heat pumps can improve the viability of large-scale wind power. • Larger wind power capacity can meet a target utilization rate with more heat pumps. - Abstract: The U.S. has substantial wind power potential, but given wind’s intermittent availability and misalignment with electricity demand profiles, large-scale deployment of wind turbines could result in high electricity costs due to energy storage requirements or low utilization rates. While fuel switching and heat pumps have been proposed as greenhouse gas (GHG) emissions and energy reduction strategies at the building scale, this paper shows that heat pump adoption could have additional system-wide benefits by increasing the utilization of wind-generated electricity. A model was developed to evaluate the effects of coupling large-scale wind power installations in New York State with increased use of electric heat pumps to meet a portion of space heating and domestic hot water (DHW) demands in New York City. The analysis showed significant increases in wind-generated electricity utilization with increased use of heat pumps, allowing for higher installed capacity of wind power. One scenario indicates that 78.5% annual wind-generated electricity utilization can be achieved with 3 GW of installed wind power capacity generated electricity equal to 20% of existing NYC annual electricity demand; if 20% of space heating and DHW demands are provided by heat pumps, the 78.5% utilization rate can be achieved with an increase of total wind power capacity to 5 GW. Therefore, this integrated supply–demand approach could provide additional system-wide emissions reductions

  8. Coupled flap and edge wise blade motion due to a quadratic wind force definition

    International Nuclear Information System (INIS)

    Van der Male, P; Van Dalen, K N

    2014-01-01

    The wind force on turbine blades, consisting of a drag and lift component, depends nonlinearly on the relative wind velocity. This relative velocity comprises mean wind speed, wind speed fluctuations and the structural response velocity. The nonlinear wind excitation couples the flap wise and edge wise response of a turbine blade. To analyze this motion coupling, an isolated blade is modelled as a continuous cantilever beam and corresponding nonlinear expressions for the drag and lift force are defined. After reduction of the model on the basis of its principal modes, the nonlinear response up to the second order is derived with the help of a Volterra series expansion and the harmonic probing technique. This technique allows for response analysis in the frequency domain, via which the combined flap and edge wise responses can easily be visualized. As a specific case, the characteristics of the NREL5 turbine blades are adopted. For both non-operating and operating conditions, blade responses in a turbulent wave field, based on a Kaimal spectrum, are determined. The second-order responses are shown to cause additional motion coupling, and moreover, are proven not to be negligible straightforwardly

  9. PROVIDING QUALITY OF ELECTRIC POWER IN ELECTRIC POWER SYSTEM IN PARALLEL OPERATION WITH WIND TURBINE

    Directory of Open Access Journals (Sweden)

    Yu. A. Rolik

    2016-01-01

    Full Text Available The problem of providing electric power quality in the electric power systems (EPS that are equipped with sufficiently long air or cable transmission lines is under consideration. This problem proved to be of particular relevance to the EPS in which a source of electrical energy is the generator of wind turbines since the wind itself is an instable primary energy source. Determination of the degree of automation of voltage regulation in the EPS is reduced to the choice of methods and means of regulation of power quality parameters. The concept of a voltage loss and the causes of the latter are explained by the simplest power system that is presented by a single-line diagram. It is suggested to regulate voltage by means of changing parameters of the network with the use of the method of reducing loss of line voltage by reducing its reactance. The latter is achieved by longitudinal capacitive compensation of the inductive reactance of the line. The effect is illustrated by vector diagrams of currents and voltages in the equivalent circuits of transmission lines with and without the use of longitudinal capacitive compensation. The analysis of adduced formulas demonstrated that the use of this method of regulation is useful only in the systems of power supply with a relatively low power factor (cosφ < 0.7 to 0.9. This power factor is typical for the situation of inclusion the wind turbine with asynchronous generator in the network since the speed of wind is instable. The voltage regulation fulfilled with the aid of the proposed method will make it possible to provide the required quality of the consumers’ busbars voltage in this situation. In is turn, it will make possible to create the necessary conditions for the economical transmission of electric power with the lowest outlay of reactive power and the lowest outlay of active power losses.

  10. The sun and the wind. Green and gray electricity

    International Nuclear Information System (INIS)

    Pryor, A.

    1999-01-01

    Electricity generation is one of the essential technologies that sustain modern life. When the electricity is cut off life in a modern city is unendurable. It is as vital as transport and communication. Yet it is a poorly understood technology. For most people, it comes from a socket on the wall. Knowing so little of its origin, they fantasise about 'green' sources like the sun and the wind and think it is sheer perversity for engineers to persevere with 'grey' sources like grubby, coal-burning power stations or nuclear reactors. Energy is a central concept of modern physics. This led on to the powerful idea of the conservation of energy: the sum of energy in all its forms stays constant in a closed system; energy can neither be created nor destroyed. But if that is so, people may be puzzled by all this talk of our profligate energy consumption leading to an 'energy crisis'. In strict physics although energy is not consumed it is degraded to lower temperatures and made less available. But physics offers us no convenient definition oi available energy and, when discussing the so-called energy crisis it is probably better not to use the word 'energy'. The crisis is real enough but it boils down to two particular problems: (i) we are running short of fuel for electricity generation; (ii) there are looming shortages of portable fuel (liquid or gas), above all for our cars, trucks, ships ant aeroplanes, but also for industrial and domestic heating. These are the two key problems: electricity generation and portable fuel. Moreover, though the final exhaustion of the world's reserves of coal, oil, and gas may not happen for many decades, they are finite and the end is in sight. Also there is widespread concern about the atmospheric contamination which comes from burning fossil fuels. In this essay the author discusses electricity generation alone, where there are realistic alternatives to fossil fuels: nuclear reactors and hydroelectricity generators, but not, we suggest

  11. Determination of recoverable wind energy for electricity generation ...

    African Journals Online (AJOL)

    fundamental step in planning a wind energy project and exhaustive knowledge of the wind characteristic at a site of installation is needed to estimate the performance of a wind energy conversion system. The current paper presents an investigation of the wind power potential using real wind data for five sites in Tunisia: ...

  12. Simulation Tool to Assess Mechanical and Electrical Stresses on Wind Turbine Generators: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Singh, M.; Muljadi, E.; Gevorgian, V.; Jonkman, J.

    2013-10-01

    Wind turbine generators (WTGs) consist of many different components to convert kinetic energy of the wind into electrical energy for end users. Wind energy is accessed to provide mechanical torque for driving the shaft of the electrical generator. The conversion from wind power to mechanical power is governed by the aerodynamic conversion. The aerodynamic-electrical-conversion efficiency of a WTGis influenced by the efficiency of the blades, the gearbox, the generator, and the power converter. This paper describes the use of MATLAB/Simulink to simulate the electrical and grid-related aspects of a WTG coupled with the FAST aero-elastic wind turbine computer-aided engineering tool to simulate the aerodynamic and mechanical aspects of a WTG. The combination of the two enables studiesinvolving both electrical and mechanical aspects of a WTG. This digest includes some examples of the capabilities of the FAST and MATLAB coupling, namely the effects of electrical faults on the blade moments.

  13. A proposed national wind power R and D program. [offshore wind power system for electric energy supplies

    Science.gov (United States)

    Heronemus, W.

    1973-01-01

    An offshore wind power system is described that consists of wind driven electrical dc generators mounted on floating towers in offshore waters. The output from the generators supplies underwater electrolyzer stations in which water is converted into hydrogen and oxygen. The hydrogen is piped to shore for conversion to electricity in fuel cell stations. It is estimated that this system can produce 159 x 10 to the ninth power kilowatt-hours per year. It is concluded that solar energy - and that includes wind energy - is the only way out of the US energy dilemma in the not too distant future.

  14. Experimental Study on Influence of Pitch Motion on the Wake of a Floating Wind Turbine Model

    Directory of Open Access Journals (Sweden)

    Stanislav Rockel

    2014-03-01

    Full Text Available Wind tunnel experiments were performed, where the development of the wake of a model wind turbine was measured using stereo Particle Image Velocimetry to observe the influence of platform pitch motion. The wakes of a classical bottom fixed turbine and a streamwise oscillating turbine are compared. Results indicate that platform pitch creates an upward shift in all components of the flow and their fluctuations. The vertical flow created by the pitch motion as well as the reduced entrainment of kinetic energy from undisturbed flows above the turbine result in potentially higher loads and less available kinetic energy for a downwind turbine. Experimental results are compared with four wake models. The wake models employed are consistent with experimental results in describing the shapes and magnitudes of the streamwise velocity component of the wake for a fixed turbine. Inconsistencies between the model predictions and experimental results arise in the floating case particularly regarding the vertical displacement of the velocity components of the flow. Furthermore, it is found that the additional degrees of freedom of a floating wind turbine add to the complexity of the wake aerodynamics and improved wake models are needed, considering vertical flows and displacements due to pitch motion.

  15. 75 FR 6020 - Electrical Interconnection of the Lower Snake River Wind Energy Project

    Science.gov (United States)

    2010-02-05

    ... DEPARTMENT OF ENERGY Bonneville Power Administration Electrical Interconnection of the Lower Snake River Wind Energy Project AGENCY: Bonneville Power Administration (BPA), Department of Energy (DOE... would be generated from their proposed Lower Snake River Wind Energy Project (Wind Project) in Garfield...

  16. The role of hydrogen in high wind energy penetration electricity systems: the Irish case

    International Nuclear Information System (INIS)

    Gonzalez, A.; McKeogh, E.; Gallachoir, B.O.

    2004-01-01

    The deployment of wind energy is constrained by wind uncontrollability, which poses operational problems on the electricity supply system at high penetration levels, lessening the value of wind-generated electricity to a significant extent. This paper studies the viability of hydrogen production via electrolysis using wind power that cannot be easily accommodated on the system. The potential benefits of hydrogen and its role in enabling a large penetration of wind energy are assessed, within the context of the enormous wind energy resource in Ireland. The exploitation of this wind resource may in the future give rise to significant amounts of surplus wind electricity, which could be used to produce hydrogen, the zero-emissions fuel that many experts believe will eventually replace fossil fuels in the transport sector. In this paper the operation of a wind powered hydrogen production system is simulated and optimised. The results reveal that, even allowing for significant cost-reductions in electrolyser and associated balance-of-plant equipment, low average surplus wind electricity cost and a high hydrogen market price are also necessary to achieve the economic viability of the technology. These conditions would facilitate the installation of electrolysis units of sufficient capacity to allow an appreciable increase in installed wind power in Ireland. The simulation model was also used to determine the CO 2 abatement potential associated with the wind energy/hydrogen production. (author)

  17. EMMI-Electric solar wind sail facilitated Manned Mars Initiative

    Science.gov (United States)

    Janhunen, Pekka; Merikallio, Sini; Paton, Mark

    2015-08-01

    The novel propellantless electric solar wind sail concept promises efficient low thrust transportation in the Solar System outside Earth's magnetosphere. Combined with asteroid mining to provide water and synthetic cryogenic rocket fuel in orbits of Earth and Mars, possibilities for affordable continuous manned presence on Mars open up. Orbital fuel and water enable reusable bidirectional Earth-Mars vehicles for continuous manned presence on Mars and allow smaller fuel fraction of spacecraft than what is achievable by traditional means. Water can also be used as radiation shielding of the manned compartment, thus reducing the launch mass further. In addition, the presence of fuel in the orbit of Mars provides the option for an all-propulsive landing, thus potentially eliminating issues of heavy heat shields and augmenting the capability of pinpoint landing. With this E-sail enabled scheme, the recurrent cost of continuous bidirectional traffic between Earth and Mars might ultimately approach the recurrent cost of running the International Space Station, ISS.

  18. Analysis methods for wind turbine control and electrical system dynamics

    Science.gov (United States)

    Hinrichsen, E. N.

    1995-01-01

    The integration of new energy technologies into electric power systems requires methods which recognize the full range of dynamic events in both the new generating unit and the power system. Since new energy technologies are initially perceived as small contributors to large systems, little attention is generally paid to system integration, i.e. dynamic events in the power system are ignored. As a result, most new energy sources are only capable of base-load operation, i.e. they have no load following or cycling capability. Wind turbines are no exception. Greater awareness of this implicit (and often unnecessary) limitation is needed. Analysis methods are recommended which include very low penetration (infinite bus) as well as very high penetration (stand-alone) scenarios.

  19. Wind up with continuous intra-day electricity markets? The integration of large-share wind power generation in Denmark

    International Nuclear Information System (INIS)

    Karanfil, Fatih; Li, Yuanjing

    2015-01-01

    This paper suggests an innovative idea to examine the functionality of an electricity intra-day market by testing causality among its fundamental components. As fluctuations of poorly predicted wind power generation are challenging the stability of the current electricity system, an intra-day market design can play an important role in managing wind forecast errors. Using Danish and Nordic data, it investigates the main drivers of the price difference between the intra-day and day-ahead markets, and causality between wind forecast errors and their counterparts. Our results show that the wind and conventional generation forecast errors significantly cause the intra-day price to differ from the day-ahead price, and that the relative intra-day price decreases with the unexpected amount of wind generation. Cross-border electricity exchanges are found to be important to handle wind forecast errors. Additionally, some zonal differences with respect to both causality and impulse responses are detected. This paper provides the first evidence on the persuasive functioning of the intra-day market in the case of Denmark, whereby intermittent production deviations are effectively reduced, and wind forecast errors are jointly handled through the responses from demand, conventional generation, and intra-day international electricity trade. (authors)

  20. Benefits for wind energy in electricity markets from using short term wind power prediction tools: a simulation study

    International Nuclear Information System (INIS)

    Usaola, J.; Ravelo, O.; Gonzalez, G.; Soto, F.; Davila, M.C.; Diaz-Guerra, B.

    2004-01-01

    One of the characteristics of wind energy, from the grid point of view, is its non-dispatchability, i.e. generation cannot be ordered, hence integration in electrical networks may be difficult. Short-term wind power prediction-tools could make this integration easier, either by their use by the grid System Operator, or by promoting the participation of wind farms in the electricity markets and using prediction tools to make their bids in the market. In this paper, the importance of a short-term wind power-prediction tool for the participation of wind energy systems in electricity markets is studied. Simulations, according to the current Spanish market rules, have been performed to the production of different wind farms, with different degrees of accuracy in the prediction tool. It may be concluded that income from participation in electricity markets is increased using a short-term wind power prediction-tool of average accuracy. This both marginally increases income and also reduces the impact on system operation with the improved forecasts. (author)

  1. A New Position Measurement System Using a Motion-Capture Camera for Wind Tunnel Tests

    Directory of Open Access Journals (Sweden)

    Yousok Kim

    2013-09-01

    Full Text Available Considering the characteristics of wind tunnel tests, a position measurement system that can minimize the effects on the flow of simulated wind must be established. In this study, a motion-capture camera was used to measure the displacement responses of structures in a wind tunnel test, and the applicability of the system was tested. A motion-capture system (MCS could output 3D coordinates using two-dimensional image coordinates obtained from the camera. Furthermore, this remote sensing system had some flexibility regarding lab installation because of its ability to measure at relatively long distances from the target structures. In this study, we performed wind tunnel tests on a pylon specimen and compared the measured responses of the MCS with the displacements measured with a laser displacement sensor (LDS. The results of the comparison revealed that the time-history displacement measurements from the MCS slightly exceeded those of the LDS. In addition, we confirmed the measuring reliability of the MCS by identifying the dynamic properties (natural frequency, damping ratio, and mode shape of the test specimen using system identification methods (frequency domain decomposition, FDD. By comparing the mode shape obtained using the aforementioned methods with that obtained using the LDS, we also confirmed that the MCS could construct a more accurate mode shape (bending-deflection mode shape with the 3D measurements.

  2. Global MHD Simulations of the Earth's Bow Shock Shape and Motion Under Variable Solar Wind Conditions

    Science.gov (United States)

    Mejnertsen, L.; Eastwood, J. P.; Hietala, H.; Schwartz, S. J.; Chittenden, J. P.

    2018-01-01

    Empirical models of the Earth's bow shock are often used to place in situ measurements in context and to understand the global behavior of the foreshock/bow shock system. They are derived statistically from spacecraft bow shock crossings and typically treat the shock surface as a conic section parameterized according to a uniform solar wind ram pressure, although more complex models exist. Here a global magnetohydrodynamic simulation is used to analyze the variability of the Earth's bow shock under real solar wind conditions. The shape and location of the bow shock is found as a function of time, and this is used to calculate the shock velocity over the shock surface. The results are compared to existing empirical models. Good agreement is found in the variability of the subsolar shock location. However, empirical models fail to reproduce the two-dimensional shape of the shock in the simulation. This is because significant solar wind variability occurs on timescales less than the transit time of a single solar wind phase front over the curved shock surface. Empirical models must therefore be used with care when interpreting spacecraft data, especially when observations are made far from the Sun-Earth line. Further analysis reveals a bias to higher shock speeds when measured by virtual spacecraft. This is attributed to the fact that the spacecraft only observes the shock when it is in motion. This must be accounted for when studying bow shock motion and variability with spacecraft data.

  3. Small Wind Electric Systems: A Guide Produced for the Tennessee Valley Authority (Revised) (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2009-06-01

    Small Wind Electric Systems: A Guide Produced for the Tennessee Valley Authority provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a regional wind resource map and a list of incentives and contacts for more information.

  4. Small Wind Electric Systems: A Maryland Consumer's Guide (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    2009-08-01

    Small Wind Electric Systems: A Maryland Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a regional wind resource map and a list of incentives and contacts for more information.

  5. Optimal Operation of Plug-In Electric Vehicles in Power Systems with High Wind Power Penetrations

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Chen, Zhe

    2013-01-01

    The Danish power system has a large penetration of wind power. The wind fluctuation causes a high variation in the power generation, which must be balanced by other sources. The battery storage based Plug-In Electric Vehicles (PEV) may be a possible solution to balance the wind power variations...... in the power systems with high wind power penetrations. In this paper, the integration of plug-in electric vehicles in the power systems with high wind power penetrations is proposed and discussed. Optimal operation strategies of PEV in the spot market are proposed in order to decrease the energy cost for PEV...... owners. Furthermore, the application of battery storage based aggregated PEV is analyzed as a regulation services provider in the power system with high wind power penetrations. The western Danish power system where the total share of annual wind power production is more than 27% of the electrical energy...

  6. Generation Ratio Availability Assessment of Electrical Systems for Offshore Wind Farms

    DEFF Research Database (Denmark)

    Zhao, Menghua; Chen, Zhe; Blaabjerg, Frede

    2007-01-01

    An availability index, Generation Ratio Availability (GRA), is proposed to evaluate the electrical system of offshore wind farms (OWF). The GRA is the probability that at least a certain percent of wind power could be transferred to the grid system through the concerned electrical system. The GRA...

  7. Vibration-based damage detection in wind turbine blades using Phase-based Motion Estimation and motion magnification

    Science.gov (United States)

    Sarrafi, Aral; Mao, Zhu; Niezrecki, Christopher; Poozesh, Peyman

    2018-05-01

    Vibration-based Structural Health Monitoring (SHM) techniques are among the most common approaches for structural damage identification. The presence of damage in structures may be identified by monitoring the changes in dynamic behavior subject to external loading, and is typically performed by using experimental modal analysis (EMA) or operational modal analysis (OMA). These tools for SHM normally require a limited number of physically attached transducers (e.g. accelerometers) in order to record the response of the structure for further analysis. Signal conditioners, wires, wireless receivers and a data acquisition system (DAQ) are also typical components of traditional sensing systems used in vibration-based SHM. However, instrumentation of lightweight structures with contact sensors such as accelerometers may induce mass-loading effects, and for large-scale structures, the instrumentation is labor intensive and time consuming. Achieving high spatial measurement resolution for a large-scale structure is not always feasible while working with traditional contact sensors, and there is also the potential for a lack of reliability associated with fixed contact sensors in outliving the life-span of the host structure. Among the state-of-the-art non-contact measurements, digital video cameras are able to rapidly collect high-density spatial information from structures remotely. In this paper, the subtle motions from recorded video (i.e. a sequence of images) are extracted by means of Phase-based Motion Estimation (PME) and the extracted information is used to conduct damage identification on a 2.3-m long Skystream® wind turbine blade (WTB). The PME and phased-based motion magnification approach estimates the structural motion from the captured sequence of images for both a baseline and damaged test cases on a wind turbine blade. Operational deflection shapes of the test articles are also quantified and compared for the baseline and damaged states. In addition

  8. Combined hydro-wind generation bids in a pool-based electricity market

    International Nuclear Information System (INIS)

    Angarita, Jorge L.; Usaola, Julio; Martinez-Crespo, Jorge

    2009-01-01

    Present regulatory trends are promoting the direct participation of wind energy in electricity markets. The final result of these markets sets the production scheduling for the operation time, including a power commitment from the wind generators. However, wind resources are uncertain, and the final power delivered usually differs from the initial power committed. This imbalance produces an overcost in the system, which must be paid by those who produce it, e.g., wind generators among others. As a result, wind farm revenue decreases, but it could increase by allowing wind farms to submit their bids to the markets together with a hydro generating unit, which may easily modify its production according to the expected imbalance. This paper presents a stochastic optimization technique that maximizes the joint profit of hydro and wind generators in a pool-based electricity market, taking into account the uncertainty of wind power prediction. (author)

  9. Selected Aspects Of Building, Operation And Environmental Impact Of Offshore Wind Power Electric Plants

    Directory of Open Access Journals (Sweden)

    Mroziński Adam

    2015-04-01

    Full Text Available This paper describes essence of work of offshore wind power electric plants and crucial aspects of their building and operating. Prospects for development of global, European and domestic markets of offshore wind power industry have been delineated. A comparative analysis of environmental impact of an offshore and land-based 2MW wind power electric plant has been performed by using LCA method and Ecoindex – 99 (Ekowskaźnik 99 modelling.

  10. Reliability Assessment of Wind Farm Electrical System Based on a Probability Transfer Technique

    Directory of Open Access Journals (Sweden)

    Hejun Yang

    2018-03-01

    Full Text Available The electrical system of a wind farm has a significant influence on the wind farm reliability and electrical energy yield. The disconnect switch installed in an electrical system cannot only improve the operating flexibility, but also enhance the reliability for a wind farm. Therefore, this paper develops a probabilistic transfer technique for integrating the electrical topology structure, the isolation operation of disconnect switch, and stochastic failure of electrical equipment into the reliability assessment of wind farm electrical system. Firstly, as the traditional two-state reliability model of electrical equipment cannot consider the isolation operation, so the paper develops a three-state reliability model to replace the two-state model for incorporating the isolation operation. In addition, a proportion apportion technique is presented to evaluate the state probability. Secondly, this paper develops a probabilistic transfer technique based on the thoughts that through transfer the unreliability of electrical system to the energy transmission interruption of wind turbine generators (WTGs. Finally, some novel indices for describing the reliability of wind farm electrical system are designed, and the variance coefficient of the designed indices is used as a convergence criterion to determine the termination of the assessment process. The proposed technique is applied to the reliability assessment of a wind farm with the different topologies. The simulation results show that the proposed techniques are effective in practical applications.

  11. statistical analysis of wind speed for electrical power generation

    African Journals Online (AJOL)

    HOD

    Keywords: Wind speed - probability - density function – wind energy conversion system- statistical analyses. 1. INTRODUCTION. In order ..... "Statistical analysis of wind speed distribution based on six Weibull Methods for wind power evaluation in. Garoua, Cameroon," Revue des Energies. Renouvelables, vol. 18, no. 1, pp.

  12. Wind energy as a significant source of electricity for the United States

    International Nuclear Information System (INIS)

    Nix, R.G.

    1996-06-01

    This paper discusses wind energy and its potential to significantly impact the generation of electricity within the US. The principles and the equipment used to convert wind energy to electricity are described, as is the status of current technology. Markets and production projections are given. There is discussion of the advances required to reduce the selling cost of electricity generated from the wind from today's price of about $0.05 per kilowatt-hour to full cost-competitiveness with gas- and coal-based electricity

  13. Simulation of an offshore wind farm using fluid power for centralized electricity generation

    Directory of Open Access Journals (Sweden)

    A. Jarquin Laguna

    2017-07-01

    Full Text Available A centralized approach for electricity generation within a wind farm is explored through the use of fluid power technology. This concept considers a new way of generation, collection and transmission of wind energy inside a wind farm, in which electrical conversion does not occur during any intermediate conversion step before the energy has reached the offshore central platform. A numerical model was developed to capture the relevant physics from the dynamic interaction between different turbines coupled to a common hydraulic network and controller. This paper presents a few examples of the time domain simulation results for a hypothetical hydraulic wind farm subject to turbulent wind conditions. The performance and operational parameters of individual turbines are compared with those of a reference wind farm based on conventional wind turbine generator technology using the same wind farm layout and environmental conditions. For the presented case studies, results indicate that the individual wind turbines are able to operate within operational limits. Despite the stochastic turbulent wind conditions and wake effects, the hydraulic wind farm is able to produce electricity with reasonable performance in both below and above rated conditions. With the current pressure control concept, a continuous operation of the hydraulic wind farm is shown including the full stop of one or more turbines.

  14. Evaluating the impact of electrical grid connection on the wind turbine performance for Hofa wind farm scheme in Jordan

    International Nuclear Information System (INIS)

    Abderrazzaq, M.H.; Aloquili, O.

    2008-01-01

    The growth of wind energy is attributed to the development of turbine size and the increase in number of units in each wind farm. The current modern design of large wind turbines (WT) is directed towards producing efficient, sensitive and reliable units. To achieve this goal, modern turbines are equipped with several devices which are operated with highly advanced electronic circuits. Sensing instruments, measuring devices and control processes of major systems and subsystems are based on various types of electronic apparatus and boards. These boards are very sensitive to the voltage variations caused by abnormal conditions in both the turbine itself and the electric grid to which the wind farm is connected. This paper evaluates wind farm records and proposes a number of methods to overcome such obstacles associated with the design of large wind turbines. Several cases of grid abnormality such as sudden feeder interruption due to the short circuit, network disconnection, voltage variation and circuit breaker opening affecting wind turbines operation and availability are classified and presented. The weight of such impact is determined for each type of disturbances associated with electronic problems in the wind turbine. Wind turbine performance at Hofa wind farm scheme in Jordan is taken as a case study

  15. Electricity market design for facilitating the integration of wind energy. Experience and prospects with the Australian National Electricity Market

    International Nuclear Information System (INIS)

    MacGill, Iain

    2010-01-01

    Australia has been an early and enthusiastic adopter of both electricity industry restructuring and market-based environmental regulation. The Australian National Electricity Market (NEM) was established in 1999 and Australia also implemented one of the world's first renewable energy target schemes in 2001. With significant recent growth in wind generation, Australia provides an interesting case for assessing different approaches to facilitating wind integration into the electricity industry. Wind project developers in Australia must assess both potential energy market and Tradeable Green Certificate income streams when making investments. Wind-farm energy income depends on the match of its uncertain time varying output with the regional half hourly market price; a price that exhibits daily, weekly and seasonal patterns and considerable uncertainty. Such price signals assist in driving investments that maximize project value to the electricity industry as a whole, including integration costs and benefits for other participants. Recent NEM rule changes will formally integrate wind generation in the market's scheduling processes while a centralized wind forecasting system has also been introduced. This paper outlines experience to date with wind integration in the NEM, describes the evolution of market rules in response and assesses their possible implications for facilitating high future wind penetrations. (author)

  16. Wind power feed-in impact on electricity prices in Germany 2009-2013

    Directory of Open Access Journals (Sweden)

    François Benhmad

    2016-07-01

    Full Text Available Until quite recently no electricity system had faced the challenges associated with high penetrations of renewable energy sources (RES. In this paper, we carry out an empirical analysis for Germany, as a country with high penetration of wind energy, to investigate the well-known merit-order effect. Our main empirical findings suggest that the increasing share of wind power in-feed induces a decrease of electricity spot price level but an increase of spot prices volatility. Furthermore, the relationship between wind power and spot electricity prices can be strongly impacted by European electricity grids interconnection which behaves like a safety valve lowering volatility and limiting the price decrease. Therefore, the impacts of wind generated electricity on electricity spot markets are less clearly pronounced in interconnected systems.

  17. Environmental Benefits of Using Wind Generation to Power Plug-In Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Mahdi Hajian

    2011-08-01

    Full Text Available As alternatives to conventional vehicles, Plug-in Hybrid Electric Vehicles (PHEVs running off electricity stored in batteries could decrease oil consumption and reduce carbon emissions. By using electricity derived from clean energy sources, even greater environmental benefits are obtainable. This study examines the potential benefits arising from the widespread adoption of PHEVs in light of Alberta’s growing interest in wind power. It also investigates PHEVs’ capacity to mitigate natural fluctuations in wind power generation.

  18. Automated electric control of a vertical axis wind turbine in island operation

    OpenAIRE

    Högberg, Lars

    2009-01-01

    At the Division of Electricity at Uppsala University, a wind power concept has been developed. The concept uses a vertical axis wind turbine with a direct driven generator. The turbine has fixed blades, making speed control the only way to regulate power absorption. The speed is controlled with the electric load. The turbine is not self-starting, but can be started using the generator as a motor. In this project, an unsupervised electric system with automatic control is designed and construct...

  19. Research for Electric Brake Using NTC Thermistors on Micro Wind Turbine

    OpenAIRE

    Sugawara, Akira; Yamamoto, Kenichi; Yoshimi, Takeshi; Sato, Shingo; Tsurumaki, Akira; Ito, Tsuguru

    2006-01-01

    As a brake system for small wind turbine, mechanical brake and electric brake by the short circuit of 3-phase permanent magnet generator are used. However, an electric braking method may damage the rotor and/or blades by rapid stop of the generator revolution. Moreover, generator winding may also be damaged by large short-circuit current. In this paper, the electric braking method using NTC thermistors (negative temperature coefficient resistors) is proposed as a braking system for a cheaper ...

  20. Variable cross-section windings for efficiency improvement of electric machines

    Science.gov (United States)

    Grachev, P. Yu; Bazarov, A. A.; Tabachinskiy, A. S.

    2018-02-01

    Implementation of energy-saving technologies in industry is impossible without efficiency improvement of electric machines. The article considers the ways of efficiency improvement and mass and dimensions reduction of electric machines with electronic control. Features of compact winding design for stators and armatures are described. Influence of compact winding on thermal and electrical process is given. Finite element method was used in computer simulation.

  1. Wind Energy Based Electric Vehicle Charging Stations Sitting. A GIS/Wind Resource Assessment Approach

    Directory of Open Access Journals (Sweden)

    George Xydis

    2015-11-01

    Full Text Available The transportation sector is severely correlated with major problems in environment, citizens’ health, climate and economy. Issues such as traffic, fuel cost and parking space have make life more difficult, especially in the dense urban environment. Thus, there is a great need for the development of the electric vehicle (EV sector. The number of cars in cities has increased so much that the current transportation system (roads, parking places, traffic lights, etc. cannot accommodate them properly. The increasing number of vehicles does not affect only humans but also the environment, through air and noise pollution. According to EPA, the 39.2% of total gas emissions in 2007 was caused by transportation activities. Studies have shown that the pollutants are not only gathered in the major roads and/or highways but can travel depending on the meteorological conditions leading to generic pollution. The promotion of EVs and the charging stations are both equally required to be further developed in order EVs to move out of the cities and finally confront the range problem. In this work, a wind resource and a GIS analysis optimizes in a wider area the sitting of wind based charging stations and proposes an optimizing methodology.

  2. Small Wind Electric Systems: A Nebraska Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-12-01

    Small Wind Electric Systems: A Nebraska Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  3. Small Wind Electric Systems: A Colorado Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2006-12-01

    Small Wind Electric Systems: A Colorado Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  4. Small Wind Electric Systems: A U.S. Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: A U.S. Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  5. Small Wind Electric Systems: An Alaska Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-04-01

    Small Wind Electric Systems: An Alaska Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  6. Small Wind Electric Systems: A Montana Consumer's Guide (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    2006-04-01

    Small Wind Electric Systems: A Montana Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  7. Small Wind Electric Systems: An Oregon Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: An Oregon Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  8. Small Wind Electric Systems: An Illinois Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-04-01

    Small Wind Electric Systems: An Illinois Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  9. Small Wind Electric Systems: A Minnesota Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-04-01

    Small Wind Electric Systems: A Minnesota Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  10. Small Wind Electric Systems: An Oklahoma Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: An Oklahoma Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  11. Small Wind Electric Systems: A Kansas Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: A Kansas Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  12. Small Wind Electric Systems: A Utah Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: A Utah Consumer's Guide provides Utah consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  13. Small Wind Electric Systems: A Vermont Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-04-01

    Small Wind Electric Systems: A Vermont Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  14. Small Wind Electric Systems: An Ohio Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: An Ohio Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  15. Small Wind Electric Systems: A Washington Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: A Washington Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  16. Small Wind Electric Systems: A Maine Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: A Maine Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  17. Small Wind Electric Systems: A Hawaii Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: A Hawaii Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  18. Small Wind Electric Systems: A South Dakota Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-04-01

    Small Wind Electric Systems: A South Dakota Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  19. Small Wind Electric Systems: A North Dakota Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-04-01

    Small Wind Electric Systems: A North Dakota Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  20. Small Wind Electric Systems: A Virginia Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-01-01

    Small Wind Electric Systems: A Virginia Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  1. Small Wind Electric Systems: A Pennsylvania Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: A Pennsylvania Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  2. Small Wind Electric Systems: A Montana Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-01

    Small Wind Electric Systems: A Montana Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and economics. Topics include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  3. Small Wind Electric Systems: A North Carolina Consumer's Guide

    Energy Technology Data Exchange (ETDEWEB)

    2005-03-01

    Small Wind Electric Systems: A North Carolina Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource exists, how to choose the best site for a turbine, how to connect a system to the utility grid, and whether it's possible to become independent of the utility grid using wind energy. In addition, the cover of the guide contains a list of contacts for more information.

  4. Impact of wind generation on the operation and development of the UK electricity systems

    International Nuclear Information System (INIS)

    Strbac, Goran; Shakoor, Anser; Pudjianto, Danny; Black, Mary; Bopp, Thomas

    2007-01-01

    Although penetration of wind generation may displace a significant amount of energy produced by large conventional plant, there are issues associated with the extent to which wind generation will be able to replace the capacity and flexibility of conventional generating plant. This is important since wind power is variable, so it will be necessary to retain a significant proportion of conventional plant to ensure security of supply especially under conditions of high demand and low wind. Hence, the capacity value of wind generation will be limited as it will not be possible to displace conventional generation capacity on a ''megawatt for megawatt'' basis. Wind power is variable and not easy to predict, hence various forms of additional reserves will be needed to maintain the balance between supply and demand at all times. Additionally, if the majority of wind generation plant is located in Scotland and the North of England, reinforcement of the transmission network will be needed to accommodate the increases in the north-south flow of electricity. In this paper an assessment of the costs and benefits of wind generation on the UK electricity system is carried out, assuming different levels of wind power capacity. Overall, it is concluded that the system will be able to accommodate significant increases in wind power generation with relatively small increases in overall costs of supply, about 5% of the current domestic electricity price in case of 20% energy produced by wind power. (author)

  5. Influence of Rigid Body Motions on Rotor Induced Velocities and Aerodynamic Loads of a Floating Horizontal Axis Wind Turbine

    DEFF Research Database (Denmark)

    de Vaal, Jacobus B.; Hansen, Martin Otto Laver; Moan, Torgeir

    2014-01-01

    This paper discusses the influence of rigid body motions on rotor induced velocities and aerodynamic loads of a floating horizontal axis wind turbine. Analyses are performed with a simplified free wake vortex model specifically aimed at capturing the unsteady and non-uniform inflow typically......, and captures the essential influences of rigid body motions on the rotor loads, induced velocities and wake influence....... experienced by a floating wind turbine. After discussing the simplified model in detail, comparisons are made to a state of the art free wake vortex code, using test cases with prescribed platform motion. It is found that the simplified model compares favourably with a more advanced numerical model...

  6. A Wind Farm Electrical Systems Evaluation with EeFarm-II

    OpenAIRE

    Jan Pierik; Urban Axelsson; Emil Eriksson; Daniel Salomonsson; Pavol Bauer; Balazs Czech

    2010-01-01

    EeFarm-II is used to evaluate 13 different electrical systems for a 200 MW wind farm with a 100 km connection to shore. The evaluation is based on component manufacturer data of 2009. AC systems are compared to systems with DC connections inside the wind farm and DC connection to shore. Two options have the best performance for this wind farm size and distance: the AC system and the system with a DC connection to shore. EeFarm-II is a user friendly computer program for wind farm electrical an...

  7. Evaluation of a wind turbine electric power generator

    Science.gov (United States)

    Swim, W. B.

    1981-01-01

    A technical assessment of the aerodynamic performance of the wind wheel turbine (WWT) is reported. The potential of the WWT in utilizing wind as an alternate power source was evaluated. Scaling parameters were developed to predict the aerodynamic performance of WWT prototype sized to produce 3, 9, 30, and 100 kw outputs in a 6.7 m/sec wind.

  8. Integrating Wind Power in Electricity Grids : an Economic Analysis

    NARCIS (Netherlands)

    Liu, J.; Kooten, van G.C.; Pitt, L.

    2005-01-01

    As a renewable energy source, wind power is gaining popularity as a favoured alternative to fossil fuel, nuclear and hydro power generation. In Europe, countries are required to achieve 15% of their energy consumption from wind by 2010 as the EU strives to meet its Kyoto obligations. Wind power is

  9. Determination of recoverable wind energy for electricity generation ...

    African Journals Online (AJOL)

    Utilization of renewable energy source, essentially the wind energy, has been growing rapidly in the whole world due to environmental pollution, consumption of the limited fossil fuels and global warming. Moreover, wind resource determination is a fundamental step in planning a wind energy project and exhaustive ...

  10. Effect of wind turbine surge motion on rotor thrust and induced velocity

    DEFF Research Database (Denmark)

    Vaal, J.B., de; Hansen, Martin Otto Laver; Moan, T.

    2014-01-01

    velocity on a wind turbine rotor is investigated. Specifically, the performance of blade element momentum theory with a quasisteady wake as well as two widely used engineering dynamic inflow models is evaluated. A moving actuator disc model is used as reference, since the dynamics associated with the wake...... will be inherently included in the solution of the associated fluid dynamic problem. Through analysis of integrated rotor loads, induced velocities and aerodynamic damping, it is concluded that typical surge motions are sufficiently slow to not affect the wake dynamics predicted by engineering models significantly...

  11. The Darrieus wind turbine for electrical power generation

    Science.gov (United States)

    Robinson, M. L.

    1981-06-01

    Aspects of wind as an energy source and the momentum theory of wind turbines are briefly examined. Types of Darrieus wind turbine are described; attention is given to a turbine with airfoil blades curved in troposkein form, and a turbine with straight blades of fixed or variable pitch. The Darrieus vertical-axis wind turbine is then considered with regard to aerodynamics, annual energy output, structures, control systems, and energy storage. Brief reviews of selected Darrieus wind turbine projects are given, including those at Magdalen Islands, Canada, Sandia Laboratories, Reading University, and Australia and New Zealand.

  12. Electric utility application of wind energy conversion systems on the island of Oahu

    Energy Technology Data Exchange (ETDEWEB)

    Lindley, C.A.; Melton, W.C.

    1979-02-23

    This wind energy application study was performed by The Aerospace Corporation for the Wind Systems Branch of the Department of Energy. The objective was to identify integration problems for a Wind Energy Conversion System (WECS) placed into an existing conventional utility system. The integration problems included environmental, institutional and technical aspects as well as economic matters, but the emphasis was on the economics of wind energy. The Hawaiian Electric Company utility system on the island of Oahu was selected for the study because of the very real potential for wind energy on that island, and because of the simplicity afforded in analyzing that isolated utility.

  13. Short-Term Wind Electric Power Forecasting Using a Novel Multi-Stage Intelligent Algorithm

    Directory of Open Access Journals (Sweden)

    Haoran Zhao

    2018-03-01

    Full Text Available As the most efficient renewable energy source for generating electricity in a modern electricity network, wind power has the potential to realize sustainable energy supply. However, owing to its random and intermittent instincts, a high permeability of wind power into a power network demands accurate and effective wind energy prediction models. This study proposes a multi-stage intelligent algorithm for wind electric power prediction, which combines the Beveridge–Nelson (B-N decomposition approach, the Least Square Support Vector Machine (LSSVM, and a newly proposed intelligent optimization approach called the Grasshopper Optimization Algorithm (GOA. For data preprocessing, the B-N decomposition approach was employed to disintegrate the hourly wind electric power data into a deterministic trend, a cyclic term, and a random component. Then, the LSSVM optimized by the GOA (denoted GOA-LSSVM was applied to forecast the future 168 h of the deterministic trend, the cyclic term, and the stochastic component, respectively. Finally, the future hourly wind electric power values can be obtained by multiplying the forecasted values of these three trends. Through comparing the forecasting performance of this proposed method with the LSSVM, the LSSVM optimized by the Fruit-fly Optimization Algorithm (FOA-LSSVM, and the LSSVM optimized by Particle Swarm Optimization (PSO-LSSVM, it is verified that the established multi-stage approach is superior to other models and can increase the precision of wind electric power prediction effectively.

  14. A 'special effort' to provide improved sounding and cloud-motion wind data for FGGE. [First GARP Global Experiment

    Science.gov (United States)

    Greaves, J. R.; Dimego, G.; Smith, W. L.; Suomi, V. E.

    1979-01-01

    Enhancement and editing of high-density cloud motion wind assessments and research satellite soundings have been necessary to improve the quality of data used in The Global Weather Experiment. Editing operations are conducted by a man-computer interactive data access system. Editing will focus on such inputs as non-US satellite data, NOAA operational sounding and wind data sets, wind data from the Indian Ocean satellite, dropwindsonde data, and tropical mesoscale wind data. Improved techniques for deriving cloud heights and higher resolution sounding in meteorologically active areas are principal parts of the data enhancement program.

  15. Impacts from new 50 MW wind power plant - Bogdnaci on the price of electrical energy in Macedonia

    International Nuclear Information System (INIS)

    Minovski, D.; Sarac, V.; Causevski, A.

    2012-01-01

    The paper presents the impact from the new planned wind power plant Bogdnaci on the price for the end users of electrical energy in Republic of Macedonia. In the next years, 50 MW wind power will be installed in the Macedonian electric power system. Production of electricity from wind power plants is unpredictable and of stochastic nature i.e. depends on the weather or the wind speed at the appropriate locations. Output of wind power plants is changing every minute, thus changing in the hourly level can be from 0 - 100%, even several times depending on the occurrence of winds. Changes in output of wind power plants, leads to increased demand for operational reserve in a power system. Preferential price of electrical energy from the wind power plants and increased operational reserve in the electric power system will have big impact on the final price of electrical energy in Republic of Macedonia. (Authors)

  16. Influence of wind power, plug-in electric vehicles, and heat storages on power system investments

    DEFF Research Database (Denmark)

    Kiviluoma, Juha; Meibom, Peter

    2010-01-01

    electric vehicles. The model runs in an hourly time scale in order to accommodate the impact of variable power production from wind power. Electric vehicles store electricity for later use and can thus serve to increase the flexibility of the power system. Flexibility can also be upgraded by using heat......Due to rising fuel costs, the substantial price for CO2 emissions and decreasing wind power costs, wind power might become the least expensive source of power for an increasing number of power systems. This poses the questions of how wind power might change optimal investments in other forms...... of power production and what kind of means could be used to increase power system flexibility in order to incorporate the variable power production from wind power in a cost-effective manner. We have analysed possible effects using an investment model that combines heat and power production and simulates...

  17. Bubble Motion in Transformer Oil under Non-Uniform Electric Fields

    Science.gov (United States)

    Cai, Dan; Liu, Lie; Cheng, Guo-Xin; Zhang, Qiang; Zhao, Xue-Long; Zhao, Qi

    2013-03-01

    We investigate the bubble motion in transformer oil under a typical non-uniform electric field. Based on the principle of virtual work, an analytical equation is derived for the electric force putting on the bubbles. The bubble's visualized motion graphics are then obtained by using the finite-element method, which utilizes Comsol Multiphysics software. The effects of bubble radius and release position on the motion trajectory are studied. It is found that, under the non-uniform electric field, the bubbles have a long residence time between the electrodes. This accordingly can lead to a higher probability of forming a bubble-bridge along the bubble motion trajectory. The bubbles with a particular radius or release position are easier to form bubble-bridge between the electrodes. They can increase the chance of liquid breakdown.

  18. Presentation of a stochastic model estimating the wind energy contribution in remote island electrical networks

    International Nuclear Information System (INIS)

    Kaldellis, J.K.; Kapsali, M.; Tiligadas, D.

    2012-01-01

    Highlights: ► This study estimates the maximum wind energy contribution to an isolated micro-grid. ► An integrated computational tool is developed on the basis of stochastic analysis. ► The probability distribution of the wind energy surplus and deficit is estimated. ► The results indicate that a strict penetration limit is imposed to wind energy. -- Abstract: The electrification in remote islands whose electricity distribution network is not connected to the mainland’s grid is mostly based on Autonomous Power Stations (APSs) that are usually characterized by a considerably high electricity production cost, while at the same time the contribution of Renewable Energy Sources (RES) in these regions accounts for less than 10% of the total electricity generation. This actually results from the fact that despite the excellent wind potential of most of these islands, the wind energy contribution is significantly restricted from limits imposed to protect the remote electrical grids from possible instability problems, due to the stochastic wind speed behavior and the variable electricity consumption. On the basis of probability distribution of the load demand of a representative Greek island and the corresponding data related to the available wind potential, the present study estimates the maximum – acceptable by the local grid – wind energy contribution. For that reason, an integrated computational algorithm has been developed from first principles, based on a stochastic analysis. According to the results obtained, it becomes evident that with the current wind turbine technology, wind energy cannot play a key role in coping with the electrification problems encountered in many Greek island regions, excluding however the case of introducing bulk energy storage systems that may provide considerable recovery of the remarkable wind energy rejections expected.

  19. Electric Vehicles for Improved Operation of Power Systems with High Wind Power Penetration

    OpenAIRE

    Larsen, Esben; Chandrashekhara, Divya K; Østergaard, Jacob

    2008-01-01

    In a power system with a high share of wind energy the wind fluctuation causes a variation in the power generation, which must be compensated from other sources. The situation in Denmark with a penetration of more than 20% wind in yearly average is presented. The introduction of electric drive vehicles (EDV) as flexible loads can improve the system operation. Bidirectional power exchange through batteries (vehicle to grid) can be seen as a storage system in the grid. An analysis of possible e...

  20. Preliminary Investigation on Generation of Electricity Using Micro Wind Turbines Placed on A Car

    OpenAIRE

    Yogendra Chaudhary; Vijaya Bangi; Ramesh Guduru; Kendrick Aung; Ganesh Reddy

    2017-01-01

    Wind energy is one of the prominent resources for renewable energy and it is traditionally extracted using stationary wind turbines. However, it can also be extracted using mini or micro wind turbines on a moving body, such as an automobile, while cruising at high speeds on freeways. If the electricity is produced using air flowing around the vehicle without affecting aerodynamic performance of the vehicle, it can be used to charge up the battery or power up additional accessories of the vehi...

  1. How to improve the design of the electrical system in future wind power plants

    DEFF Research Database (Denmark)

    Arana Aristi, Iván; Holbøll, Joachim; Bak, C. L.

    2009-01-01

    is to improve the understanding of the main electrical components in wind farms, based on available information, measurement data and simulation tools. The aim of these projects is to obtain validated models of wind turbine (WT) generators, WT converters, WT transformers, submarine cables, circuit breakers...... and wind farm transformers, and to develop a methodology on how to select appropriate equipment for the power system, control system and protection system....

  2. Wind-powered electrical systems : highway rest areas, weigh stations, and team section buildings.

    Science.gov (United States)

    2009-02-01

    This project considered the use of wind for providing electrical power at Illinois Department of Transportation : (IDOT) highway rest areas, weigh stations, and team section buildings. The goal of the project was to determine : the extent to which wi...

  3. The UK electricity market and the wind industry - a perspective of 1998 proposals

    International Nuclear Information System (INIS)

    Batley, S.L.; Twidell, J.W.; Gibbons, C.

    1997-01-01

    After April 1st 1998, the Public Electricity Supplier monopoly ( in England, Wales and Scotland) over their local franchise market will cease and all customers, regardless of size, will be able to choose their supplier. These changes will have a major impact on the UK wind energy industry. An increased number of Second Tier Suppliers will compete with existing market players for electricity purchase from generators and sale of electricity to consumers. Market changes should improve possibilities for wind generators to obtain a Second Tier Supplier licence and serve the domestic, small demand, market. There may also be market opportunities to sell to specialist 'green' suppliers. The post 1998 changes are of importance to the European Union 'Guarantee of Result' project, which aims to promote small scale wind systems through guaranteed quality and performance of systems. For the Guarantee of Results to be utilised in the UK, all markets for the generated electricity from a wind system must be considered and evaluated. (Author)

  4. Power Electronic Drives, Controls, and Electric Generators for Large Wind Turbines - An Overview

    DEFF Research Database (Denmark)

    Ma, Ke; Tutelea, L.; Boldea, Ion

    2015-01-01

    of power electronics, ranging from devices to circuit topologies, and similar matters for electric generators, together with results of optimal design studies are included. It is shown that the individual power rating of wind turbines has increased over the years, and technologies required to reach......Wind represents a major and growing source of renewable energy for the electric power systems. This article provides an overview of state-of-the-art technologies and anticipated developments in the area of power electronic drives, controls, and electric generators for large multi-megawatt wind...... turbine systems. The principal components employed in a turbine for energy conversion from wind to electricity are described, and the main solutions that are commercially available are briefly reviewed. The specific issues of complex mission profiles, power codes, and reliability are discussed. Topics...

  5. 75 FR 27550 - Electrical Interconnection of the Juniper Canyon I Wind Project

    Science.gov (United States)

    2010-05-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Bonneville Power Administration Electrical Interconnection of the Juniper Canyon I Wind Project AGENCY: Bonneville Power Administration (BPA), Department of Energy (DOE). ACTION: Notice of Availability of Record...

  6. Influence of offshore wind farms layout on electrical resonances

    DEFF Research Database (Denmark)

    Holdyk, Andrzej; Holbøll, Joachim; Koldby, Erik

    2014-01-01

    , winding resistances and winding capacitances. Considering the frequency range of the present investigations, up to about 1 MHz, a lumped representation of the transformer characteristics was deemed sufficient. Breakers and capacitors are modelled as ideal components. The chosen wind farm layout includes...... ranges. The results show the influence of specific parameters being varied depending on the farm layout. In particular, cable lengths and transformer broad band characteristics turned out to have significant impact on the results....

  7. Understanding Power Electronics and Electrical Machines in Multidisciplinary Wind Energy Conversion System Courses

    Science.gov (United States)

    Duran, M. J.; Barrero, F.; Pozo-Ruz, A.; Guzman, F.; Fernandez, J.; Guzman, H.

    2013-01-01

    Wind energy conversion systems (WECS) nowadays offer an extremely wide range of topologies, including various different types of electrical generators and power converters. Wind energy is also an application of great interest to students and with a huge potential for engineering employment. Making WECS the main center of interest when teaching…

  8. Environmental Severity Classes for Main Electrical Components in Offshore Wind Turbine

    DEFF Research Database (Denmark)

    Henriksen, Matthew Lee; Koldby, Erik; Holbøll, Joachim

    2011-01-01

    This paper works toward a better understanding of how the environmental operating conditions for offshore wind turbine electrical components should be quantified. Different aspects of the operating environment are introduced and discussed, with reference to their relevance in offshore wind turbines...

  9. Application of genetic algorithm in electrical system optimization for offshore wind farms

    DEFF Research Database (Denmark)

    Chen, Zhe; Zhao, M.; Blaabjerg, Frede

    2008-01-01

    Genetic Algorithm (GA) has been widely used in solving optimization problem in different areas. This paper illustrates the application of GA in the electrical system design for offshore wind farms, where the main components of a wind farm and key technical specifications are used as input...

  10. Optimisation of electrical system for offshore wind farms via genetic algorithm

    DEFF Research Database (Denmark)

    Chen, Zhe; Zhao, Menghua; Blaabjerg, Frede

    2009-01-01

    An optimisation platform based on genetic algorithm (GA) is presented, where the main components of a wind farm and key technical specifications are used as input parameters and the electrical system design of the wind farm is optimised in terms of both production cost and system reliability...

  11. The Economics of Storage, Transmission and Drought: Integrating Variable Wind Power into Spatially Separated Electricity Grids

    NARCIS (Netherlands)

    Scora, H.; Sopinka, A.; Kooten, van G.C.

    2012-01-01

    To mitigate the high variability of wind and make it a more viable renewable energy source, observers recommend greater integration of spatially-separated electrical grids, with high transmission lines linking load centers, scattered wind farms and hydro storage sites. In this study, we examine the

  12. Fluid power network for centralized electricity generation in offshore wind farms

    NARCIS (Netherlands)

    Jarquin-Laguna, A.

    2014-01-01

    An innovative and completely different wind-energy conversion system is studied where a centralized electricity generation within a wind farm is proposed by means of a hydraulic network. This paper presents the dynamic interaction of two turbines when they are coupled to the same hydraulic network.

  13. Technical and commercial aspects of the connection of wind turbines to electricity supply networks in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, P. [Garrad Hassan & Partners Ltd., Glasgow (United Kingdom)

    1996-12-31

    This paper reviews some technical and commercial issues now topical for wind energy developments in Europe. The technical issues are important because of the weak nature of the existing electricity systems in rural or upland areas. Several commercial issues are considered which may improve the economics of wind energy as market incentives are gradually withdrawn. 9 refs.

  14. Roadmap of retail electricity market reform in China: assisting in mitigating wind energy curtailment

    Science.gov (United States)

    Yu, Dezhao; Qiu, Huadong; Yuan, Xiang; Li, Yuan; Shao, Changzheng; Lin, You; Ding, Yi

    2017-01-01

    Among the renewable energies, wind energy has gained the rapidest development in China. Moreover wind power generation has been penetrated into power system in a large scale. However, the high level wind curtailment also indicates a low efficiency of wind energy utilization over the last decade in China. One of the primary constraints on the utilization of wind energy is the lack of an electricity market, in which renewable energies can compete equally with traditional fossil fuel generation. Thus the new round electric power industry reform is essential in China. The reform involves implementing new pricing mechanism, introducing retail-side competition, promoting the consumption of renewable energy. The new round reform can be a promising solution for promoting the development and consumption of wind energy generation in China. Based on proposed reform policies of electric power industry, this paper suggests a roadmap for retail electricity market reform of China, which consists of three stages. Barriers to the efficient utilization of wind energy are also analysed. Finally, this paper introduces several efficient measures for mitigating wind curtailment in each stage of reform.

  15. A Wind Farm Electrical Systems Evaluation with EeFarm-II

    NARCIS (Netherlands)

    Pierik, J.; Axelsson, U.; Eriksson, E.; Salomonsson, D.; Bauer, P.; Czech, B.

    2010-01-01

    EeFarm-II is used to evaluate 13 different electrical systems for a 200 MW wind farm with a 100 km connection to shore. The evaluation is based on component manufacturer data of 2009. AC systems are compared to systems with DC connections inside the wind farm and DC connection to shore. Two options

  16. Effect of blade flutter and electrical loading on small wind turbine noise

    Science.gov (United States)

    The effect of blade flutter and electrical loading on the noise level of two different size wind turbines was investigated at the Conservation and Production Research Laboratory (CPRL) near Bushland, TX. Noise and performance data were collected on two blade designs tested on a wind turbine rated a...

  17. Electric Generators Fitted to Wind Turbine Systems: An Up-to-Date Comparative Study

    OpenAIRE

    Lebsir, A; Bentounsi, A; Benbouzid, Mohamed; Mangel, H

    2015-01-01

    International audience; This paper describes a comparative study allowing the selection of the most appropriate innovative structures for electrical machines for a wind turbine system. This study is based on an exhaustive review of the state of the art and on an effective comparison of the performances of the three main conventional electric generator in wind energy application system that are the Doubly-Fed Induction Generator (DFIG), the Squirrel-Cage Induction Generator (SCIG), the Permane...

  18. Public and private attitudes towards 'green' electricity: the case of Swedish wind power

    International Nuclear Information System (INIS)

    Ek, Kristina

    2005-01-01

    There exists a political goal in Sweden and elsewhere to increase the use of renewable energy and wind power seems to be a favourable choice from an environmental perspective. However, although the public generally expresses a positive attitude towards wind power, the experience often shows that specific wind power projects face resistance from the local population. This paper analyses the attitudes towards wind power among the electricity consumers as well as the foundations of these attitudes. Results are based on a postal survey that was sent out to 1000 Swedish house owners. According to the results, the public is generally positive towards wind power. The probability of finding an average individual in support of wind power decreases with age and income. People with an interest in environmental issues are, however, more likely to be positive towards wind power than the average respondent and the results do not support the NIMBY-hypothesis. In addition, people that are more inclined to express public preferences are also more likely to be positive towards wind electricity than people who are less inclined to do so. These results imply, for instance, that the potential of markets for 'green' electricity may be limited, other support schemes is thus required if the politically stated goal to increase wind power capacity is to be fulfilled

  19. Short-term optimal wind power generation capacity in liberalized electricity markets

    International Nuclear Information System (INIS)

    Olsina, Fernando; Roescher, Mark; Larisson, Carlos; Garces, Francisco

    2007-01-01

    Mainly because of environmental concerns and fuel price uncertainties, considerable amounts of wind-based generation capacity are being added to some deregulated power systems. The rapid wind development registered in some countries has essentially been driven by strong subsidizing programs. Since wind investments are commonly isolated from market signals, installed wind capacity can be higher than optimal, leading to distortions of the power prices with a consequent loss of social welfare. In this work, the influence of wind generation on power prices in the framework of a liberalized electricity market has been assessed by means of stochastic simulation techniques. The developed methodology allows investigating the maximal wind capacity that would be profitably deployed if wind investments were subject to market conditions only. For this purpose, stochastic variables determining power prices are accurately modeled. A test system resembling the size and characteristics of the German power system has been selected for this study. The expected value of the optimal, short-term wind capacity is evaluated for a considerable number of random realizations of power prices. The impact of dispersing the wind capacity over statistical independent wind sites has also been evaluated. The simulation results reveal that fuel prices, installation and financing costs of wind investments are very influential parameters on the maximal wind capacity that might be accommodated in a market-based manner

  20. Wind Power in Ontario: Its Contribution to the Electricity Grid

    Science.gov (United States)

    Rowlands, Ian H.; Jernigan, Carey

    2008-01-01

    The purpose of this article is to investigate wind turbine production, the variability of that production, and the relationship between output and system-wide demand. A review of the literature reveals that a variety of measures (and methods) to explore the variability of wind power production exist. Attention then turns to the province of Ontario…

  1. Wind energy, electricity, and hydrogen in the Netherlands

    NARCIS (Netherlands)

    Schenk, Niels J.; Moll, Henri C.; Potting, José; Benders, René M.J.

    2007-01-01

    The curbing of greenhouse gases (GHG) is an important issue on the international political agenda. The substitution of fossil fuels by renewable energy sources is an often-advocated mitigation strategy. Wind energy is a potential renewable energy source. However, wind energy is not reliable since

  2. Statistical analysis of wind speed for electrical power generation in ...

    African Journals Online (AJOL)

    Also, the results have shown that Jos, Kano and Minna fall in class 4 and therefore suitable for both off grid and grid connected modes. In addition, the effects of c and k parameters on the probability distribution functions have been presented. Keywords: Wind speed - probability - density function – wind energy conversion ...

  3. Device for delivering cryogen to rotary super-conducting winding of cryogen-cooled electrical machine

    International Nuclear Information System (INIS)

    Filippov, I.F.; Gorbunov, G.S.; Khutoretsky, G.M.; Popov, J.S.; Skachkov, J.V.; Vinokurov, A.A.

    1980-01-01

    A device is disclosed for delivering cryogen to a superconducting winding of a cryogen-cooled electrical machine comprising a pipe articulated along the axis of the electrical machine and intended to deliver cryogen. One end of said pipe is located in a rotary chamber which communicates through channels with the space of the electrical machine, and said space accommodating its superconducting winding. The said chamber accommodates a needle installed along the chamber axis, and the length of said needle is of sufficient length such that in the advanced position of said cryogen delivering pipe said needle reaches the end of the pipe. The layout of the electrical machine increases the reliability and effectiveness of the device for delivering cryogen to the superconducting winding, simplifies the design of the device and raises the efficiency of the electrical machine

  4. Assessing the value of wind generation in future carbon constrained electricity industries

    International Nuclear Information System (INIS)

    Vithayasrichareon, Peerapat; MacGill, Iain F.

    2013-01-01

    This paper employs a novel Monte-Carlo based generation portfolio assessment tool to explore the implications of increasing wind penetration and carbon prices within future electricity generation portfolios under considerable uncertainty. This tool combines optimal generation mix techniques with Monte Carlo simulation and portfolio analysis methods to determine expected overall generation costs, associated cost uncertainty and expected CO 2 emissions for different possible generation portfolios. A case study of an electricity industry with coal, Combined Cycle Gas Turbines (CCGT), Open Cycle Gas Turbines (OCGT) and wind generation options that faces uncertain future fossil-fuel prices, carbon pricing, electricity demand and plant construction costs is presented to illustrate some of the key issues associated with growing wind penetrations. The case study uses half-hourly demand and wind generation data from South Eastern Australia, and regional estimates of new-build plant costs and characteristics. Results suggest that although wind generation generally increases overall industry costs, it reduces associated cost uncertainties and CO 2 emissions. However, there are some cases in which wind generation can reduce the overall costs of generation portfolios. The extent to which wind penetration affects industry expected costs and uncertainties depends on the level of carbon price and the conventional technology mix in the portfolios. - Highlights: ► A probabilistic portfolio analysis tool to assess generation portfolios with wind power. ► Explore the impacts of wind penetrations and carbon prices under uncertainties. ► Wind generation increases overall portfolio costs but reduces cost risks and emissions. ► The value of wind power depends on the carbon price and the technology mix. ► Complex interactions between wind penetration level and carbon pricing.

  5. Electricity network limitations on large-scale deployment of wind energy

    Energy Technology Data Exchange (ETDEWEB)

    Fairbairn, R.J.

    1999-07-01

    This report sought to identify limitation on large scale deployment of wind energy in the UK. A description of the existing electricity supply system in England, Scotland and Wales is given, and operational aspects of the integrated electricity networks, licence conditions, types of wind turbine generators, and the scope for deployment of wind energy in the UK are addressed. A review of technical limitations and technical criteria stipulated by the Distribution and Grid Codes, the effects of system losses, and commercial issues are examined. Potential solutions to technical limitations are proposed, and recommendations are outlined.

  6. Optimal grid design and logistic planning for wind and biomass based renewable electricity supply chains under uncertainties

    International Nuclear Information System (INIS)

    Osmani, Atif; Zhang, Jun

    2014-01-01

    In this work, the grid design and optimal allocation of wind and biomass resources for renewable electricity supply chains under uncertainties is studied. Due to wind intermittency, generation of wind electricity is not uniform and cannot be counted on to be readily available to meet the demand. Biomass represents a type of stored energy and is the only renewable resource that can be used for producing biofuels and generating electricity whenever required. However, amount of biomass resources are finite and might not be sufficient to meet the demand for electricity and biofuels. Potential of wind and biomass resources is therefore jointly analyzed for electricity generation. Policies are proposed and evaluated for optimal allocation of finite biomass resources for electricity generation. A stochastic programming model is proposed that optimally balances the electricity demand across the available supply from wind and biomass resources under uncertainties in wind speed and electricity sale price. A case study set in the American Midwest is presented to demonstrate the effectiveness of the proposed model by determining the optimal decisions for generation and transmission of renewable electricity. Sensitivity analysis shows that level of subsidy for renewable electricity production has a major impact on the decisions. - Highlights: • Stochastic optimization model for wind/biomass renewable electricity supply chain. • Multiple uncertainties in wind speeds and electricity sale price. • Proposed stochastic model outperforms the deterministic model under uncertainties. • Uncertainty affects grid connectivity and allocation of power generation capacity. • Location of wind farms is found to be insensitive to the stochastic environment

  7. An parametric investigation into the effect of low induction rotor (LIR) wind turbines on the levelised cost of electricity of a 1 GW offshore wind farm in a North Sea wind climate

    NARCIS (Netherlands)

    R. Quinn; B. Bulder; Gerard Schepers

    In this report, the details of an investigation into the eect of the low induction wind turbines on the Levelised Cost of Electricity (LCoE) in a 1GW oshore wind farm is outlined. The 10 MW INNWIND.EU conventional wind turbine and its low induction variant, the 10 MW AVATAR wind turbine, are

  8. Contrasting electricity demand with wind power supply: case study in Hungary

    International Nuclear Information System (INIS)

    Kiss, P.; Janosi, I. M.; Varga, L.

    2009-01-01

    We compare the demand of a large electricity consumer with supply given by wind farms installed at two distant geographic locations. Obviously such situation is rather unrealistic, however our main goal is a quantitative characterization of the intermittency of wind electricity. The consumption pattern consists of marked daily and weekly cycles interrupted by periods of holidays. In contrast, wind electricity production has neither short-time nor seasonal periodicities. We show that wind power integration over a restricted area cannot provide a stable base load supply, independently of the excess capacity. Further essential result is that the statistics are almost identical for a weekly periodic pattern of consumption and a constant load of the same average value. The length of both adequate supply and shortfall intervals exhibits a scale-free (power-law) frequency distribution, possible consequences are shortly discussed. (author)

  9. Contrasting Electricity Demand with Wind Power Supply: Case Study in Hungary

    Directory of Open Access Journals (Sweden)

    Imre M. Jánosi

    2009-09-01

    Full Text Available We compare the demand of a large electricity consumer with supply given by wind farms installed at two distant geographic locations. Obviously such situation is rather unrealistic, however our main goal is a quantitative characterization of the intermittency of wind electricity. The consumption pattern consists of marked daily and weekly cycles interrupted by periods of holidays. In contrast, wind electricity production has neither short-time nor seasonal periodicities. We show that wind power integration over a restricted area cannot provide a stable baseload supply, independently of the excess capacity. Further essential result is that the statistics are almost identical for a weekly periodic pattern of consumption and a constant load of the same average value. The length of both adequate supply and shortfall intervals exhibits a scale-free (power-law frequency distribution, possible consequences are shortly discussed.

  10. What day-ahead reserves are needed in electric grids with high levels of wind power?

    International Nuclear Information System (INIS)

    Mauch, Brandon; Apt, Jay; Jaramillo, Paulina; Carvalho, Pedro M S

    2013-01-01

    Day-ahead load and wind power forecasts provide useful information for operational decision making, but they are imperfect and forecast errors must be offset with operational reserves and balancing of (real time) energy. Procurement of these reserves is of great operational and financial importance in integrating large-scale wind power. We present a probabilistic method to determine net load forecast uncertainty for day-ahead wind and load forecasts. Our analysis uses data from two different electric grids in the US with similar levels of installed wind capacity but with large differences in wind and load forecast accuracy, due to geographic characteristics. We demonstrate that the day-ahead capacity requirements can be computed based on forecasts of wind and load. For 95% day-ahead reliability, this required capacity ranges from 2100 to 5700 MW for ERCOT, and 1900 to 4500 MW for MISO (with 10 GW of installed wind capacity), depending on the wind and load forecast values. We also show that for each MW of additional wind power capacity for ERCOT, 0.16–0.30 MW of dispatchable capacity will be used to compensate for wind uncertainty based on day-ahead forecasts. For MISO (with its more accurate forecasts), the requirement is 0.07–0.13 MW of dispatchable capacity for each MW of additional wind capacity. (letter)

  11. What's Powering Wind? Measuring the Environmental Benefits of Wind Generated Electricity

    OpenAIRE

    Cullen, Joseph

    2008-01-01

    Production subsidies for renewable energy have experienced intermittent support from the federal government. One reason for less than united support arises from uncertainty over the environmental impact of projects implemented because of such subsidies. Wind energy in particular has taken advantage of federal subsidies, but what has been the environmental impact? Taking investment in wind capacity as given, I am able to identify the short run substitution patterns between wind power and conve...

  12. European Short-term Electricity Market Designs under High Penetration of Wind Power

    NARCIS (Netherlands)

    Chaves Avila, J.P.

    2014-01-01

    The EU has ambitious policies for decarbonization of the electricity sector. Due to recent technological developments, wind power already represents a significant share of the generation mix in some European countries. As a result, short-term electricity markets and balancing arrangements must be

  13. The electric wind of Venus: A global and persistent "polar wind"-like ambipolar electric field sufficient for the direct escape of heavy ionospheric ions

    Science.gov (United States)

    Collinson, Glyn A.; Frahm, Rudy A.; Glocer, Alex; Coates, Andrew J.; Grebowsky, Joseph M.; Barabash, Stas; Domagal-Goldman, Shawn D.; Fedorov, Andrei; Futaana, Yoshifumi; Gilbert, Lin K.; Khazanov, George; Nordheim, Tom A.; Mitchell, David; Moore, Thomas E.; Peterson, William K.; Winningham, John D.; Zhang, Tielong L.

    2016-06-01

    Understanding what processes govern atmospheric escape and the loss of planetary water is of paramount importance for understanding how life in the universe can exist. One mechanism thought to be important at all planets is an "ambipolar" electric field that helps ions overcome gravity. We report the discovery and first quantitative extraterrestrial measurements of such a field at the planet Venus. Unexpectedly, despite comparable gravity, we show the field to be five times stronger than in Earth's similar ionosphere. Contrary to our understanding, Venus would still lose heavy ions (including oxygen and all water-group species) to space, even if there were no stripping by the solar wind. We therefore find that it is possible for planets to lose heavy ions to space entirely through electric forces in their ionospheres and such an "electric wind" must be considered when studying the evolution and potential habitability of any planet in any star system.

  14. The Electric Wind of Venus: A global and persistent "polar wind" like ambipolar electric field sufficient for the direct escape of heavy ionospheric ions

    Science.gov (United States)

    Collinson, G.; Frahm, R.; Glocer, A.; Coates, A. J.; Grebowsky, J. M.; Barbash, S.; Fedorov, A.; Futaana, Y.; Gilbert, L.; Khazanov, G. V.; Domagal-Goldman, S. D.; Nordheim, T.; Mitchell, D. L.; Moore, T. E.; Peterson, W.; Winningham, D.; Zhang, T.

    2016-12-01

    Understanding what processes govern atmospheric escape and the loss of planetary water is of paramount importance for understanding how life in the universe can exist. One mechanism thought to be important at all planets is an "ambipolar" electric field that helps ions overcome gravity. We report the discovery and first quantitative extraterrestrial measurements of such a field at the planet Venus. Unexpectedly, despite comparable gravity, we show the field to be five times stronger than in Earth's similar ionosphere. Contrary to our understanding, Venus would still lose heavy ions (including oxygen and all water-group species) to space, even if there were no stripping by the solar wind. We therefore find it is possible for planets to lose heavy ions to space entirely through electric forces in their ionospheres, and such an "electric wind" must be considered when studying the evolution and potential habitability of any planet in any star system

  15. The Electric Wind of Venus: A Global and Persistent Polar Wind -Like Ambipolar Electric Field Sufficient for the Direct Escape of Heavy Ionospheric Ions

    Science.gov (United States)

    Collinson, Glyn A.; Frahm, Rudy A.; Glocer, Alex; Coates, Andrew J.; Grebowsky, Joseph M.; Barabash, Stas; Domagal-Goldman, Shawn D.; Federov, Andrei; Futaana, Yoshifumi; Gilbert, Lin K.; hide

    2016-01-01

    Understanding what processes govern atmospheric escape and the loss of planetary water is of paramount importance for understanding how life in the universe can exist. One mechanism thought to be important at all planets is an ambipolar electric field that helps ions overcome gravity. We report the discovery and first quantitative extraterrestrial measurements of such a field at the planet Venus. Unexpectedly, despite comparable gravity, we show the field to be five times stronger than in Earths similar ionosphere. Contrary to our understanding, Venus would still lose heavy ions (including oxygen and all water-group species) to space, even if there were no stripping by the solar wind. We therefore find that it is possible for planets to lose heavy ions to space entirely through electric forces in their ionospheres and such an electric wind must be considered when studying the evolution and potential habitability of any planet in any star system.

  16. Optimization of Electrical System for a Large DC Offshore Wind Farm by Genetic Algorithm

    DEFF Research Database (Denmark)

    Zhao, Menghua; Chen, Zhe; Blaabjerg, Frede

    2004-01-01

    This paper proposes an optimization platform based on Genetic Algorithm, where the main components of the electrical system of a wind farm and key technical specifications are used as input parameters and the topology of the electrical system is to be optimized for a minimum cost and high...... reliability. A method to encode and decode an electrical system is studied. The reliability evaluation for a given network is also investigated. Genetic Algorithm is implemented to find the optimum network design for a large DC wind farm. It is concluded that different topologies may cause very different cost...... and reliability, and the Genetic Algorithm is capable of finding the optimum solution....

  17. Electricity from Wind for Off-Grid Applications in Bangladesh: A Techno-Economic Assessment

    Directory of Open Access Journals (Sweden)

    Md. Mustafizur Rahman

    2017-03-01

      Keywords: GHG emission, cost of electricity, off-grid, wind energy, electricity generation. Article History: Received October 15th 2016; Received in revised form January 26th 2017; Accepted February 4th 2017; Available online How to Cite This Article: Rahman, M.M., Baky, M.A.H, and Islam, A.K.M.S. (2017 Electricity from Wind for Off-Grid Applications in Bangladesh: A Techno-Economic Assessment. International Journal of Renewable Energy Develeopment, 6(1, 55-64. http://dx.doi.org/10.14710/ijred.6.1.55-64

  18. Voltage Sags Ride-Through of Motion Sensorless Controlled PMSG for Wind Turbines

    DEFF Research Database (Denmark)

    Fatu, Marius; Lascu, Cristian; Andreescu, Gheorghe-Daniel

    2007-01-01

    . The control system employs PI current controllers with crosscoupling decoupling for both inverters, an active power controller, and a DC link voltage controller. The PMSG rotor speed without using emf integration, and the line voltage frequency are estimated by two PLL based observers. A Dmodule filter...... with experimental results for single-, two-, and three-phase voltage source sags. Smooth transition through asymmetric voltage sags is demonstrated by all experiments.......This paper describes a variable-speed motion-sensorless permanent magnet synchronous generator (PMSG) control system for wind energy generation. The proposed system contains a PMSG connected to the grid by a back-to-back PWM inverter with bidirectional power flow, a line filter, and a transformer...

  19. Stochastic Optimal Regulation Service Strategy for a Wind Farm Participating in the Electricity Market

    DEFF Research Database (Denmark)

    Zhang, Baohua; Hu, Weihao; Chen, Zhe

    2015-01-01

    in the stochastic optimization to deal with the uncertainty of the up regulation price and the up regulation activation of the power system.The Danish short-term electricity market and a wind farm in western Denmark are chosen to evaluate the effect of the proposed strategy. Simulation results showthe proposed......As modern wind farmshave the ability to provideregulation service for the power system, wind power plant operators may be motivated to participate in the regulating market to maximize their profit.In this paper, anoptimal regulation servicestrategy for a wind farm to participate...... in the regulatingmarket is proposed. The relationship between up regulation price and wind power level,and the relationship between the probability of up regulation and the wind power level are studied. Thestochastic optimizationis adopted to find the optimal ratiofor regulation service. The Monte Carlo method is used...

  20. Optimization of Electrical System for Offshore Wind Farms via a Genetic Algorithm Approach

    DEFF Research Database (Denmark)

    Zhao, Menghua

    Offshore wind farms seem to be more attractive than onshore farms. However, offshore wind farms cost more money than onshore wind farms in both installation and maintenance. Due to the fast development of power electronics, more kinds of configurations of offshore wind farm are possible, which lead...... to very different costs, system reliability, power quality, and power losses etc. Therefore, the optimization of electrical system design for offshore wind farms becomes more and more necessary. There are two tasks in this project: 1) the first one is to construct an algorithm for finding the capacity......, and the LTC limitation of transformers, the power generation limits and the voltage operation range are considered as the constraints. The optimization method combined with probabilistic analysis is used to obtain the capacity of a given wind farm site. The OES-OWF is approached by Genetic Algorithm (GA...

  1. Electrical Power Grid Delivery Dynamic Analysis: Using Prime Mover Engines to Balance Dynamic Wind Turbine Output

    Energy Technology Data Exchange (ETDEWEB)

    Diana K. Grauer; Michael E. Reed

    2011-11-01

    This paper presents an investigation into integrated wind + combustion engine high penetration electrical generation systems. Renewable generation systems are now a reality of electrical transmission. Unfortunately, many of these renewable energy supplies are stochastic and highly dynamic. Conversely, the existing national grid has been designed for steady state operation. The research team has developed an algorithm to investigate the feasibility and relative capability of a reciprocating internal combustion engine to directly integrate with wind generation in a tightly coupled Hybrid Energy System. Utilizing the Idaho National Laboratory developed Phoenix Model Integration Platform, the research team has coupled demand data with wind turbine generation data and the Aspen Custom Modeler reciprocating engine electrical generator model to investigate the capability of reciprocating engine electrical generation to balance stochastic renewable energy.

  2. Interplanetary and Interstellar Dust Observed by the Wind/WAVES Electric Field Instrument

    Science.gov (United States)

    Malaspina, David; Horanyi, M.; Zaslavsky, A.; Goetz, K.; Wilson, L. B., III; Kersten, K.

    2014-01-01

    Observations of hypervelocity dust particles impacting the Wind spacecraft are reported here for the first time using data from the WindWAVES electric field instrument. A unique combination of rotating spacecraft, amplitude-triggered high-cadence waveform collection, and electric field antenna configuration allow the first direct determination of dust impact direction by any spacecraft using electric field data. Dust flux and impact direction data indicate that the observed dust is approximately micron-sized with both interplanetary and interstellar populations. Nanometer radius dust is not detected by Wind during times when nanometer dust is observed on the STEREO spacecraft and both spacecraft are in close proximity. Determined impact directions suggest that interplanetary dust detected by electric field instruments at 1 AU is dominated by particles on bound trajectories crossing Earths orbit, rather than dust with hyperbolic orbits.

  3. Policy instruments for regulating the development of wind power in a liberated electricity market

    International Nuclear Information System (INIS)

    Morthorst, P.E.

    1999-01-01

    Wind power is facing the dual challenge of entering a liberated electricity market and at the same time being one of the main contributors to the reduction of greenhouse gas emissions. The paper analyses the importance of the existing standard payment schemes in the development of wind power, and how this might be affected by the introduction of a liberated electricity market. The existing Danish standard payment scheme has strongly encouraged investments in wind turbines. It has been and still is very effective in promoting a high wind power capacity development, but at a high economic cost to the Danish Government. Different models of conditions for wind power at an electricity exchange do exist, but all seem to introduce a higher risk to the individual wind turbine owner than seen with the present payment scheme. In short it might be stated that going from the existing standard payment system to a market based system, the political uncertainty is converted to a market risk for the individual wind turbine owner. (au)

  4. Policy instruments for regulating the development of wind power in a liberated electricity market

    Energy Technology Data Exchange (ETDEWEB)

    Morthorst, P.E. [Risoe National Lab., Roskilde (Denmark)

    1999-03-01

    Wind power is facing the dual challenge of entering a liberated electricity market and at the same time being one of the main contributors to the reduction of greenhouse gas emissions. The paper analyses the importance of the existing standard payment schemes in the development of wind power, and how this might be affected by the introduction of a liberated electricity market. The existing Danish standard payment scheme has strongly encouraged investments in wind turbines. It has been and still is very effective in promoting a high wind power capacity development, but at a high economic cost to the Danish Government. Different models of conditions for wind power at an electricity exchange do exist, but all seem to introduce a higher risk to the individual wind turbine owner than seen with the present payment scheme. In short it might be stated that going from the existing standard payment system to a market based system, the political uncertainty is converted to a market risk for the individual wind turbine owner. (au)

  5. Carbon price instead of support schemes: wind power investments by the electricity market

    International Nuclear Information System (INIS)

    Petitet, Marie; Finon, Dominique; Janssen, Tanguy

    2014-10-01

    In this paper we study the development of wind power by the electricity market without any usual support scheme which is aimed at subsidizing non mature renewables, with the sole incentive of a significant carbon price. Long term electricity market and investment decisions simulation by system dynamics modelling is used to trace the electricity generation mix evolution over a 20-year period in a pure thermal system. A range of stable carbon price, as a tax could be, is tested in order to determine the value above which wind power development by market forces becomes economically possible. Not only economic competitiveness in terms of cost price, but also profitability against traditional fossil fuel technologies are necessary for a market-driven development of wind power. Results stress that wind power is really profitable for investors only if the carbon price is very significantly higher than the price required for making wind power MWh's cost price competitive with CCGT and coal-fired plants on the simplistic basis of levelized costs. In this context, the market-driven development of wind power seems only possible if there is a strong commitment to climate policy, reflected by the preference for a stable and high carbon price rather than a fuzzy price of an emission trading scheme. Besides, results show that market-driven development of wind power would require a sky-rocketing carbon price if the initial technology mix includes a share of nuclear plants even with a moratorium on new nuclear development. (authors)

  6. Technologies for production of electricity and heat in Sweden. Wind energy in perspective of international development

    Energy Technology Data Exchange (ETDEWEB)

    Clausen, Niels-Erik; Lawaetz, Henrik; Lemming, Joergen; Morthorst, Poul Erik

    2008-12-15

    The development of the wind energy technology has been very successful from the 1970s and up till now. Initially there was a battle between wind turbine concepts, but the commercial winner today is the three-bladed horizontal axis, upwind, electricity producing and grid connected wind turbine with availability on mature markets somewhere around 99%. An important contributor to the growth of the European market for wind energy technology has been EU framework legislation combined with legislation at the national level. The binding target for renewable energy in Sweden is proposed to be 49% of the final energy consumption in 2020 compared to 39.8% in 2005. To stimulate the development of wind energy and to promote a specific national goals Sweden is mainly using an electricity certificate system. The target is to increase the production of electricity from renewable sources by 17 TWh in 2016, relative to corresponding production in 2002. There is not at specific target for the use of wind energy. A future energy system that includes a high proportion of wind energy will be expected to meet the same requirements for security of supply and economic efficiency as the energy systems of today. The variability of wind power create a specific challenges for the future energy systems compared to those of today. The economics of wind power depends mainly of investment cost, operation and maintenance costs, electricity production and turbine lifetime. An average turbine installed in Europe has a total investment cost of 1.230 Euro/kW with a typically variation from approximately 1000 Euro/kW to approximately 1400 Euro/kW. The calculated costs per kWh wind generated power range from approximately 7-10 cEuro/kWh at sites with low average wind speeds to approximately 5-6.5 cEuro/kWh at good coastal positions, with an average of approximately 7cEuro/kWh at a medium wind site. Offshore costs are largely dependent on weather and wave conditions, water depth, and distance to the

  7. Unit commitment and system reliability in electric utility systems with independent wind and solar generation

    Science.gov (United States)

    Schooley, David Christopher

    Concerns about the environmental impacts of fossil fuels and changes in government regulations concerning electric utilities are likely to lead to increased use of wind and solar energy in the generation mix. In many cases, the wind and solar energy conversion systems will be owned by small, independent power producers that sell power to electric utilities. The output of wind and solar energy conversion systems is highly random; therefore, a method is necessary to determine the effects of these sources on the system reliability. This dissertation discusses a method of integrating the behavior of small power producing facilities (SPPFS) into the generation mix. The research method integrates models of wind and solar energy conversion systems with a model of the small power producers. The SPPF model is then integrated into the electric utility unit commitment procedure. System reliability indices such as the loss of load expectation (LOLE ) and the expected unserved energy (EUE) can be calculated once the SPPFs have been integrated into the generation mix. This dissertation demonstrates the procedure and provides results for a large electric utility with SPPFS located in Atlanta, Georgia; Bismark, North Dakota; and Oklahoma City, Oklahoma. Various combinations of wind and/or solar energy conversion systems are studied. The results include comparisons of the effective utilization of the wind and solar energy conversion systems at the different sites and of the effects on the system reliability.

  8. Integrating wind power in EU electricity systems. Economic and technical issues

    International Nuclear Information System (INIS)

    Van Werven, M.J.N.; Beurskens, L.W.M.; Pierik, J.T.G.

    2005-02-01

    In view of the ongoing process of liberalisation of the electricity market and the expected increase of wind power pursuant the RES-E Directive (Renewable Energy Sources - Electricity) and the need to minimise the costs of the RES-E targets, this study discusses the technical and economic impacts of integrating wind power into the electricity system. Furthermore, two options for reducing costs of intermittency are researched: forecasting of wind power output and electricity storage. An increasing penetration of wind power into the electricity system causes additional costs, partly due to the fact that the energy source of wind power is uncontrollable, variable (on the short term as well as on the longer term), and unpredictable (especially on the longer term). Consequently, balancing generation and demand becomes more complicated, creating a need for additional secondary and tertiary control. Although the sources of increasing costs are becoming more clearly understood, as are means to mitigate them, the quantification of costs of operating an electricity system with high wind penetration is very hard. Two possible options to reduce costs of intermittency are discussed in this report: forecasting of wind power output and electricity storage. The need for and benefit of wind energy forecasting have been increasingly recognised in recent years. Forecasting of wind power directs on increasing the predictability of the resource and improved forecasting can help to enhance the balancing of supply and demand. DG (distributed generation) operators can provide better information about their expected power output, energy suppliers can submit better estimates of electricity production to the TSO (Transmission System Operator), and system operators can improve network management through better information about expected power flows. Electricity storage systems can, at the same time, offer different services to a number of actors. Next to benefits that result from price

  9. Impact of Public Aggregate Wind Forecasts on Electricity Market Outcomes

    DEFF Research Database (Denmark)

    Exizidis, Lazaros; Kazempour, Jalal; Pinson, Pierre

    2017-01-01

    Following a call to foster a transparent and more competitive market, member states of the European transmission system operator are required to publish, among other information, aggregate wind power forecasts. The publication of the latter information is expected to benefit market participants...... by offering better knowledge of the market operation, leading subsequently to a more competitive energy market. Driven by the above regulation, we consider an equilibrium study to address how public information of aggregate wind power forecasts can potentially affect market results, social welfare as well...... as the profits of participating power producers. We investigate, therefore, a joint day-ahead energy and reserve auction, where producers offer their conventional power strategically based on a complementarity approach and their wind power at generation cost based on a forecast. In parallel, an iterative game...

  10. Technologies for production of Electricity and Heat in Sweden. Wind energy in perspective of international development

    DEFF Research Database (Denmark)

    Clausen, Niels-Erik; Lawaetz, Henrik; Lemming, Jørgen Kjærgaard

    with availability on mature markets somewhere around 99%. An important contributor to the growth of the European market for wind energy technology has been EU framework legislation combined with legislation at the national level. The binding target for renewable energy in Sweden is proposed to be 49% of the final...... energy consumption in 2020 compared to 39.8% in 2005. To stimulate the development of wind energy and to promote a specific national goals Sweden is mainly using an electricity certificate system. The target is to increase the production of electricity from renewable sources by 17 TWh in 2016, relative...... to corresponding production in 2002. There is not at specific target for the use of wind energy. A future energy system that includes a high proportion of wind energy will be expected to meet the same requirements for security of supply and economic efficiency as the energy systems of today. The variability...

  11. Partial analysis of wind power limit in an electric micro system using continuation power flow

    International Nuclear Information System (INIS)

    Fiallo Guerrero, Jandry; Santos Fuentefria, Ariel; Castro Fernández, Miguel

    2013-01-01

    The wind power insertion in the power system is an important issue and can create some instability problems in voltage and system frequency due to stochastic origin of wind. Know the Wind Power Limit that can insert in an electric grid without losing stability is a very important matter. Existing in bibliography a few methods for calculation of wind power limit, some of them are based in static constrains, an example is a method based in a continuation power flow analysis. In the present work the method is applied in an electric micro system formed when the system is disconnected of the man grid, the main goal was prove the method in a weak and island network. The software used in the simulations was the Power System Analysis Toolbox (PSAT). (author)

  12. Electric Vehicle Based Battery Storages for Large Scale Wind Power Integration in Denmark

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna

    . In Denmark, there are many hours of surplus wind power production every year. This could be consumed locally through demand side management of electric vehicles by controlled charging of their batteries. Also, the EV batteries could discharge the stored electricity to the grid on demand, which...... is improving on a rapid scale and the battery cost is also reducing which could enable the electric cars to be competitive in the market. The electric vehicles could also benefit the electricity sector in supporting more renewable energy which is also one of the most important driving forces in its promotion...... the clean wind energy and latter could be expensive and limited as the neighbouring countries are also installing more renewable energy across their borders. One of the other alternative solutions lies with the local distributed storages which could be provided by the flexible, efficient and quick start...

  13. 77 FR 53880 - Portland General Electric Company; Notice of Application Accepted for Filing, Soliciting Motions...

    Science.gov (United States)

    2012-09-04

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Portland General Electric Company; Notice of Application Accepted for Filing, Soliciting Motions To Intervene, Protests, and Comments Take notice that the following hydroelectric application has been filed with the...

  14. Electrically driven directional motion of a four-wheeled molecule on a metal surface

    NARCIS (Netherlands)

    Kudernac, Tibor; Ruangsupapichat, Nopporn; Parschau, Manfred; Macia, Beatriz; Katsonis, Nathalie; Harutyunyan, Syuzanna R.; Ernst, Karl-Heinz; Feringa, Ben L.

    2011-01-01

    Propelling single molecules in a controlled manner along an unmodified surface remains extremely challenging because it requires molecules that can use light, chemical or electrical energy to modulate their interaction with the surface in a way that generates motion. Nature's motor proteins(1,2)

  15. Reliability Assessment of Offshore Wind Turbines Considering Faults of Electrical / Mechanical Components

    DEFF Research Database (Denmark)

    Kostandyan, Erik; Sørensen, John Dalsgaard

    2013-01-01

    For offshore wind turbines, the cost contribution to Cost of Energy from inspections and Operation & Maintenance can be substantial, and can be expected to increase when wind farms are placed at deeper water depths, further from the coast and in more harsh environments. Estimates of the reliabili...... is considered and related to reliability estimation by taking into account faults e.g. due to failure of an electrical component or loss of grid....

  16. Electricity Generation and Energy Cost Estimation of Large-Scale Wind Turbines in Jarandagh, Iran

    Directory of Open Access Journals (Sweden)

    Kasra Mohammadi

    2014-01-01

    Full Text Available Currently, wind energy utilization is being continuously growing so that it is regarded as a large contender of conventional fossil fuels. This study aimed at evaluating the feasibility of electricity generation using wind energy in Jarandagh situated in Qazvin Province in north-west part of Iran. The potential of wind energy in Jarandagh was investigated by analyzing the measured wind speed data between 2008 and 2009 at 40 m height. The electricity production and economic evaluation of four large-scale wind turbine models for operation at 70 m height were examined. The results showed that Jarandagh enjoys excellent potential for wind energy exploitation in 8 months of the year. The monthly wind power at 70 m height was in the range of 450.28–1661.62 W/m2, and also the annual wind power was 754.40 W/m2. The highest capacity factor was obtained using Suzlon S66/1.25 MW turbine model, while, in terms of electricity generation, Repower MM82/2.05 MW model showed the best performance with total annual energy output of 5705 MWh. The energy cost estimation results convincingly demonstrated that investing on wind farm construction using all nominated turbines is economically feasible and, among all turbines, Suzlon S66/1.25 MW model with energy cost of 0.0357 $/kWh is a better option.

  17. Electric vehicles to support large wind power penetration in future danish power systems

    DEFF Research Database (Denmark)

    Pillai, Jayakrishnan Radhakrishna; Bak-Jensen, Birgitte; Thøgersen, Paul

    2012-01-01

    Electric Vehicles (EVs) could play major role in the future intelligent grids to support a large penetration of renewable energy in Denmark, especially electricity production from wind turbines. The future power systems aims to phase-out big conventional fossil-fueled generators with large number...... and generation. This paper analyses power balancing support services from EVs and the feasible levels of electric vehicle integration possible to provide grid ancillary services in Danish power systems. This evaluation is conducted on typical wind dominated distribution and transmission networks in Denmark...... of variable wind turbines which results in the need for additional balancing power. One of the alternate and local solutions for negotiating the power fluctuations of variable generation could be utilised from the smart charging and discharging of battery storages of EVs operating as flexible demand...

  18. Electric Vehicles for Improved Operation of Power Systems with High Wind Power Penetration

    DEFF Research Database (Denmark)

    Larsen, Esben; Chandrashekhara, Divya K; Østergaard, Jacob

    2008-01-01

    In a power system with a high share of wind energy the wind fluctuation causes a variation in the power generation, which must be compensated from other sources. The situation in Denmark with a penetration of more than 20% wind in yearly average is presented. The introduction of electric drive...... vehicles (EDV) as flexible loads can improve the system operation. Bidirectional power exchange through batteries (vehicle to grid) can be seen as a storage system in the grid. An analysis of possible economical incentives for the vehicle owners will be shown. By control of EDV charging through a price...

  19. Studies for Characterisation of Electrical Properties of DC Collection System in Offshore Wind Farms

    DEFF Research Database (Denmark)

    Chen, Yu-Hsing; Dincan, Catalin Gabriel; Olsen, Rolant Joannesarson

    2016-01-01

    Offshore HVDC-connected wind farms where the wind plant power collection network becomes DC, rather than AC, offer reduced electrical losses, lower equipment ratings potentially leading to lower bill-of-material cost, and undiminished functionality. However, no standards exist for an offshore...... medium-voltage DC power collection cable-based system, routing power from MVDC wind turbines all the way to the HVDC export cable. To progress, it is therefore important to establish some common reference for the design and performance of the components needed in an MVDC collection network. Any suggested...

  20. The contribution of wind energy to electric power generation; Der Beitrag der Windenergie zur Stromerzeugung

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The conference discussed the following five subjects: (1) Status and perspectives of wind power in Germany and Japan; (2) Grid connection of wind power systems; (3) Wind power and electric power supply; (4) Future fields of application, technical perspectives; (5) Panel discussion. [German] Der Tagungsband beinhaltet Beitraege in fuenf Bloecken, die die folgenden Ueberschriften haben: (1) Stand und Perspektiven der Windenergienutzung in Deutschland und Japan; (2) Netzintegration von Windenergieanlagen; (3) Windenergie in der elektrischen Energieversorgung; (4) zukuenftige Anwendungsfelder, technische Perspektiven sowie (5) Paneldiskussion. (AKF)

  1. Combined wind, hydropower and photovoltaic systems for generation of electric power and control of water resources

    International Nuclear Information System (INIS)

    Abid, M.; Karimov, K.S.; Akhmedov, K.M.

    2011-01-01

    In this paper the present day energy consumption and potentialities of utilization of wind- and hydropower resources in some Central and Southern Asian Republics, in particular, in the Republic of Tajikistan, Kyrgyzstan and Pakistan are presented. The maximum consumption of electric power is observed in winter time when hydropower is the minimum, but wind power is the maximum. At the same time water is needed mostly in summer time for irrigation and in winter time for generation of electric power. This results in conflicts between countries that utilize water mostly for irrigation and those which use water for generation of electric power. It is proposed that the utilization of water with the supplement of wind and solar energy will facilitate the proper and efficient management of water resources in Central Asia. In the future in Tajikistan, wind power systems with a capacity of 30-100 MW and more will be installed, providing power balance of the country in winter; hence saving water in reservoirs, especially in drought years. This will provide the integration of electricity generated by wind, hydroelectric power and photovoltaic system in the unified energy system of the country. (author)

  2. Influence of wind power, plug-in electric vehicles, and heat storages on power system investments

    International Nuclear Information System (INIS)

    Kiviluoma, Juha; Meibom, Peter

    2010-01-01

    Due to rising fuel costs, the substantial price for CO 2 emissions and decreasing wind power costs, wind power might become the least expensive source of power for an increasing number of power systems. This poses the questions of how wind power might change optimal investments in other forms of power production and what kind of means could be used to increase power system flexibility in order to incorporate the variable power production from wind power in a cost-effective manner. We have analysed possible effects using an investment model that combines heat and power production and simulates electric vehicles. The model runs in an hourly time scale in order to accommodate the impact of variable power production from wind power. Electric vehicles store electricity for later use and can thus serve to increase the flexibility of the power system. Flexibility can also be upgraded by using heat storages with heat from heat pumps, electric heat boilers and combined heat and power (CHP) plants. Results show that there is great potential for additional power system flexibility in the production and use of heat. (author)

  3. [Hygienic problems in the location of modern wind electric power stations in their design].

    Science.gov (United States)

    Kireeva, I S; Makhniuk, V M; Akimenko, V Ia; Dumanskiĭ, Iu D; Semashko, P V

    2013-01-01

    Hygienic aspects of the placement of wind power plants (WPP) in connection with the intensive development of wind power and the lack of systematic information on their effects of the environment and living conditions of the population are becoming more actual. In the article there are considered results of the sanitary-epidemiological expertise of the construction project of three modern large wind farm (the South - Ukrainian, Tiligulskaya and Pokrovskaya) with a total capacity offrom 180 to 500 MW of wind farms with 2.3 MW power generators of wind turbines. It is shown that in the process of wind farm construction a contamination of the environment (air soil, ground water) may take place due to the working of construction equipment and vehicle, excavation, welding and other operations, in the exploitation of wind farm there can be created elevated levels of acoustic and electromagnetic pollution in the neighborhood and emergencies with the destruction of WPP in adverse weather conditions. Based on the calculations presented in the projects, and the analysis of data on the impact offoreign windfarm on the environment it was found that the limiting factor of the influence is the wind farm noise pollution in the audio frequency range that extends beyond the territory of wind fields, electromagnetic radiation is recorded within the hygienic standards and below only in the immediate vicinity of its sources (electrical equipment and power lines). For considered modern wind farms there was grounded sanitary protective zone with dimensions of 700 mfrom the outermost wind turbines by the noise and it was recommended compliance distance of200 mfrom the wind turbine to limit any activity and people staying in times of possible emergency situations in adverse weather conditions.

  4. Utilizing a vanadium redox flow battery to avoid wind power deviation penalties in an electricity market

    International Nuclear Information System (INIS)

    Turker, Burak; Arroyo Klein, Sebastian; Komsiyska, Lidiya; Trujillo, Juan José; Bremen, Lueder von; Kühn, Martin; Busse, Matthias

    2013-01-01

    Highlights: • Vanadium redox flow battery utilized for wind power grid integration was studied. • Technical and financial analyses at single wind farm level were performed. • 2 MW/6 MW h VRFB is suitable for mitigating power deviations for a 10 MW wind farm. • Economic incentives might be required in the short-term until the VRFB prices drop. - Abstract: Utilizing a vanadium redox flow battery (VRFB) for better market integration of wind power at a single wind farm level was evaluated. A model which combines a VRFB unit and a medium sized (10 MW) wind farm was developed and the battery was utilized to compensate for the deviations resulting from the forecast errors in an electricity market bidding structure. VRFB software model which was introduced in our previous paper was integrated with real wind power data, power forecasts and market data based on the Spanish electricity market. Economy of the system was evaluated by financial assessments which were done by considering the VRFB costs and the amount of deviation penalty payments resulting from forecast inaccuracies

  5. Windonomics. Empirical essays on the economics of wind power in the Nordic electricity market

    Energy Technology Data Exchange (ETDEWEB)

    Mauritzen, Johannes

    2012-07-01

    From the introduction: The following chapters in this dissertation take up three topics surrounding the interaction of wind power investment in Denmark and the functioning of the deregulated Nordic electricity market. The first two chapters take up the issue of how wind power a affects prices in the deregulated market. I find that electricity price variation in the spot market is lower in days with more wind power. In the following chapter I extend this analysis to see how wind power in Denmark affects prices in neighbouring hydro power dominated Norway. I find that wind power affects the magnitude of trade between the countries asymmetrically - dependent on the net direction of trade. I also find that wind power has a slight but statistically significant negative effect on prices in Norway, likely due to a slackening of hydro power producers supply constraints. The last chapter starts with the observation that most turbines are scrapped in order to make room for a newer turbine. An opportunity cost that comes from the interaction of scarce land resources, technological change and government policy is then a dominant reason for the scrapping of wind turbines. This leads to the implication that turbines located on windier, better situated land have a higher risk of being scrapped. Policy is also shown to have a strong and in some respects unexpected effect on scrappings. Over the last two decades two major trends have taken place in power markets around the world. The first has been a movement towards market based power systems. Vertically integrated power companies have been split into component generation, transmission and retailing companies. Generation and retailing have been opened to competition. Increasingly, regulated prices and bilateral trade are being replaced by regulated markets that establish prices through auction mechanisms. The second trend has been investment in renewable and intermittent energy sources - notably wind power. What started as

  6. Analytical Derivation of Electrical-Side Maximum Power Line for Wind Generators

    Directory of Open Access Journals (Sweden)

    Sergei Kolesnik

    2017-09-01

    Full Text Available In order to enhance the maximum power point tracking (MPPT speed of solar generators, offline calculated maximum power line (MPL is often used as a feed-forward signal added to the output of MPPT controller. MPL is nonlinear static electrical characteristic of renewable energy generators connecting all the maximum power points for given temperature. In this letter, electrical side MPL is derived for a typical wind turbine generator (WTG. It is shown that MPLs of solar and wind generators possess similar structure, supporting the similarity between the two energy conversion processes.

  7. An innovative medium speed wind turbine rotor blade design for low wind regime (electrical power generation)

    International Nuclear Information System (INIS)

    Abas Abd Wahab; Chong Wen Tong

    2001-01-01

    This paper describes the preliminary study of a small-scale wind turbine rotor blade (a low wind speed region turbine). A new wind turbine rotor blade (AE2 blade) for stand alone system has been conceptualized, designed, constructed and tested. The system is a reduced size prototype (half-scaled) to develop an efficient (adapted to Malaysian wind conditions)and cost effective wind energy conversion system (WECS) with local design and production technique. The blades were constructed from aluminium sheet with metal blending technique. The layout and design of rotor blade, its innovative features and test results are presented. Results from indoor test showed that the advantages of AE2 blade in low speed, with the potential of further improvements. The best rotor efficiency, C P attained with simple AE2 blades rotor (number of blade = 3) was 37.3% (Betz efficiency = 63%) at tip speed ratio (TSR) = 3.6. From the fabrication works and indoor testing, the AE2 blade rotor has demonstrated its structural integrity (ease of assembly and transportation), simplicity, acceptable performance and low noise level. (Author)

  8. The economic benefit of short-term forecasting for wind energy in the UK electricity market

    International Nuclear Information System (INIS)

    Barthelmie, R.J.; Murray, F.; Pryor, S.C.

    2008-01-01

    In the UK market, the total price of renewable electricity is made up of the Renewables Obligation Certificate and the price achieved for the electricity. Accurate forecasting improves the price if electricity is traded via the power exchange. In order to understand the size of wind farm for which short-term forecasting becomes economically viable, we develop a model for wind energy. Simulations were carried out for 2003 electricity prices for different forecast accuracies and strategies. The results indicate that it is possible to increase the price obtained by around pound 5/MWh which is about 14% of the electricity price in 2003 and about 6% of the total price. We show that the economic benefit of using short-term forecasting is also dependant on the accuracy and cost of purchasing the forecast. As the amount of wind energy requiring integration into the grid increases, short-term forecasting becomes more important to both wind farm owners and the transmission/distribution operators. (author)

  9. Progress in IEC 61400-27. Electrical simulation models for wind power generation

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Poul [DTU Wind Energy, Roskilde (Denmark); Andresen, Bjoern; Bech, John [Siemens Wind Power, Brande (Denmark). Electrical Systems and Generators; Fortmann, Jens [REpower Systems AG, Osterroenfeld (Germany). Wind Power Plant; Pourbeik, Pouyan [Electric Power Research Institute, Inc. (EPRI), Knoxville, TN (United States). Grid Operations and Planning

    2012-07-01

    This paper presents the status of the ongoing work in IEC Technical Committee 88 Working Group 27 (TC88 WG27) developing a standard IEC 61400-27 for ''Electrical simulation models for wind power generation''. The purpose of this standardization work is to define generic simulation models for wind turbines (part 1) and wind power plants (part 2), which are intended for short-term power system stability analyses. WG27 submitted the first CD of Part 1 in December 2012. The CD describes generic wind turbine models and a procedure for validation of wind turbine models. The generic model description consists of a general model structure intending to cover existing as well as future types of wind turbines, and specific fundamental frequency positive sequence models for the four wind turbine types which are widely used today. The validation procedure can be applied to the generic models specified in the standard, or to manufacturer specific fundamental frequency models. The paper will provide a general description of the wind turbine models, a more detailed description of type 4 models, a description of the validation procedure and finally a validation example. Part 2 is in an early stage of development. IEC has approved the New Work Item Proposal (NWIP) of part 2, and this work has officially started 1 October 2012. (orig.)

  10. Study on a hypothetical replacement of nuclear electricity by wind power in Sweden

    Science.gov (United States)

    Wagner, F.; Rachlew, E.

    2016-05-01

    The Swedish electricity supply system benefits strongly from the natural conditions which allow a high share of hydroelectricity. A complete supply is, however, not possible. Up to now, nuclear power is the other workhorse to serve the country with electricity. Thus, electricity production of Sweden is basically CO2 -free and Sweden has reached an environmental status which others in Europe plan to reach in 2050. Furthermore, there is an efficient exchange within the Nordic countries, Nordpol, which can ease possible capacity problems during dry cold years. In this study we investigate to what extent and with what consequences the base load supply of nuclear power can be replaced by intermittent wind power. Such a scenario leads unavoidably to high wind power installations. It is shown that hydroelectricity cannot completely smooth out the fluctuations of wind power and an additional back-up system using fossil fuel is necessary. From the operational dynamics, this system has to be based on gas. The back-up system cannot be replaced by a storage using surplus electricity from wind power. The surplus is too little. To overcome this, further strong extension of wind power is necessary which leads, however, to a reduction of the use of hydroelectricity if the annual consumption is kept constant. In this case one fossil-free energy form is replaced by another, however, more complex one. A mix of wind power at 22.3GW plus a gas based back-up system with 8.6GW producing together 64.8TWh would replace the present infrastructure with 9GW nuclear power producing 63.8TWh electricity. The specific CO2 -emission increases to the double in this case. Pumped storage for the exclusive supply of Sweden does not seem to be a meaningful investment.-1

  11. Natural turbulence electrical power generator. [using wave action or random motion

    Science.gov (United States)

    Grana, D. C.; Wilem, R. T. (Inventor)

    1980-01-01

    An energy conversion apparatus is disclosed in which a stator, fixed to a watertight housing, is coupled to a rotor by a helical spring which suspends the rotor from the housing. Natural turbulence of a fluid, such as water or air, causes acceleration of the housing, and hence, acceleration of the stator. Inertia of the rotor, coupled to the stator through the helical spring and the housing, causes relative motion, both longitudinal and rotational, between the stator and the rotor. The rotational motion between the rotor, and the stator is used to generate electrical current.

  12. Water droplets' internal fluidity during horizontal motion on a superhydrophobic surface with an external electric field.

    Science.gov (United States)

    Sakai, Munetoshi; Kono, Hiroki; Nakajima, Akira; Sakai, Hideki; Abe, Masahiko; Fujishima, Akira

    2010-02-02

    On a superhydrophobic surface, the internal fluidity of water droplets with different volumes (15, 30 microL) and their horizontal motion in an external electric field were evaluated using particle image velocimetry (PIV). For driving of water droplets on a superhydrophobic coating between parallel electrodes, it was important to place them at appropriate positions. Droplets moved with slipping. Small droplets showed deformation that is more remarkable. Results show that the dielectrophoretic force induced the initial droplet motion and that the surface potential gradient drove the droplets after reaching the middle point between electrodes.

  13. For the definition of capacity effects of electricity generation from wind power and solar radiation

    International Nuclear Information System (INIS)

    Kaltschmitt, M.

    1996-01-01

    It is the objective of this contribution to define the calculable really available output of a fluctuating electricity generation from wind energy and solar radiation. Apart from that, the methods for determining the really available output are explained, as far as they are necessary for understanding the definitions. Exemplified on a simulated large-scale regenerative electricity generation in Germany, in addition, some defined values are calculated and discussed. (orig.) [de

  14. FENCH-analysis of electricity generation greenhouse gas emissions from solar and wind power in Germany

    International Nuclear Information System (INIS)

    Hartmann, D.

    1997-01-01

    The assessment of energy supply systems with regard to the influence on climate change requires not only the quantification of direct emissions caused by the operation of a power plant. It also has to take into account indirect emissions resulting from e.g. construction and dismounting of the power plant. Processes like manufacturing the materials for building the plant, the transportation of components and the construction and maintenance of the power plant are included. A tool to determine and assess the energy and mass flows is the Life Cycle Analysis (LCA) which allows the assessment of environmental impacts related to a product or service. In this paper a FENCH (Full Energy Chain)-analysis based on a LCA of electricity production from wind and solar power plants under operation conditions typical for application its Germany is presented. The FENCH-analysis is based on two methods, Process Chain Analysis (PCA) and Input-Output-Analysis (IOA) which are illustrated by the example of an electricity generation from a wind power plant. The calculated results are shown for the cumulated (indirect and direct) Greenhouse-Gas (GHG)-emissions for an electricity production from wind and solar power plants. A comparison of the results to the electricity production from a coal fired power plant is performed. At last a comparison of 1 kWh electricity from renewable energy to 1 kWh from fossil energy carrier has to be done, because the benefits of 1 kWh electricity from various types of power plants are different. Electricity from wind energy depends on the meteorological conditions while electricity from a fossil fired power plant is able to follow the power requirements of the consumers nearly all the time. By considering the comparison of the different benefit provided the GHG-Emissions are presented. (author)

  15. Feasibility of generating electricity for clinics using wind turbines

    CSIR Research Space (South Africa)

    Szewczuk, S

    2015-08-01

    Full Text Available turbines It is intended that all the power required to operate a clinic should be generated on site allowing the building to function off-grid. A review was done of wind turbine machines of less than 100kW in size. (Szewczuk et al, 2010) Topics covered... were:  Markets and applications  Market drivers and barriers  Review of common applications of SWT’s Small-scale remote and off-grid power (residential, village or remote) are used for supplying energy to rural, off-grid applications...

  16. Superconductor Armature Winding for High Performance Electrical Machines

    Science.gov (United States)

    2016-12-05

    secured using dental floss . Figure 6.20. Ninety, reacted MgB2 triplets mounted to the outer surface of a G-10 cylinder in preparation for... substrate . Key characteristic parameters of the field winding are summarized in Table 2.6. A 2 mm wide conductor is operated at 48% of its critical...on specially textured, high aspect ratio metallic substrates . YBCO tapes are typically on order of 0.1 mm thick and between 4 mm and 12 mm wide

  17. Resilience of electricity grids against transmission line overloads under wind power injection at different nodes.

    Science.gov (United States)

    Schiel, Christoph; Lind, Pedro G; Maass, Philipp

    2017-09-14

    A steadily increasing fraction of renewable energy sources for electricity production requires a better understanding of how stochastic power generation affects the stability of electricity grids. Here, we assess the resilience of an IEEE test grid against single transmission line overloads under wind power injection based on the dc power flow equations and a quasi-static grid response to wind fluctuations. Thereby we focus on the mutual influence of wind power generation at different nodes. We find that overload probabilities vary strongly between different pairs of nodes and become highly affected by spatial correlations of wind fluctuations. An unexpected behaviour is uncovered: for a large number of node pairs, increasing wind power injection at one node can increase the power threshold at the other node with respect to line overloads in the grid. We find that this seemingly paradoxical behaviour is related to the topological distance of the overloaded line from the shortest path connecting the wind nodes. In the considered test grid, it occurs for all node pairs, where the overloaded line belongs to the shortest path.

  18. Electricity cost effects of expanding wind power and integrating energy sectors

    Directory of Open Access Journals (Sweden)

    Victor Maxwell

    2015-06-01

    Full Text Available Recently, questions have arisen in Denmark as to how and why public funding should be allocated to wind power producers. This is, among other reasons, due to pressure from industrial electricity consumers who want their overall energy costs lowered. Utilising existing wind power subsidies across energy sectors may be an effective means of dealing with these concerns. The following article takes the case of a community owned renewable energy project as a microcosm for the entire Danish energy system. The local project seeks to integrate energy sectors so as to create physical and financial conditions which could allow wind power producers to reduce their reliance on subsidies. It is found that the strategy may be effective in lowering the overall energy costs of electricity consumers. Further, it is found possible to scale up this strategy and realise benefits on a national scale.

  19. Insertion of wind energy in the deregulated electricity market: a Brazilian study

    Energy Technology Data Exchange (ETDEWEB)

    Bezerra, P.; Freire, M.L.C. [Companhia Hidro Electrica do Sao Francisco (CHESF) (Brazil); Codeceira Neto, A. [Companhia Hidro Electrica do Sao Francisco (CHESF) (Brazil)]|[Univ. de Pernambuco - UPE (Brazil); Pereira de Araujo, M.R. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia

    2000-07-01

    This paper highlights the insertion of wind power generation within the Brazilian electricity market, showing that it can be competitive with the conventional combined cycle technology using natural gas fuel. The favourable conditions offered by the region, which concentrates the load centres on the cost, together with the benefits obtained from the wind speed in that region, indicate this alternative energy as an option for the local electricity market. The economics of grid connected wind power depend upon the financial perspective considered. Taking into account the use for the Brazilian government of normative values in order to regulate the energy market, comparisons of costs for different technologies using internal rules have been used in this new model. (orig.)

  20. The role of co-located storage for wind power producers in conventional electricity markets

    KAUST Repository

    Bitar, E.

    2011-06-01

    In this paper we study the problem of optimizing contract offerings for an independent wind power producer (WPP) participating in conventional day-ahead forward electricity markets for energy. As wind power is an inherently variable source of energy and is difficult to predict, we explore the extent to which co-located energy storage can be used to improve expected profit and mitigate the the financial risk associated with shorting on the offered contracts. Using a simple stochastic model for wind power production and a model for the electricity market, we show that the problem of determining optimal contract offerings for a WPP with co-located energy storage can be solved using convex programming.

  1. Review of DC System Technologies for Large Scale Integration of Wind Energy Systems with Electricity Grids

    Directory of Open Access Journals (Sweden)

    Sheng Jie Shao

    2010-06-01

    Full Text Available The ever increasing development and availability of power electronic systems is the underpinning technology that enables large scale integration of wind generation plants with the electricity grid. As the size and power capacity of the wind turbine continues to increase, so is the need to place these significantly large structures at off-shore locations. DC grids and associated power transmission technologies provide opportunities for cost reduction and electricity grid impact minimization as the bulk power is concentrated at single point of entry. As a result, planning, optimization and impact can be studied and carefully controlled minimizing the risk of the investment as well as power system stability issues. This paper discusses the key technologies associated with DC grids for offshore wind farm applications.

  2. Impact of Penetration Wind Turbines on Transient Stability in Sulbagsel Electrical Interconnection System

    Science.gov (United States)

    Nurtrimarini Karim, Andi; Mawar Said, Sri; Chaerah Gunadin, Indar; Darusman B, Mustadir

    2018-03-01

    This paper presents a rotor angle analysis when transient disturbance occurs when wind turbines enter the southern Sulawesi electrical interconnection system (Sulbagsel) both without and with the addition of a Power Stabilizer (PSS) control device. Time domain simulation (TDS) method is used to analyze the rotor angle deviation (δ) and rotor angle velocity (ω). A total of 44 buses, 47 lines, 6 transformers, 15 generators and 34 loads were modeled for analysis after the inclusion of large-scale wind turbines in the Sidrap and Jeneponto areas. The simulation and computation results show the addition of PSS devices to the system when transient disturbance occurs when the winds turbine entering the Sulbagsel electrical system is able to dampen and improve the rotor angle deviation (δ) and the rotor angle velocity (ω) towards better thus helping the system to continue operation at a new equilibrium point.

  3. Motion

    CERN Document Server

    Graybill, George

    2007-01-01

    Take the mystery out of motion. Our resource gives you everything you need to teach young scientists about motion. Students will learn about linear, accelerating, rotating and oscillating motion, and how these relate to everyday life - and even the solar system. Measuring and graphing motion is easy, and the concepts of speed, velocity and acceleration are clearly explained. Reading passages, comprehension questions, color mini posters and lots of hands-on activities all help teach and reinforce key concepts. Vocabulary and language are simplified in our resource to make them accessible to str

  4. Hybrid power system (hydro, solar and wind) for rural electricity generation

    International Nuclear Information System (INIS)

    Mahinda Kurukulasuriya

    2000-01-01

    Generation of affordable cheap electric energy for rural development by a hybrid power system (10-50 kW) of hydropower, solar and wind energies on self determining basis and computer application to determine its performance. In this paper the following topics were discussed, design of hybrid power system, its justification and economic analysis, manufacturing and installation of the system. (Author)

  5. Flexible interaction of plug-in electric vehicle parking lots for efficient wind integration

    International Nuclear Information System (INIS)

    Heydarian-Forushani, E.; Golshan, M.E.H.; Shafie-khah, M.

    2016-01-01

    Highlights: • Interactive incorporation of plug-in electric vehicle parking lots is investigated. • Flexible energy and reserve services are provided by electric vehicle parking lots. • Uncertain characterization of electric vehicle owners’ behavior is taken into account. • Coordinated operation of parking lots can facilitate wind power integration. - Abstract: The increasing share of uncertain wind generation has changed traditional operation scheduling of power systems. The challenges of this additional variability raise the need for an operational flexibility in providing both energy and reserve. One key solution is an effective incorporation of plug-in electric vehicles (PEVs) into the power system operation process. To this end, this paper proposes a two-stage stochastic programming market-clearing model considering the network constraints to achieve the optimal scheduling of conventional units as well as PEV parking lots (PLs) in providing both energy and reserve services. Different from existing works, the paper pays more attention to the uncertain characterization of PLs takes into account the arrival/departure time of PEVs to/from the PL, the initial state of charge (SOC) of PEVs, and their battery capacity through a set of scenarios in addition to wind generation scenarios. The results reveal that although the cost saving as a consequence of incorporating PL to the grid is below 1% of total system cost, however, flexible interactions of PL in the energy and reserve markets can promote the integration of wind power more than 13.5%.

  6. Combined scheduling of electricity and heat in a microgrid with volatile wind power

    DEFF Research Database (Denmark)

    Xu, Lizhong; Yang, Guang Ya; Xu, Zhao

    2011-01-01

    An optimization model is developed for scheduling electricity and heat production in a microgrid under a day-ahead market environment considering the operation constraints and the volatility of wind power generation. The model optimizes the total operation costs from energy and heating consumptio...

  7. Natural Gas, Wind and Nuclear Options for Generating Electricity in a Carbon Constrained World

    NARCIS (Netherlands)

    Kooten, van G.C.

    2012-01-01

    A linear programming model is used to examine the impact of carbon taxes on the optimal generation mix in the Alberta electrical system. The model permits decommissioning of generating assets with high carbon dioxide emissions and investment in new gas-fired, wind and, in some scenarios, nuclear

  8. Trends in Wind Turbine Generators, and the Role of Electrical Steels

    DEFF Research Database (Denmark)

    Henriksen, Matthew Lee; Jensen, Bogi Bech

    2014-01-01

    Designs of permanent magnet synchronous machines suitable for operation as wind turbine generators are presented and discussed. Design differences in machines intended for operation in geared and direct drive systems are illustrated . Special emphasis is given to the effect of varying...... the electrical steel used for stator laminations....

  9. Drift motion of a charged particle in the crossed axial magnetic and radial electric fields, and the electric field of a rotating potential wave

    International Nuclear Information System (INIS)

    Eliseev, Yu.N.; Stepanov, K.N.

    1983-01-01

    In the drift motion approximation solution of the problem is obtained on the motion of a nonrelativistic charged particle in the crossed axial magnetic and radial electric fields, and the electric field of a rotating potential wave under cherenkov and modified cyclotron resonances. The static radial electric field potential is supposed to be close to the parabolic one. The drift motion equations and their integrals are preseOted. The experimentally obtained effect of plasma ionic component division in the crossed fields under the excitation of ion cyclotron oscillations is explained with the help of the theory developed in the paper

  10. Electrical production for domestic and industrial applications using hybrid PV-wind system

    International Nuclear Information System (INIS)

    Essalaimeh, S.; Al-Salaymeh, A.; Abdullat, Y.

    2013-01-01

    Highlights: ► Modeling and building hybrid system of PV and wind turbine. ► Investigation of the electrical generation under Amman–Jordan’s climate. ► Configuration of theoretical and actual characteristics of the hybrid system. ► Testing effects of dust, inclination and load on the electrical generation. ► Financial analysis for various applications. - Abstract: The present work shows an experimental investigation of using a combination of solar and wind energies as hybrid system for electrical generation under the Jordanian climate conditions. The generated electricity has been utilized for different types of applications and mainly for space heating and cooling. The system has also integration with grid connection to have more reliable system. Measurements included the solar radiation intensity, the ambient temperature, the wind speed and the output power from the solar PV panels and wind turbine. The performance characteristic of the PV panels has been obtained by varying the load value through a variable resistance. Some major factors have been studied and practically measured; one of them is the dust effect on electrical production efficiency for photovoltaic panels. Another factor is the inclination of the PV panels, where varying the angle of inclination has a seasonal importance for gathering the maximum solar intensity. Through mathematical calculation and the collected and measured data, a simple payback period has been calculated of the hybrid system in order to study the economical aspects of installing such a system under Jordanian climate conditions and for different usages and local tariffs including domestic, industrial and commercial applications. It was found through this work that the generated electricity of hybrid system and under Jordanian climate conditions can be utilized for electrical heating and cooling through split units and resistive heaters.

  11. Wind-Electric Power Potential Assessment for Three Locations in East Java-Indonesia

    Directory of Open Access Journals (Sweden)

    Ali Musyafa

    2011-08-01

    Full Text Available This paper reports our effort to asses wind energy potentials for three locations in East Java. We used wind speed data over a period of almost 3 years, i.e. in period of June 2006 – August 2008. Data were taken from direct measurement in locations in East Java Province, i.e. Sampang (Madura, Juanda (Surabaya, and Sawahan (Nganjuk. The short-term of wind speed mean in monthly signifies to wind-speed value ”which parallels to the wind turbine power curve value” were used to estimate the annual energy output for a 1 MW installed capacity wind farm on the each site 100 of 10kW rated wind turbines were used in the analysis. The short term of wind speed mean at Surabaya and Nganjuk were 2.34, 3.03 and 1.97 m/s at 2 m Above Ground Level (AGL, respectively. In both locations, wind speeds were observed during the day time between 04.00 and 18.00 and relatively smaller ones between 19.00 and 03.00 period. Meanwhile, in Sampang (Madura the higher wind speeds were observed between 20.00 and 06.00, and relatively smaller between 07.00 and 19.00 period. The 1 MW windfarm at Sampang, Surabaya and Nganjuk can produce 1.284; 1.199 and 1.008 MWh of electricity yearly, taking into consideration of the temperature adjustment coefficien of about 6 %. The plant capacity factor at Sampang, Surabaya and Nganjuk were found to be 30.02 %, 30.00 % and 30.01 % respectively. Additionally, it is noticed that these site can contribute to the avoidance of 0.904; 0.846 and 0.709 tons/year of CO2 equivalent Green House Gases (GHG from entering into the local atmosphere, thus creating a clean and healthy athmosphere for local inhabitants.

  12. Wind Energy Potential Assessment for Electric Pumps of Agriculture in Broujerd

    Directory of Open Access Journals (Sweden)

    M Jalalvand

    2014-09-01

    Full Text Available In order to restrain the potential of wind energy, the first step is to determine the wind energy potential. In this study the wind data was used from the three-hour frequency recording of 10-year period (2002-2011. To predict the occurrence probability of each wind speed, the two-parameter Weibull function was used. The goodness of fit test by Chi-Square test showed that the wind speed distribution is not represented by the typical two- parameter Weibull function for all the months. Weibull probability density function has a good fit for eleven months, but for the 9th month of the year (September, it is not fitted. Thus, four-parameter Weibull probability function has been developed to analyze the wind speed frequency distribution in that region for the mentioned months. The electrical energy consumption of agricultural water wells in the region was also calculated for the desired periods of the year. Energy demand and energy supply were matched. Data analysis was performed using SPSS 18.0.0, MATLAB 7.13.0.564 and WIDOGRAPHER 3.0.2. The results show that in Broujerd, to exploit the wind energy at all times of the year, it is necessary to have at least 39 turbines of 2300 kW with 99 meters tower. If the desired turbines are used, there will be extra energy and also, agriculture will be continued towards sustainable development.

  13. Stackelberg Game Model of Wind Farm and Electric Vehicle Battery Switch Station

    Science.gov (United States)

    Jiang, Zhe; Li, Zhimin; Li, Wenbo; Wang, Mingqiang; Wang, Mengxia

    2017-05-01

    In this paper, a cooperation method between wind farm and Electric vehicle battery switch station (EVBSS) was proposed. In the pursuit of maximizing their own benefits, the cooperation between wind farm and EVBSS was formulated as a Stackelberg game model by treating them as decision makers in different status. As the leader, wind farm will determine the charging/discharging price to induce the charging and discharging behavior of EVBSS reasonably. Through peak load shifting, wind farm could increase its profits by selling more wind power to the power grid during time interval with a higher purchase price. As the follower, EVBSS will charge or discharge according to the price determined by wind farm. Through optimizing the charging /discharging strategy, EVBSS will try to charge with a lower price and discharge with a higher price in order to increase its profits. Since the possible charging /discharging strategy of EVBSS is known, the wind farm will take the strategy into consideration while deciding the charging /discharging price, and will adjust the price accordingly to increase its profits. The case study proved that the proposed cooperation method and model were feasible and effective.

  14. Electricity market participation of wind farms: the success story of the Spanish pragmatism

    Energy Technology Data Exchange (ETDEWEB)

    Rivier Abbad, Juan, E-mail: jrivier@iberdrola.e [Iberdrola Renovables, 28033 Madrid (Spain)

    2010-07-15

    In the last 10 years, more than 15 GW of wind power (Asociacion Empresarial Eolica (Spanish Wind Energy Association), Nota de prensa (Press release) 17 de enero de 2008. (http://www.aeeolica.org/doc/NP_080117_Espana_supera_los_15000_MW_eolicos.pdf)) have been installed in Spain, of which more than 3.5 GW in 2007. Furthermore, plans are to reach 20 GW by 2010 and there are expectations of an installed capacity exceeding 40 GW by 2020. This article will present the innovative solutions for technical and economical integration that allow to reach such high level wind penetration objectives (the system peaks at around 44 GW and is almost isolated). It will be described how the regulation has evolved from a pure Feed-in-Tariff to a market+premium option, where technical and economic integration has been a priority. Today, approximately 97% of installed wind capacity accesses the Spanish wholesale electricity market. Market integration has been crucial, sending the correct signals to participants to look for the optimum technical solutions. Technical improvements have come from both wind power producers (fault-ride-through capabilities, visibility and controllability of wind power, power production forecasting, reactive power control) and the system operator (specific control centre dedicated to Renewable Energy Sources (RES), new security analysis tools, gaining technical confidence of wind capabilities).

  15. Electricity market participation of wind farms. The success story of the Spanish pragmatism

    Energy Technology Data Exchange (ETDEWEB)

    Rivier Abbad, Juan [Iberdrola Renovables, 28033 Madrid (Spain)

    2010-07-15

    In the last 10 years, more than 15 GW of wind power (Asociacion Empresarial Eolica (Spanish Wind Energy Association), Nota de prensa (Press release) 17 de enero de 2008. http://www.aeeolica.org/doc/NP{sub 0}80117{sub E}spana{sub s}upera{sub l}os{sub 1}5000{sub M}W{sub e}olicos.pdf) have been installed in Spain, of which more than 3.5 GW in 2007. Furthermore, plans are to reach 20 GW by 2010 and there are expectations of an installed capacity exceeding 40 GW by 2020. This article will present the innovative solutions for technical and economical integration that allow to reach such high level wind penetration objectives (the system peaks at around 44 GW and is almost isolated). It will be described how the regulation has evolved from a pure Feed-in-Tariff to a market+premium option, where technical and economic integration has been a priority. Today, approximately 97% of installed wind capacity accesses the Spanish wholesale electricity market. Market integration has been crucial, sending the correct signals to participants to look for the optimum technical solutions. Technical improvements have come from both wind power producers (fault-ride-through capabilities, visibility and controllability of wind power, power production forecasting, reactive power control) and the system operator (specific control centre dedicated to Renewable Energy Sources (RES), new security analysis tools, gaining technical confidence of wind capabilities). (author)

  16. Price Forecasting of Electricity Markets in the Presence of a High Penetration of Wind Power Generators

    Directory of Open Access Journals (Sweden)

    Saber Talari

    2017-11-01

    Full Text Available Price forecasting plays a vital role in the day-ahead markets. Once sellers and buyers access an accurate price forecasting, managing the economic risk can be conducted appropriately through offering or bidding suitable prices. In networks with high wind power penetration, the electricity price is influenced by wind energy; therefore, price forecasting can be more complicated. This paper proposes a novel hybrid approach for price forecasting of day-ahead markets, with high penetration of wind generators based on Wavelet transform, bivariate Auto-Regressive Integrated Moving Average (ARIMA method and Radial Basis Function Neural Network (RBFN. To this end, a weighted time series for wind dominated power systems is calculated and added to a bivariate ARIMA model along with the price time series. Moreover, RBFN is applied as a tool to correct the estimation error, and particle swarm optimization (PSO is used to optimize the structure and adapt the RBFN to the particular training set. This method is evaluated on the Spanish electricity market, which shows the efficiency of this approach. This method has less error compared with other methods especially when it considers the effects of large-scale wind generators.

  17. Correlated wind-power production and electric load scenarios for investment decisions

    International Nuclear Information System (INIS)

    Baringo, L.; Conejo, A.J.

    2013-01-01

    Highlights: ► Investment models require an accurate representation of the involved uncertainty. ► Demand and wind power production are correlated and uncertain parameters. ► Two methodologies are provided to represent uncertainty and correlation. ► An accurate uncertainty representation is crucial to get optimal results. -- Abstract: Stochastic programming constitutes a useful tool to address investment problems. This technique represents uncertain input data using a set of scenarios, which should accurately describe the involved uncertainty. In this paper, we propose two alternative methodologies to efficiently generate electric load and wind-power production scenarios, which are used as input data for investment problems. The two proposed methodologies are based on the load- and wind-duration curves and on the K-means clustering technique, and allow representing the uncertainty of and the correlation between electric load and wind-power production. A case study pertaining to wind-power investment is used to show the interest of the proposed methodologies and to illustrate how the selection of scenarios has a significant impact on investment decisions.

  18. Method for analysing the adequacy of electric power systems with wind power plants and energy storages

    Directory of Open Access Journals (Sweden)

    Perzhabinsky Sergey

    2017-01-01

    Full Text Available Currently, renewable energy sources and energy storage devices are actively introduced into electric power systems. We developed method to analyze the adequacy of these electric power systems. The method takes into account the uncertainty of electricity generation by wind power plants and the processes of energy storage. The method is based on the Monte Carlo method and allowed to use of long-term meteorological data in open access. The performed experimental research of electrical power system is constructed on the basis of the real technical and meteorological data. The method allows to estimate of effectiveness of introducing generators based on renewable energy sources and energy storages in electric power systems.

  19. Significance of in-structure generated motion in seismic qualification electrical devices

    International Nuclear Information System (INIS)

    Thinnes, G.; Glozman, V.

    1988-07-01

    The Idaho National Engineering Laboratory (INEL) has been conducting a research study to assist the United States Nuclear Regulatory Commission (USNRC) in determining susceptibility of electrical devices to in-structure generated motion sometimes present in electrical cabinets. In Phase I of this study, a survey of past seismic qualification tests conducted at Wyle Laboratories on various electrical and control equipment housed in nuclear grade cabinets was taken to identify components which experienced a rattling environment. The INEL has used several different methods to reduce that data and has determined the existence of a number of device anomalies in the presence of high frequency cabinet response to earthquake-type excitation motion. However, causality between the high frequency content and the malfunctions could not be conclusively confirmed. Phase II of the study consisted of shake table testing for the most prevalent malfunction discovered in the survey, relay chatter, with excitation frequency content in the seismic range and higher. This report will document the results of Phase I and II of the study. Insight into the susceptibility of electrical devices to rattling and characterization of relay chatter mechanisms offers guidance in addressing rattling effects during qualifications

  20. Coupling Electric Vehicles and Power Grid through Charging-In-Motion and Connected Vehicle Technology

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jan-Mou [ORNL; Jones, Perry T [ORNL; Onar, Omer C [ORNL; Starke, Michael R [ORNL

    2014-01-01

    A traffic-assignment-based framework is proposed to model the coupling of transportation network and power grid for analyzing impacts of energy demand from electric vehicles on the operation of power distribution. Although the reverse can be investigated with the proposed framework as well, electricity flowing from a power grid to electric vehicles is the focus of this paper. Major variables in transportation network (including link flows) and power grid (including electricity transmitted) are introduced for the coupling. Roles of charging-in-motion technology and connected vehicle technology have been identified in the framework of supernetwork. A linkage (i.e. individual energy demand) between the two networks is defined to construct the supernetwork. To determine equilibrium of the supernetwork can also answer how many drivers are going to use the charging-in-motion services, in which locations, and at what time frame. An optimal operation plan of power distribution will be decided along the determination simultaneously by which we have a picture about what level of power demand from the grid is expected in locations during an analyzed period. Caveat of the framework and possible applications have also been discussed.

  1. Wind power demonstration and siting problems. [for recharging electrically driven automobiles

    Science.gov (United States)

    Bergey, K. H.

    1973-01-01

    Technical and economic feasibility studies on a small windmill to provide overnight charging for an electrically driven car are reported. The auxiliary generator provides power for heating and cooling the vehicle which runs for 25 miles on battery power alone, and for 50 miles with the onboard charger operating. The blades for this windmill have a diameter of 12 feet and are coupled through to a conventional automobile alternator so that they are able to completely recharge car batteries in 8 hours. Optimization of a windmill/storage system requires detailed wind velocity information which permits rational sitting of wind power system stations.

  2. Combined scheduling of electricity and heat in a microgrid with volatile wind power

    DEFF Research Database (Denmark)

    Xu, Lizhong; Yang, Guang Ya; Xu, Zhao

    2011-01-01

    An optimization model is developed for scheduling electricity and heat production in a microgrid under a day-ahead market environment considering the operation constraints and the volatility of wind power generation. The model optimizes the total operation costs from energy and heating consumption...... into a mixed-integer programming (MIP) problem. Numerical simulations present the efficacy of the proposed model for day-ahead scheduling of a microgrid with wind penetration under the deregulated environment. © 2011 State Grid Electrtic Resarch Institute Press....

  3. Motion

    CERN Document Server

    Rivera, Andrea

    2017-01-01

    Motion is all around us. Learn how it is used in art, technology, and engineering. Five easy-to-read chapters explain the science behind motion, as well as its real-world applications. Vibrant, full-color photos, bolded glossary words, and a key stats section let readers zoom in even deeper. Aligned to Common Core Standards and correlated to state standards. Abdo Zoom is a division of ABDO.

  4. The Potential of hybrid solar-wind electricity generation in Ghana

    International Nuclear Information System (INIS)

    Tibiru, Ayirewura Vitus

    2013-07-01

    In this work the potential of harnessing electricity from solar and wind sources in Ghana is evaluated both quantitatively and qualitatively. In this regard solar, wind and other relevant data were collected (over a period of one year) from various parts of Ghana. Detailed assessment of the capacity or potential of power production from hybrid solar-wind sources is done with the use of empirical mathematical formulae and the PRO VITUS model incorporated in the 'ENERGY X' software. The various characteristics of wind, solar and available energy resources for the five locations over a one year period have been studied too. The annual mean wind speed at a height of 10 m above ground level for five locations namely Accra, Kumasi, Takoradi, Sunyani and Tamale are 2.38 ms -1 ± 0.05, 2.39 ms -1 ± 0.05, 2.38 ms -1 ± 0.06, 2.18 ms -1 ± 0.05 and 2.47 ± ms -1 respectively and their corresponding annual mean solar radiations are 228.71 Wm -2 ± 9.81, 187.69 Wm -2 ± 9.60, 236.58 Wm -2 ± 10.39, 200.99 Wm -2 ± 9.88 and 231.63 Wm -2 . Thus, the five sites hold potential for hybrid solar-wind energy exploitation. (au)

  5. Optimal Bidding Strategies for Wind Power Producers in the Day-ahead Electricity Market

    Directory of Open Access Journals (Sweden)

    Xiaolin Liu

    2012-11-01

    Full Text Available Wind Power Producers (WPPs seek to maximize profit and minimize the imbalance costs when bidding into the day-ahead market, but uncertainties in the hourly available wind and forecasting errors make the bidding risky. This paper assumes that hourly wind power output given by the forecast follows a normal distribution, and proposes three different bidding strategies, i.e., the expected profit-maximization strategy (EPS, the chance-constrained programming-based strategy (CPS and the multi-objective bidding strategy (ECPS. Analytical solutions under the three strategies are obtained. Comparisons among the three strategies are conducted on a hypothetical wind farm which follows the Spanish market rules. Results show that bid under the EPS is highly dependent on market clearing price, imbalance prices, and also the mean value and standard deviation of wind forecast, and that bid under the CPS is largely driven by risk parameters and the mean value and standard deviation of the wind forecast. The ECPS combining both EPS and CPS tends to choose a compromise bid. Furthermore, the ECPS can effectively control the tradeoff between expected profit and target profit for WPPs operating in volatile electricity markets.

  6. Preliminary Investigation on Generation of Electricity Using Micro Wind Turbines Placed on A Car

    Directory of Open Access Journals (Sweden)

    Yogendra Chaudhary

    2017-03-01

    Full Text Available Wind energy is one of the prominent resources for renewable energy and it is traditionally extracted using stationary wind turbines. However, it can also be extracted using mini or micro wind turbines on a moving body, such as an automobile, while cruising at high speeds on freeways. If the electricity is produced using air flowing around the vehicle without affecting aerodynamic performance of the vehicle, it can be used to charge up the battery or power up additional accessories of the vehicle. For the first time, in the present work, a preliminary investigation was carried out to generate electricity by utilizing air flow on a moving car. Initially, a correlation between the car speed and wind velocity was established using an anemometer. Placing a set of two micro wind turbines along with two micro generators on the rear end of the car trunk, the present study investigated the feasibility of generating electricity from these micro wind turbines while evaluating the effect of drag force on the performance of the car through the experimental approach and computational fluid dynamics (CFD simulations. Both approaches confirmed negligible effect of drag force on the vehicle performance in terms of gas mileage and changes in drag coefficient values. Following these studies, the micro wind turbines were also tested for electricity generation at various cruising speeds of the car ranging from 50 to 80 mph on the freeways. The voltage and power generated always showed an increasing trend with increasing the car speed, however they saturated when a cut off limit was setup with the voltage controllers. A maximum voltage of 3.5 V and a maximum current of 0.8 A were generated by each micro wind turbine when a cut off limit was used along with a load consisting of four LED bulbs in parallel with 3.5 V and 0.2 A rating each. On the other hand, when the tests were repeated without using the cut-off limit, a maximum voltage of 18.91 V and a maximum current

  7. Wind Energy Study and Energy Cost of Wind Electricity Generation in Nigeria: Past and Recent Results and a Case Study for South West Nigeria

    Directory of Open Access Journals (Sweden)

    Oluseyi O. Ajayi

    2014-12-01

    Full Text Available The study assessed the wind energy potential of ten selected sites in the south western region of Nigeria and carried out a cost benefit analysis of wind power generation at those sites. Twenty four years’ (1987 to 2010 wind speed data at 10 m height obtained from the Nigerian meteorological agency were employed to classify the sites wind profiles for electricity generation. The energy cost analysis of generating wind electricity from the sites was also carried out. The outcome showed that sites in Lagos and Oyo States were adequately suited for large scale generation with average wind speeds ranged between 2.9 and 5.8 m/s. Those from other sites may be suitable for small scale generation or as wind farms, with several small turbines connected together, to generate large enough wind power. The turbine matching results shows that turbines cut-in and rated wind speeds of between 2.0 and 3.0 m/s, and between 10 and 12.0 m/s respectively will be very suited to all the sites, particularly those in locations outside Lagos and Oyo States. The energy cost analysis shows that generation cost can be as low as 0.02 €/kWh and as high as 5.03/kWh, depending on the turbine model employed.

  8. An atmospheric turbulence model for spatiotemporal variability of geographically-diverse, aggregated wind-generated electricity to accelerate wide-scale wind energy deployment (Invited)

    Science.gov (United States)

    Lundquist, J. K.; Handschy, M.

    2013-12-01

    During the year 2012, the cumulative wind power capacity installed in the United States could provide roughly 4.4% of electricity demand. Although the wind resource can provide many times over the entire US electrical needs, and costs for onshore wind deployment are continually dropping, the variability of the wind represents one of the greatest remaining barriers to wide-scale wind deployment. This study focuses on the nature of this variability. We quantify the axiom 'geographic diversity reduces variability' (of wind generation) by relating resource variability characteristics to the well-understood physical phenomena of turbulence in the Earth's atmosphere. Many existing studies focus on datasets of a few years' duration in a particular geographic area; such results are difficult to generalize. Our approach builds on the fundamental nonlinear characteristics of turbulence in the atmosphere to characterize wind speed and power generation correlations between wind plants from local to continental scales. The resulting general principles enable estimation of the benefits of geographic aggregation absent detailed site-specific historical data, thereby enabling more efficient transmission grid models, expediting transmission plans, and providing a framework for evaluating the requirements and benefits of electric storage at higher wind penetrations. To validate these general principles, we compare them to observed inter-station correlations in a number of wind-speed data sets, including a 40-year Canadian dataset that spans the continent of North America, as well as shorter-duration datasets in smaller regions within the United States. This presentation will present general rules for the dependence of correlation between wind turbines on separation and time scale. We suggest these general rules could help shift renewable integration planning from simulation towards optimization.

  9. Shipborne Wind Measurement and Motion-induced Error Correction of a Coherent Doppler Lidar over the Yellow Sea in 2014

    Science.gov (United States)

    Zhai, Xiaochun; Wu, Songhua; Liu, Bingyi; Song, Xiaoquan; Yin, Jiaping

    2018-03-01

    Shipborne wind observations by a coherent Doppler lidar (CDL) have been conducted to study the structure of the marine atmospheric boundary layer (MABL) during the 2014 Yellow Sea campaign. This paper evaluates uncertainties associated with the ship motion and presents the correction methodology regarding lidar velocity measurement based on modified 4-Doppler beam swing (DBS) solution. The errors of calibrated measurement, both for the anchored and the cruising shipborne observations, are comparable to those of ground-based measurements. The comparison between the lidar and radiosonde results in a bias of -0.23 ms-1 and a standard deviation of 0.87 ms-1 for the wind speed measurement, and 2.48, 8.84° for the wind direction. The biases of horizontal wind speed and random errors of vertical velocity are also estimated using the error propagation theory and frequency spectrum analysis, respectively. The results show that the biases are mainly related to the measuring error of the ship velocity and lidar pointing error, and the random errors are mainly determined by the signal-to-noise ratio (SNR) of the lidar backscattering spectrum signal. It allows for the retrieval of vertical wind, based on one measurement, with random error below 0.15 ms-1 for an appropriate SNR threshold and bias below 0.02 ms-1. The combination of the CDL attitude correction system and the accurate motion correction process has the potential of continuous long-term high temporal and spatial resolution measurement for the MABL thermodynamic and turbulence process.

  10. Motion of guiding center drift atoms in the electric and magnetic field of a Penning trap

    International Nuclear Information System (INIS)

    Kuzmin, S.G.; O'Neil, T.M.

    2005-01-01

    The ApparaTus for High precision Experiment on Neutral Antimatter and antihydrogen TRAP collaborations have produced antihydrogen atoms by recombination in a cryogenic antiproton-positron plasma. This paper discusses the motion of the weakly bound atoms in the electric and magnetic field of the plasma and trap. The effective electric field in the moving frame of the atom polarizes the atom, and then gradients in the field exert a force on the atom. An approximate equation of motion for the atom center of mass is obtained by averaging over the rapid internal dynamics of the atom. The only remnant of the atom internal dynamics that enters this equation is the polarizability for the atom. This coefficient is evaluated for the weakly bound and strongly magnetized (guiding center drift) atoms understood to be produced in the antihydrogen experiments. Application of the approximate equation of motion shows that the atoms can be trapped radially in the large space charge field near the edge of the positron column. Also, an example is presented for which there is full three-dimensional trapping, not just radial trapping. Even untrapped atoms follow curved trajectories, and such trajectories are discussed for the important class of atoms that reach a field ionization diagnostic. Finally, the critical field for ionization is determined as an upper bound on the range of applicability of the theory

  11. Forecasting and decision-making in electricity markets with focus on wind energy

    DEFF Research Database (Denmark)

    Jónsson, Tryggvi

    by these different characteristics. The thesis presents analyses of how this impact is realised in markets significantly penetrated by wind power. Due to its representation by forecasts in the supply curve, such predictions are used to describe their non-linear influence on the market prices. Methods adequately...... accounting for this effect in models for day-ahead forecasting of the prices are also presented in the thesis. Prompted by the volatile behaviour of electricity markets, considerable focus has been on time-varying and robust parameter estimates. The models derived are all based on well know methods from...... the statistical literature. The stochastic production of wind turbines prompts the need for alternative methods for optimally bidding wind power to day-ahead markets. Such bidding strategies are formulated in this thesis, which utilise the information provided by the market models. Bids that maximise expected...

  12. The electricity market - wind energy after NFFO and in liberalized markets

    International Nuclear Information System (INIS)

    Johns, J.H.

    1997-01-01

    The paper will compare the benefits of leasing and other forms of asset based finance to the wind industry, as compared to conventional sources of finance for both the small and large developer. It will explore the attitudes of specialist and major leasing finance houses to the renewable energy industry in general and wind in particular. To date, leasing has been used more widely in municipal waste projects, although the UK tax regime means that there are also strong advantages to leasing for wind. The paper will examine the sensitivity of sources of leasing and debt finance to possible changes in the electricity markets in the UK, it will identify practical problems to be overcome in applying leasing and provide practical tips to developers. It will also examine some of the issues relevant to firms seeking to participate in overseas markets with the help of UK financiers. (Author)

  13. Rolling scheduling of electric power system with wind power based on improved NNIA algorithm

    Science.gov (United States)

    Xu, Q. S.; Luo, C. J.; Yang, D. J.; Fan, Y. H.; Sang, Z. X.; Lei, H.

    2017-11-01

    This paper puts forth a rolling modification strategy for day-ahead scheduling of electric power system with wind power, which takes the operation cost increment of unit and curtailed wind power of power grid as double modification functions. Additionally, an improved Nondominated Neighbor Immune Algorithm (NNIA) is proposed for solution. The proposed rolling scheduling model has further improved the operation cost of system in the intra-day generation process, enhanced the system’s accommodation capacity of wind power, and modified the key transmission section power flow in a rolling manner to satisfy the security constraint of power grid. The improved NNIA algorithm has defined an antibody preference relation model based on equal incremental rate, regulation deviation constraints and maximum & minimum technical outputs of units. The model can noticeably guide the direction of antibody evolution, and significantly speed up the process of algorithm convergence to final solution, and enhance the local search capability.

  14. EFFECTS OF THE PENETRATION OF WIND POWER IN THE BRAZILIAN ELECTRICITY MARKET

    Directory of Open Access Journals (Sweden)

    Milton M. Herrera

    2016-12-01

    Full Text Available Climate variability has been the main driver for renewables in the Brazilian electricity market. This article analyzes the vulnerabilities of the dependence on hydropower in renewable energy production due to climate variation, as well as wind power penetration in Brazil, given a set of wind industry policies. Despite Brazilian renewable energy increase, the study shows the impact in energy supply in north region, due to the lack of transmission infrastructure. In Brazil, the potential trade-offs between renewables growth, and transmission infrastructure inconsistencies in terms of policy implementation are not yet well analyzed. Simulation results show the potential conflicts between energy policies aimed at increasing the wind power supply and boundaries in transmission infrastructure.

  15. Correlations of mesospheric winds with subtle motion of the Arctic polar vortex

    Directory of Open Access Journals (Sweden)

    Y. Bhattacharya

    2010-01-01

    Full Text Available This paper investigates the relationship between high latitude upper mesospheric winds and the state of the stratospheric polar vortex in the absence of major sudden stratospheric warmings. A ground based Michelson Interferometer stationed at Resolute Bay (74°43' N, 94°58' W in the Canadian High Arctic is used to measure mesopause region neutral winds using the hydroxyl (OH Meinel-band airglow emission (central altitude of ~85 km. These observed winds are compared to analysis winds in the upper stratosphere during November and December of 1995 and 1996; years characterized as cold, stable polar vortex periods. Correlation of mesopause wind speeds with those from the upper stratosphere is found to be significant for the 1996 season when the polar vortex is subtly displaced off its initial location by a strong Aleutian High. These mesopause winds are observed to lead stratospheric winds by approximately two days with increasing (decreasing mesospheric winds predictive of decreasing (increasing stratospheric winds. No statistically significant correlations are found for the 1995 season when there is no such displacement of the polar vortex.

  16. On the electrodynamic explanation of the retrograde motion of the electric arc

    International Nuclear Information System (INIS)

    Hong, J.S.; Allen, J.E.

    1992-01-01

    The retrograde motion of the cathode spot in a transverse magnetic field is one of the more intriguing phenomena of the electric arc. Although the phenomenon has been known for nearly ninety years since its discovery by Stark and has stimulated numerous investigations which result in many models giving explanation from different points of view, there is still no theory that can account both qualitatively and quantitatively for all the observations. Most of the explanations of the retrograde motion involve the study of cathode processes to give the preferential formation of new cathode spots along the retrograde direction. One line of explanation, which is rather different from the others, is based on electrodynamics. In this approach the retrograde motion is treated as an electrodynamic event. The present paper develops the theory suggested by Robson and von Engel. A more complete model is proposed and studied in detail by means of electromagnetic field theory. The results obtained not only show that the retrograde motion can be explained by the electrodynamics, but also confirm that the average current density on the cathode spot must be around the order of 10 12 A/m 2 . Recent studies of spot current density have shown values of this order. (author) 22 refs., 4 figs., 1 tab

  17. Evaluation of the Impact of Wind Generation on the Electricity Market Prices and on the Profitability of New Wind Investments

    Science.gov (United States)

    Pereira, A. J.; Saraiva, J. T.

    2012-10-01

    This paper describes a Dynamic Model of the electricity sector that can be used to simulate the evolution of some key variables on the long term, namely the evolution of the electricity price, of the demand and of the capacity factors of the technologies in the generation mix. This model can be used in different ways and by several agents, for instance to estimate the impact on the electricity price of the increasing presence of renewable power stations, namely using wind power and PV systems. In several countries these stations are paid feed-in tariffs with a fixed price but in some cases this scheme is under discussion and there are opinions that payments determined by the market price are more adequate and would bring fewer costs to final consumers. Such a change has to be carefully evaluated given that the presence of renewable stations bidding at an infra marginal price will affect the price itself. The model described in this paper can be used in a profitable way both by governmental agencies when preparing or studying alternative remuneration schemes to renewable stations or by promoters themselves to get more insight to the profitability of their investments, namely if the fixed feed-in tariffs in force in several countries are changed.

  18. Evaluation of the Impact of Wind Generation on the Electricity Market Prices and on the Profitability of New Wind Investments

    Directory of Open Access Journals (Sweden)

    Saraiva J. T.

    2012-10-01

    Full Text Available This paper describes a Dynamic Model of the electricity sector that can be used to simulate the evolution of some key variables on the long term, namely the evolution of the electricity price, of the demand and of the capacity factors of the technologies in the generation mix. This model can be used in different ways and by several agents, for instance to estimate the impact on the electricity price of the increasing presence of renewable power stations, namely using wind power and PV systems. In several countries these stations are paid feed-in tariffs with a fixed price but in some cases this scheme is under discussion and there are opinions that payments determined by the market price are more adequate and would bring fewer costs to final consumers. Such a change has to be carefully evaluated given that the presence of renewable stations bidding at an infra marginal price will affect the price itself. The model described in this paper can be used in a profitable way both by governmental agencies when preparing or studying alternative remuneration schemes to renewable stations or by promoters themselves to get more insight to the profitability of their investments, namely if the fixed feed-in tariffs in force in several countries are changed.

  19. Simulating price patterns for tradable green certificates to promote electricity generation from wind

    International Nuclear Information System (INIS)

    Ford, Andrew; Vogstad, Klaus; Flynn, Hilary

    2007-01-01

    This article uses computer simulation to anticipate the price dynamics in a market for Tradable Green Certificates (TGCs). These markets have been used in Europe to promote generation of electricity from renewable resources like wind. Similar markets have been proposed in the United States of America (USA) where the certificates are called Renewable Energy Credits (RECs). The certificates are issued to the generating companies for each megawatt-hour of renewable electricity generation. The companies may sell the certificates in a market, and the revenues from certificate sales provide an extra incentive to invest in new generating capacity. Proponents argue that this market-based incentive can be designed to support government mandates for a growing fraction of electricity generation from renewable sources. In the USA, these mandates are set by the states and are known as Renewable Portfolio Standards (RPS). We simulate the price dynamics of a market designed to support an aggressive mandate for wind generation in the northwestern USA. The simulations show that the certificate price climbs rapidly to the cap in the early years after the market opens. Investors then react to these high prices with construction of new wind capacity. After a few years, wind generation meets, and then exceeds the requirement. We show that this pattern appears again and again when the simulations are repeated with wide variations in the estimates of behavioral parameters. We use the model to study the impact of different trading strategies by the wind companies and by the distribution companies. We also study the simulated market response if the USA adopts the carbon allowance market envisioned in The Climate Stewardship Act. The article concludes with recommendations for policy makers involved in TGC market design

  20. Simulating price patterns for tradable green certificates to promote electricity generation from wind

    International Nuclear Information System (INIS)

    Ford, A.

    2007-01-01

    This article uses computer simulation to anticipate the price dynamics in a market for Tradable Green Certificates (TGCs). These markets have been used in Europe to promote generation of electricity from renewable resources like wind. Similar markets have been proposed in the United States of America (USA) where the certificates are called Renewable Energy Credits (RECs). The certificates are issued to the generating companies for each megawatt-hour of renewable electricity generation. The companies may sell the certificates in a market, and the revenues from certificate sales provide an extra incentive to invest in new generating capacity. Proponents argue that this market-based incentive can be designed to support government mandates for a growing fraction of electricity generation from renewable sources. In the USA, these mandates are set by the states and are known as Renewable Portfolio Standards (RPS). We simulate the price dynamics of a market designed to support an aggressive mandate for wind generation in the northwestern USA. The simulations show that the certificate price climbs rapidly to the cap in the early years after the market opens. Investors then react to these high prices with construction of new wind capacity. After a few years, wind generation meets, and then exceeds the requirement. We show that this pattern appears again and again when the simulations are repeated with wide variations in the estimates of behavioral parameters. We use the model to study the impact of different trading strategies by the wind companies and by the distribution companies. We also study the simulated market response if the USA adopts the carbon allowance market envisioned in The Climate Stewardship Act. The article concludes with recommendations for policy makers involved in TGC market design. [Author

  1. Relationship between PC index and interplanetary electric field EKL under actual conditions of varying solar wind

    Science.gov (United States)

    Troshichev, Oleg; Smirnov, Michael

    The PC index was introduced as an indicator of magnetic activity in the polar caps generated by the geoeffective interplanetary electric field E _{KL} determined in accordance with Kan and Lee [1979]. The PC index is calculated basing on magnetic data (δF) from near-pole stations Thule and Vostok with use of the statistically justified coefficients of regression α and β linking the polar cap magnetic disturbance vectors δF with the electric field E _{KL}. As a result, the PC index is defined as a value of the polar cap magnetic disturbance standardized with the intensity of the interplanetary electric field EKL regardless of season, UT and hemisphere. Statistically the appropriate values PC and E _{KL} well correlate, however in concrete situations PC and E _{KL} may be quite differ, because E _{KL} characterizes the state of the solar wind far upstream of the magnetosphere, whereas PC characterizes the energy that entered into magnetosphere, Analysis of consistencies and discrepancies between PC and E _{KL} under conditions of different solar wind parameters was carried for all events with magnetic substorms (N=1798) and magnetic storms (N=203) observed in epoch of maximal solar activity (1998-2001). Thus, the solar wind geoefficiency was estimated by independent indicators, such as AL and Dst indices characterizing magnetic activity within the magnetosphere. The essential attention was given also to geoefficiency of sudden pulses of the solar wind dynamic pressure. The results of the analysis were applied to derive the method to nowcast the magnetosphere state, including estimation of the “model PC, AL and Dst” indices calculated by actual measurement of E _{KL} in the point L1 under conditions of varying solar wind. It is demonstrated that the PC index can be successfully used to monitor space weather and the readiness of the magnetosphere to producing substorm or storm.

  2. Meeting the Electrical Energy Needs of a Residential Building with a Wind-Photovoltaic Hybrid System

    Directory of Open Access Journals (Sweden)

    Mohammad Hosein Mohammadnezami

    2015-03-01

    Full Text Available A complete hybrid system including a photovoltaic cell, a wind turbine, and battery is modeled to determine the best approach for sizing the system to meet the electrical energy needs of a residential building. In evaluating system performance, the city of Tehran is used as a case study. Matlab software is used for analyzing the data and optimizing the system for the given application. Further, the cost of the system design is investigated, and shows that the electrical cost of the hybrid system in Tehran is 0.62 US$/kWh, which is 78% less expensive than a wind turbine system and 34% less expensive than a photovoltaic system.

  3. Comparative Study between Two Market Clearing Schemes in Wind Dominant Electricity Markets

    DEFF Research Database (Denmark)

    Farashbashi-Astaneh, Seyed-Mostafa; Hu, Weihao; Chen, Zhe

    2015-01-01

    High price volatility and excessive price reduction are introduced as two emerging problems in wind dominant electricity markets. In this study, an agent-based simulation methodology is employed to investigate the impact of two pricing mechanisms, uniform and pay-as-bid, on the mentioned problems...... policy maker's concerns regarding mentioned emerging problems in power systems with extremely high percentage of wind power penetration. It is also shown that market efficiency is lower under pay-as-bid scheme. The validity of the proposed methodology is investigated using IEEE 24-bus test system with 33....... According to the proposed agent-based approach, electricity market agents (here generation units) learn from their previous bidding experience to obtain maximum financial. A comparative study is then conducted to investigate the impact of mentioned pricing schemes on price volatility and average price level...

  4. Equivalent circuit and characteristic simulation of a brushless electrically excited synchronous wind power generator

    Science.gov (United States)

    Wang, Hao; Zhang, Fengge; Guan, Tao; Yu, Siyang

    2017-09-01

    A brushless electrically excited synchronous generator (BEESG) with a hybrid rotor is a novel electrically excited synchronous generator. The BEESG proposed in this paper is composed of a conventional stator with two different sets of windings with different pole numbers, and a hybrid rotor with powerful coupling capacity. The pole number of the rotor is different from those of the stator windings. Thus, an analysis method different from that applied to conventional generators should be applied to the BEESG. In view of this problem, the equivalent circuit and electromagnetic torque expression of the BEESG are derived on the basis of electromagnetic relation of the proposed generator. The generator is simulated and tested experimentally using the established equivalent circuit model. The experimental and simulation data are then analyzed and compared. Results show the validity of the equivalent circuit model.

  5. Assessment of wind energy potential and cost estimation of wind-generated electricity at hilltops surrounding the city of Maroua in Cameroon

    Science.gov (United States)

    Kaoga, Dieudonné Kidmo; Bogno, Bachirou; Aillerie, Michel; Raidandi, Danwe; Yamigno, Serge Doka; Hamandjoda, Oumarou; Tibi, Beda

    2016-07-01

    In this work, 28 years of wind data, measured at 10m above ground level (AGL), from Maroua meteorological station is utilized to assess the potential of wind energy at exposed ridges tops of mountains surrounding the city of Maroua. The aim of this study is to estimate the cost of wind-generated electricity using six types of wind turbines (50 to 2000 kW). The Weibull distribution function is employed to estimate Weibull shape and scale parameters using the energy pattern factor method. The considered wind shear model to extrapolate Weibull parameters and wind profiles is the empirical power law correlation. The results show that hilltops in the range of 150-350m AGL in increments of 50, fall under Class 3 or greater of the international system of wind classification and are deemed suitable to outstanding for wind turbine applications. A performance of the selected wind turbines is examined as well as the costs of wind-generated electricity at the considered hilltops. The results establish that the lowest costs per kWh are obtained using YDF-1500-87 (1500 kW) turbine while the highest costs are delivered by P-25-100 (90 kW). The lowest costs (US) per kWh of electricity generated are found to vary between a minimum of 0.0294 at hilltops 350m AGL and a maximum of 0.0366 at hilltops 150m AGL, with corresponding energy outputs that are 6,125 and 4,932 MWh, respectively. Additionally, the matching capacity factors values are 38.05% at hilltops 150m AGL and 47.26% at hilltops 350m AGL. Furthermore, YDF-1500-87 followed by Enercon E82-2000 (2000 kW) wind turbines provide the lowest cost of wind generated electricity and are recommended for use for large communities. Medium wind turbine P-15-50 (50 kW), despite showing the best coefficients factors (39.29% and 48.85% at hilltops 150 and 350m AGL, in that order), generates electricity at an average higher cost/kWh of US0.0547 and 0.0440 at hilltops 150 and 350m AGL, respectively. P-15-50 is deemed a more advantageous option

  6. Analysing the impact of renewable electricity support schemes on power prices: The case of wind electricity in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Saenz de Miera, Gonzalo [Department of Public Economics, Universidad Autonoma de Madrid, Campus de Cantoblanco, Madrid 28049 (Spain); del Rio Gonzalez, Pablo [Institute for Public Policies, Centro de Ciencias Humanas y Sociales, CSIC, C/Albasanz 26-28, 28037 Madrid (Spain); Vizcaino, Ignacio [Iberdrola, C/Tomas Redondo, 1, Madrid 28033 (Spain)

    2008-09-15

    It is sometimes argued that renewables are 'expensive'. However, although it is generally true that the private costs of renewable electricity generation are certainly above those of conventional electricity, that statement fails to consider the social benefits provided by electricity from renewable energy sources (RES-E), including environmental and socioeconomic ones. This paper empirically analyses an additional albeit usually neglected benefit: the reduction in the wholesale price of electricity as a result of more RES-E generation being fed into the grid. The case of wind generation in Spain shows that this reduction is greater than the increase in the costs for the consumers arising from the RES-E support scheme (the feed-in tariffs), which are charged to the final consumer. Therefore, a net reduction in the retail electricity price results, which is positive from a consumer point of view. This provides an additional argument for RES-E support and contradicts one of the usual arguments against RES-E deployment: the excessive burden on the consumer. (author)

  7. Analysing the impact of renewable electricity support schemes on power prices: The case of wind electricity in Spain

    International Nuclear Information System (INIS)

    Saenz de Miera, Gonzalo; del Rio Gonzalez, Pablo; Vizcaino, Ignacio

    2008-01-01

    It is sometimes argued that renewables are 'expensive'. However, although it is generally true that the private costs of renewable electricity generation are certainly above those of conventional electricity, that statement fails to consider the social benefits provided by electricity from renewable energy sources (RES-E), including environmental and socioeconomic ones. This paper empirically analyses an additional albeit usually neglected benefit: the reduction in the wholesale price of electricity as a result of more RES-E generation being fed into the grid. The case of wind generation in Spain shows that this reduction is greater than the increase in the costs for the consumers arising from the RES-E support scheme (the feed-in tariffs), which are charged to the final consumer. Therefore, a net reduction in the retail electricity price results, which is positive from a consumer point of view. This provides an additional argument for RES-E support and contradicts one of the usual arguments against RES-E deployment: the excessive burden on the consumer. (author)

  8. Preliminary Assessment of Plug-in Hybrid Electric Vehicles on Wind Energy Markets

    Energy Technology Data Exchange (ETDEWEB)

    Short, W.; Denholm, P.

    2006-04-01

    This report examines a measure that may potentially reduce oil use and also more than proportionately reduce carbon emissions from vehicles. The authors present a very preliminary analysis of plug-in hybrid electric vehicles (PHEVs) that can be charged from or discharged to the grid. These vehicles have the potential to reduce gasoline consumption and carbon emissions from vehicles, as well as improve the viability of renewable energy technologies with variable resource availability. This paper is an assessment of the synergisms between plug-in hybrid electric vehicles and wind energy. The authors examine two bounding cases that illuminate this potential synergism.

  9. Electric vehicles in Danish power system with large penetration of wind power

    DEFF Research Database (Denmark)

    Yang, Lihui; Xu, Zhao; Østergaard, Jacob

    2011-01-01

    Electric vehicles (EVs) provide a unique opportunity for reducing the CO2 emissions from the transport sector. At the same time, EVs have the potential to play an important role in the economical and reliable operation of an electricity system with high penetration of renewable energy. An analysis...... initiatives of the recently established EDISON program are described. Moreover, the latest development of the EDISON program is treated, that is, EDISON as a research consortium to design a new model for the Danish power system with high penetration of wind power and EVs with vehicle to grid (V2G...

  10. Enhancing the smoothness of joint motion induced by functional electrical stimulation using co-activation strategies

    Directory of Open Access Journals (Sweden)

    Ruppel Mirjana

    2017-09-01

    Full Text Available The motor precision of today’s neuroprosthetic devices that use artificial generation of limb motion using Functional Electrical Stimulation (FES is generally low. We investigate the adoption of natural co-activation strategies as present in antagonistic muscle pairs aiming to improve motor precision produced by FES. In a test in which artificial knee-joint movements were generated, we could improve the smoothness of FES-induced motion by 513% when applying co-activation during the phases in which torque production is switched between muscles – compared to no co-activation. We further demonstrated how the co-activation level influences the joint stiffness in a pendulum test.

  11. Integration of plug-in hybrid electric vehicles in a regional wind-thermal power system

    International Nuclear Information System (INIS)

    Goeransson, Lisa; Karlsson, Sten; Johnsson, Filip

    2010-01-01

    This study investigates consequences of integrating plug-in hybrid electric vehicles (PHEVs) in a wind-thermal power system supplied by one quarter of wind power and three quarters of thermal generation. Four different PHEV integration strategies, with different impacts on the total electric load profile, have been investigated. The study shows that PHEVs can reduce the CO 2 -emissions from the power system if actively integrated, whereas a passive approach to PHEV integration (i.e. letting people charge the car at will) is likely to result in an increase in emissions compared to a power system without PHEV load. The reduction in emissions under active PHEV integration strategies is due to a reduction in emissions related to thermal plant start-ups and part load operation. Emissions of the power sector are reduced with up to 4.7% compared to a system without PHEVs, according to the simulations. Allocating this emission reduction to the PHEV electricity consumption only, and assuming that the vehicles in electric mode is about 3 times as energy efficient as standard gasoline operation, total emissions from PHEVs would be less than half the emissions of a standard car, when running in electric mode.

  12. Substitution of critical raw materials in low-carbon technologies: lighting, wind turbines and electric vehicles

    OpenAIRE

    PAVEL CLAUDIU; MARMIER Alain; ALVES DIAS PATRICIA; BLAGOEVA Darina; TZIMAS Evangelos; SCHULER Doris; SCHLEICHER Tobias; JENSEIT Wolfgang; DEGREIF Stefanie; BUCHERT Matthias

    2016-01-01

    This report evaluates the substitution options of nine critical raw materials (CRM) (Eu, Tb, Y, In, Ga, Ge Nd, Pr and Dy) required in lighting, wind turbines and electric vehicles applications. Substitution has been considered from many perspectives from reducing the use of CRM via improved material efficiency to substitution at material and component level. Despite of many years of research, a direct and complete replacement of the critical raw materials in phosphors, LEDs and permanent ...

  13. MEASUREMENT OF MOTION CORRECTED WIND VELOCITY USING AN AEROSTAT LOFTED SONIC ANEMOMETER

    Science.gov (United States)

    An aerostat-lofted, sonic anemometer was used to determine instantaneous 3 dimensional wind velocities at altitudes relevant to fire plume dispersion modeling. An integrated GPS, inertial measurement unit, and attitude heading and reference system corrected the wind data for th...

  14. Design of an Electric Commutated Frog-Leg Winding Permanent-Magnet DC Machine

    Directory of Open Access Journals (Sweden)

    Hang Zhang

    2014-03-01

    Full Text Available An electric commutated frog-leg winding permanent-magnet (PM DC machine is proposed in this paper. It has a semi-closed slotted stator with a classical type of mesh winding introduced from the conventional brushed DC machine and a polyphase electric commutation besides a PM excitation rotor and a circular arrayed Hall position sensor. Under the cooperation between the position sensor and the electric commutation, the proposed machine is basically operated on the same principle of the brushed one. Because of its simplex frog-leg winding, the combination between poles and slots is designed as 4/22, and the number of phases is set as 11. By applying an exact analytical method, which is verified comparable with the finite element analyses (FEA, to the prediction of its instantaneous magnetic field, electromotive force (EMF, cogging torque and output torque, it is well designed with a series of parameters in dimension aiming at the lowest cogging torque. A 230 W, 4-pole, and 22-slot new machine is prototyped and tested to verify the analysis.

  15. Analysis of the imbalance price scheme in the Spanish electricity market: A wind power test case

    International Nuclear Information System (INIS)

    Bueno-Lorenzo, Miriam; Moreno, M. Ángeles; Usaola, Julio

    2013-01-01

    This work investigates the interaction between wind power and electricity markets. The paper is focused on balancing markets pricing policies. The proposal of a new imbalance price scheme is included and conveniently evaluated. This proposed scheme tries to minimise the use of ancillary services to compensate for deviations in searching for a more efficient market design. The effectiveness of imbalance prices as market signals is also examined, and policy recommendations regarding imbalance services are discussed. Two test cases are included that analyse the participation of a wind power producer in the Spanish electricity market using a stochastic optimisation strategy. For this purpose, the uncertainty of the variables is considered, i.e., wind power production and prediction, intraday and imbalance prices. Test cases were run with real data for 10 months, and realistic results are presented along with a hypothetical test case. The regulation of the imbalance prices may not be adequate for the Spanish electricity market because an error drop is not sufficiently encouraged. Therefore, we suggest the application of a new imbalance price scheme, which includes an additional constraint. The conclusions of this paper can be assumed to be general policy recommendations

  16. Integrated analysis of DFIG drive-train and power electronics dynamics during electrical AC faults and wind disturbances

    DEFF Research Database (Denmark)

    Barahona Garzón, Braulio; Sørensen, Poul Ejnar; Anaya-Lara, Olimpo

    2013-01-01

    The dynamics of a 2 MW DFIG wind turbine are studied during electrical AC faults, and wind disturbances. A simulation platform that couples HAWC2, and Matlab/Simulink was used. High frequencies of the gear box, and power electronics are neglected. It was shown that the dynamics of the dc......-link are influenced by turbulence, and wind gusts. An AC fault that triggers protection systems was simulated, and the influence on the dc-link voltage, shaft and tower loading illustrated....

  17. The impact of Production Tax Credits on the profitable production of electricity from wind in the U.S

    International Nuclear Information System (INIS)

    Xi Lu; Tchou, Jeremy; McElroy, Michael B.; Nielsen, Chris P.

    2011-01-01

    A spatial financial model using wind data derived from assimilated meteorological condition was developed to investigate the profitability and competitiveness of onshore wind power in the contiguous U.S. It considers not only the resulting estimated capacity factors for hypothetical wind farms but also the geographically differentiated costs of local grid connection. The levelized cost of wind-generated electricity for the contiguous U.S. is evaluated assuming subsidy levels from the Production Tax Credit (PTC) varying from 0 to 4 cents /kWh under three cost scenarios: a reference case, a high cost case, and a low cost case. The analysis indicates that in the reference scenario, current PTC subsidies of 2.1 cents /kWh are at a critical level in determining the competitiveness of wind-generated electricity compared to conventional power generation in local power market. Results from this study suggest that the potential for profitable wind power with the current PTC subsidy amounts to more than seven times existing demand for electricity in the entire U.S. Understanding the challenges involved in scaling up wind energy requires further study of the external costs associated with improvement of the backbone transmission network and integration into the power grid of the variable electricity generated from wind. - Highlights: → Wind power competitiveness is driven by meteorology and proximity to the grid. → We spatially model U.S. onshore wind under ranges of subsidies and costs. → Wind power is competitive at a PTC subsidy of 2.1 cents/kWh. → Under current PTC levels, profitable wind potential far exceeds U.S. power demand.

  18. Wind power development in the United States: Effects of policies and electricity transmission congestion

    Science.gov (United States)

    Hitaj, Claudia

    In this dissertation, I analyze the drivers of wind power development in the United States as well as the relationship between renewable power plant location and transmission congestion and emissions levels. I first examine the role of government renewable energy incentives and access to the electricity grid on investment in wind power plants across counties from 1998-2007. The results indicate that the federal production tax credit, state-level sales tax credit and production incentives play an important role in promoting wind power. In addition, higher wind power penetration levels can be achieved by bringing more parts of the electricity transmission grid under independent system operator regulation. I conclude that state and federal government policies play a significant role in wind power development both by providing financial support and by improving physical and procedural access to the electricity grid. Second, I examine the effect of renewable power plant location on electricity transmission congestion levels and system-wide emissions levels in a theoretical model and a simulation study. A new renewable plant takes the effect of congestion on its own output into account, but ignores the effect of its marginal contribution to congestion on output from existing plants, which results in curtailment of renewable power. Though pricing congestion removes the externality and reduces curtailment, I find that in the absence of a price on emissions, pricing congestion may in some cases actually increase system-wide emissions. The final part of my dissertation deals with an econometric issue that emerged from the empirical analysis of the drivers of wind power. I study the effect of the degree of censoring on random-effects Tobit estimates in finite sample with a particular focus on severe censoring, when the percentage of uncensored observations reaches 1 to 5 percent. The results show that the Tobit model performs well even at 5 percent uncensored observations

  19. Capacities and Limitations of Wind Tunnel Physical Experiments on Motion and Dispersion of Different Density Gas Pollutants

    Science.gov (United States)

    Zavila, Ondřej; Blejchař, Tomáš

    2017-04-01

    The article focuses on the analysis of the possibilities to model motion and dispersion of plumes of different density gas pollutants in lowspeed wind tunnels based on the application of physical similarity criteria, in this case the Froude number. The analysis of the physical nature of the modeled process by the Froude number is focused on the influence of air flow velocity, gas pollutant density and model scale. This gives an idea of limitations for this type of physical experiments in relation to the modeled real phenomena. The resulting statements and logical links are exemplified by a CFD numerical simulation of a given task calculated in ANSYS Fluent software.

  20. Wind power merit-order and feed-in-tariffs effect: A variability analysis of the Spanish electricity market

    International Nuclear Information System (INIS)

    Azofra, D.; Jiménez, E.; Martínez, E.; Blanco, J.; Saenz-Díez, J.C.

    2014-01-01

    Highlights: • M5P algorithm-based model determines influence of wind power on Spanish spot market. • Assessment of the wind power influence for different levels of wind resource. • Cost-benefit analysis is developed, accounting feed-in-tariffs and merit order effect. • The worst and best levels of wind power production for the system are determined. - Abstract: The incipient large-scale energy-storage technologies are not sufficiently developed yet, which means that the wind power production depends on the wind speed at every moment. This, along with the fact that the wind resource is not constant over time, makes wind power production quite variable. Therefore, an artificial intelligence-based technique (M5P algorithm) is applied to empirical hourly data to determine the influence of wind power technology on the spot market for different levels of wind resource in 2012. It concludes that wind power depressed the spot prices between 7.42 and 10.94 €/MW h for a wind power production of 90% and 110% of the real one, respectively. Furthermore, taking into account the important presence of wind power in the Spanish generation mix, the above range has been extended up to 0% in order to determine the worst and best level of wind power production for the Spanish electrical system (from an economical point of view). To do so, both feed-in-tariffs and wind power impact on spot market (merit order effect) have been accounted in accordance with the different levels of wind power production. Since empirical data from 2012 have been used to conduct the research, the results presented in this paper may provide policy makers with a worst and best-case scenario to discuss about the convenience of the last cutting expenses over wind power technology in Spain

  1. Photo-induced morphological winding and unwinding motion of nanoscrolls composed of niobate nanosheets with a polyfluoroalkyl azobenzene derivative

    Science.gov (United States)

    Nabetani, Yu; Takamura, Hazuki; Uchikoshi, Akino; Hassan, Syed Zahid; Shimada, Tetsuya; Takagi, Shinsuke; Tachibana, Hiroshi; Masui, Dai; Tong, Zhiwei; Inoue, Haruo

    2016-06-01

    Photo-responsive nanoscrolls can be successfully fabricated by mixing a polyfluoroalkyl azobenzene derivative and a niobate nanosheet, which is exfoliated from potassium hexaniobate. In this study, we have found that the photo-responsive nanoscroll shows a morphological motion of winding and unwinding, which is basically due to the nanosheet sliding within the nanoscroll, by efficient photo-isomerization reactions of the intercalated azobenzene in addition to the interlayer distance change of the nanoscrolls. The relative nanosheet sliding of the nanoscroll is estimated to be ca. 280 nm from the AFM morphology analysis. The distance of the sliding motion is over 20 times that of the averaged nanosheet sliding in the azobenzene/niobate hybrid film reported previously. Photo-responsive nanoscrolls can be expected to be novel photo-activated actuators and artificial muscle model materials.Photo-responsive nanoscrolls can be successfully fabricated by mixing a polyfluoroalkyl azobenzene derivative and a niobate nanosheet, which is exfoliated from potassium hexaniobate. In this study, we have found that the photo-responsive nanoscroll shows a morphological motion of winding and unwinding, which is basically due to the nanosheet sliding within the nanoscroll, by efficient photo-isomerization reactions of the intercalated azobenzene in addition to the interlayer distance change of the nanoscrolls. The relative nanosheet sliding of the nanoscroll is estimated to be ca. 280 nm from the AFM morphology analysis. The distance of the sliding motion is over 20 times that of the averaged nanosheet sliding in the azobenzene/niobate hybrid film reported previously. Photo-responsive nanoscrolls can be expected to be novel photo-activated actuators and artificial muscle model materials. Electronic supplementary information (ESI) available: Fig. S1. Photo-isomerization reaction of nanoscrolls. See DOI: 10.1039/c6nr02177h

  2. Large-scale offshore wind energy. Cost analysis and integration in the Dutch electricity market

    International Nuclear Information System (INIS)

    De Noord, M.

    1999-02-01

    The results of analysis of the construction and integration costs of large-scale offshore wind energy (OWE) farms in 2010 are presented. The integration of these farms (1 and 5 GW) in the Dutch electricity distribution system have been regarded against the background of a liberalised electricity market. A first step is taken for the determination of costs involved in solving integration problems. Three different types of foundations are examined: the mono-pile, the jacket and a new type of foundation: the concrete caisson pile: all single-turbine-single-support structures. For real offshore applications (>10 km offshore, at sea-depths >20 m), the concrete caisson pile is regarded as the most suitable. The price/power ratios of wind turbines are analysed. It is assumed that in 2010 turbines in the power range of 3-5 MW are available. The main calculations have been conducted for a 3 MW turbine. The main choice in electrical infrastructure is for AC or DC. Calculations show that at distances of 30 km offshore and more, the use of HVDC will result in higher initial costs but lower operating costs. The share of operating and maintenance (O ampersand M) costs in the kWh cost price is approximately 3.3%. To be able to compare the two farms, a base case is derived with a construction time of 10 years for both. The energy yield is calculated for a wind regime offshore of 9.0 m/s annual mean wind speed. Per 3 MW turbine this results in an annual energy production of approximately 12 GWh. The total farm efficiency amounts to 82%, resulting in a total farm capacity factor of 38%. With a required internal rate of return of 15%, the kWh cost price amounts to 0.24 DFl and 0.21 DFl for the 1 GW and 5 GW farms respectively in the base case. The required internal rate of return has a large effect on the kWh cost price, followed by costs of subsystems. O ampersand M costs have little effect on the cost price. Parameter studies show that a small cost reduction of 5% is possible when

  3. The intermittency of wind, solar, and renewable electricity generators. Technical barrier or rhetorical excuse?

    Energy Technology Data Exchange (ETDEWEB)

    Sovacool, Benjamin K. [Centre on Asia and Globalisation, Lee Kuan Yew School of Public Policy, National University of Singapore, 469C Bukit Timah Road, Singapore 259772 (Singapore)

    2009-09-15

    A consensus has long existed within the electric utility sector of the United States that renewable electricity generators such as wind and solar are unreliable and intermittent to a degree that they will never be able to contribute significantly to electric utility supply or provide baseload power. This paper asks three interconnected questions: (1) What do energy experts really think about renewables in the United States?; (2) To what degree are conventional baseload units reliable?; (3) Is intermittency a justifiable reason to reject renewable electricity resources? To provide at least a few answers, the author conducted 62 formal, semi-structured interviews at 45 different institutions including electric utilities, regulatory agencies, interest groups, energy systems manufacturers, nonprofit organizations, energy consulting firms, universities, national laboratories, and state institutions in the United States. In addition, an extensive literature review of government reports, technical briefs, and journal articles was conducted to understand how other countries have dealt with (or failed to deal with) the intermittent nature of renewable resources around the world. It was concluded that the intermittency of renewables can be predicted, managed, and mitigated, and that the current technical barriers are mainly due to the social, political, and practical inertia of the traditional electricity generation system. (author)

  4. Wind energy for electricity generation; Generacion electrica con energia del viento

    Energy Technology Data Exchange (ETDEWEB)

    Huacuz Villamar, Jorge M.; Borja Diaz, Marco Antonio R. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-09-01

    A description is made of electricity generation utilizing wind energy (Eoloelectric Generation). The case of Mexico is reviewed in respect to this technology, mentioning a small power plant of 1.5 Megawatts installed by the Comision Federal de Electricidad in the zone of La Ventosa in the State of Oaxaca. Mention is made of the possible causes why Mexico has not advanced in this type of power plants for power generation as in other countries like Germany, Spain and India. The advance in these countries is shown as well as the growth statistics of the wind power in the world. It is concluded that there is not in Mexico a strategy for wind energy utilization for electricity generation in spite of the potential benefits this technology offers [Espanol] Se describe el caso de la generacion electrica utilizando la energia del viento (Generacion Eoloelectrica). Se aborda el caso de Mexico respecto a esta tecnologia, mencionando una pequena central de 1.5 Megawatts (MW) instalada por la Comision Federal de Electricidad (CFE) en la zona de la Ventosa, Oaxaca. Se mencionan las posibles causas por las que en Mexico este tipo de centrales de generacion de energia no ha avanzado como en otros paises, por ejemplo: Alemania, Espana y la India. Se muestran los avances de estos paises, asi como una estadistica del crecimiento de la generacion eoloelectrica en el mundo. Se concluye en que no existe en Mexico una estrategia para la generacion eoloelectrica a pesar de los beneficios potenciales que ofrece esta tecnologia

  5. Investigation of value and costs of wind energy in the electric system. Report - Final meeting, Paris, 30 January 2013

    International Nuclear Information System (INIS)

    2013-01-01

    This document contains five Power Point presentations which respectively address: the values and costs of wind energy in the electric system (economic assessment of wind energy in the French electric system), the analysis principles and methods (economic assessment and comparison of two scenarios defined by six different parameters: consumption, energy price, wind energy deployment, evolution of the nuclear fleet, nuclear load factor, potential of demand side management), the analysis of the energy substitution value, the value analysis of the peak management, and the impact on infrastructures and system services

  6. Neutral winds and electric fields in the dust auroral oval. II - Theory and model

    Science.gov (United States)

    Mikkelsen, I. S.; Jorgensen, T. S.; Kelley, M. C.; Larsen, M. F.; Pereira, E.

    1981-01-01

    A two-dimensional numerical model of the thermosphere is applied to the auroral zone neutral wind, electric field, and plasma density data set, presented in an earlier paper. The model shows that the action of the Lorentz force can be responsible to a great extent for the large zonal velocities near the 150-km altitude. Model equations are described, an explanation of the use of the geophysical conditions is given, and model integrations are compared to the wind measurements. However, for the two-dimensional model to be effective, the atmosphere must not cross too many meridians of local time during the integration period, so that the background state should remain fairly uniform. It is concluded that the two-dimensional model cannot accurately explain the details of the wind profiles because of the three-dimensional character of the physical situation. Thus it is noted that the observed winds were part of a large-scale three-dimensional flow which is only weakly coupled to short-term variations in magnetospheric conditions.

  7. US East Coast offshore wind energy resources and their relationship to time-varying electricity demand

    Science.gov (United States)

    Dvorak, M. J.; Corcoran, B. A.; Ten Hoeve, J. E.; Jacobson, M. Z.; McIntyre, N.

    2011-12-01

    This study characterizes the annual-mean US East Coast (USEC) offshore wind energy (OWE) resource based on 5 years of skillful, high resolution mesoscale model (WRF-ARW) results at the turbine hub height of 90 m. Model output was validated buoys and offshore towers, which provides insight into the relative errors of forecasting winds in the region. The most suitable locations for OWE are prescribed, based on their wind resource, shallow bathymetry, low hurricane risk, and peak-power generation potential. The offshore region from Maine to Virginia was found to have exceptional overall resource the best wind resource, shallow water, and low hurricane risk. The region east of Long Island, NY to Cape Cod, MA has the best summertime peak resource, due to regional upwelling that often strengthens the sea breeze. Overall, the resource from Maine to Florida out to 200-m depth, using turbine capacity factor cutoffs of 45% and 40% is between 1175-1672 TWh (134-191 GW avg.). Between 30-42% of the electricity demand for the entire US (2009) could be provided using USEC OWE alone and 93-133% of Maine to Florida (2008) demand.

  8. Wind Power Development and Energy Storage under China’s Electricity Market Reform—A Case Study of Fujian Province

    Directory of Open Access Journals (Sweden)

    Dunguo Mou

    2018-01-01

    Full Text Available This paper, based on the Fujian provincial 500 kV grid and part of the 220 kV grid and the key power plants, including hydro, coal, nuclear, gas, wind and pumping and storage hydro powers (PSHP connected to the grid, constructs an independent electricity market model. Using data that are very close to reality about coal fired power production costs, along with data about power plants’ technical constraints, this paper studies the effect of wind power on Fujian’s provincial electricity market. Firstly, the paper analyzes the relationship between wind speed and wind power output and the effects of short-term power output fluctuation on frequency modulation and voltage regulation. Secondly, under supposition of the production costs following quadratic functions, the paper analyzes the effects of changes in wind power output on the electricity supply costs under optimal power flow. Thirdly, using the bidding model in the Australian Electricity Market Operator for reference and supposing that, in a competitive market, coal fired power plants can bid 6 price bands according to their capacity, the paper analyzes effects of wind power on electricity prices under optimal power flow, the stabilizing effects of PSHP and the minimum PSHP capacity needed to stabilize the electricity market. Finally, using a daily load curve, this paper simulates the electricity prices’ fluctuation under optimal power flow and PSHP’s stabilizing effect. The results show that, although PSHP has a large external social welfare effect, it can hardly make a profit. In the end, this paper puts forward some policy suggestions for Fujian province’s wind and nuclear power development, PSHP construction and electricity market development.

  9. Method for selecting parameters and assessing efficiency of wind-diesel power plants for autonomous electrical supply systems

    Science.gov (United States)

    Obukhov, S. G.; Plotnikov, I. A.; Masolov, V. G.

    2018-01-01

    The article presents an original technique for selecting parameters and evaluating the efficiency of wind-diesel power plants for isolated power supply systems. The initial data to perform energy calculations are simulation models of electric load and wind speed. The load is simulated using typical schedules of electric loads of a decentralized consumer, taking into account a random component for each hour of the day. To create a simulation model of the wind, a typical climatic series of wind speeds at a prospective site of the power plant has been constructed according to the data of long-term meteorological observations. The proposed technique was verified through the example of choosing a wind-diesel power plant for the village of Ust-Olenyok of the Republic of Sakha (Yakutia).

  10. Novel wind powered electric vehicle charging station with vehicle-to-grid (V2G) connection capability

    International Nuclear Information System (INIS)

    Fathabadi, Hassan

    2017-01-01

    Highlights: • The only wind powered EV charging station reported in the literature. • The charging station maximally converts wind energy into electric energy. • Novel fast and highly accurate MPPT technique implemented in the EV charging station. • The charging station is grid-connected type with vehicle-to-grid (V2G) technology. • The charging station balances load demand in the grid connected to it. - Abstract: In this study, a novel grid-connected wind powered electric vehicle (EV) charging station with vehicle-to-grid (V2G) technology is designed and constructed. The wind powered EV charging station consists of a wind energy conversion system (WECS), a unidirectional DC/DC converter connected to the WECS, a maximum power point tracking (MPPT) controller, 15 bidirectional DC/DC converters dedicated to 15 charging stations provided for charging EVs, and a three-phase bidirectional DC/AC inverter connected to the grid. The contribution of this work is that the grid-connected wind powered EV charging station presented in this work is the only constructed EV charging station reported in the literature that uses wind energy as a renewable resource to produce electric energy for charging EVs, and moreover, it maximally converts wind energy into electric energy because it uses a novel fast and highly accurate MPPT technique proposed in this study. Other works are only simulated models without any new MPPT consideration. It is demonstrated that the constructed wind powered EV charging station is a perfect charging station that not only produces electric energy to charge EVs but also balances load demand in the grid connected to it.

  11. NASA's GMAO Atmospheric Motion Vectors Simulator: Description and Application to the MISTiC Winds Concept

    Science.gov (United States)

    Carvalho, David; McCarty, Will; Errico, Ron; Prive, Nikki

    2018-01-01

    An atmospheric wind vectors (AMVs) simulator was developed by NASA's GMAO to simulate observations from future satellite constellation concepts. The synthetic AMVs can then be used in OSSEs to estimate and quantify the potential added value of new observations to the present Earth observing system and, ultimately, the expected impact on the current weather forecasting skill. The GMAO AMV simulator is a tunable and flexible computer code that is able to simulate AMVs expected to be derived from different instruments and satellite orbit configurations. As a case study and example of the usefulness of this tool, the GMAO AMV simulator was used to simulate AMVs envisioned to be provided by the MISTiC Winds, a NASA mission concept consisting of a constellation of satellites equipped with infrared spectral midwave spectrometers, expected to provide high spatial and temporal resolution temperature and humidity soundings of the troposphere that can be used to derive AMVs from the tracking of clouds and water vapor features. The GMAO AMV simulator identifies trackable clouds and water vapor features in the G5NR and employs a probabilistic function to draw a subset of the identified trackable features. Before the simulator is applied to the MISTiC Winds concept, the simulator was calibrated to yield realistic observations counts and spatial distributions and validated considering as a proxy instrument to the MISTiC Winds the Himawari-8 Advanced Imager (AHI). The simulated AHI AMVs showed a close match with the real AHI AMVs in terms of observation counts and spatial distributions, showing that the GMAO AMVs simulator synthesizes AMVs observations with enough quality and realism to produce a response from the DAS equivalent to the one produced with real observations. When applied to the MISTiC Winds scanning points, it can be expected that the MISTiC Winds will be able to collect approximately 60,000 wind observations every 6 hours, if considering a constellation composed of

  12. Power converter with maximum power point tracking MPPT for small wind-electric pumping systems

    International Nuclear Information System (INIS)

    Lara, David; Merino, Gabriel; Salazar, Lautaro

    2015-01-01

    Highlights: • We implement a wind electric pumping system of small power. • The power converter allowed to change the operating point of the electro pump. • Two control techniques were implemented in the power converter. • The control V/f variable allowed to increase the power generated by the permanent magnet generator. - Abstract: In this work, an AC–DC–AC direct-drive power converter was implemented for a wind electric pumping system consisting of a permanent magnet generator (PMG) of 1.3 kW and a peripheral single phase pump of 0.74 kW. In addition, the inverter linear V/f control scheme and the maximum power point tracking (MPPT) algorithm with variable V/f were developed. MPPT algorithm seeks to extract water in a wide range of power input using the maximum amount of wind power available. Experimental trials at different pump pressures were conducted. With a MPPT tracking system with variable V/f, a power value of 1.3 kW was obtained at a speed of 350 rpm and a maximum operating hydraulic head of 50 m. At lower operating heads pressures (between 10 and 40 m), variable V/f control increases the power generated by the PMG compared to the linear V/f control. This increase ranged between 4% and 23% depending on the operating pressure, with an average of 13%, getting close to the maximum electrical power curve of the PMG. The pump was driven at variable frequency reaching a minimum speed of 0.5 times the rated speed. Efficiency of the power converter ranges between 70% and 95% with a power factor between 0.4 and 0.85, depending on the operating pressure

  13. A Biological Micro Actuator: Graded and Closed-Loop Control of Insect Leg Motion by Electrical Stimulation of Muscles

    OpenAIRE

    Cao, Feng; Zhang, Chao; Vo Doan, Tat Thang; Li, Yao; Sangi, Daniyal Haider; Koh, Jie Sheng; Huynh, Ngoc Anh; Aziz, Mohamed Fareez Bin; Choo, Hao Yu; Ikeda, Kazuo; Abbeel, Pieter; Maharbiz, Michel M.; Sato, Hirotaka

    2014-01-01

    In this study, a biological microactuator was demonstrated by closed-loop motion control of the front leg of an insect (Mecynorrhina torquata, beetle) via electrical stimulation of the leg muscles. The three antagonistic pairs of muscle groups in the front leg enabled the actuator to have three degrees of freedom: protraction/retraction, levation/depression, and extension/flexion. We observed that the threshold amplitude (voltage) required to elicit leg motions was approximately 1.0 V; thus, ...

  14. Dynamic Analysis of Electrical Power Grid Delivery: Using Prime Mover Engines to Balance Dynamic Wind Turbine Output

    Energy Technology Data Exchange (ETDEWEB)

    Diana K. Grauer

    2011-10-01

    This paper presents an investigation into integrated wind + combustion engine high penetration electrical generation systems. Renewable generation systems are now a reality of electrical transmission. Unfortunately, many of these renewable energy supplies are stochastic and highly dynamic. Conversely, the existing national grid has been designed for steady state operation. The research team has developed an algorithm to investigate the feasibility and relative capability of a reciprocating internal combustion engine to directly integrate with wind generation in a tightly coupled Hybrid Energy System. Utilizing the Idaho National Laboratory developed Phoenix Model Integration Platform, the research team has coupled demand data with wind turbine generation data and the Aspen Custom Modeler reciprocating engine electrical generator model to investigate the capability of reciprocating engine electrical generation to balance stochastic renewable energy.

  15. Coupling of translational and rotational motion in chiral liquids in electromagnetic and circularly polarised electric fields.

    Science.gov (United States)

    English, Niall J; Kusalik, Peter G; Woods, Sarah A

    2012-03-07

    Non-equilibrium molecular dynamics simulations of R and S enantiomers of 1,1-chlorofluoroethane, both for pure liquids and racemic mixtures, have been performed at 298 K in the absence and presence of both electromagnetic (e/m) and circularly polarised electric (CP) fields of varying frequency (100-2200 GHz) and intensity (0.025-0.2 V Å(-1) (rms)). Significant non-thermal field effects were noted in the coupling of rotational and translational motion; for instance, in microwave and far-infrared (MW/IR) e/m fields, marked increases in rotational and translational diffusion vis-à-vis the zero-field case took place at 0.025-0.1 V Å(-1) (rms), with a reduction in translational diffusion vis-à-vis the zero-field case above 0.1 V Å(-1) (rms) above 100 GHz. This was due to enhanced direct coupling of rotational motion with the more intense e/m field at the ideal intrinsic rotational coupling frequency (approximately 700 GHz) leading to such rapidly oscillating rotational motion that extent of translational motion was effectively reduced. In the case of CP fields, rotational and translational diffusion was also enhanced for all intensities, particularly at approximately 700 GHz. For both MW/IR and CP fields, non-linear field effects were evident above around 0.1 V Å(-1) (rms) intensity, in terms of enhancements in translational and rotational motion. Simulation of 90-10 mol. % liquid mixtures of a Lennard-Jones solvent with R and S enantiomer-solutes in MW/IR and CP fields led to more limited promotion of rotational and translational diffusion, due primarily to increased frictional effects. For both e/m and CP fields, examination of the laboratory- and inertial-frame auto- and cross-correlation functions of velocity and angular velocity demonstrated the development of explicit coupling with the external fields at the applied frequencies, especially so in the more intense fields where nonlinear effects come into play. For racemic mixtures, elements of the laboratory

  16. Automatic mechanical fault assessment of small wind energy systems in microgrids using electric signature analysis

    DEFF Research Database (Denmark)

    Skrimpas, Georgios Alexandros; Marhadi, Kun Saptohartyadi; Jensen, Bogi Bech

    2013-01-01

    A microgrid is a cluster of power generation, consumption and storage systems capable of operating either independently or as part of a macrogrid. The mechanical condition of the power production units, such as the small wind turbines, is considered of crucial importance especially in the case...... of islanded operation. In this paper, the fault assessment is achieved efficiently and consistently via electric signature analysis (ESA). In ESA the fault related frequency components are manifested as sidebands of the existing current and voltage time harmonics. The energy content between the fundamental, 5...

  17. Constructing a Plastic Bottle Wind Turbine as a Practical Aid for Learning about Using Wind Energy to Generate Electricity

    Science.gov (United States)

    Appleyard, S. J.

    2009-01-01

    A simple horizontal axis wind turbine can be easily constructed using a 1.5 l PET plastic bottle, a compact disc and a small dynamo. The turbine operates effectively at low wind speeds and has a rotational speed of 500 rpm at a wind speed of about 14 km h[superscript -1]. The wind turbine can be used to demonstrate the relationship between open…

  18. Electric field in the magnetotail depending on the geomagnetic activity level and intensity Esub(y) in the solar wind

    International Nuclear Information System (INIS)

    Pudovkin, M.I.; Osipov, V.V.; Shukhtina, M.A.; Zajtseva, S.A.; AN SSSR, Vladivostok. Dal'nevostochnyh Nauchnyj Tsentr)

    1982-01-01

    The value of the large-scale electric field in the near magnetotail on AE-index variations delay in relation to interplanetary electric field variations is estimated. It is obtained that the electric field value in a tail increases with magnetic activity level. The solar wind electric field under strong magnetic disturbance penetrates into the magnetosphere practically without weakening and is essentially weakened in magneto-quit conditions. Calculated values of the electric field magnitude in the magnetotail (0.01-1mBm) are in agreement with those obtained earlier [ru

  19. Fluid power network for centralized electricity generation in offshore wind farms

    International Nuclear Information System (INIS)

    Jarquin-Laguna, A

    2014-01-01

    An innovative and completely different wind-energy conversion system is studied where a centralized electricity generation within a wind farm is proposed by means of a hydraulic network. This paper presents the dynamic interaction of two turbines when they are coupled to the same hydraulic network. Due to the stochastic nature of the wind and wake interaction effects between turbines, the operating parameters (i.e. pitch angle, rotor speed) of each turbine are different. Time domain simulations, including the main turbine dynamics and laminar transient flow in pipelines, are used to evaluate the efficiency and rotor speed stability of the hydraulic system. It is shown that a passive control of the rotor speed, as proposed in previous work for a single hydraulic turbine, has strong limitations in terms of performance for more than one turbine coupled to the same hydraulic network. It is concluded that in order to connect several turbines, a passive control strategy of the rotor speed is not sufficient and a hydraulic network with constant pressure is suggested. However, a constant pressure network requires the addition of active control at the hydraulic motors and spear valves, increasing the complexity of the initial concept. Further work needs to be done to incorporate an active control strategy and evaluate the feasibility of the constant pressure hydraulic network

  20. HORIZONTAL AXIS MARINE CURRENT TURBINE DESIGN FOR WIND-ELECTRIC HYBRID SAILING BOAT

    Directory of Open Access Journals (Sweden)

    Serkan Ekinci

    2017-01-01

    Full Text Available In recent decades, the number of theoretical studies and applications on electric power production from renewable sources such as wind, solar, sea and tidal flows, has been increasing rapidly. Marine Current Turbines (MCTs, among the power turbines, produce power from alternating flows and are a means of power production even at lower flow rates in oceans and seas. In this study, while maintaining functional requirements, an initial and detailed design (mechanic and hydrodynamic, of an MCT fixed on a sailing boat and at sail which extracts power from the flow around the boat, is undertaken. In the design stages, for analysis and optimization of the marine turbine blade design, the Momentum Blade Element Method is utilized. The Horizontal Axis Marine Turbine (HAMT, determined by the initial and mechanical design, is illustrated with its components included. Computational fluid dynamics (CFD analyses, covering turbine pod geometry at required flow rates and turbine speeds are performed. These analyses are performed very close to real conditions, considering sailing with and without the turbine running (on and off states. The alternator is determined from the results, and the final design which meets the design requirements, is obtained. As a result, a user friendly and innovative turbine design for sail boats, offering more power and efficiency, which is longer lasting compared to solar and wind technologies, that also makes use of renewable sources, such as wind and/or solar, and in addition stores and uses accumulated energy when needed, is proposed.

  1. Regulation of the wind power production. Contribution of the electric vehicles and other energy storage systems

    Energy Technology Data Exchange (ETDEWEB)

    Mateus, Carlos B. [Instituto de Meteorologia, Lisboa (Portugal); Estanqueiro, Ana [INETI/LNEG - National Laboratory for Energy and Geology, Lisbon (Portugal)

    2012-07-01

    The increase in penetration of variable renewable energy sources (RES) introduced additional difficulties regarding the management of the Portuguese Power System. This is mainly due to the high temporal variability and low controllability, characteristics of these kinds of sources. There is a real need to reduce the impact of non-dispatchable RES sources; maximizing their penetration and minimizing curtailment. This is especially true for wind power and run-of-the-river hydro (ROR); as it appears beneficial to combine their variable production with added capacity of energy storage and demand side management; thereby increasing the flexibility of the power system as a whole. This paper aims to assess the excess wind generation (and other non-dispatchable sources); this for periods of production's excess in a 2020 timeframe, and assuming different weather scenarios. The adjustment of wind power generation (WPG) profile to the load profile is also addressed; the result is computed in the form of the value of the energy temporally deferred, using Pumped Hydro Storage (PHS) power plants as well as electric Vehicles (EVs). (orig.)

  2. Air-Breathing Ramjet Electric Propulsion for Controlling Low-Orbit Spacecraft Motion to Compensate for Aerodynamic Drag

    Science.gov (United States)

    Erofeev, A. I.; Nikiforov, A. P.; Popov, G. A.; Suvorov, M. O.; Syrin, S. A.; Khartov, S. A.

    2017-12-01

    Problems on designing the air-breathing ramjet electric propulsion thruster for controlling loworbit spacecraft motion are examined in the paper. Information for choosing orbits' altitudes for reasonable application of an air-breathing ramjet electric propulsion thruster and propellant exhaust velocity is presented. Estimates of the probable increase of gas concentration in the area of air-breathing ramjet ionization are presented. The test results of the thruster are also given.

  3. The market of new electric energies. Wind, solar, biomass, hydroelectricity: which perspectives by 2015?

    International Nuclear Information System (INIS)

    2012-01-01

    This report highlights the consequences of the modification of the energy economic environment, the main trends of the sector, and predictable evolutions. A first part presents the situation of the French market of new electric energy sources in 2011 and its perspectives by 2015 for hydroelectricity, wind energy, photovoltaic energy, and biomass-based energy (production capacities, installations to be connected, electricity production and its share in electricity consumption), and discusses the main challenges faced by the profession. The second part proposes a comparison between these new energies and nuclear energy in terms of economic structure (number of companies, staff, turnover, public investment, and so on), synthetic sheets of the different renewable sectors, and an overview of the World and European markets of new electric energies. The third part identifies the existing actors. The fourth part analyses growth brakes and drivers (French energy policy, economic context for the 2011-2015 period, other factors which have influence on the market). The fifth part proposes a large set of economic and financial indicators for 200 actors of the sector

  4. Interfacial motion in flexo- and order-electric switching between nematic filled states

    International Nuclear Information System (INIS)

    Blow, M L; Telo da Gama, M M

    2013-01-01

    We consider a nematic liquid crystal, in coexistence with its isotropic phase, in contact with a substrate patterned with rectangular grooves. In such a system the nematic phase may fill the grooves without the occurrence of complete wetting. There may exist multiple (meta)stable filled states, each characterized by the type of distortion (bend or splay) in each corner of the groove and by the shape of the nematic–isotropic interface, and additionally the plateaux that separate the grooves may be either dry or wet with a thin layer of nematic. Using numerical simulations, we analyse the dynamical response of the system to an externally-applied electric field, with the aim of identifying switching transitions between these filled states. We find that order-electric coupling between the fluid and the field provides a means of switching between states where the plateaux between grooves are dry and states where they are wetted by a nematic layer, without affecting the configuration of the nematic within the groove. We find that flexoelectric coupling may change the nematic texture in the groove, provided that the flexoelectric coupling differentiates between the types of distortion at the corners of the substrate. We identify intermediate stages of the transitions, and the role played by the motion of the nematic–isotropic interface. We determine quantitatively the field magnitudes and orientations required to effect each type of transition. (paper)

  5. On the synergy between large electric vehicle fleet and high wind penetration – An analysis of the Danish case

    DEFF Research Database (Denmark)

    Krog Ekman, Claus

    2011-01-01

    Increasing the level of wind power penetration beyond the present level in the Danish power system implies large challenges when it comes to energy management and system stability. Plug-in electric vehicles promise to contribute to the flexibility of the energy system by creating a link between...... the power system and the transportation sector and provide the possibility to make use of the inherent energy storage of a large electric vehicle (EV) fleet. The present work investigates the effects of different EV charging strategies on the balance between wind power production and consumption in a future...... Danish power system. The results show that an electrification of the transport sector will indeed reduce the excess of wind power, but additional mechanisms are needed if the full wind power potential in Denmark is utilized. Further it is foreseen that the vehicle-to-grid option (where the vehicle...

  6. Wind power integration with heat pumps, heat storages, and electric vehicles – Energy systems analysis and modelling

    DEFF Research Database (Denmark)

    Hedegaard, Karsten

    The fluctuating and only partly predictable nature of wind challenges an effective integration of large wind power penetrations. This PhD thesis investigates to which extent heat pumps, heat storages, and electric vehicles can support the integration of wind power. Considering the gaps in existing...... in an energy system context. Energy systems analyses reveal that the heat pumps can even without flexible operation contribute significantly to facilitating larger wind power investments and reducing system costs, fuel consumption, and CO2 emissions. When equipping the heat pumps with heat storages, only...... moderate additional benefits are achieved. Hereof, the main benefit is that the need for investing in peak/reserve capacities can be reduced through peak load shaving. It is more important to ensure flexible operation of electric vehicles than of individual heat pumps, due to differences in the load...

  7. Electricity generation comparison of food waste-based bioenergy with wind and solar powers: A mini review

    Directory of Open Access Journals (Sweden)

    Ngoc Bao Dung Thi

    2016-09-01

    Full Text Available The food waste treatment-based anaerobic digestion has been proven to play a primary role in electricity industry with high potentially economic benefits, which could reduce electricity prices in comparison with other renewable energy resources such as wind and solar power. The levelized costs of electricity were reported to be 65, 190, 130 and 204 US$ MWh−1 for food waste treatment in anaerobic landfill, anaerobic digestion biogas, solar power, and wind power, respectively. As examples, the approaches of food waste treatment via anaerobic digestion to provide a partial energy supply for many countries in future were estimated as 42.9 TWh yr−1 in China (sharing 0.87% of total electricity generation, 7.04 TWh yr−1 in Japan (0.64% of total electricity generation and 13.3 TWh yr−1 in the US (0.31% of total electricity generation. Electricity generation by treating food waste is promised to play an important role in renewable energy management. Comparing with wind and solar powers, converting food waste to bioenergy provides the lowest investment costs (500 US$ kW−1 and low operation cost (0.1 US$ kWh−1. With some limits in geography and season of other renewable powers, using food waste for electricity generation is supposedly to be a suitable solution for balancing energy demand in many countries.

  8. Optimal bidding in Turkey day ahead electricity market for wind energy and pumped storage hydro power plant

    OpenAIRE

    Ceyhun Yıldız; Mustafa Şekkeli

    2016-01-01

    In electrical grid; when the demand power increases energy prices increase, when the demand decreases energy prices decrease. For this reason; to increase the total daily income, it is required to shift generations to the hours that high demand power values occurred. Wind Power Plants (WPP) have unstable and uncontrollable generation characteristic. For this reason, energy storage systems are needed to shift the generations of WPPs in time scale. In this study, four wind power plants (WPP) wh...

  9. EVIDENCE FOR QUASI-ADIABATIC MOTION OF CHARGED PARTICLES IN STRONG CURRENT SHEETS IN THE SOLAR WIND

    Energy Technology Data Exchange (ETDEWEB)

    Malova, H. V. [Scobeltsyn Nuclear Physics Institute of Lomonosov Moscow State University, Moscow (Russian Federation); Popov, V. Yu.; Grigorenko, E. E.; Petrukovich, A. A.; Zelenyi, L. M. [Space Research Institute of the Russian Academy of Sciences, Moscow (Russian Federation); Delcourt, D. [Laboratoire de Physique des Plasmas, Ecole Politechnique, CNRS (France); Sharma, A. S. [Department of Astronomy, University of Maryland, College Park, MD (United States); Khabarova, O. V. [Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of the Russian Academy of Sciences (IZMIRAN), Moscow (Russian Federation)

    2017-01-01

    We investigate quasi-adiabatic dynamics of charged particles in strong current sheets (SCSs) in the solar wind, including the heliospheric current sheet (HCS), both theoretically and observationally. A self-consistent hybrid model of an SCS is developed in which ion dynamics is described at the quasi-adiabatic approximation, while the electrons are assumed to be magnetized, and their motion is described in the guiding center approximation. The model shows that the SCS profile is determined by the relative contribution of two currents: (i) the current supported by demagnetized protons that move along open quasi-adiabatic orbits, and (ii) the electron drift current. The simplest modeled SCS is found to be a multi-layered structure that consists of a thin current sheet embedded into a much thicker analog of a plasma sheet. This result is in good agreement with observations of SCSs at ∼1 au. The analysis of fine structure of different SCSs, including the HCS, shows that an SCS represents a narrow current layer (with a thickness of ∼10{sup 4} km) embedded into a wider region of about 10{sup 5} km, independently of the SCS origin. Therefore, multi-scale structuring is very likely an intrinsic feature of SCSs in the solar wind.

  10. Mobile art pattern wind-force of generation of electricity of prod; Purodo no mobairu atogata furyoku hatsuden

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Yoriyasu

    1999-03-01

    How to think about usual force of the wind generation of electricity is the generation of electricity facilities where a propeller type is large-scale by the efficiency emphasis. However, as a scale grows bigger, it is understood more that it isn`t necessarily good if usual facilities are popularized when badness of the operating rate that it passes through the noise pollution and the year such as the velocity of the wind 4-5m/s of cut in and so on is taken into consideration. Even if the same force of the wind generation of electricity is said, it does from the beginning of the idea of cooperative plod, and a concept is wrong, and it is the story which must not be compared with a large force of the wind generator. The various functional beauty when that molding fruit stopped to become `the sculpture that wind can be seen` rather rotates is more important in the way of thinking about efficiency priority than to say an abstract expression such as `the love` which can`t have an idea, and `kindness` as sculpture to move by the wind when it says. (NEDO)

  11. Decision support for the definition of wind turbine systems adequacy to site specificities and weak electrical networks

    International Nuclear Information System (INIS)

    Arbaoui, A.

    2006-10-01

    A decision support system for the definition of wind turbine systems is developed by taking into account the wind and site characteristics, the wind turbine components and the electrical network properties close to the site. The approach is based on functional analysis, on the investigation of the functional fluxes and on the definition of a model suitable for supporting decision at the preliminary stages of wind turbine design. The complete set of solutions derived from the model is determined using a Constraint Satisfaction Problem solver. The intrinsic capability of the model to support decision is derived from the investigation of the model parsimony, precision, exactness and specialization. The model takes into account performance criteria resulting from knowledge of manufacturers, distributors and investors. These criteria are used to discriminate design alternatives. Design alternatives correspond to choices of site (wind, electric network) and wind turbine architectures (related to 7 design variables). Performance criteria are the cost of electric kWh, the amount of energy being produced and the discounted total cost of the project. Electric network connection to wind turbines is taken into account through slow variations of the voltage and Flickers phenomenon. First, the maximal rate of penetration of the wind turbine energy production is determined. Next, two design alternatives have been investigated to improve wind turbine system integration in electric distribution networks. These alternatives are a reactive power control system and an inertial energy storage system. Inertial storage systems seem to be more expensive than reactive power control systems for this type of application. The influence of site specificities on decision making process has been established through three different sites (a Mediterranean site and two sites located in northern Europe). Profits relative to the cost of kWh appear to be high for Mediterranean sites. Most of the

  12. Minimization of Motion Smear: Reducing Avian Collision with Wind Turbines; Period of Performance: July 12, 1999 -- August 31, 2002

    Energy Technology Data Exchange (ETDEWEB)

    Hodos, W.

    2003-08-01

    Collisions with wind turbines can be a problem for many species of birds. Of particular concern are collisions by eagles and other protected species. This research study used the laboratory methods of physiological optics, animal psychophysics, and retinal electrophysiology to analyze the causes of collisions and to evaluate visual deterrents based on the results of this analysis. Bird collisions with the seemingly slow-moving turbines seem paradoxical given the superb vision that most birds, especially raptors, possess. However, our optical analysis indicated that as the eye approaches the rotating blades, the retinal image of the blade (which is the information that is transmitted to the animal's brain) increases in velocity until it is moving so fast that the retina cannot keep up with it. At this point, the retinal image becomes a transparent blur that the bird probably interprets as a safe area to fly through, with disastrous consequences. This phenomenon is called"motion smear" or"motion blur."

  13. Multi-Temporal Decomposed Wind and Load Power Models for Electric Energy Systems

    Science.gov (United States)

    Abdel-Karim, Noha

    This thesis is motivated by the recognition that sources of uncertainties in electric power systems are multifold and may have potentially far-reaching effects. In the past, only system load forecast was considered to be the main challenge. More recently, however, the uncertain price of electricity and hard-to-predict power produced by renewable resources, such as wind and solar, are making the operating and planning environment much more challenging. The near-real-time power imbalances are compensated by means of frequency regulation and generally require fast-responding costly resources. Because of this, a more accurate forecast and look-ahead scheduling would result in a reduced need for expensive power balancing. Similarly, long-term planning and seasonal maintenance need to take into account long-term demand forecast as well as how the short-term generation scheduling is done. The better the demand forecast, the more efficient planning will be as well. Moreover, computer algorithms for scheduling and planning are essential in helping the system operators decide what to schedule and planners what to build. This is needed given the overall complexity created by different abilities to adjust the power output of generation technologies, demand uncertainties and by the network delivery constraints. Given the growing presence of major uncertainties, it is likely that the main control applications will use more probabilistic approaches. Today's predominantly deterministic methods will be replaced by methods which account for key uncertainties as decisions are made. It is well-understood that although demand and wind power cannot be predicted at very high accuracy, taking into consideration predictions and scheduling in a look-ahead way over several time horizons generally results in more efficient and reliable utilization, than when decisions are made assuming deterministic, often worst-case scenarios. This change is in approach is going to ultimately require new

  14. The Use of Design Models of Wind-Electric Set with a Horizontal Axis of Rotation of the Wind Wheel for Dynamic Calculations at Urban Development

    Directory of Open Access Journals (Sweden)

    Konstantinov Igor

    2016-01-01

    Full Text Available The issues of modern urban development raise a significant question about an environmental cleanliness of progressing cities. Energy sources which are running on fuel cause tremendous harm to the atmosphere. Therefore, special attention is paid to the rational use of natural renewable resources such as wind and solar energy. Wind-electric sets, or wind turbines, are able to work autonomously, which is also important for the development of modern “smart” cities. Currently, the most commonly used design of wind turbines is the system which has the form of a tower of circular cross section (also called pipe, which carries at the upper end a nacelle with wind wheel. When such a system is being designed in urban conditions the wind pulsation and seismic calculations are added to the standard calculations. These added calculations are dynamic loads. It is known that in the process of solution of dynamic tasks design models of various levels of approximation can be used. It occurs due to stages of the design and other factors. The question of errors, which are associated with the use of a dissected, or partitioned, design scheme, raises.

  15. Using Electric Vehicles to Meet Balancing Requirements Associated with Wind Power

    Energy Technology Data Exchange (ETDEWEB)

    Tuffner, Francis K.; Kintner-Meyer, Michael CW

    2011-07-31

    Many states are deploying renewable generation sources at a significant rate to meet renewable portfolio standards. As part of this drive to meet renewable generation levels, significant additions of wind generation are planned. Due to the highly variable nature of wind generation, significant energy imbalances on the power system can be created and need to be handled. This report examines the impact on the Northwest Power Pool (NWPP) region for a 2019 expected wind scenario. One method for mitigating these imbalances is to utilize plug-in hybrid electric vehicles (PHEVs) or battery electric vehicles (BEVs) as assets to the grid. PHEVs and BEVs have the potential to meet this demand through both charging and discharging strategies. This report explores the usage of two different charging schemes: V2GHalf and V2GFull. In V2GHalf, PHEV/BEV charging is varied to absorb the additional imbalance from the wind generation, but never feeds power back into the grid. This scenario is highly desirable to automotive manufacturers, who harbor great concerns about battery warranty if vehicle-to-grid discharging is allowed. The second strategy, V2GFull, varies not only the charging of the vehicle battery, but also can vary the discharging of the battery back into the power grid. This scenario is currently less desirable to automotive manufacturers, but provides an additional resource benefit to PHEV/BEVs in meeting the additional imbalance imposed by wind. Key findings in the report relate to the PHEV/BEV population required to meet the additional imbalance when comparing V2GHalf to V2GFull populations, and when comparing home-only-charging and work-and-home-charging scenarios. Utilizing V2GFull strategies over V2GHalf resulted in a nearly 33% reduction in the number of vehicles required. This reduction indicates fewer vehicles are needed to meet the unhandled energy, but they would utilize discharging of the vehicle battery into the grid. This practice currently results in the

  16. Comparative Study of Electric Energy Storages and Thermal Energy Auxiliaries for Improving Wind Power Integration in the Cogeneration System

    Directory of Open Access Journals (Sweden)

    Yanjuan Yu

    2018-01-01

    Full Text Available In regards to the cogeneration system in Northern China, mainly supported by combined heat and power (CHP plants, it usually offers limited operation flexibility due to the joint production of electric and thermal power. For that large-scale wind farms included in the cogeneration system, a large amount of wind energy may have to be wasted. To solve this issue, the utilization of the electric energy storages and the thermal energy auxiliaries are recommended, including pumped hydro storage (PHS, compressed air energy storage (CAES, hydrogen-based energy storage (HES, heat storage (HS, electric boilers (EB, and heat pumps (HP. This paper proposes a general evaluation method to compare the performance of these six different approaches for promoting wind power integration. In consideration of saving coal consumption, reducing CO2 emissions, and increasing investment cost, the comprehensive benefit is defined as the evaluation index. Specifically, a wind-thermal conflicting expression (WTCE is put forward to simplify the formulation of the comprehensive benefit. Further, according to the cogeneration system of the West Inner Mongolia (WIM power grid, a test system is modelled to perform the comparison of the six different approaches. The results show that introducing the electric energy storages and the thermal energy auxiliaries can both contribute to facilitating wind power integration, and the HP can provide the best comprehensive benefit.

  17. Wind-generated Electricity in China: Decreasing Potential, Inter-annual Variability and Association with Changing Climate.

    Science.gov (United States)

    Sherman, Peter; Chen, Xinyu; McElroy, Michael B

    2017-11-24

    China hosts the world's largest market for wind-generated electricity. The financial return and carbon reduction benefits from wind power are sensitive to changing wind resources. Wind data derived from an assimilated meteorological database are used here to estimate what the wind generated electricity in China would have been on an hourly basis over the period 1979 to 2015 at a geographical resolution of approximately 50 km × 50 km. The analysis indicates a secular decrease in generating potential over this interval, with the largest declines observed for western Inner Mongolia (15 ± 7%) and the northern part of Gansu (17 ± 8%), two leading wind investment areas. The decrease is associated with long-term warming in the vicinity of the Siberian High (SH), correlated also with the observed secular increase in global average surface temperatures. The long-term trend is modulated by variability relating to the Pacific Decadal Oscillation (PDO) and the Arctic Oscillation (AO). A linear regression model incorporating indices for the PDO and AO, as well as the declining trend, can account for the interannual variability of wind power, suggesting that advances in long-term forecasting could be exploited to markedly improve management of future energy systems.

  18. Aeroelastic impact of above-rated wave-induced structural motions on the near-wake stability of a floating offshore wind turbine rotor

    Science.gov (United States)

    Rodriguez, Steven; Jaworski, Justin

    2017-11-01

    The impact of above-rated wave-induced motions on the stability of floating offshore wind turbine near-wakes is studied numerically. The rotor near-wake is generated using a lifting-line free vortex wake method, which is strongly coupled to a finite element solver for kinematically nonlinear blade deformations. A synthetic time series of relatively high-amplitude/high-frequency representative of above-rated conditions of the NREL 5MW referece wind turbine is imposed on the rotor structure. To evaluate the impact of these above-rated conditions, a linear stability analysis is first performed on the near wake generated by a fixed-tower wind turbine configuration at above-rated inflow conditions. The platform motion is then introduced via synthetic time series, and a stability analysis is performed on the wake generated by the floating offshore wind turbine at the same above-rated inflow conditions. The stability trends (disturbance modes versus the divergence rate of vortex structures) of the two analyses are compared to identify the impact that above-rated wave-induced structural motions have on the stability of the floating offshore wind turbine wake.

  19. Tracking of macroscopic particle motions generated by a turbulent wind via digital image analysis

    Science.gov (United States)

    Ciccone, A. D.; Kawall, J. G.; Keffer, J. F.

    A novel technique utilizing the basic principles of two-dimensional signal analysis and artificial intelligence/computer vision to reconstruct the Lagrangian particle trajectories from flow visualization images of macroparticle motions in a turbulent boundary layer is presented. Since, in most cases, the entire trajectory of a particle could not be viewed in one photographic frame (the particles were moving at a high velocity over a small field of view), a stochastic model was developed to complete the trajectories and obtain statistical data on particle velocities. The associated programs were implemented on a Cray supercomputer to optimize computational costs and time.

  20. Feasibility study on economic operation of wind farms in the electric power system of the Republic of Croatia

    International Nuclear Information System (INIS)

    Rabadan, L.P.; Sansevic, M.; Klarin, B.

    1996-01-01

    In this work are analyzed island and coastal locations on the Adriatic Sea as possible sites of wind farms. The analysis is based on the expert system developed by authors of other literature. The macrolocation selection is performed by the multicriterial decision-making method and in compliance with the current world approach to their wind potential and some other criteria. The choice of wind turbine generator (WTG) unit is based on the fundamental criteria: operational efficiency on the given location, price per installed kW, and price of the generated electricity. The results obtained in this study show that the contribution in electricity yield from the selected wind power plants could amount to 4.33% of the electricity generated by the Croatian power plants in the year 1990. The calculations of electricity costs are based on the quantity of electricity obtained by simulating the operation of the best WTG units selected from the ES database and including other influential factors. In the choice of macrolocations and WTG units the fuzzy method is implemented as part of the ES. (author)

  1. Feasibility study on economic operation of wind farms in the electric power system of the Republic of Croatia

    Energy Technology Data Exchange (ETDEWEB)

    Rabadan, L.P.; Sansevic, M.; Klarin, B. [Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, Split (Croatia)

    1996-12-31

    In this work are analyzed island and coastal locations on the Adriatic Sea as possible sites of wind farms. The analysis is based on the expert system developed by authors of other literature. The macrolocation selection is performed by the multicriterial decision-making method and in compliance with the current world approach to their wind potential and some other criteria. The choice of wind turbine generator (WTG) unit is based on the fundamental criteria: operational efficiency on the given location, price per installed kW, and price of the generated electricity. The results obtained in this study show that the contribution in electricity yield from the selected wind power plants could amount to 4.33% of the electricity generated by the Croatian power plants in the year 1990. The calculations of electricity costs are based on the quantity of electricity obtained by simulating the operation of the best WTG units selected from the ES database and including other influential factors. In the choice of macrolocations and WTG units the fuzzy method is implemented as part of the ES. (author)

  2. Visualization of the elastic blade motion of an operating wind turbine

    Energy Technology Data Exchange (ETDEWEB)

    Ronsten, Goeran

    2005-04-01

    Blade elastic displacement were successfully tracked by means of digital photographic recording using both Light Emitting Diods; LEDs, and reflexes mounted on a wind turbine blade. A procedure for image analysis was developed. The output from the image analysis was co-ordinates of the objects under investigation. Although the method developed is useful in producing results it still remains to verify the integrity of the results versus, for example, load measurements. The image analysis carried out and presented in this report shows that verification of simulation of blade movements is attainable. However, exact outdoor inflow conditions are extremely difficult to measure and it is therefore not possible to emulate every situation in detail. An increased knowledge of actual blade translation and rotation will nevertheless enable improvement of structural dynamics simulation codes. This is an insight which will grow with the size of future turbines.

  3. Prospects for generating electricity by large onshore and offshore wind farms

    DEFF Research Database (Denmark)

    Volker, Patrick; Hahmann, Andrea N.; Badger, Jake

    2017-01-01

    The decarbonisation of energy sources requires additional investments in renewable technologies, including the installation of onshore and offshore wind farms. For wind energy to remain competitive, wind farms must continue to provide low-cost power even when covering larger areas. Inside very...... on the local free-stream wind speed, the surface characteristics, and the turbine density. In onshore regions with moderate winds the power density of very large wind farms reaches 1 W m−2, whereas in offshore regions with very strong winds it exceeds 3 W m−2. Despite a relatively low power density, onshore...... regions with moderate winds offer potential locations for very large wind farms. In offshore regions, clusters of smaller wind farms are generally preferable; under very strong winds also very large offshore wind farms become efficient....

  4. Wind power systems for individual applications. [electric power supplies for homes

    Science.gov (United States)

    Clews, H. M.

    1973-01-01

    A small windpower system is described which is suitable for electrifying a house. The self-contained unit consists of a two kilowatt wind driven generator, a set of 19 storage batteries, a small dc to ac inverter, and a gasoline generator for use as an emergency backup system in case of prolonged calm periods. Cost effectiveness of the electricity generated by this windmill system comes out to about 15 cents per kilowatt hour - assuming a 10 year life for the batteries and a 20 year life for the other components. Some other small windpower systems are also described, and it is shown that a windpowered generator in the 15- to 25-kilowatt output range coupled to a direct heated water storage system is able to heat a typical New England home.

  5. Effect of Dimension and Shape of Magnet on the Performance AC Generator with Translation Motion

    Science.gov (United States)

    Indriani, A.; Dimas, S.; Hendra

    2018-02-01

    The development of power plants using the renewable energy sources is very rapid. Renewable energy sources used solar energy, wind energy, ocean wave energy and other energy. All of these renewable energy sources require a processing device or a change of motion system to become electrical energy. One processing device is a generator which have work principle of converting motion (mechanical) energy into electrical energy with rotary shaft, blade and other motion components. Generator consists of several types of rotation motion and linear motion (translational). The generator have components such as rotor, stator and anchor. In the rotor and stator having magnet and winding coil as an electric generating part of the electric motion force. Working principle of AC generator with linear motion (translation) also apply the principle of Faraday that is using magnetic induction which change iron magnet to produce magnetic flux. Magnetic flux is captured by the stator to be converted into electrical energy. Linear motion generators consist of linear induction machine, wound synchronous machine field, and permanent magnet synchronous [1]. Performance of synchronous generator of translation motion is influenced by magnet type, magnetic shape, coil winding, magnetic and coil spacing and others. In this paper focus on the neodymium magnet with varying shapes, number of coil windings and gap of magnetic distances. This generator work by using pneumatic mechanism (PLTGL) for power plants system. Result testing of performance AC generator translation motion obtained that maximum voltage, current and power are 63 Volt for diameter winding coil 0.15 mm, number of winding coil 13000 and distance of magnet 20 mm. For effect shape of magnet, maximum voltage happen on rectangle magnet 30x20x5 mm with 4.64 Volt. Voltage and power on effect of diameter winding coil is 14.63 V and 17.82 W at the diameter winding coil 0.7 and number of winding coil is 1260 with the distance of magnet 25

  6. Electrical Energy Forecasting and Optimal Allocation of ESS in a Hybrid Wind-Diesel Power System

    Directory of Open Access Journals (Sweden)

    Hai Lan

    2017-02-01

    Full Text Available Due to the increasingly serious energy crisis and environmental pollution problem, traditional fossil energy is gradually being replaced by renewable energy in recent years. However, the introduction of renewable energy into power systems will lead to large voltage fluctuations and high capital costs. To solve these problems, an energy storage system (ESS is employed into a power system to reduce total costs and greenhouse gas emissions. Hence, this paper proposes a two-stage method based on a back-propagation neural network (BPNN and hybrid multi-objective particle swarm optimization (HMOPSO to determine the optimal placements and sizes of ESSs in a transmission system. Owing to the uncertainties of renewable energy, a BPNN is utilized to forecast the outputs of the wind power and load demand based on historic data in the city of Madison, USA. Furthermore, power-voltage (P-V sensitivity analysis is conducted in this paper to improve the converge speed of the proposed algorithm, and continuous wind distribution is discretized by a three-point estimation method. The Institute of Electrical and Electronic Engineers (IEEE 30-bus system is adopted to perform case studies. The simulation results of each case clearly demonstrate the necessity for optimal storage allocation and the efficiency of the proposed method.

  7. A Biological Micro Actuator: Graded and Closed-Loop Control of Insect Leg Motion by Electrical Stimulation of Muscles

    Science.gov (United States)

    Cao, Feng; Zhang, Chao; Vo Doan, Tat Thang; Li, Yao; Sangi, Daniyal Haider; Koh, Jie Sheng; Huynh, Ngoc Anh; Aziz, Mohamed Fareez Bin; Choo, Hao Yu; Ikeda, Kazuo; Abbeel, Pieter; Maharbiz, Michel M.; Sato, Hirotaka

    2014-01-01

    In this study, a biological microactuator was demonstrated by closed-loop motion control of the front leg of an insect (Mecynorrhina torquata, beetle) via electrical stimulation of the leg muscles. The three antagonistic pairs of muscle groups in the front leg enabled the actuator to have three degrees of freedom: protraction/retraction, levation/depression, and extension/flexion. We observed that the threshold amplitude (voltage) required to elicit leg motions was approximately 1.0 V; thus, we fixed the stimulation amplitude at 1.5 V to ensure a muscle response. The leg motions were finely graded by alternation of the stimulation frequencies: higher stimulation frequencies elicited larger leg angular displacement. A closed-loop control system was then developed, where the stimulation frequency was the manipulated variable for leg-muscle stimulation (output from the final control element to the leg muscle) and the angular displacement of the leg motion was the system response. This closed-loop control system, with an optimized proportional gain and update time, regulated the leg to set at predetermined angular positions. The average electrical stimulation power consumption per muscle group was 148 µW. These findings related to and demonstrations of the leg motion control offer promise for the future development of a reliable, low-power, biological legged machine (i.e., an insect–machine hybrid legged robot). PMID:25140875

  8. A biological micro actuator: graded and closed-loop control of insect leg motion by electrical stimulation of muscles.

    Directory of Open Access Journals (Sweden)

    Feng Cao

    Full Text Available In this study, a biological microactuator was demonstrated by closed-loop motion control of the front leg of an insect (Mecynorrhina torquata, beetle via electrical stimulation of the leg muscles. The three antagonistic pairs of muscle groups in the front leg enabled the actuator to have three degrees of freedom: protraction/retraction, levation/depression, and extension/flexion. We observed that the threshold amplitude (voltage required to elicit leg motions was approximately 1.0 V; thus, we fixed the stimulation amplitude at 1.5 V to ensure a muscle response. The leg motions were finely graded by alternation of the stimulation frequencies: higher stimulation frequencies elicited larger leg angular displacement. A closed-loop control system was then developed, where the stimulation frequency was the manipulated variable for leg-muscle stimulation (output from the final control element to the leg muscle and the angular displacement of the leg motion was the system response. This closed-loop control system, with an optimized proportional gain and update time, regulated the leg to set at predetermined angular positions. The average electrical stimulation power consumption per muscle group was 148 µW. These findings related to and demonstrations of the leg motion control offer promise for the future development of a reliable, low-power, biological legged machine (i.e., an insect-machine hybrid legged robot.

  9. Treatment Wetland Aeration without Electricity? Lessons Learned from the First Experiment Using a Wind-Driven Air Pump

    Directory of Open Access Journals (Sweden)

    Johannes Boog

    2016-11-01

    Full Text Available Aerated treatment wetlands have become an increasingly recognized technology for treating wastewaters from domestic and various industrial origins. To date, treatment wetland aeration is provided by air pumps which require access to the energy grid. The requirement for electricity increases the ecological footprint of an aerated wetland and limits the application of this technology to areas with centralized electrical infrastructure. Wind power offers another possibility as a driver for wetland aeration, but its use for this purpose has not yet been investigated. This paper reports the first experimental trial using a simple wind-driven air pump to replace the conventional electric air blowers of an aerated horizontal subsurface flow wetland. The wind-driven air pump was connected to a two-year old horizontal flow aerated wetland which had been in continuous (24 h aeration since startup. The wind-driven aeration system functioned, however it was not specifically adapted to wetland aeration. As a result, treatment performance decreased compared to prior continuous aeration. Inconsistent wind speed at the site may have resulted in insufficient pressure within the aeration manifold, resulting in insufficient air supply to the wetland. This paper discusses the lessons learned during the experiment.

  10. Techno-economic feasibility of hybrid diesel/PV/wind/battery electricity generation systems for non-residential large electricity consumers under southern Iran climate conditions

    International Nuclear Information System (INIS)

    Baneshi, Mehdi; Hadianfard, Farhad

    2016-01-01

    Highlights: • A hybrid electricity generation system for a large electricity consumer was studied. • The PV and wind electricity potentials under given climate conditions were evaluated. • Technical, economical, and environmental issues of different systems were discussed. • The optimum configuration of components was obtained. • The impacts of governmental incentives on economic viability of systems were examined. - Abstract: This paper aims to study the techno-economical parameters of a hybrid diesel/PV/wind/battery power generation system for a non-residential large electricity consumer in the south of Iran. As a case study, the feasibility of running a hybrid system to meet a non-residential community’s load demand of 9911 kWh daily average and 725 kW peak load demand was investigated. HOMER Pro software was used to model the operation of the system and to identify the appropriate configuration of it based on comparative technical, economical, and environmental analysis. Both stand alone and grid connected systems were modeled. The impacts of annual load growth and governmental energy policies such as providing low interest loan to renewable energy projects, carbon tax, and modifying the grid electricity price on viability of the system were discussed. Results show that for off-grid systems the cost of electricity (COE) and the renewable fraction of 9.3–12.6 ₵/kWh and 0–43.9%, respectively, are achieved with photovoltaic (PV) panel, wind turbine, and battery sizes of 0–1000 kW, 0–600 kW, and 1300 kWh, respectively. For on grid systems without battery storage the range of COE and renewable fraction are 5.7–8.4 ₵/kWh and 0–53%, respectively, for the same sizes of PV panel and wind turbine.

  11. Non-radial solar wind flows induced by the motion of interplanetary coronal mass ejections

    Directory of Open Access Journals (Sweden)

    M. Owens

    2004-12-01

    Full Text Available A survey of the non-radial flows (NRFs during nearly five years of interplanetary observations revealed the average non-radial speed of the solar wind flows to be ~30km/s, with approximately one-half of the large (>100km/s NRFs associated with ICMEs. Conversely, the average non-radial flow speed upstream of all ICMEs is ~100km/s, with just over one-third preceded by large NRFs. These upstream flow deflections are analysed in the context of the large-scale structure of the driving ICME. We chose 5 magnetic clouds with relatively uncomplicated upstream flow deflections. Using variance analysis it was possible to infer the local axis orientation, and to qualitatively estimate the point of interception of the spacecraft with the ICME. For all 5 events the observed upstream flows were in agreement with the point of interception predicted by variance analysis. Thus we conclude that the upstream flow deflections in these events are in accord with the current concept of the large-scale structure of an ICME: a curved axial loop connected to the Sun, bounded by a curved (though not necessarily circular cross section.

    Key words. Interplanetary physics (flare and stream dynamics; interplanetary magnetic fields; interplanetary shocks

  12. Wind blows where (and when) it wants: an analysis of the French electricity production, September-December 2010 - preliminary analysis

    International Nuclear Information System (INIS)

    2011-01-01

    This document analyses the set of data published on the RTE web site and concerning the electricity production and consumption in France from September to December 2010. Having a closer look to the wind energy production, it notably shows that, as expected, all steerable means of production play a coordinated role in covering the required power needs. The analysis of the wind energy power shows a 23 pc average efficiency which is associated to the strong fluctuations which are typical for this type of intermittent production. It notices that time and energy distributions of wind energy power supplied to the network are not related to increased electricity needs during this autumn period which is marked by several cold waves

  13. Optimization of Electric Power Systems for Off-Grid Domestic Applications: An Argument for Wind/Photovoltaic Hybrids

    Energy Technology Data Exchange (ETDEWEB)

    Jennings, W.; Green, J.

    2001-01-01

    The purpose of this research was to determine the optimal configuration of home power systems relevant to different regions in the United States. The hypothesis was that, regardless of region, the optimal system would be a hybrid incorporating wind technology, versus a photovoltaic hybrid system without the use of wind technology. The method used in this research was HOMER, the Hybrid Optimization Model for Electric Renewables. HOMER is a computer program that optimizes electrical configurations under user-defined circumstances. According to HOMER, the optimal system for the four regions studied (Kansas, Massachusetts, Oregon, and Arizona) was a hybrid incorporating wind technology. The cost differences between these regions, however, were dependent upon regional renewable resources. Future studies will be necessary, as it is difficult to estimate meteorological impacts for other regions.

  14. Off-grid hybrid electric power supply system, using a combination of solar cells, small scale wind turbine and batteries

    Energy Technology Data Exchange (ETDEWEB)

    Schroeter, W.

    1994-03-01

    The design of an off-grid electric power supply system consisting of a small scale wind turbine, a combination of solar cells and batteries is described. The robust, small scale FC 4000 wind turbine, which needs little maintenance, can be used under varying climatic conditions. It is equipped with a permanent-magnet generator with an output of 1.5 kW. The generator`s rotor is directly coupled with the wind turbine`s rotor and is without a gearbox, so the frequency and output varies according to wind speed. The 12 m{sup 2} solar cell system consists of round modules embedded in glass and with an efficiency of 13%. The lead acid batteries are used when power consumption exceeds production and store energy for future use. Further adjustments are necessary in order to optimize the performance of this hybrid system. (AB)

  15. Inexact stochastic risk-aversion optimal day-ahead dispatch model for electricity system management with wind power under uncertainty

    International Nuclear Information System (INIS)

    Ji, Ling; Huang, Guo-He; Huang, Lu-Cheng; Xie, Yu-Lei; Niu, Dong-Xiao

    2016-01-01

    High penetration of wind power generation and deregulated electricity market brings a great challenge to the electricity system operators. It is crucial to make optimal strategy among various generation units and spinning reserve for supporting the system safety operation. By integrating interval two-stage programming and stochastic robust programming, this paper proposes a novel robust model for day-ahead dispatch and risk-aversion management under uncertainties. In the proposed model, the uncertainties are expressed as interval values with different scenario probability. The proposed method requires low computation, and still retains the complete information. A case study is to validate the effectiveness of this approach. Facing the uncertainties of future demand and electricity price, the system operators need to make optimal dispatch strategy for thermal power units and wind turbine, and arrange proper spinning reserve and flexible demand response program to mitigate wind power forecasting error. The optimal strategies provide the system operators with better trade-off between the maximum benefits and the minimum system risk. In additional, two different market rules are compared. The results show that extra financial penalty for the wind power dispatch deviation is another efficient way to enhance the risk consciousness of decision makers and lead to more conservative strategy. - Highlights: • An inexact two-stage stochastic robust programming model for electricity system with wind power penetration. • Uncertainties expressed as discrete intervals and probability distributions. • Demand response program was introduced to adjust the deviation in real-time market. • Financial penalty for imbalance risk from wind power generation was evaluated.

  16. Characterization of the High-Speed-Stage Bearing Skidding of Wind Turbine Gearboxes Induced by Dynamic Electricity Grid Events: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Helsen, Jan; Guillaume, Patrick; Guo, Yi; Keller, Jonathan

    2016-05-18

    Bearing behavior is an important factor for wind turbine drivetrain reliability. Extreme loads and dynamic excitations pose challenges to the bearing design and therefore its performance. Excessive skidding of the bearing rollers should be avoided because it can cause scuffing failures. Excitations coming from wind and the electricity grid can subject the drivetrain to fluctuating torque and nontorque loads. Wind-induced excitations have been investigated predominantly in literature. However, modern wind turbines are subjected more and more to grid-induced loads because of stricter electricity grid regulations. For example, during fault-ride-through events, turbines are required to stay connected for a longer period of time during the grid failure. This work investigates the influence of electrically induced excitations on the skidding behaviour of the tapered roller bearings on the high-speed stage of a wind turbine gearbox. This skidding behaviour during dynamic events is described as a potential bearing failure initiator by many researchers; however, only limited full-scale dynamic testing is documented. Therefore, a dedicated gridloss-type event is defined in the paper and conducted in a dynamometer test on a full-scale wind turbine nacelle. During the event, a complete electricity grid failure is simulated while the turbine is at rated speed and predefined torque levels. Particular focus is on the characterization of the high-speed shaft tapered roller bearing slip behavior. Strain-gauge bridges in grooves along the circumference of the outer ring are used to characterize the bearing load zone in detail. It is shown that during the torque reversals of the transient event, roller slip can be induced. This indicates the potential of the applied load case to go beyond the preload of the tapered roller bearing. Furthermore, the relation between the applied torque and skidding level is studied.

  17. Characterization of the High-Speed-Stage Bearing Skidding of Wind Turbine Gearboxes Induced by Dynamic Electricity Grid Events

    Energy Technology Data Exchange (ETDEWEB)

    Helsen, Jan; Guillaume, Patrick; Guo, Yi; Keller, Jonathan

    2016-07-01

    Bearing behavior is an important factor for wind turbine drivetrain reliability. Extreme loads and dynamic excitations pose challenges to the bearing design and therefore its performance. Excessive skidding of the bearing rollers should be avoided because it can cause scuffing failures. Excitations coming from wind and the electricity grid can subject the drivetrain to fluctuating torque and nontorque loads. Wind-induced excitations have been investigated predominantly in literature. However, modern wind turbines are subjected more and more to grid-induced loads because of stricter electricity grid regulations. For example, during fault-ride-through events, turbines are required to stay connected for a longer period of time during the grid failure. This work investigates the influence of electrically induced excitations on the skidding behaviour of the tapered roller bearings on the high-speed stage of a wind turbine gearbox. This skidding behaviour during dynamic events is described as a potential bearing failure initiator by many researchers; however, only limited full-scale dynamic testing is documented. Therefore, a dedicated gridloss-type event is defined in the paper and conducted in a dynamometer test on a full-scale wind turbine nacelle. During the event, a complete electricity grid failure is simulated while the turbine is at rated speed and predefined torque levels. Particular focus is on the characterization of the high-speed shaft tapered roller bearing slip behavior. Strain-gauge bridges in grooves along the circumference of the outer ring are used to characterize the bearing load zone in detail. It is shown that during the torque reversals of the transient event, roller slip can be induced. This indicates the potential of the applied load case to go beyond the preload of the tapered roller bearing. Furthermore, the relation between the applied torque and skidding level is studied.

  18. A study of wind energy potential: remedy for fluctuation of electric ...

    African Journals Online (AJOL)

    The result is good enough, since the minimum wind speed required to turn the turbine of a wind machine is 3.0ms-1. Comparative analysis using the Wind Speed Scale at 10m heights shows that this value of wind speed can be categorized as moderate especially when compared with other towns in Nigeria. This implies ...

  19. Large-scale integration of optimal combinations of PV, wind and wave power into the electricity supply

    DEFF Research Database (Denmark)

    Lund, Henrik

    2006-01-01

    ancillary services are needed in order to secure the electricity supply system. The idea is to benefit from the different patterns in the fluctuations of different renewable sources. And the purpose is to identify optimal mixtures from a technical point of view. The optimal mixture seems to be when onshore...... wind power produces approximately 50% of the total electricity production from RES. Meanwhile, the mixture between PV and wave power seems to depend on the total amount of electricity production from RES. When the total RES input is below 20% of demand, PV should cover 40% and wave power only 10%. When...

  20. Dynamic modeling and simulation of wind turbines

    International Nuclear Information System (INIS)

    Ghafari Seadat, M.H.; Kheradmand Keysami, M.; Lari, H.R.

    2002-01-01

    Using wind energy for generating electricity in wind turbines is a good way for using renewable energies. It can also help to protect the environment. The main objective of this paper is dynamic modeling by energy method and simulation of a wind turbine aided by computer. In this paper, the equations of motion are extracted for simulating the system of wind turbine and then the behavior of the system become obvious by solving the equations. The turbine is considered with three blade rotor in wind direction, induced generator that is connected to the network and constant revolution for simulation of wind turbine. Every part of the wind turbine should be simulated for simulation of wind turbine. The main parts are blades, gearbox, shafts and generator

  1. Electrical Properties of PPy-Coated Conductive Fabrics for Human Joint Motion Monitoring

    Directory of Open Access Journals (Sweden)

    Jiyong Hu

    2016-03-01

    Full Text Available Body motion signals indicate several pathological features of the human body, and a wearable human motion monitoring system can respond to human joint motion signal in real time, thereby enabling the prevention and treatment of some diseases. Because conductive fabrics can be well integrated with the garment, they are ideal as a sensing element of wearable human motion monitoring systems. This study prepared polypyrrole conductive fabric by in situ polymerization, and the anisotropic property of the conductive fabric resistance, resistance–strain relationship, and the relationship between resistance and the human knee and elbow movements are discussed preliminarily.

  2. Contextualizing avian mortality: A preliminary appraisal of bird and bat fatalities from wind, fossil-fuel, and nuclear electricity

    International Nuclear Information System (INIS)

    Sovacool, Benjamin K.

    2009-01-01

    This article explores the threats that wind farms pose to birds and bats before briefly surveying the recent literature on avian mortality and summarizing some of the problems with it. Based on operating performance in the United States and Europe, this study offers an approximate calculation for the number of birds killed per kWh generated for wind electricity, fossil-fuel, and nuclear power systems. The study estimates that wind farms and nuclear power stations are responsible each for between 0.3 and 0.4 fatalities per gigawatt-hour (GWh) of electricity while fossil-fueled power stations are responsible for about 5.2 fatalities per GWh. While this paper should be respected as a preliminary assessment, the estimate means that wind farms killed approximately seven thousand birds in the United States in 2006 but nuclear plants killed about 327,000 and fossil-fueled power plants 14.5 million. The paper concludes that further study is needed, but also that fossil-fueled power stations appear to pose a much greater threat to avian wildlife than wind and nuclear power technologies.

  3. Contextualizing avian mortality: A preliminary appraisal of bird and bat fatalities from wind, fossil-fuel, and nuclear electricity

    Energy Technology Data Exchange (ETDEWEB)

    Sovacool, Benjamin K. [Energy Governance Program, Centre on Asia and Globalisation, Lee Kuan Yew School of Public Policy, National University of Singapore, Singapore 259772 (Singapore)], E-mail: bsovacool@nus.edu.sg

    2009-06-15

    This article explores the threats that wind farms pose to birds and bats before briefly surveying the recent literature on avian mortality and summarizing some of the problems with it. Based on operating performance in the United States and Europe, this study offers an approximate calculation for the number of birds killed per kWh generated for wind electricity, fossil-fuel, and nuclear power systems. The study estimates that wind farms and nuclear power stations are responsible each for between 0.3 and 0.4 fatalities per gigawatt-hour (GWh) of electricity while fossil-fueled power stations are responsible for about 5.2 fatalities per GWh. While this paper should be respected as a preliminary assessment, the estimate means that wind farms killed approximately seven thousand birds in the United States in 2006 but nuclear plants killed about 327,000 and fossil-fueled power plants 14.5 million. The paper concludes that further study is needed, but also that fossil-fueled power stations appear to pose a much greater threat to avian wildlife than wind and nuclear power technologies.

  4. Contextualizing avian mortality. A preliminary appraisal of bird and bat fatalities from wind, fossil-fuel, and nuclear electricity

    Energy Technology Data Exchange (ETDEWEB)

    Sovacool, Benjamin K. [Energy Governance Program, Centre on Asia and Globalisation, Lee Kuan Yew School of Public Policy, National University of Singapore, Singapore 259772 (Singapore)

    2009-06-15

    This article explores the threats that wind farms pose to birds and bats before briefly surveying the recent literature on avian mortality and summarizing some of the problems with it. Based on operating performance in the United States and Europe, this study offers an approximate calculation for the number of birds killed per kWh generated for wind electricity, fossil-fuel, and nuclear power systems. The study estimates that wind farms and nuclear power stations are responsible each for between 0.3 and 0.4 fatalities per gigawatt-hour (GWh) of electricity while fossil-fueled power stations are responsible for about 5.2 fatalities per GWh. While this paper should be respected as a preliminary assessment, the estimate means that wind farms killed approximately seven thousand birds in the United States in 2006 but nuclear plants killed about 327,000 and fossil-fueled power plants 14.5 million. The paper concludes that further study is needed, but also that fossil-fueled power stations appear to pose a much greater threat to avian wildlife than wind and nuclear power technologies. (author)

  5. Trailing edge devices to improve performance and increase lifetime of wind-electric water pumping systems

    Energy Technology Data Exchange (ETDEWEB)

    Vick, B.D.; Clark, R.N. [USDA-Agricultural Research Service, Bushland, TX (United States)

    1996-12-31

    Trailing edge flaps were applied to the blades of a 10 kW wind turbine used for water pumping to try to improve the performance and decrease the structural fatigue on the wind turbine. Most small wind turbines (10 kW and below) use furling (rotor turns out of wind similar to a mechanical windmill) to protect the wind turbine from overspeed during high winds. Some small wind turbines, however, do not furl soon enough to keep the wind turbine from being off line part of the time in moderately high wind speeds (10 - 16 m/s). As a result, the load is disconnected and no water is pumped at moderately high wind speeds. When the turbine is offline, the frequency increases rapidly often causing excessive vibration of the wind turbine and tower components. The furling wind speed could possibly be decreased by increasing the offset between the tower centerline and the rotor centerline, but would be a major and potentially expensive retrofit. Trailing edge flaps (TEF) were used as a quick inexpensive method to try to reduce the furling wind speed and increase the on time by reducing the rotor RPM. One TEF configuration improved the water pumping performance at moderately high wind speeds, but degraded the pumping performance at low wind speeds which resulted in little change in daily water volume. The other TEF configuration differed very little from the no flap configuration. Both TEF configurations however, reduced the rotor RPM in high wind conditions. The TEF, did not reduce the rotor RPM by lowering the furling wind speed as hoped, but apparently did so by increasing the drag which also reduced the volume of water pumped at the lower wind speeds. 6 refs., 9 figs.

  6. Kinetic-Scale Electric and Magnetic Field Fluctuations in the Solar Wind at 1 AU: THEMIS/ARTEMIS Observations

    Science.gov (United States)

    Salem, C. S.; Hanson, E.; Bonnell, J. W.; Chaston, C. C.; Bale, S. D.; Mozer, F.

    2017-12-01

    We present here an analysis of kinetic-scale electromagnetic fluctuations in the solar wind using data from THEMIS and ARTEMIS spacecraft. We use high-time resolution electric and magnetic field measurements, as well as density fluctuations, up to 128 samples per second, as well as particle burst plasma data during carefully selected solar wind intervals. We focus our analysis on a few such intervals spanning different values of plasma beta and angles between the local magnetic field and the radial Sun-Earth direction. We discuss the careful analysis process of characterizing and removing the different instrumental effects and noise sources affecting the electric and magnetic field data at those scales, above 0.1 Hz or so, above the breakpoint marking the start of the so-called dissipation range of solar wind turbulence. We compute parameters such as the electric to magnetic field ratio, the magnetic compressibility, magnetic helicity, and other relevant quantities in order to diagnose the nature of the fluctuations at those scales between the ion and electron cyclotron frequencies, extracting information on the dominant modes composing the fluctuations. We also discuss the presence and role of coherent structures in the measured fluctuations. The nature of the fluctuations in the dissipation or dispersive scales of solar wind turbulence is still debated. This observational study is also highly relevant to the current Turbulent Dissipation Challenge.

  7. SIZING AND COSTING OPTIMISATION OF A TYPICAL WIND/PV HYBRID ELECTRICITY GENERATION SYSTEM FOR A TYPICAL RESIDENTIAL BUILDING IN URBAN ARMIDALE NSW, AUSTRALIA

    Directory of Open Access Journals (Sweden)

    Yasser Maklad

    2014-04-01

    Full Text Available This study investigates the wind and solar electricity generation availability and potentiality for residential buildings in Armidale NSW, Australia. The main purpose of this study is to design an appropriate wind-PV hybrid system to cover the electricity consumption of typical residential buildings of various occupancy rates and relevant various average electrical daily consumption. In order to do achieve that, monthly average solar irradiance monthly average wind speed historical data observed at weather station belongs to the Australian bureau of meteorology in Armidale town over a fourteen years period from 1997–2010. Simulation of solar photovoltaic panels and wind turbines were conducted to obtain the optimal hybrid system sizing and best efficient with lowest cost. Correlations between the solar and wind power data were carried out on an hourly, daily, and monthly basis. It is shown that the hybrid system can be applied for the efficient and economic utilization of wind and solar renewable energy sources.

  8. Linear Extended State Observer-Based Motion Synchronization Control for Hybrid Actuation System of More Electric Aircraft

    Directory of Open Access Journals (Sweden)

    Xingjian Wang

    2017-10-01

    Full Text Available Moving towards the more electric aircraft (MEA, a hybrid actuator configuration provides an opportunity to introduce electromechanical actuator (EMA into primary flight control. In the hybrid actuation system (HAS, an electro-hydraulic servo actuator (EHSA and an EMA operate on the same control surface. In order to solve force fighting problem in HAS, this paper proposes a novel linear extended state observer (LESO-based motion synchronization control method. To cope with the problem of unavailability of the state signals required by the motion synchronization controller, LESO is designed for EHSA and EMA to observe the state variables. Based on the observed states of LESO, motion synchronization controllers could enable EHSA and EMA to simultaneously track the desired motion trajectories. Additionally, nonlinearities, uncertainties and unknown disturbances as well as the coupling term between EHSA and EMA can be estimated and compensated by using the extended state of the proposed LESO. Finally, comparative simulation results indicate that the proposed LESO-based motion synchronization controller could reduce significant force fighting between EHSA and EMA.

  9. A novel design of DC-AC electrical machine rotary converter for hybrid solar and wind energy applications

    Science.gov (United States)

    Mohammed, K. G.; Ramli, A. Q.; Amirulddin, U. A. U.

    2013-06-01

    This paper proposes the design of a new bi-directional DC-AC rotary converter machine to convert a d.c. voltage to three-phase voltage and vice-versa using a two-stage energy conversion machine. The rotary converter consists of two main stages which are combined into single frame. These two stages are constructed from three main electromagnetic components. The first inner electromagnetic component represents the input stage that enables the DC power generated by solar energy from photo-voltaic cells to be transformed by the second and third components electro-magnetically to produce multi-phase voltages at the output stage. At the same time, extra kinetic energy from wind, which is sufficiently available, can be added to existing torque on the second electromagnetic component. Both of these input energies will add up to the final energy generated at the output terminals. Therefore, the machine will be able to convert solar and wind energies to the output terminals simultaneously. If the solar energy is low, the available wind energy will be able to provide energy to the output terminals and at the same time charges the batteries which are connected as backup system. At this moment, the machine behaves as wind turbine. The energy output from the machine benefits from two energy sources which are solar and wind. At night when the solar energy is not available and also the load is low, the wind energy is able to charge the batteries and at the same time provides output electrical power to the remaining the load. Therefore, the proposed system will have high usage of available renewable energy as compared to separated wind or solar systems. MATLAB codes are used to calculate the required dimensions, the magnetic and electrical circuits parameters to design of the new bi-directional rotary converter machine.

  10. A novel design of DC-AC electrical machine rotary converter for hybrid solar and wind energy applications

    International Nuclear Information System (INIS)

    Mohammed, K G; Ramli, A Q; Amirulddin, U A U

    2013-01-01

    This paper proposes the design of a new bi-directional DC-AC rotary converter machine to convert a d.c. voltage to three-phase voltage and vice-versa using a two-stage energy conversion machine. The rotary converter consists of two main stages which are combined into single frame. These two stages are constructed from three main electromagnetic components. The first inner electromagnetic component represents the input stage that enables the DC power generated by solar energy from photo-voltaic cells to be transformed by the second and third components electro-magnetically to produce multi-phase voltages at the output stage. At the same time, extra kinetic energy from wind, which is sufficiently available, can be added to existing torque on the second electromagnetic component. Both of these input energies will add up to the final energy generated at the output terminals. Therefore, the machine will be able to convert solar and wind energies to the output terminals simultaneously. If the solar energy is low, the available wind energy will be able to provide energy to the output terminals and at the same time charges the batteries which are connected as backup system. At this moment, the machine behaves as wind turbine. The energy output from the machine benefits from two energy sources which are solar and wind. At night when the solar energy is not available and also the load is low, the wind energy is able to charge the batteries and at the same time provides output electrical power to the remaining the load. Therefore, the proposed system will have high usage of available renewable energy as compared to separated wind or solar systems. MATLAB codes are used to calculate the required dimensions, the magnetic and electrical circuits parameters to design of the new bi-directional rotary converter machine.

  11. The development of convective instability, wind shear, and vertical motion in relation to convection activity and synoptic systems in AVE 4

    Science.gov (United States)

    Davis, J. G.; Scoggins, J. R.

    1981-01-01

    Data from the Fourth Atmospheric Variability Experiment were used to investigate conditions/factors responsible for the development (local time rate-of-change) of convective instability, wind shear, and vertical motion in areas with varying degrees of convective activity. AVE IV sounding data were taken at 3 or 6 h intervals during a 36 h period on 24-25 April 1975 over approximately the eastern half of the United States. An error analysis was performed for each variable studied.

  12. Valence of wind power, photovoltaic and peak-load power plants as a part of the entire electricity system

    International Nuclear Information System (INIS)

    Schüppel, A.

    2014-01-01

    The transition to a higher share of renewable energy sources in the electricity sector leads to a multitude of challenges for the current electricity system. Within this thesis, the development of wind power and photovoltaics generation capacities in Germany is analysed based on the evaluation of technical and economic criteria. In order to derive those criteria, different scenarios with a separated and combined increase of wind and photovoltaics capacity are simulated using the model ATLANTIS. The results are compared to a reference scenario without additional wind and PV capacities. Furthermore, the value and functionality of the energy only market based on economic methods, as well as the value of peak load power plants based on opportunity costs are determined. The results of this thesis show, that the current market system is able to gain an additional annual welfare of four to six billion Euro at the best. This result shows that the task of optimising the power plant dispatch is well fulfilled by the current market design. However, the effects, e.g. fuel costs, which may influence this margin. The value of wind power and photovoltaics within the overall electricity system can be derived from the effort which is necessary to integrate these generation technologies into the existing system, and the changes in total costs of electricity generation. Based on the evaluation of time dependencies (seasonality of energy yield from wind and PV) as well as the development of total generation costs, the conclusion can be drawn that wind power is the more suitable RES generation technology for Germany. However, when it comes to grid integration measures, PV shows better results due to a higher generation potential in Southern Germany, which leads to a higher degree of utilisation. Therefore, there is no need to transport electricity from Northern to Southern Germany as it is the case with wind power. A common expansion of wind power and photovoltaics even shows slight

  13. Adding concentrated solar power plants to wind farms to achieve a good utility electrical load match

    Science.gov (United States)

    Texas has the greatest installed wind turbine capacity of any state in the United States, the percentage of wind capacity approaches 10% of the utilities capacity (in 2010 the total wind generated capacity in Texas was 8%). It is becomimg increasingly difficult for the utility to balance the elec...

  14. A Multi-Objective Optimization Framework for Offshore Wind Farm Layouts and Electric Infrastructures

    Directory of Open Access Journals (Sweden)

    Silvio Rodrigues

    2016-03-01

    Full Text Available Current offshore wind farms (OWFs design processes are based on a sequential approach which does not guarantee system optimality because it oversimplifies the problem by discarding important interdependencies between design aspects. This article presents a framework to integrate, automate and optimize the design of OWF layouts and the respective electrical infrastructures. The proposed framework optimizes simultaneously different goals (e.g., annual energy delivered and investment cost which leads to efficient trade-offs during the design phase, e.g., reduction of wake losses vs collection system length. Furthermore, the proposed framework is independent of economic assumptions, meaning that no a priori values such as the interest rate or energy price, are needed. The proposed framework was applied to the Dutch Borssele areas I and II. A wide range of OWF layouts were obtained through the optimization framework. OWFs with similar energy production and investment cost as layouts designed with standard sequential strategies were obtained through the framework, meaning that the proposed framework has the capability to create different OWF layouts that would have been missed by the designers. In conclusion, the proposed multi-objective optimization framework represents a mind shift in design tools for OWFs which allows cost savings in the design and operation phases.

  15. Expensive wind mill. Must we build in France wind mills connected to the electric network?; Dispendieuses eoliennes. Faut-il edifier en France des eoliennes reccordees au reseau electrique general?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    Facing the increase of the electric power production in an environmental quality context, the authors wonder about the increase of the wind power part. It seems that the wind energy, which will save only 2,4% of the nuclear fuel, is a bad solution in terms of economy and environment. Many data on cast and capacity illustrate this analysis. (A.L.B.)

  16. A decentralized charging control strategy for plug-in electric vehicles to mitigate wind farm intermittency and enhance frequency regulation

    Science.gov (United States)

    Luo, Xiao; Xia, Shiwei; Chan, Ka Wing

    2014-02-01

    This paper proposes a decentralized charging control strategy for a large population of plug-in electric vehicles (PEVs) to neutralize wind power fluctuations so as to improve the regulation of system frequency. Without relying on a central control entity, each PEV autonomously adjusts its charging or discharging power in response to a communal virtual price signal and based on its own urgency level of charging. Simulation results show that under the proposed charging control, the aggregate PEV power can effectively neutralize wind power fluctuations in real-time while differential allocation of neutralization duties among the PEVs can be realized to meet the PEV users' charging requirements. Also, harmful wind-induced cyclic operations in thermal units can be mitigated. As shown in economic analysis, the proposed strategy can create cost saving opportunities for both PEV users and utility.

  17. Overview, status and outline of the new IEC 61400-27. Electrical simulation models for wind power generation

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, Poul [Wiley (John) and Sons, Inc., New York, NY (United States). Journal Dept.; Andresen, Bjoern [Siemens Wind Power (Denmark); Fortmann, Jens [RE-Power Systems AG (Germany); Johansen, Knud [Energinet.dk (Denmark); Pourbeik, Pouyan [EPRI (United States)

    2011-07-01

    This paper presents the ongoing work in Working Group (WG) 27 of IEC Technical Committee (TC) 88 developing a standard IEC 61400-27 for 'Electrical simulation models for wind power generation'. The purpose of the standardization work is to define generic simulation models for wind turbines and wind power plants, which are intended for power systems stability analyses. Thus, the models will be applicable for dynamic simulations of power system events such as faults, loss of generation or loads and switching of lines. The paper presents the actual status of the IEC TC88 WG27 work. Some of the challenges encountered during the process of the development of the standard are described, and expected outcome of the standard is also presented. (orig.)

  18. Quantifying the Opportunity Space for Future Electricity Generation: An Application to Offshore Wind Energy in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Marcy, Cara [National Renewable Energy Lab. (NREL), Golden, CO (United States); Beiter, Philipp [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    This report provides a high-level indicator of the future electricity demand for additional electric power generation that is not met by existing generation sources between 2015 and 2050. The indicator is applied to coastal regions, including the Great Lakes, to assess the regional opportunity space for offshore wind. An assessment of opportunity space can be a first step in determining the prospects and the system value of a technology. The metric provides the maximal amount of additional generation that is likely required to satisfy load in future years.

  19. A hybrid solar photovoltaic-wind turbine-Rankine cycle for electricity generation in Turkish Republic of Northern Cyprus

    Directory of Open Access Journals (Sweden)

    Samuel Asumadu-Sarkodie

    2016-12-01

    Full Text Available This paper presents an energy demand model by designing a hybrid solar-wind-thermal power generation system of the Turkish Republic of Northern Cyprus, a promising substitute for the expensive battery banks. The study models the future energy demand of Turkish Republic of Northern Cyprus based on the IPCC emissions scenario A1B and A2 by designing a new hybrid solar-wind-thermal power system that satisfies the current and future requirements of firm capacity during peak periods. The study suggests an improvement in a hybrid solar-wind-thermal power system performance by predicting reliable outputs that can integrate renewable energy technologies to conventional power generation. The energy consumption prediction model emphasizes the energy requirement that has a growing demand from 300 to 400 GWh in scenario A1B and 150–450 GWh in scenario A2 from 2010 to 2050. The proposed design can meet 400 GWh of electricity demand in TRNC based on IPCC scenario A1B and 450 GWh of electricity demand in TRNC based on IPCC scenario A2. The percentage contribution of solar, wind and thermal energy for 2010, 2020, 2030, 2040 and 2050 are presented along with CO2 emissions and water consumption for each of the years.

  20. Fractional Slot Concentrated Windings: A New Method to Manage the Mutual Inductance between Phases in Three-Phase Electrical Machines and Multi-Star Electrical Machines

    Directory of Open Access Journals (Sweden)

    Olivier Barre

    2015-06-01

    Full Text Available Mutual inductance is a phenomenon caused by the circulation of the magnetic flux in the core of an electrical machine. It is the result of the effect of the current flowing in one phase on the other phases. In conventional three-phase machines, such an effect has no influence on the electrical behaviour of the device. Although these machines are powered by power inverters, no problem should occur. The result is not the same for multi-star machines. If these machines are using a conventional winding structure, namely distributed windings, and are powered by voltage source converters, current ripples appear in the power supply lines. These current ripples are related to magnetic couplings between the stars. Designers should check these current ripples in order to stay within the limits imposed by the specifications. These electric current disturbances also provide torque ripples. With concentrated windings, a new degree of freedom appears; the configuration—number of slots/number of poles—can have a positive impact. The circulation of the magnetic flux is the initial phenomenon that produces the mutual inductance. The main goal of this discussion is to describe a design method that is able to produce not only a machine with low mutual inductance between phases, but also a multi-star machine where the stars and the phases are magnetically decoupled or less coupled. This discussion only takes into account the machines that use permanent magnets mounted on the rotor surface. This article is part of a study aimed at designing a high efficiency generator using fractional-slot concentrated-windings (FSCW.

  1. Electric solar-wind sail for asteroid touring missions and planetary protection

    Science.gov (United States)

    Janhunen, P.

    2014-07-01

    The electric solar-wind sail (electric sail, E-sail [1,2]) is a relatively new concept for moving around in the solar system without consuming propellant and by using the thrust provided by the natural solar wind to produce propulsion. The E-sail is based on deploying, using the centrifugal force, a set of long, thin metallic tethers and charging them to high positive voltage by actively removing negative charge from the system by an electron gun. To make the tethers resistant towards inevitable wire cuts by micrometeoroids, they must be made by bonding from multiple (typically 4) thin (25--50 μ m) aluminium wires. Production of the tethers was a technical challenge which was recently overcome. According to present numerical estimates, the E-sail could produce up to 1 N of propellantless thrust out of less than 200 kg package which is enough to give characteristic acceleration of 1 mm/s^2 to a spacecraft weighing 1 tonne, thus producing 30 km/s of delta-v per year. The thrust scales as ˜ 1/r where r is the solar distance. There are ways to control and vector the thrust enough to enable inward and outward spiralling missions in the solar system. The E-sail working principle has been indirectly measured in a laboratory, and ESTCube-1 CubeSat experiment is underway in orbit (in late March 2014 it was waiting to be started) to measure the E-sail thrust acting on a short 10-m long tether. A full-scale mission requires ˜ 1000 km of tether altogether (weighing ˜10 kg). The production of a 1-km piece of tether has been demonstrated in laboratory [3]. If the E-sail holds up its present promise, it would be ideally suited for asteroid missions because it enables production of similar level of thrust than ion engines, but needs only a small fraction of the electric power and never runs out of propellant because it does not use any (the ''propellant'' being the natural solar-wind plasma flow). Here we consider especially a mission which would tour the asteroid belt for a

  2. Impact of equalizing currents on losses and torque ripples in electrical machines with fractional slot concentrated windings

    Science.gov (United States)

    Toporkov, D. M.; Vialcev, G. B.

    2017-10-01

    The implementation of parallel branches is a commonly used manufacturing method of the realizing of fractional slot concentrated windings in electrical machines. If the rotor eccentricity is enabled in a machine with parallel branches, the equalizing currents can arise. The simulation approach of the equalizing currents in parallel branches of an electrical machine winding based on magnetic field calculation by using Finite Elements Method is discussed in the paper. The high accuracy of the model is provided by the dynamic improvement of the inductances in the differential equation system describing a machine. The pre-computed table flux linkage functions are used for that. The functions are the dependences of the flux linkage of parallel branches on the branches currents and rotor position angle. The functions permit to calculate self-inductances and mutual inductances by partial derivative. The calculated results obtained for the electric machine specimen are presented. The results received show that the adverse combination of design solutions and the rotor eccentricity leads to a high value of the equalizing currents and windings heating. Additional torque ripples also arise. The additional ripples harmonic content is not similar to the cogging torque or ripples caused by the rotor eccentricity.

  3. New Approaches for Very Short-term Steady-State Analysis of An Electrical Distribution System with Wind Farms

    Directory of Open Access Journals (Sweden)

    Antonio Bracale

    2010-04-01

    Full Text Available Distribution networks are undergoing radical changes due to the high level of penetration of dispersed generation. Dispersed generation systems require particular attention due to their incorporation of uncertain energy sources, such as wind farms, and due to the impacts that such sources have on the planning and operation of distribution networks. In particular, the foreseeable, extensive use of wind turbine generator units in the future requires that distribution system engineers properly account for their impacts on the system. Many new technical considerations must be addressed, including protection coordination, steady-state analysis, and power quality issues. This paper deals with the very short-term, steady-state analysis of a distribution system with wind farms, for which the time horizon of interest ranges from one hour to a few hours ahead. Several wind-forecasting methods are presented in order to obtain reliable input data for the steady-state analysis. Both deterministic and probabilistic methods were considered and used in performing deterministic and probabilistic load-flow analyses. Numerical applications on a 17-bus, medium-voltage, electrical distribution system with various wind farms connected at different busbars are presented and discussed.

  4. Electric traction motion power and energy supply : basics and practical experience

    CERN Document Server

    Steimel, Andreas

    2011-01-01

    This book has evolved from the lecture series ""Elektrische Bahnen" (""Electric railways") which has been held at Ruhr-Universität Bochum since 1996. Its primary audience are students of electrical energy technologies, control engineering and mechanical engineering as well as young engineers of electrical engineering, especially in the fields of power electronics, in railway industry and in railway-operating companies. The book intends to convey mechanical fundamentals of electric railway propulsion, which includes rail-bound guidance, transmission of traction effort from wheel to rail under t

  5. Impact of large scale wind power on the Nordic electricity system

    International Nuclear Information System (INIS)

    Holttinen, Hannele

    2006-01-01

    Integration costs of wind power depend on how much wind power and where, and the power system: load, generation flexibility, interconnections. When wind power is added to a large interconnected power system there is considerable smoothing effect for the production. Increase of reserve requirements will stay at a low level. 10 percent penetration of wind power is not a problem in Nordic countries, as long as wind power is built to all 4 countries. Increasing the share of wind power will increase the integration costs. 20 percent penetration would need more flexibility in the system. That will not happen in the near future for Nordel, and the power system will probably also contain more flexible elements at that stage, like producing fuel for vehicles (ml)

  6. Questionnaire Study for The Use of Solar Energy and Wind Energy for The Generation of Electricity in Kuwait

    International Nuclear Information System (INIS)

    Tarawneh, Sultan; Rireh, Mohmd; Al-Razzi, Met'eb

    2015-01-01

    This research aims to study the acceptance of real management of designing electrical generation plants that work using solar energy and wind energy, to explain the benefits for the decision makers of the use of the solar energy and wind energy, and to define the most important obstacles that hinder the use of solar energy in generating electricity in spite of fulfilling the environmental conditions as clean energy and renewing energy contribute to sustainability of natural resources. The descriptive methodology was used by going back to reference material including books, and scientific journals and periodicals as well as scientific researches to identify the real management and design of electrical plant generation using solar energy and wind energy. A questionnaire was distributed among the study sample that was composed of the engineers working in energy field and electrical generation plants, the general institute for environment, Kuwait Institute for Scientific Research, and Kuwait Society of Engineers. 203 responses were received from the study sample. Results of the study showed the presence of obstacles and special problems related to the use of solar energy that face the decision makers with regard to the ability for acquiring important advanced technology and the huge financial support and the partnership of the private sector and training of unskilled human resources. And it was declared that there is a huge focus and attention in generation electrical energy from fossil fuel because of its presence and sustainability in investment in this field and the ability to fulfill the needs of the local market from energy.(author)

  7. Careers in Wind Energy

    Science.gov (United States)

    Liming, Drew; Hamilton, James

    2011-01-01

    As a common form of renewable energy, wind power is generating more than just electricity. It is increasingly generating jobs for workers in many different occupations. Many workers are employed on wind farms: areas where groups of wind turbines produce electricity from wind power. Wind farms are frequently located in the midwestern, western, and…

  8. Assessment of wind energy potential and optimal electricity generation in Borj-Cedria, Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Dahmouni, A.W.; Kerkeni, C. [Laboratoire de Maitrise de l' Energie Eolienne et de Valorisation Energetique des Dechets, Centre de Recherche et des Technologies de l' Energie, Technopole de Borj-Cedria, BP 95, Hammam Lif 2050 (Tunisia); Ben Salah, M. [Laboratoire des Procedees Thermiques, Centre de Recherche et technologies de l' Energie, Centre de Recherche et des Technologies de l' Energie, Technopole de Borj-Cedria, BP 95 Hammam Lif 2050 (Tunisia); Askri, F.; Ben Nasrallah, S. [Laboratoire d' Etudes des Systemes Thermiques et Energetiques, Ecole Nationale d' Ingenieurs de Monastir, avenue Ibn El Jazzar 5019, Monastir (Tunisia)

    2011-01-15

    In the last century, several climate changes have been observed in regions all over the world. The main cause of these climatic changes is the rise of fossil fuel uses, which is due to the important demographic and industrial development. These negative effects have forced scientists to draw attention to renewable energy sources, which are the most suitable solution in the future. In this paper, wind energy potential was estimated using the wind speed data collected by two meteorological stations installed in the Centre of Research and Technologies of Energy (CRTEn) in the Borj-Cedria area. The data collected at 30, 20 and 10 m height during 2008 and 2009, have permitted us to estimate the seasonal mean wind speed, wind speed distribution and wind power density. The results have been used to estimate the net energy output of seven 1.5 MW wind turbines with taken account the air density correction and the power losses in wind farm. This comparative simulation shows difference in wind generators production and allows us to choose the best wind turbine adapted to the site conditions. (author)

  9. Large-scale integration of off-shore wind power and regulation strategies of cogeneration plants in the Danish electricity system

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg

    2005-01-01

    The article analyses how the amount of a small-scale CHP plants and heat pumps and the regulation strategies of these affect the quantity of off-shore wind power that may be integrated into Danish electricity supply......The article analyses how the amount of a small-scale CHP plants and heat pumps and the regulation strategies of these affect the quantity of off-shore wind power that may be integrated into Danish electricity supply...

  10. Integration of the Taber wind power project into the Alberta interconnected electric system : practical experience in design, testing and operations

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, S. [ENMAX Power Corp., Calgary, AB (Canada); Wachtel, S. [Enercon GmbH, Berlin (Germany)

    2008-07-01

    This presentation discussed Alberta's ENMAX Taber wind power project. The farm was commissioned in 2007, and is comprised of 37 ENERCON E-70 turbines rated at 2.2 MW each. The turbines have an advanced blade design and variable speed operation with direct drive and full-scale AC-DC-AC power electronics. The turbines also use flexible AC transmission systems (FACTS). Due to the fact that good winds in Alberta are located far from major electrical loads, wind farms in the province are often required to perform like dispatchable generation plants. Reactive power is used to set up electromagnetic fields that enable current flow and charge certain electrical elements. Reactive power has a strong impact on voltage regulation in high voltage networks. Alberta's interconnection standards require continuous reactive power capability. The ENERCON E-70 power capability has a wide reactive power range with an actual measured response and a range fully available at MW outputs greater than 20 per cent. Overall facility response is influenced by a number of factors. Actual measured response at the Taber facility is optimized to within 1 second. A single central voltage controller is used per wind farm. Testing at the Taber farm has resulted in critical low voltage alarms on adjacent transmission lines. Close coordination with the Alberta Electricity System Operator (AESO) has been required to avert potential power outages in the area. It was concluded that a lack of compliance testing can result in difficulties complying with interconnection standards. tabs., figs.

  11. How does market power affect the impact of large scale wind investment in 'energy only' wholesale electricity markets?

    International Nuclear Information System (INIS)

    Browne, Oliver; Poletti, Stephen; Young, David

    2015-01-01

    In the short run, it is well known that increasing wind penetration is likely to reduce spot market electricity prices due to the merit order effect. The long run effect is less clear because there will be a change in new capacity investment in response to the wind penetration. In this paper we examine the interaction between capacity investment, wind penetration and market power by first using a least-cost generation expansion model to simulate capacity investment with increasing amounts of wind generation, and then using a computer agent-based model to predict electricity prices in the presence of market power. We find the degree to which firms are able to exercise market power depends critically on the ratio of capacity to peak demand. For our preferred long run generation scenario we show market power increases for some periods as wind penetration increases however the merit order counteracts this with the results that prices overall remain flat. Returns to peakers increase significantly as wind penetration increases. The market power in turn leads to inefficient dispatch which is exacerbated with large amounts of wind generation. - Highlights: • Increasing investment in wind generation is analyzed using an agent based model. • In an energy only market, increased total capacity reduces market power. • Increasing wind penetration results in more market power in some periods. • Market power causes dispatch inefficiencies, which grow as wind capacity increases.

  12. Market and regulatory aspects of trans-national offshore electricity networks for wind power interconnection

    NARCIS (Netherlands)

    Roggenkamp, Martha M.; Hendriks, Ralph L.; Ummels, Bart C.; Kling, Wil L.

    Subsea cable connections are an essential part of offshore wind power projects. Apart from direct connections between an offshore wind park to the national grid, several alternatives can be envisaged, including the connection to interconnectors between countries or direct connection to a country

  13. Evaluation of power control with different electrical and control concept of wind farm

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela

    This report investigates the impact of wind power in large power systems. The motivation for this investigation is the ever-increasing wind energy penetration into the power systems throughout the world. A generic large power system model delivered by the Danish Transmission System Operator Energi...

  14. Study of the Advantages of Internal Permanent Magnet Drive Motor with Selectable Windings for Hybrid-Electric Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Otaduy, P.J.; Hsu, J.S.; Adams, D.J.

    2007-11-30

    This report describes research performed on the viability of changing the effectively active number of turns in the stator windings of an internal permanent magnet (IPM) electric motor to strengthen or weaken the magnetic fields in order to optimize the motor's performance at specific operating speeds and loads. Analytical and simulation studies have been complemented with research on switching mechanisms to accomplish the task. The simulation studies conducted examine the power and energy demands on a vehicle following a series of standard driving cycles and the impact on the efficiency and battery size of an electrically propelled vehicle when it uses an IPM motor with turn-switching capabilities. Both full driving cycle electric propulsion and propulsion limited starting from zero to a set speed have been investigated.

  15. Integrating massiv wind power in the electric system. Acciona experience in Spain

    Energy Technology Data Exchange (ETDEWEB)

    Giraut Ruso, E.; Ruiz Guillen, J.; Quinonez-Varela, G.; Armendariz Otazu, I.; Navarrete Pablo-Romero, A.; Moreira Prada, C.; Alday Aracama, G.; Sanchez Ardoiz, R.; Moreno Fernandez, J. [Acciona Energia, Sarriguren (Spain)

    2009-07-01

    In this paper, the existing operational procedures applicable to wind and renewable generation in Spain are presented. These include remote control of renewable generators and their interaction with the TSO's Control Centre: energy production forecast and market integration, and voltage and reactive power control. Acciona Energia, as one of the largest operator and owner of renewable assets in Spain (particularly wind power plants), hat been a major player in the implementation of measures to comply with these procedures. For instance, it has worked closely with the TSO and the wind sector to help formulating Grid Code requirements, it has designed new wind turbine technologies to fulfil them and it has deployed innovative solutions to adapt older wind generators and plants to new standards (retrofitting). Acciona's experiences and technical solutions to these challenges are thoroughly discussed. (orig.)

  16. Co-Design Based Lateral Motion Control of All-Wheel-Independent-Drive Electric Vehicles with Network Congestion

    Directory of Open Access Journals (Sweden)

    Wanke Cao

    2017-10-01

    Full Text Available All-wheel-independent-drive electric vehicles (AWID-EVs have considerable advantages in terms of energy optimization, drivability and driving safety due to the remarkable actuation flexibility of electric motors. However, in their current implementations, various real-time data in the vehicle control system are exchanged via a controller area network (CAN, which causes network congestion and network-induced delays. These problems could lead to systemic instability and make the system integration difficult. The goal of this paper is to provide a design methodology that can cope with all these challenges for the lateral motion control of AWID-EVs. Firstly, a continuous-time model of an AWID-EV is derived. Then an expression for determining upper and lower bounds on the delays caused by CAN is presented and with which a discrete-time model of the closed-loop CAN system is derived. An expression on the bandwidth utilization is introduced as well. Thirdly, a co-design based scheme combining a period-dependent linear quadratic regulator (LQR and a dynamic period scheduler is designed for the resulting model and the stability criterion is also derived. The results of simulations and hard-in-loop (HIL experiments show that the proposed methodology can effectively guarantee the stability of the vehicle lateral motion control while obviously declining the network congestion.

  17. Revisiting short-term price and volatility dynamics in day-ahead electricity markets with rising wind power

    International Nuclear Information System (INIS)

    Li, Yuanjing

    2015-01-01

    This paper revisits the short-term price and volatility dynamics in day-ahead electricity markets in consideration of an increasing share of wind power, using an example of the Nord Pool day-ahead market and the Danish wind generation. To do so, a GARCH process is applied, and market coupling and the counterbalance effect of hydropower in the Scandinavian countries are additionally accounted for. As results, we found that wind generation weakly dampens spot prices with an elasticity of 0.008 and also reduces price volatility with an elasticity of 0.02 in the Nordic day-ahead market. The results shed lights on the importance of market coupling and interactions between wind power and hydropower in the Nordic system through cross-border exchanges, which play an essential role in price stabilization. Additionally, an EGARCH specification confirms an asymmetric influence of the price innovations, whereby negative shocks produce larger volatility in the Nordic spot market. While considering heavy tails in error distributions can improve model fits significantly, the EGARCH model outperforms the GARCH model on forecast evaluations. (author)

  18. Estimating the electricity prices, generation costs and CO2 emissions of large scale wind energy exports from Ireland to Great Britain

    International Nuclear Information System (INIS)

    Cleary, Brendan; Duffy, Aidan; Bach, Bjarne; Vitina, Aisma; O’Connor, Alan; Conlon, Michael

    2016-01-01

    The share of wind generation in the Irish and British electricity markets is set to increase by 2020 due to renewable energy (RE) targets. The United Kingdom (UK) and Ireland have set ambitious targets which require 30% and 40% of electricity demand to come from RE, mainly wind, by 2020, respectively. Ireland has sufficient indigenous onshore wind energy resources to exceed the RE target, while the UK faces uncertainty in achieving its target. A possible solution for the UK is to import RE directly from large scale onshore and offshore wind energy projects in Ireland; this possibility has recently been explored by both governments but is currently on hold. Thus, the aim of this paper is to estimate the effects of large scale wind energy in the Irish and British electricity markets in terms of wholesale system marginal prices, total generation costs and CO 2 emissions. The results indicate when the large scale Irish-based wind energy projects are connected directly to the UK there is a decrease of 0.6% and 2% in the Irish and British wholesale system marginal prices under the UK National Grid slow progression scenario, respectively. - Highlights: • Modelling the Irish and British electricity markets. • Investigating the impacts of large scale wind energy within the markets. • Results indicate a reduction in wholesale system marginal prices in both markets. • Decrease in total generation costs and CO 2 emissions in both markets.

  19. Enhanced Forecasting Approach for Electricity Market Prices and Wind Power Data Series in the Short-Term

    Directory of Open Access Journals (Sweden)

    Gerardo J. Osório

    2016-08-01

    Full Text Available The uncertainty and variability in electricity market price (EMP signals and players’ behavior, as well as in renewable power generation, especially wind power, pose considerable challenges. Hence, enhancement of forecasting approaches is required for all electricity market players to deal with the non-stationary and stochastic nature of such time series, making it possible to accurately support their decisions in a competitive environment with lower forecasting error and with an acceptable computational time. As previously published methodologies have shown, hybrid approaches are good candidates to overcome most of the previous concerns about time-series forecasting. In this sense, this paper proposes an enhanced hybrid approach composed of an innovative combination of wavelet transform (WT, differential evolutionary particle swarm optimization (DEEPSO, and an adaptive neuro-fuzzy inference system (ANFIS to forecast EMP signals in different electricity markets and wind power in Portugal, in the short-term, considering only historical data. Test results are provided by comparing with other reported studies, demonstrating the proficiency of the proposed hybrid approach in a real environment.

  20. Electric car with solar and wind energy may change the environment and economy: A tool for utilizing the renewable energy resource

    Science.gov (United States)

    Liu, Quanhua

    2014-01-01

    Energy and environmental issues are among the most important problems of public concern. Wind and solar energy may be one of the alternative solutions to overcome energy shortage and to reduce greenhouse gaseous emission. Using electric cars in cities can significantly improve the air quality there. Through our analyses and modeling on the basis of the National Centers for Environment Prediction data we confirm that the amount of usable solar and wind energy far exceeds the world's total energy demand, considering the feasibility of the technology being used. Storing the surplus solar and wind energy and then releasing this surplus on demand is an important approach to maintaining uninterrupted solar- and wind-generated electricity. This approach requires us to be aware of the available solar and wind energy in advance in order to manage their storage. Solar and wind energy depends on weather conditions and we know weather forecasting. This implies that solar and wind energy is predictable. In this article, we demonstrate how solar and wind energy can be forecasted. We provide a web tool that can be used by all to arrive at solar and wind energy amount at any location in the world. The tool is available at http://www.renewableenergyst.org. The website also provides additional information on renewable energy, which is useful to a wide range of audiences, including students, educators, and the general public.

  1. The impacts of electricity dispatch protocols on the emission reductions due to wind power and carbon tax.

    Science.gov (United States)

    Yu, Yang; Rajagopal, Ram

    2015-02-17

    Two dispatch protocols have been adopted by electricity markets to deal with the uncertainty of wind power but the effects of the selection between the dispatch protocols have not been comprehensively analyzed. We establish a framework to compare the impacts of adopting different dispatch protocols on the efficacy of using wind power and implementing a carbon tax to reduce emissions. We suggest that a market has high potential to achieve greater emission reduction by adopting the stochastic dispatch protocol instead of the static protocol when the wind energy in the market is highly uncertain or the market has enough adjustable generators, such as gas-fired combustion generators. Furthermore, the carbon-tax policy is more cost-efficient for reducing CO2 emission when the market operates according to the stochastic protocol rather than the static protocol. An empirical study, which is calibrated according to the data from the Electric Reliability Council of Texas market, confirms that using wind energy in the Texas market results in a 12% CO2 emission reduction when the market uses the stochastic dispatch protocol instead of the 8% emission reduction associated with the static protocol. In addition, if a 6$/ton carbon tax is implemented in the Texas market operated according to the stochastic protocol, the CO2 emission is similar to the emission level from the same market with a 16$/ton carbon tax operated according to the static protocol. Correspondingly, the 16$/ton carbon tax associated with the static protocol costs 42.6% more than the 6$/ton carbon tax associated with the stochastic protocol.

  2. A multi-objective optimization framework for offshore wind farm layouts and electric infrastructures

    NARCIS (Netherlands)

    S. Rodrigues (Silvio); C. Restrepo (Carlos); G. Katsouris (George); R. Teixeira Pinto (Rodrigo); M. Soleimanzadeh (Maryam); P.A.N. Bosman (Peter); P. Bauer (Pavol)

    2016-01-01

    textabstractCurrent offshore wind farms (OWFs) design processes are based on a sequential approach which does not guarantee system optimality because it oversimplifies the problem by discarding important interdependencies between design aspects. This article presents a framework to integrate,

  3. Results from operation and research of the experimental wind farm of the Dutch electricity generating board

    International Nuclear Information System (INIS)

    Toussaint, P.; Hutting, H.K.; Mortier, M.; Cleijne, J.W.

    1992-01-01

    This combined paper consists of four parts. The order of the above authors corresponds to the order of the parts. The first part deals with the operational experience of the farm. It reports an average capacity factor of 24% and an availability of 90%. The second part reports measured power losses due to wake effects, while the third part shows wind velocity deficits and turbulence characteristics within a wake. In the last part the application of a wind farm controller is demonstrated. (au)

  4. A Micro-scale Wind Turbine Fed BLDC Motor for Electric Vehicle Drive Application

    OpenAIRE

    Kazraji, Saeed Masoumi; Khanabdal, Saheb; Soflaye, Ramin Bavil; Sabahi, Mehran

    2016-01-01

    In this paper a permanent magnet brushless dc motor (PMBLDCM) based driver with a wind-generator (WG) in maximum power point tracking (MPPT) condition is proposed. The proposed system has a high efficiency buck-type dc/dc converter and control unit running the MPPT function. The WG optimal power characteristic and wind speed measuring data are not required while the WG works in variable speed mode, therefore higher reliability, simplicity, lower cost and less mechanical Tension of the WG are ...

  5. Record of Decision for the Electrical Interconnection of the Windy Point Wind Energy Project.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    2006-11-01

    The Bonneville Power Administration (BPA) has decided to offer contract terms for interconnection of 250 megawatts (MW) of power to be generated by the proposed Windy Point Wind Energy Project (Wind Project) into the Federal Columbia River Transmission System (FCRTS). Windy Point Partners, LLC (WPP) propose to construct and operate the proposed Wind Project and has requested interconnection to the FCRTS. The Wind Project will be interconnected at BPA's Rock Creek Substation, which is under construction in Klickitat County, Washington. The Rock Creek Substation will provide transmission access for the Wind Project to BPA's Wautoma-John Day No.1 500-kilovolt (kV) transmission line. BPA's decision to offer terms to interconnect the Wind Project is consistent with BPA's Business Plan Final Environmental Impact Statement (BP EIS) (DOE/EIS-0183, June 1995), and the Business Plan Record of Decision (BP ROD, August 15, 1995). This decision thus is tiered to the BP ROD.

  6. Cooperation of electrically stimulated muscle and pneumatic muscle to realize RUPERT bi-directional motion for grasping.

    Science.gov (United States)

    Xikai Tu; Jiping He; Yue Wen; Jian Huang; Xinhan Huang; Hailong Huang; Meng Guo; Yong Yuan

    2014-01-01

    Robot-assisted rehabilitation is an active area of research to meet the demand of repetitive therapy in stroke rehabilitation. Robotic upper-extremity repetitive trainer (RUPERT) with its unidirectional pneumatic muscle actuation (PMA) can be used by most stroke patients that have difficulty moving in one direction because of a weak agonist or hyperactive antagonist. In this research, to broaden the usage of RUPERT, we not only add grasping functionality to the rehabilitation robot with the help of surface Functional Electrical Stimulation (FES) but also realize the robot joint bi-directional motion by using a PMA in cooperation with surface FES evoked paralyzed muscle force. This integrative rehabilitation strategy is explored for training patients to practice coordinated reaching and grasping functions. The effectiveness of this FES electrically evoked bio-actuator way is verified through a method that separates the mixed electromyogram (MEMG) into the electrically evoked electromyogram (EEMG) and voluntary electromyogram (VEMG). This is a promising approach to alleviate the size and mechanical complexity of the robot, thereby the cost of the joint bi-directional actuator rehabilitation robot by means of their own characteristics of stroke subjects.

  7. Transient Dynamics of Electric Power Systems: Direct Stability Assessment and Chaotic Motions

    Science.gov (United States)

    Chu, Chia-Chi

    A power system is continuously experiencing disturbances. Analyzing, predicting, and controlling transient dynamics, which describe transient behaviors of the power system following disturbances, is a major concern in the planning and operation of a power utility. Important conclusions and decisions are made based on the result of system transient behaviors. As today's power network becomes highly interconnected and much more complex, it has become essential to enhance the fundamental understanding of transient dynamics, and to develop fast and reliable computational algorithms. In this thesis, we emphasize mathematical rigor rather than physical insight. Nonlinear dynamical system theory is applied to study two fundamental topics: direct stability assessment and chaotic motions. Conventionally, power system stability is determined by calculating the time-domain transient behaviors for a given disturbance. In contrast, direct methods identify whether or not the system will remain stable once the disturbance is removed by comparing the corresponding energy value of the post-fault system to a calculated threshold value. Direct methods not only avoid the time-consuming numerical integration of the time domain approach, but also provide a quantitative measure of the degree of system stability. We present a general framework for the theoretical foundations of direct methods. Canonical representations of network-reduction models as well as network-preserving models are proposed to facilitate the analysis and the construction of energy functions of various power system models. An advanced and practical method, called the boundary of stability region based controlling unstable equilibrium point method (BCU method), of computing the controlling unstable equilibrium point is proposed along with its theoretical foundation. Numerical solution algorithms capable of supporting on-line applications of direct methods are provided. Further possible improvements and enhancements are

  8. Wind energy program overview

    International Nuclear Information System (INIS)

    1992-02-01

    This overview emphasizes the amount of electric power that could be provided by wind power rather than traditional fossil fuels. New wind power markets, advances in technology, technology transfer, and wind resources are some topics covered in this publication

  9. Model study of the influence of solar wind parameters on electric currents and fields in middle atmosphere at high latitudes

    International Nuclear Information System (INIS)

    Tonev, P.; Velinov, P.

    2012-01-01

    The electric currents and fields in the strato/mesosphere and lower ionosphere are a result mainly of tropospheric electrical generators (thunderstorms and electrified clouds) which principally determine their global distributions and magnitudes. There are, however, additional sources, e.g. the solar wind (SW), whose contribution to these currents and fields is realized by SW-magnetosphere-ionosphere coupling. This last causes creation of large trans-polar electric potential difference VPC in each polar cap of ∼ 30–140 kV and of horizontal scale ∼ 3000 km which is realized through field-aligned currents (FAC) and is controlled by SW parameters. The potential difference VPC forces formation of closure currents in the dynamo-region. Our study by simulation shows that much smaller currents penetrate into the lower atmospheric regions and influence characteristics of the global atmospheric electrical circuit (GEC). Also, the downward mapping of the horizontal electric fields due to the potential difference VPC leads to creation of very small, but non-negligible vertical electric fields at sea level. They have been demonstrated experimentally as significant (up to few tens of per cent) SW-controlled modifications of the GEC electric characteristics at the ground, at polar latitudes. Our model, based on simulation of Maxwell’s equations in the region 0–160 km under steady-state conditions show that similar but relatively much larger SW-dominated modifications of GEC characteristics take place in the strato/mesosphere and lower ionosphere at polar and high latitudes

  10. A comparative study on the effects of air gap wind and walking motion on the thermal properties of Arabian Thawbs and Chinese Cheongsams.

    Science.gov (United States)

    Cui, Zhiying; Fan, Jintu; Wu, Yuenshing

    2016-08-01

    This paper reports on an experimental investigation on the effects of air gap, wind and walking motion on the thermal properties of traditional Arabian thawbs and Chinese cheongsams. Total thermal resistance (It) and vapour resistance (Re) were measured using the sweating fabric manikin - 'Walter', and the air gap volumes of the garments were determined by a 3D body scanner. The results showed the relative changes of It and Re of thawbs due to wind and walking motion are greater than those of cheongsams, which provided an explanation of why thawbs are preferred in extremely hot climate. It is further shown that thermal insulation and vapour resistance of thawbs increase with the air gap volume up to about 71,000 cm(3) and then decrease gradually. Thawbs with higher air permeability have significantly lower evaporative resistance particularly under windy conditions demonstrating the advantage of air permeable fabrics in body cooling in hot environments. Practitioner Summary: This paper aims to better understand the thermal insulation and vapour resistance of traditional Arabian thawbs and Chinese cheongsams, and the relationship between the thermal properties and their fit and design. The results of this study provide a scientific basis for designing ethnic clothing used in hot environments.

  11. Use of the renewable wind and photovoltaic sources, for the recharge of a fleet of electric taxis in Havana, Cuba

    International Nuclear Information System (INIS)

    Sánchez Torres, Yamir

    2017-01-01

    Electrification of the transportation sector seems to be one of the alternatives in terms of restriction of pollutant from that sector. However, it is necessary to study the GHG (Green House Gas) emissions from Generation Power Plants (EGPP) because could be more or less the same of that from the vehicles. Furthermore, Centralized GPP supply would result in distribution losses, bigger fuel consumption and more pollution. Thus, EVs development should be considered as a sustainable solution if powered by electricity systems with considerable share of Renewable Energy Sources (RES). In this paper, the study of the recharge of an EV taxi fleet during night, using photovoltaic and wind mills RES in Havana, Cuba, is analyzed. This work is aiming to find a feasible operational synergy between cited intermittent RES electricity generation and EVs taxi fleet recharge. (author)

  12. On the Use of Energy Storage Technologies for Regulation Services in Electric Power Systems with Significant Penetration of Wind Energy

    DEFF Research Database (Denmark)

    Yang, Bo; Makarov, Yuri; Desteese, John

    2008-01-01

    Energy produced by intermittent renewable resources is sharply increasing in the United States. At high penetration levels, volatility of wind power production could cause additional problems for the power system balancing functions such as regulation. This paper reports some partial results...... and frequently changing regulation signal. Several energy storage options have been analyzed based on thirteen selection criteria. The evaluation process resulted in the selection of flywheels, pumped hydro electric power (or conventional hydro electric power) plant and sodium sulfur or nickel cadmium batteries...... of a project work, recently conducted by the Pacific Northwest National Laboratory (PNNL) for Bonneville Power Administration (BPA). The project proposes to mitigate additional intermittency with the help of Wide Area Energy Management System (WAEMS) that would provide a two-way simultaneous regulation service...

  13. The Effect of Additional Mooring Chains on the Motion Performance of a Floating Wind Turbine with a Tension Leg Platform

    Directory of Open Access Journals (Sweden)

    Jinping Ou

    2012-04-01

    Full Text Available In this study, two types of floating offshore wind turbine (FOWT systems were proposed: a traditional tension leg platform (TLP type and a new TLP type with additional mooring chains. They were both based on the National Renewable Energy Laboratory 5 MW offshore wind turbine model. Taking the coupled effect of dynamic response of the top wind turbine, tower support structure and lower mooring system into consideration, not only were the 1/60 scale model tests for the two floating wind turbine systems done in HIT’s wind-wave tunnel according to the typical design conditions in IEC61400-3 code, but also the numerical simulations corresponding to the scaled model tests were performed by advanced numerical tools. As a result, the numerical results displayed good agreement with the test data. Moreover, the additional mooring chains could play an active role in reducing the surge displacement, surge acceleration and typical tension leg force responses of the FOWT system, which is very beneficial for ensuring the good operational performance and the safety of the FOWT system.

  14. Wind-powered asynchronous AC/DC/AC converter system. [for electric power supply regulation

    Science.gov (United States)

    Reitan, D. K.

    1973-01-01

    Two asynchronous ac/dc/ac systems are modelled that utilize wind power to drive a variable or constant hertz alternator. The first system employs a high power 60-hertz inverter tie to the large backup supply of the power company to either supplement them from wind energy, storage, or from a combination of both at a preset desired current; rectifier and inverter are identical and operate in either mode depending on the silicon control rectifier firing angle. The second system employs the same rectification but from a 60-hertz alternator arrangement; it provides mainly dc output, some sinusoidal 60-hertz from the wind bus and some high harmonic content 60-hertz from an 800-watt inverter.

  15. Power quality in electrical networks with aeolian penetration. Case: The Turiguanó wind farm

    International Nuclear Information System (INIS)

    Sierra Gil, Eduardo; Coello Igarza, Daisnel; Pérez Lorenzo, Adonis

    2013-01-01

    In this work the problem of the aeolian generation is described regarding to the quality of the produced energy because the inverters, that distort the fundamental wave of tension and current, has been incorporate like one of the characteristics of the aeolian generation that use turbines of variable speed, together with the exports and imports of reactive power and the consequent decrease of the power factor; for this purpose takes a practical example, with real measures of reactive powers, power factor and harmonics, carried out in the Demonstrative Wind Farm of Turiguanó and others accumulated measures from the records of the technical documentation of the wind farm, exposing a methodology to determine, with the realized measures, the values of reactive powers, power factor and harmonics for each value of load degree of the wind farm and operation of the turbines. (author)

  16. Wind farm control for stabilisation of electrical networks based on passivity

    Science.gov (United States)

    Fernández, R. D.; Mantz, R. J.; Battaiotto, P. E.

    2010-01-01

    This article presents a control strategy for wind farms equipped with doubly fed induction generators (DFIG) operating in a network with a complex load. As is known from vector control theory, DFIG are able to generate active and reactive powers in an independent way. Therefore, taking into account a unitary power factor, a wind farm control law based on the passivity theory is proposed looking for damping frequency oscillations after a network disturbance. Then, different practical considerations allow to simplify the obtained expression in order to achieve a feasible control law. The last one is added to the normal operating power reference of the wind farm established by a Supervisory Control. Finally, some simulations are shown to support the theoretical considerations.

  17. How to improve the design of the electrical system in future wind power plants

    DEFF Research Database (Denmark)

    Arana Aristi, Iván; Holbøll, Joachim; Bak, C. L.

    2009-01-01

    This paper presents three topics which are important for better performance of future wind farms. The topics are investigated in three coordinated Ph.D. projects ongoing at the Technical University of Denmark (DTU), Aalborg University (AAU) and DONG Energy. The objective of all projects is to imp......This paper presents three topics which are important for better performance of future wind farms. The topics are investigated in three coordinated Ph.D. projects ongoing at the Technical University of Denmark (DTU), Aalborg University (AAU) and DONG Energy. The objective of all projects...... and wind farm transformers, and to develop a methodology on how to select appropriate equipment for the power system, control system and protection system....

  18. Dynamic Power Dispatch Considering Electric Vehicles and Wind Power Using Decomposition Based Multi-Objective Evolutionary Algorithm

    Directory of Open Access Journals (Sweden)

    Boyang Qu

    2017-12-01

    Full Text Available The intermittency of wind power and the large-scale integration of electric vehicles (EVs bring new challenges to the reliability and economy of power system dispatching. In this paper, a novel multi-objective dynamic economic emission dispatch (DEED model is proposed considering the EVs and uncertainties of wind power. The total fuel cost and pollutant emission are considered as the optimization objectives, and the vehicle to grid (V2G power and the conventional generator output power are set as the decision variables. The stochastic wind power is derived by Weibull probability distribution function. Under the premise of meeting the system energy and user’s travel demand, the charging and discharging behavior of the EVs are dynamically managed. Moreover, we propose a two-step dynamic constraint processing strategy for decision variables based on penalty function, and, on this basis, the Multi-Objective Evolutionary Algorithm Based on Decomposition (MOEA/D algorithm is improved. The proposed model and approach are verified by the 10-generator system. The results demonstrate that the proposed DEED model and the improved MOEA/D algorithm are effective and reasonable.

  19. Solar wind energy and electric field transfer to the Earth's magnetosphere VIA magnetopause reconnection

    International Nuclear Information System (INIS)

    Gonzalez, W.D.; Gonzalez, A.L.C.

    1981-01-01

    Some general expressions for the convection and parallel electric fields as well as for the energy transfer, due to magnetopause reconnection, are derived using a nose-reconnection model that takes into account the presence of the clefts. For the case of equal geomagnetic and magnetosheath field amplitudes, the expression for the power dissipated by the convection electric field reduces to the substorm parameter e widely discussed in the recent literature. This result suggests that magnetopause reconnection is defined at the nose with a tilted reconnection line, but that the convection electric field is related only to the dawn-dusk component of the reconnection electric field, as defined at high latitudes

  20. On Electrical Design and Technical Performance Requirements for Large Scale Wind Farms

    DEFF Research Database (Denmark)

    Gordon, Mark; Keerthipala, W.; Fernando, A.

    2009-01-01

    plant operating limits for ensuring power system security at the high voltage point of connection. Experiences presented here refer mainly to few of the selected technical requirements and issues encountered during the process of wind farms connections into Eastern Australian power system. In particular......This paper presents and discusses technical performance requirements for connection of large scale wind turbine generating systems into HV transmission networks. Requirements have been presented for the purpose of achieving performance enhanced operation, reliability and assessment of the power...

  1. Practical methodologies for the calculation of capacity in electricity markets for wind energy

    International Nuclear Information System (INIS)

    Botero B, Sergio; Giraldo V, Luis Alfonso; Isaza C, Felipe

    2008-01-01

    Determining the real capacity of the generators in a power market is an essential task in order to estimate the actual system reliability, and to estimate the reward for generators due to their capacity in the firm energy market. In the wind power case, which is an intermittent resource, several methodologies have been proposed to estimate the capacity of a wind power emplacement, not only for planning but also for firm energy remuneration purposes. This paper presents some methodologies that have been proposed or implemented around the world in order to calculate the capacity of this energy resource.

  2. The history of re-connection and the concept of the solar wind plasma with relatively small electrical conductivity

    Science.gov (United States)

    Chertkov, A. D.

    1995-01-01

    Petschek's 're-connection' model, aspiring to be universal, treated as a boundary problem meets unresolvable difficulties connected with impossibility to specify correctly boundary and initial conditions. This problem was incorrectly formulated. Hence, ineradicable logarithmic singularities occurred on the boundary surfaces. Attempts to eliminate them by incorporating the finite electrical conductivity are incorrect. This should lead to the change in the equation type, boundary condition type and in consequence to the change in solutions. Besides, the slow mode shocks cannot be driven by small internal source. As an alternative a new plasma concept is suggested. The state of fully ionized plasma in space depends completely on the entropy of the plasma heating source and on the process in which plasma is involved. The presumptive source of the solar wind creation - the induction electric field of the solar origin - has very low entropy. The state of plasma should be very far from the thermodynamic equilibrium. Debye's screening is not complete. The excitation of the powerful resonant self-consistent electric fields in plasma provides low electric conductivity. The MHD problems should be treated in frameworks of dissipative theories.

  3. Impact of plug-in hybrid electric vehicles on power systems with demand response and wind power

    International Nuclear Information System (INIS)

    Wang Jianhui; Liu Cong; Ton, Dan; Zhou Yan; Kim, Jinho; Vyas, Anantray

    2011-01-01

    This paper uses a new unit commitment model which can simulate the interactions among plug-in hybrid electric vehicles (PHEVs), wind power, and demand response (DR). Four PHEV charging scenarios are simulated for the Illinois power system: (1) unconstrained charging, (2) 3-hour delayed constrained charging, (3) smart charging, and (4) smart charging with DR. The PHEV charging is assumed to be optimally controlled by the system operator in the latter two scenarios, along with load shifting and shaving enabled by DR programs. The simulation results show that optimally dispatching the PHEV charging load can significantly reduce the total operating cost of the system. With DR programs in place, the operating cost can be further reduced. - Research highlights: → A unit commitment model is used to simulate the interactions among plug-in hybrid electric vehicles (PHEVs), wind power, and demand response (DR). → Different PHEV charging scenarios are simulated on the Illinois power system → Load shifting and shaving enabled by DR programs are also modeled. → The simulation results show that the operating cost can be reduced with DR and optimal PHEV charging.

  4. A STRATEGY TO IMPROVE THE QUALITY OF THE ELECTRIC POWER PRODUCED BY A WIND TURBINE UNDER VARIABLE SPEED USING A PROPORTIONAL RESONANT CONTROLLER

    Directory of Open Access Journals (Sweden)

    F. D. Menga

    2016-05-01

    Full Text Available The wind power is well adapted nowadays as solution to the production of electricity or for mechanical use. But wind is a very fluctuating source of energy; it generates a non-permanent and variable power to the loads. This paper presents a strategy to improve the quality of the electric power produced by a wind turbine under variable speed. The mathematical modeling of the various elements of the conversion system is performed. Two control strategies are developed to improve the quality of the energy produced by the wind turbine. The first consists to a judicious management of the DC bus and the second to control the inverters with a corrective proportional resonant. The results obtained after implementation and simulation under Matlab/Simulink platform are presented.

  5. Dark green electricity comes from the sea: Capitalizing on ecological merits of offshore wind power?

    NARCIS (Netherlands)

    Toonen, H.M.; Lindeboom, H.J.

    2015-01-01

    European consumers are willing to pay more for “green” electricity, as they highly value renewable energy sources for the contribution to combating climate change. There is a push for getting higher levels of sustainability, leading to a differentiation of Europe‘s electricity market. In this

  6. Excessive price reduction and extreme volatility in wind dominant electricity markets; solutions and emerging challenges

    DEFF Research Database (Denmark)

    Farashbashi-Astaneh, Seyed-Mostafa; Chen, Zhe; Mousavi, Omid Alizadeh

    2013-01-01

    markets. While high price volatility imposes elevated risk levels for both electricity suppliers and consumers, excessive price reduction of electricity is a disincentive for investment in new generation capacity and might jeopardizes system adequacy in long term. A comparative study between marginal...

  7. Electric vehicle battery charging algorithm using PMSM windings and an inverter as an active rectifier

    DEFF Research Database (Denmark)

    Zaja, Mario; Oprea, Matei-lon; Suárez, Carlos Gómez

    2014-01-01

    A major setback for large scale electric vehicle market expansion compared to their internal combustion competitors consists in their high price and low driving range. One way of reducing the cost, dimensions and mass of electric vehicles is to eliminate the dedicated AC/DC converter used...

  8. Direct load control for electricity supply and demand matching : increasing reliability of wind energy

    NARCIS (Netherlands)

    Hoeve ten, Marieke

    2009-01-01

    In Sweden as well as in The Netherlands energy policy is increasingly aiming at extending the use of renew-able sources. In accordance with the targets of the European Union, both countries have formulated national targets for the year 2020. For wind ener

  9. The potential for wind energy meeting electricity needs on Vancouver Island

    NARCIS (Netherlands)

    Prescott, R.; Kooten, van G.C.; Zhu, H.

    2007-01-01

    In this paper, an in-depth analysis of power supply and demand on Vancouver Island is used to provide information about the optimal allocation of power across 'generating' sources and to investigate the economics of wind generation and penetrability into the Island grid. The methodology developed

  10. InfraSound from wind turbines : observations from Castle River wind farm. Volume 1

    International Nuclear Information System (INIS)

    Edworthy, J.; Hepburn, H.

    2005-01-01

    Although infrasound has been discussed as a concern by groups opposed to wind farm facilities, there is very little information available about infrasound and wind turbines. This paper presented details of a project conducted by VisionQuest, the largest wind power producer in Canada. Three sensor types were used: precision sound analyzer, seismic geophones, and calibrated microphones to take measurements in low, medium and high winds. The project also measured infrasound when the wind farm was not operating. Acquisition geometry was presented, as well as details of apparent attenuations of wind noise. It was noted that high wind noise was a dominant factor and that there was little difference when the wind farm was not operational. It was suggested that turbines have no impact with high wind, since wind noise is not attenuated with distance. It was noted that increased geophone amplitudes indicate high wind coupled motion which is attenuated when the turbines are on. Results indicate that all frequencies showed attenuation with distance. Evidence showed that low frequency sound pressure levels were often lower when the turbines were switched on. Where turbines contributed to sound pressure levels, the magnitude of the contribution was below levels of concern to human health. Ambient sound pressure levels were much higher than contributions from wind turbines. It was concluded that wind itself generates infrasound. Wind turbines generate low levels of infrasound, detectable very close to facilities at low to medium wind speeds. Wind turbines may reduce ambient infrasound levels at high wind speeds by converting the energy from the wind into electricity. refs., tabs., figs

  11. Taming hurricanes with arrays of offshore wind turbines that simultaneously reduce global warming and air pollution and provide normal electric power (Invited)

    Science.gov (United States)

    Jacobson, M. Z.; Archer, C. L.; Kempton, W.

    2013-12-01

    Hurricanes cause catastrophic damage to many coastal regions worldwide. This paper examines whether large arrays of offshore wind turbines, used to generate electricity and replace fossil fuels during most of the year, can also tame the destructive power of a hurricane. Results suggest that large turbine arrays may diminish peak near-surface hurricane wind speeds by up to 25-39 m/s (56-88 mph) and storm surge by 12-72%. Benefits occur whether turbine arrays are located immediately upstream of a city or along an expanse of coastline. The reduction in wind speed due to large arrays increases the probability of survival of even currently designed turbines. The net cost of turbine arrays (cost of capital plus operation less cost reduction from electricity generation and from health, climate, and hurricane avoidance) is estimated to be less than today's fossil-fuel electricity generation cost in these regions.

  12. Myocardial metabolism, perfusion, wall motion and electrical activity in Duchenne muscular dystrophy

    International Nuclear Information System (INIS)

    Perloff, J.K.; Henze, E.; Schelbert, H.R.

    1982-01-01

    The cardiomyopathy of Duchenne's muscular dystrophy originates in the posterobasal left ventricle and extends chiefly to the contiguous lateral wall. Ultrastructural abnormalities in these regions precede connective tissue replacement. We postulated that a metabolic fault coincided with or antedated the subcellular abnormality. Accordingly, regional left ventricular metabolism, perfusion and wall motion were studied using positron computed tomography and metabolic isotopes supplemented by thallium perfusion scans, equilibrium radionuclide angiography and M-mode and two-dimensional echocardiography. To complete the assessment, electrocardiograms, vectorcardiograms, 24 hour taped electrocardiograms and chest x-rays were analyzed. Positron computed tomography utilizing F-18 2-fluoro 2-deoxyglucose (FDG) provided the first conclusive evidence supporting the hypothesis of a premorphologic regional metabolic fault. Thus, cardiac involvement in duchenne dystrophy emerges as a unique form of heart disease, genetically targeting specific regions of ventricular myocardium for initial metabolic and subcellular changes. Reported ultrastructural abnormalities of the impulse and conduction systems provide, at least in part, a basis for the clinically observed sinus node, intraatrial, internodal, AV nodal and infranodal disorders

  13. Prospecting for Wind

    Science.gov (United States)

    Swapp, Andy; Schreuders, Paul; Reeve, Edward

    2011-01-01

    Many people use wind to help meet their needs. Over the years, people have been able to harness or capture the wind in many different ways. More recently, people have seen the rebirth of electricity-generating wind turbines. Thus, the age-old argument about technology being either good or bad can also be applied to the wind. The wind can be a…

  14. Determination of wind energy potential and its implementation concept for the electricity market in the Vojvodina region (north Serbia: An overview

    Directory of Open Access Journals (Sweden)

    Micić Tanja

    2014-01-01

    Full Text Available Renewable energy sources play an important role in the future not only for the European countries, but for many countries worldwide. Most cost-effective and reliable large wind energy conversion systems are becoming the main focus of wind energy research and technology development, all in order to make wind energy competitive with other more traditional sources of electrical energy like coal, gas and nuclear generation. Serbia, along with neighboring countries, has a high potential for developing energy production from renewable energy sources. Wind energy in Serbia, despite its great potential, is only partly studied and insufficiently used. This study aims to provide summary of wind energy potentials in the region of Vojvodina, which is an important economic region in northern Serbia. Its existing electrical energy status is thoroughly investigated according to the recent developments of wind energy production on global, regional and local scale. The main purpose of this study is the implementation of energy efficiency concept with purpose of satisfying the needs of Serbian electricity market.

  15. The most intense electric currents in turbulent high speed solar wind

    Science.gov (United States)

    Podesta, J. J.

    2017-12-01

    Theory and simulations suggest that dissipation of turbulent energy in collisionless astrophysical plasmas occurs most rapidly in spatial regions where the current density is most intense. To advance understanding of plasma heating by turbulent dissipation in the solar corona and solar wind, it is of interest to characterize the properties of plasma regions where the current density takes exceptionally large values and to identify the operative dissipation processes. In the solar wind, the curl of the magnetic field cannot be measured using data from a single spacecraft, however, a suitable proxy for this quantity can be constructed from the spatial derivative of the magnetic field along the flow direction of the plasma. This new approach is used to study the properties of the most intense current carrying structures in a high speed solar wind stream near 1 AU. In this study, based on 11 Hz magnetometer data from the WIND spacecraft, the spatial resolution of the proxy technique is approximately equal to the proton inertial length. Intense current sheets or current carrying structures were identified as events where the magnitude of the current density exceeds μ+5σ, where μ and σ are the mean and standard deviation of the magnitude of the current density (or its proxy), respectively. Statistical studies show (1) the average size of these 5σ events is close to the smallest resolvable scale in the data set, the proton inertial length; (2) the linear distance between neighboring events follows a power law distribution; and (3) the average peak current density of 5σ events is around 1 pA/cm2. The analysis techniques used in these studies have been validated using simulated spacecraft data from three dimensional hybrid simulations which show that results based on the analysis of the proxy are qualitatively and quantitatively similar to results based on the analysis of the true current density.

  16. From LCAs to simplified models: a generic methodology applied to wind power electricity.

    Science.gov (United States)

    Padey, Pierryves; Girard, Robin; le Boulch, Denis; Blanc, Isabelle

    2013-02-05

    This study presents a generic methodology to produce simplified models able to provide a comprehensive life cycle impact assessment of energy pathways. The methodology relies on the application of global sensitivity analysis to identify key parameters explaining the impact variability of systems over their life cycle. Simplified models are built upon the identification of such key parameters. The methodology is applied to one energy pathway: onshore wind turbines of medium size considering a large sample of possible configurations representative of European conditions. Among several technological, geographical, and methodological parameters, we identified the turbine load factor and the wind turbine lifetime as the most influent parameters. Greenhouse Gas (GHG) performances have been plotted as a function of these key parameters identified. Using these curves, GHG performances of a specific wind turbine can be estimated, thus avoiding the undertaking of an extensive Life Cycle Assessment (LCA). This methodology should be useful for decisions makers, providing them a robust but simple support tool for assessing the environmental performance of energy systems.

  17. More homogeneous wind conditions under strong climate change decrease the potential for inter-state balancing of electricity in Europe

    Directory of Open Access Journals (Sweden)

    J. Wohland

    2017-11-01

    Full Text Available Limiting anthropogenic climate change requires the fast decarbonization of the electricity system. Renewable electricity generation is determined by the weather and is hence subject to climate change. We simulate the operation of a coarse-scale fully renewable European electricity system based on downscaled high-resolution climate data from EURO-CORDEX. Following a high-emission pathway (RCP8.5, we find a robust but modest increase (up to 7 % of backup energy in Europe through the end of the 21st century. The absolute increase in the backup energy is almost independent of potential grid expansion, leading to the paradoxical effect that relative impacts of climate change increase in a highly interconnected European system. The increase is rooted in more homogeneous wind conditions over Europe resulting in intensified simultaneous generation shortfalls. Individual country contributions to European generation shortfall increase by up to 9 TWh yr−1, reflecting an increase of up to 4 %. Our results are strengthened by comparison with a large CMIP5 ensemble using an approach based on circulation weather types.

  18. More homogeneous wind conditions under strong climate change decrease the potential for inter-state balancing of electricity in Europe

    Science.gov (United States)

    Wohland, Jan; Reyers, Mark; Weber, Juliane; Witthaut, Dirk

    2017-11-01

    Limiting anthropogenic climate change requires the fast decarbonization of the electricity system. Renewable electricity generation is determined by the weather and is hence subject to climate change. We simulate the operation of a coarse-scale fully renewable European electricity system based on downscaled high-resolution climate data from EURO-CORDEX. Following a high-emission pathway (RCP8.5), we find a robust but modest increase (up to 7 %) of backup energy in Europe through the end of the 21st century. The absolute increase in the backup energy is almost independent of potential grid expansion, leading to the paradoxical effect that relative impacts of climate change increase in a highly interconnected European system. The increase is rooted in more homogeneous wind conditions over Europe resulting in intensified simultaneous generation shortfalls. Individual country contributions to European generation shortfall increase by up to 9 TWh yr-1, reflecting an increase of up to 4 %. Our results are strengthened by comparison with a large CMIP5 ensemble using an approach based on circulation weather types.

  19. Blown by the wind. Replacing nuclear power in German electricity generation

    International Nuclear Information System (INIS)

    Lechtenböhmer, Stefan; Samadi, Sascha

    2013-01-01

    Only three days after the beginning of the nuclear catastrophe in Fukushima, Japan, on 11 March 2011, the German government ordered 8 of the country's 17 existing nuclear power plants (NPPs) to stop operating within a few days. In summer 2011 the government put forward a law – passed in parliament by a large majority – that calls for a complete nuclear phase-out by the end of 2022. These government actions were in contrast to its initial plans, laid out in fall 2010, to expand the lifetimes of the country's NPPs. The immediate closure of 8 NPPs and the plans for a complete nuclear phase-out within little more than a decade, raised concerns about Germany's ability to secure a stable supply of electricity. Some observers feared power supply shortages, increasing CO 2 -emissions and a need for Germany to become a net importer of electricity. Now – a little more than a year after the phase-out law entered into force – this paper examines these concerns using (a) recent statistical data on electricity production and demand in the first 15 months after the German government's immediate reaction to the Fukushima accident and (b) reviews the most recent projections and scenarios by different stakeholders on how the German electricity system may develop until 2025, when NPPs will no longer be in operation. The paper finds that Germany has a realistic chance of fully replacing nuclear power with additional renewable electricity generation on an annual basis by 2025 or earlier, provided that several related challenges, e.g. expansion of the grids and provision of balancing power, can be solved successfully. Already in 2012 additional electricity generation from renewable energy sources in combination with a reduced domestic demand for electricity will likely fully compensate for the reduced power generation from the NPPs shut down in March 2011. If current political targets will be realised, Germany neither has to become a net electricity importer, nor will be unable

  20. Marangoni Effect-Driven Motion of Miniature Robots and Generation of Electricity on Water.

    Science.gov (United States)

    Zhang, Lidong; Yuan, Yihui; Qiu, Xiaxin; Zhang, Ting; Chen, Qing; Huang, Xinhua

    2017-11-07

    The well-known Marangoni effect perfectly supports the dynamic mechanism of organic solvent-swollen gels on water. On this basis, we report a series of energy conversion processes of concentrated droplets of polyvinylidene fluoride/dimethyl formamide (PVDF/DMF) that can transfer chemical-free energy to kinetic energy to rapidly rotate itself on water. This droplet (22.2 mg) is capable to offer kinetic energy of 0.099 μJ to propel an artificial paper rocket of 31.8 mg to move over 560 cm on water at an initial velocity of 7.9 cm s -1 . As the droplet increases to 35.0 mg, a paper goldfish of 10.6 mg can be driven to swim longer at a higher initial velocity of 20 cm s -1 . The kinetic energy of the droplet can be further converted to electrical energy through an electromagnetic generator, in which as a 0.5 MΩ resistor is loaded, the peak output reaches 6.5 mV that corresponds to the power density of 0.293 μW kg -1 . We believe that this report would open up a promising avenue to exploit energies for applications in miniature robotics.

  1. Emissions from cycling of thermal power plants in electricity systems with high penetration of wind power: Life cycle assessment for Ireland

    DEFF Research Database (Denmark)

    Turconi, Roberto; O'Dwyer, C.; Flynn, D.

    2014-01-01

    , as part of LCA of electricity generation, the efficiency reduction would result in large underestimation of emissions, e.g. up to 65% for an oil power plant. Overall, cycling emissions accounted for less than 7% of lifecycle CO2, NOx and SO2 emissions in the five scenarios considered: while......-load electricity production shifts to a cleaner source than coal. Finally, the present study indicates that, in terms of emission reductions, the priority for Ireland is to phase out coal-based power plants. While investing in new storage capacity reduces system operating costs at high wind penetrations and limits......The increase of renewable sources in the power sector is an important step towards more sustainable electricity production. However, introducing high shares of variable renewables, such as wind and solar, cause dispatchable power plants to vary their output to fulfill the remaining electrical...

  2. Model-Based Control of a Ballast-Stabilized Floating Wind Turbine Exposed to Wind and Waves

    DEFF Research Database (Denmark)

    Christiansen, Søren

    2013-01-01

    wind turbine, for water depths beyond 50 meters where winds are stronger and less turbulent. A floating wind turbine is subject to not only aerodynamics and wind induced loads, but also to hy-drodynamics and wave induced loads. In contrast to a bottom fixed wind turbine, the floating structure....... A time varying control model is presented based on the wind speed and wave frequency. Estimates of the wind speed and wave frequency are used as scheduling variables in a gain scheduled linear quadratic controller to improve the electrical power production while reducing fatigue. To address the problem...... of negative damped fore--aft tower motion, addi-tional control loops are suggested which stabilize the response of the onshore controller and reduce the impact of the wave induced loads. This research is then extended to model predictive control, to further address wave disturbances. In the context of control...

  3. The value of electric energy storage in electricity systems with high shares of wind and solar PV: the case of France in the energy transition

    International Nuclear Information System (INIS)

    Villavicencio, Manuel

    2017-01-01

    The adoption of ambitious targets for variable renewable energies (VRE) such as wind and solar has important effects on the technical and economic operation of power systems. Increasing shares of VRE will in particular require the deployment of more flexible and responsive technologies. Key flexibility providers in the scope are demand side management (DSM) and different forms of electric energy storage (EES) such as pumped hydroelectric (PHS), Li-ion batteries (Li-ion), and compressed air (CAES), among others. It have been previously showed how the value and the deployment of such new flexibility providers depended on the shares of VRE shares introduced into the system (Brijs et al., 2016; Van Stiphout et al., 2015; Villavicencio, 2017). Building on this works, this paper explores the value of storage in the context of a realistic Brownfield model calibrated on the existing French electricity system. In particular, this paper compares the value of storage (a) in a system corresponding to the target of 27% VRE production formulated by the French government in its 2015 Energy Transition Act by 2020 and (b) in a system corresponding to the target of 40% VRE production formulated in the same Act by 2030. The latter case will necessarily reflect the additional target which by 2025 limits the share of nuclear power to 50% of electricity production. In 2020, 4.7 GW of DSM are sufficient to provide the required flexibility and no EES investments will be needed. By 2030, however, in addition to a comparable level of DSM, 3.2 GW of additional EES investments are required. These storage solutions will generate an economic value of euro 350 million per year and will increases overall welfare by euro 670 million per year by 2030. The modeling yields a number of additional policy relevant results. First, limiting nuclear production will open opportunities for alternative base and mid-load providers, mainly gas, implying a threefold increase of CO 2 emissions compared to 2020

  4. On the local time dependence of the penetration of solar wind-induced electric fields to the magnetic equator

    Directory of Open Access Journals (Sweden)

    M. C. Kelley

    2009-08-01

    Full Text Available For a period of a few hours, the penetration of electric fields of solar wind origin is at its highest efficiency. In November 2003, five days of continuous vertical drift data were obtained at the Jicamarca Radio Observatory. Here we have isolated a range of frequencies centered at a few-hour period for a five-day period and have explored the local time dependence of the penetration, along with the time delay due to magnetospheric effects. We find that the latter ranges from 15 to 25 min. For the local time dependence, we find that the period of anti-correlation is roughly from 21:00 to 04:00 LT, with positive correlation at other local times.

  5. An Examination of AC/HVDC Power Circuits for Interconnecting Bulk Wind Generation with the Electric Grid

    Directory of Open Access Journals (Sweden)

    Daniel Ludois

    2010-06-01

    Full Text Available The application of high voltage dc (HVDC transmission for integrating large scale and/or off-shore wind generation systems with the electric grid is attractive in comparison to extra high voltage (EHV ac transmission due to a variety of reasons. While the technology of classical current sourced converters (CSC using thyristors is well established for realization of large HVDC systems, the technology of voltage sourced converters (VSC is emerging to be an alternative approach, particularly suitable for multi-terminal interconnections. More recently, a more modular scheme that may be termed ‘bridge of bridge’ converters (BoBC has been introduced to realize HVDC systems. While all these three approaches are functionally capable of realizing HVDC systems, the converter power circuit design trade-offs between these alternatives are not readily apparent. This paper presents an examination of these topologies from the point of view of power semiconductor requirements, reactive component requirements, operating losses, fault tolerance, multi-terminal operation, modularity, complexity, etc. Detailed analytical models will be used along with a benchmark application to develop a comparative evaluation of the alternatives that maybe used by wind energy/bulk transmission developers for performing engineering trade-off studies.

  6. Overview of condition monitoring and operation control of electric power conversion systems in direct-drive wind turbines under faults

    Science.gov (United States)

    Huang, Shoudao; Wu, Xuan; Liu, Xiao; Gao, Jian; He, Yunze

    2017-09-01

    Electric power conversion system (EPCS), which consists of a generator and power converter, is one of the most important subsystems in a direct-drive wind turbine (DD-WT). However, this component accounts for the most failures (approximately 60% of the total number) in the entire DD-WT system according to statistical data. To improve the reliability of EPCSs and reduce the operation and maintenance cost of DD-WTs, numerous researchers have studied condition monitoring (CM) and fault diagnostics (FD). Numerous CM and FD techniques, which have respective advantages and disadvantages, have emerged. This paper provides an overview of the CM, FD, and operation control of EPCSs in DD-WTs under faults. After introducing the functional principle and structure of EPCS, this survey discusses the common failures in wind generators and power converters; briefly reviewed CM and FD methods and operation control of these generators and power converters under faults; and discussed the grid voltage faults related to EPCSs in DD-WTs. These theories and their related technical concepts are systematically discussed. Finally, predicted development trends are presented. The paper provides a valuable reference for developing service quality evaluation methods and fault operation control systems to achieve high-performance and high-intelligence DD-WTs.

  7. Optimal bidding in Turkey day ahead electricity market for wind energy and pumped storage hydro power plant

    Directory of Open Access Journals (Sweden)

    Ceyhun Yıldız

    2016-10-01

    Full Text Available In electrical grid; when the demand power increases energy prices increase, when the demand decreases energy prices decrease. For this reason; to increase the total daily income, it is required to shift generations to the hours that high demand power values occurred. Wind Power Plants (WPP have unstable and uncontrollable generation characteristic. For this reason, energy storage systems are needed to shift the generations of WPPs in time scale. In this study, four wind power plants (WPP which are tied to the Turkish interconnected grid and a pumped hydro storage power plant (PSPP that meets the energy storage requirement of these power plants are investigated in Turkey day ahead energy market. An optimization algorithm is developed using linear programming technique to maximize the day ahead market bids of these plants which are going to generate power together. When incomes and generations of the plants that are operated with optimization strategy is analyzed, it is seen that annual income increased by 2.737% compared with WPPs ‘s alone operation and generations are substantially shifted to the high demand power occurred hours.

  8. Electricity. EDF and Alstom hailed world champions of offshore wind energy

    International Nuclear Information System (INIS)

    Dupin, Ludovic

    2012-01-01

    This article comments the results of recent invitation to tender for several offshore wind farms in France. Three sites were attributed to the Eolien Maritime France consortium (EDF, Dong Energy and Alstom), one to Ailes Maritimes (Iberdrola, Eole-Res and Areva). Huge investments, thousands of jobs and the construction of new factories are at stake. Areva and even more GDF Suez, the main looser of this tender process, feel that the choice has been made in favour of EDF. As these projects are still to be confirmed, others are foreseen to reach an offshore production of 6000 MW. French actors will also have to conquer foreign markets, notably in Great-Britain

  9. Decision Support Tools for Electricity Retailers, Wind Power and CHP Plants Using Probabilistic Forecasts

    DEFF Research Database (Denmark)

    Zugno, Marco; Morales González, Juan Miguel; Madsen, Henrik

    2015-01-01

    This paper reviews a number of applications of optimization under uncertainty in energy markets resulting from the research project ENSYMORA. A general mathematical formulation applicable to problems of optimization under uncertainty in energy markets is presented. This formulation can......: trading for a price-maker wind power producer, management of heat and power systems, operation for retailers in a dynamic-price market. A selection of results shows the viability and appropriateness of the presented stochastic optimization approaches for managing energy systems under uncertainty....

  10. The merit order effect of wind and photovoltaic electricity generation in Germany 2008–2016: Estimation and distributional implications

    International Nuclear Information System (INIS)

    Cludius, Johanna; Hermann, Hauke; Matthes, Felix Chr.; Graichen, Verena

    2014-01-01

    Generation from renewable energy sources in Germany has experienced a considerable uptake in recent years. Mainly responsible for this development is the German Renewable Energy Sources Act (Erneuerbare Energien Gesetz, EEG). This paper considers redistributive implications of the EEG for different electricity consumers. Using time-series regression analysis, we show that electricity generation by wind and PV has reduced spot market prices considerably by 6 €/MWh in 2010 rising to 10 €/MWh in 2012. We use these results to build a near-term forecasting tool for merit order effects, projected to reach 14-16 €/MWh in 2016. On the other hand, the costs of the EEG are passed forward to consumers in the form of a surcharge. Our findings highlight significant redistributive transfers under the current design of the EEG. In particular, some energy-intensive industries are benefiting from lower wholesale electricity prices whilst being largely exempted from contributing to the costs of the scheme. We also highlight implications of our results for other areas for reform of the EEG, such as adequate remuneration mechanisms that ensure efficient operation and investment decisions are made under the scheme. More generally, these findings suggest that policy makers need to integrate distributional assessments into policy design and implementation. - Highlights: • The German Renewable Energy Sources Act (EEG) has important distributional impacts on different electricity consumers. • Likely wealth transfers from households and small business to energy-intensive industry. • Merit order effects of around 10 €/MWh in 2012 are set to rise to 14–16 €/MWh in 2016. • These effects likely overcompensate exempt industry for contribution to cost of the EEG. • Implications for short- and long-term reform of the EEG and the design of renewable energy policy in general

  11. Wind energy technical-economic viability under the new regulatory rules of the Brazilian electric sector; Viabilidade tecnico-economica da energia eolica face ao novo marco regulatorio do setor eletrico brasileiro

    Energy Technology Data Exchange (ETDEWEB)

    Dutra, Ricardo Marques

    2001-02-15

    The wind energy development in the world shows as one of the most important and promising technologies in the clean energy generation complement. This work presents the wind energy evolution and utilization in the electric power generation, the environmental impacts and perspectives. Considering the great wind potential in Brazil and the new rules of the electric sector, technical feasibility studies were developed based on regions north and northeast wind data as well as economic feasibility studies based on the new regulatory rules for the energy renewable sources. The results show that is possible to generate clean energy within the new context of the electricity sector.(author)

  12. Utilization of surplus electricity from wind power for dynamic biogas upgrading

    DEFF Research Database (Denmark)

    Jurgensen, Lars; Ehimen, Ehiazesebhor Augustine; Born, Jens

    2014-01-01

    The methanation of CO2 has been increasingly discussed for the potential long term storage of electricity and for facilitating grid load management. Using the regions of northern Germany as a case study, the feasibility of CO2 conversion from biogas plants and its integration in existing natural ...... that with 480 biogas plants in the region would be able to utilize up to 0.7 TWh surplus electricity could be used to produce 100 106 m3 at standard temperature and pressure of upgraded methane per year.......The methanation of CO2 has been increasingly discussed for the potential long term storage of electricity and for facilitating grid load management. Using the regions of northern Germany as a case study, the feasibility of CO2 conversion from biogas plants and its integration in existing natural...... gas grid was examined in this study. Furthermore the material and energy flows of in the methanation process, were evaluated to provide expression for the quantities of excess electrical energy which could be potentially stored using the biogas integrated systems. The study results showed...

  13. Real-Time Tariffs for Electric Vehicles in Wind Power based Power Systems

    DEFF Research Database (Denmark)

    Morais, Hugo; Sousa, Tiago; Silva, Marco

    2013-01-01

    The use of Electric Vehicles (EVs) will change significantly the planning and management of power systems in a near future. This paper proposes a real-time tariff strategy for the charge process of the EVs. The main objective is to evaluate the influence of real-time tariffs in the EVs owners...

  14. 75 FR 61414 - Basin Electric Power Cooperative: South Dakota PrairieWinds Project

    Science.gov (United States)

    2010-10-05

    ... renewable energy goals. The resources or environmental factors that could be affected by the proposed... purpose and need, Basin Electric identified construction of the proposed Project as its best course of... environmental factors (e.g., soils, topography and geology, water resources, air quality, biological resources...

  15. Research on Control Strategies of an Open-End Winding Permanent Magnet Synchronous Driving Motor (OW-PMSM-Equipped Dual Inverter with a Switchable Winding Mode for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Liang Chu

    2017-05-01

    Full Text Available An open-end winding permanent magnet synchronous motor (PMSM has a larger range of speed regulation than normal PMSM with the same DC voltage, and the control method is more flexible. It can also manage energy distribution between two power sources without a DC/DC converter. This paper aims at an electric vehicle equipped with OW-PMSM drive system with dual power sources and dual inverters; based on analyzing the external characteristics of each winding mode, we propose a winding mode switching strategy whose torque saturation judgmental algorithm, which is insensitive to motor’s parameters, could automatically realize upswitching of the winding mode. The proposed multi-level current hysteresis modulation algorithm could set the major power source and switch it at any time in independent mode, which accomplishes energy distribution between two power sources; its two control methods, low switching frequency method and high power difference method, could achieve different energy distribution effects. Simulation results confirm the validity and effectiveness of the winding mode switching strategy and current modulation method. They also show that an electric vehicle under the proposed control methods has better efficiency than one equipped with a traditional OW-PMSM drive system under traditional control.

  16. Low Wind Speed Turbine Project Phase II: The Application of Medium-Voltage Electrical Apparatus to the Class of Variable Speed Multi-Megawatt Low Wind Speed Turbines; 15 June 2004--30 April 2005

    Energy Technology Data Exchange (ETDEWEB)

    Erdman, W.; Behnke, M.

    2005-11-01

    Kilowatt ratings of modern wind turbines have progressed rapidly from 50 kW to 1,800 kW over the past 25 years, with 3.0- to 7.5-MW turbines expected in the next 5 years. The premise of this study is simple: The rapid growth of wind turbine power ratings and the corresponding growth in turbine electrical generation systems and associated controls are quickly making low-voltage (LV) electrical design approaches cost-ineffective. This report provides design detail and compares the cost of energy (COE) between commercial LV-class wind power machines and emerging medium-voltage (MV)-class multi-megawatt wind technology. The key finding is that a 2.5% reduction in the COE can be achieved by moving from LV to MV systems. This is a conservative estimate, with a 3% to 3.5% reduction believed to be attainable once purchase orders to support a 250-turbine/year production level are placed. This evaluation considers capital costs as well as installation, maintenance, and training requirements for wind turbine maintenance personnel. Subsystems investigated include the generator, pendant cables, variable-speed converter, and padmount transformer with switchgear. Both current-source and voltage-source converter/inverter MV topologies are compared against their low-voltage, voltage-source counterparts at the 3.0-, 5.0-, and 7.5-MW levels.

  17. Decision Support Tools for Electricity Retailers, Wind Power and CHP Plants Using Probabilistic Forecasts

    Directory of Open Access Journals (Sweden)

    Marco Zugno

    2015-06-01

    Full Text Available This paper reviews a number of applications of optimization under uncertainty in energy markets resulting from the research project ENSYMORA. A general mathematical formulation applicable to problems of optimization under uncertainty in energy markets is presented. This formulation can be effortlessly adapted to describe different approaches: the deterministic one (usable within a rolling horizon scheme, stochastic programming and robust optimization. The different features of this mathematical formulation are duly interpreted with a view to the energy applications reviewed in this paper: trading for a price-maker wind power producer, management of heat and power systems, operation for retailers in a dynamic-price market. A selection of results shows the viability and appropriateness of the presented stochastic optimization approaches for managing energy systems under uncertainty.

  18. Experience with bicoherence of electrical power for condition monitoring of wind turbine blades

    Energy Technology Data Exchange (ETDEWEB)

    Jeffries, W.Q.; Chambers, J.A. [Imperial College of Science, Technology and Medicine, London (United Kingdom). Dept. of Electrical and Electronic Engineering; Infield, D.G. [Loughborough University (United Kingdom). Centre for Renewable Energy Systems Tehnology

    1998-12-31

    The authors explore the application of the normalised bispectrum or bicoherence to the problem of condition monitoring of wind turbine blades. Background information is provided on this type of condition monitoring, how it differs from more conventional condition monitoring of turbo machinery, and the motivation for selecting bicoherence. Bicoherence is defined and compared with the power spectral density. Complications in collecting suitable data, and estimating the bicoherence from that data are investigated; including the requirements of very long stationary data sets for consistent estimates, and computational difficulties in handling such large data sets. Comparison of the results from the power spectral density and bicoherence indicates how the bicoherence might be employed for condition monitoring purposes. (author)

  19. Probabilistic Constrained Load Flow Considering Integration of Wind Power Generation and Electric Vehicles

    DEFF Research Database (Denmark)

    Vlachogiannis, Ioannis (John)

    2009-01-01

    are incorporated into load flow studies. In the resulted PCLF formulation, discrete and continuous control parameters are engaged. Therefore, a hybrid learning automata system (HLAS) is developed to find the optimal offline control settings over a whole planning period of power system. The process of HLAS...... integration of WT generation in correlation with EV demand/supply into the electricity grids are also introduced, resulting in the first benchmark. Novel conclusions for EV portfolio management are drawn....

  20. Superconducting Wind Turbine Generators

    OpenAIRE

    Yunying Pan; Danhzen Gu

    2016-01-01

    Wind energy is well known as a renewable energy because its clean and less polluted characteristic, which is the foundation of development modern wind electricity. To find more efficient wind turbine is the focus of scientists around the world. Compared from conventional wind turbines, superconducting wind turbine generators have advantages at zero resistance, smaller size and lighter weight. Superconducting wind turbine will inevitably become the main trends in this area. This paper intends ...

  1. The merit-order effect in the Italian power market: The impact of solar and wind generation on national wholesale electricity prices

    International Nuclear Information System (INIS)

    Clò, Stefano; Cataldi, Alessandra; Zoppoli, Pietro

    2015-01-01

    Italy promoted one of the most generous renewable support schemes worldwide which resulted in a high increase of solar power generation. We analyze the Italian day-ahead wholesale electricity market, finding empirical evidence of the merit-order effect. Over the period 2005–2013 an increase of 1 GWh in the hourly average of daily production from solar and wind sources has, on average, reduced wholesale electricity prices by respectively 2.3€/MWh and 4.2€/MWh and has amplified their volatility. The impact on prices has decreased over time in correspondence with the increase in solar and wind electricity production. We estimate that, over the period 2009–2013, solar production has generated higher monetary savings than wind production, mainly because the former is more prominent than the latter. However, in the solar case, monetary savings are not sufficient to compensate the cost of the related supporting schemes which are entirely internalized within end-user tariffs, causing a reduction of the consumer surplus, while the opposite occurs in the case of wind. - Highlights: • We find empirical evidence of the merit-order effect in the Italian market. • 1 GWh from solar and wind (hourly average) reduces prices by 2.3€/MW and 4.2€/MWh. • The impact of RES on price has declined as RES production has increased. • Monetary savings from solar production do not compensate the cost of the incentives. • Monetary savings from wind production are higher than the cost of the incentives

  2. X-Ray Analysis of the Proper Motion and Pulsar Wind Nebula for PSR J1741-2054

    Science.gov (United States)

    Auchettl, Katie; Slane, Patrick; Romani, Roger W.; Posselt, Bettina; Pavlov, George G.; Kargaltsev, Oleg; Ng, C-Y.; Temim, Tea; Weisskopf, Martin C.; Bykov, Andrei; hide

    2015-01-01

    We obtained six observations of PSR J1741-2054 using the Chandra ACIS-S detector totaling approx.300 ks. By registering this new epoch of observations to an archival observation taken 3.2 yr earlier using X-ray point sources in the field of view, we have measured the pulsar proper motion at micron = 109 +/- 10 mas yr(exp. -1) in a direction consistent with the symmetry axis of the observed H(alpha) nebula. We investigated the inferred past trajectory of the pulsar but find no compelling association with OB associations in which the progenitor may have originated. We confirm previous measurements of the pulsar spectrum as an absorbed power law with photon index gamma = 2.68 +/- 0.04, plus a blackbody with an emission radius of (4.5(+3.2/-2.5))d(0.38) km, for a DM-estimated distance of 0.38d(0.38) kpc and a temperature of 61.7 +/- 3.0 eV. Emission from the compact nebula is well described by an absorbed power law model with a photon index of gamma = 1.67 +/- 0.06, while the diffuse emission seen as a trail extending northeast of the pulsar shows no evidence of synchrotron cooling. We also applied image deconvolution techniques to search for small-scale structures in the immediate vicinity of the pulsar, but found no conclusive evidence for such structures.

  3. The combined value of wind and solar power forecasting improvements and electricity storage

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, Bri-Mathias; Brancucci Martinez-Anido, Carlo; Wang, Qin; Chartan, Erol; Florita, Anthony; Kiviluoma, Juha

    2018-03-01

    As the penetration rates of variable renewable energy increase, the value of power systems operation flexibility technology options, such as renewable energy forecasting improvements and electricity storage, is also assumed to increase. In this work, we examine the value of these two technologies, when used independently and concurrently, for two real case studies that represent the generation mixes for the California and Midcontinent Independent System Operators (CAISO and MISO). Since both technologies provide additional system flexibility they reduce operational costs and renewable curtailment for both generation mixes under study. Interestingly, the relative impacts are quite similar when both technologies are used together. Though both flexibility options can solve some of the same issues that arise with high penetration levels of renewables, they do not seem to significantly increase or decrease the economic potential of the other technology.

  4. Value of Flexible Resources, Virtual Bidding, and Self-Scheduling in Two-Settlement Electricity Markets With Wind Generation – Part I: Principles and Competitive Model

    DEFF Research Database (Denmark)

    Kazempour, Jalal; Hobbs, Benjamin F.

    2017-01-01

    Part one of this two-part paper presents new models for evaluating flexible resources in two-settlement electricity markets (day-ahead and real-time) with uncertain net loads (demand minus wind). Physical resources include wind together with fast- and slow-start demand response and thermal genera...... of certain equivalencies of the four models. We show how virtual bidding enhances market performance, since, together with self-scheduling by slow-start generators, it can help deterministic day-ahead market to choose the most efficient unit commitment....

  5. Performance of Generating Plant: Managing the Changes. Supporting paper: The evolution of the electricity sector and renewable sources in Italy: opportunities and problems for wind power integration

    Energy Technology Data Exchange (ETDEWEB)

    Salvaderi, Luigi [IEEE Fellow (Italy)

    2008-05-15

    The WEC Committee on the Performance of Generating Plant (PGP) has been collecting and analysing power plant performance statistics worldwide for more than 30 years and has produced regular reports, which include examples of advanced techniques and methods for improving power plant performance through benchmarking. A series of reports from the various working groups was issued in 2008. This document serves as a supporting paper. Sections include: features of Italian energy and electricity; the evolution of liberalisation; support mechanism for renewables; connection to wind farm transmission network; wind source integration into power system; and, final comments.

  6. Magnetically driven superluminal motion from rotating black holes. Solution of the magnetic wind equation in Kerr metric

    Science.gov (United States)

    Fendt, C.; Greiner, J.

    2001-04-01

    We have investigated magnetically driven superluminal jets originating from rotating black holes. The stationary, general relativistic, magnetohydrodynamic wind equation along collimating magnetic flux surfaces has been solved numerically. Our jet solutions are calculated on a global scale of a spatial range from several to several 1000 gravitational radii. Different magnetic field geometries were investigated, parameterized by the shape of the magnetic flux surface and the magnetic flux distribution. For a given magnetic flux surface we obtain the complete set of physical parameters for the jet flow. In particular, we apply our results to the Galactic superluminal sources GRS 1915+105 and GRO 1655-40. Motivated by the huge size indicated for the Galactic superluminal knots of about 109 Schwarzschild radii, we point out the possibility that the jet collimation process in these sources may be less efficient and therefore intrinsically different to the AGN. Our results show that the observed speed of more than 0.9 c can be achieved in general by magnetohydrodynamic acceleration. The velocity distribution along the magnetic field has a saturating profile. The asymptotic jet velocity depends either on the plasma magnetization (for a fixed field structure) or on the magnetic flux distribution (for fixed magnetization). The distance where the asymptotic velocity is reached, is below the observational resolution for GRS 1915+105 by several orders of magnitude. Further, we find that highly relativistic speeds can be reached also for jets not emerging from a region close to the black hole, if the flow magnetization is sufficiently large. The plasma temperature rapidly decreases from about 1010 K at the foot point of the jet to about 106 K at a distance of 5000 gravitational radii from the source. Temperature and the mass density follow a power law distribution with the radius. The jet magnetic field is dominated by the toroidal component, whereas the velocity field is

  7. A fuzzy chance-constrained program for unit commitment problem considering demand response, electric vehicle and wind power

    DEFF Research Database (Denmark)

    Zhang, Ning; Hu, Zhaoguang; Han, Xue

    2015-01-01

    , they can serve as reserve for wind power. To deal with the unit commitment problem, authors use a fuzzy chance- constrained program that takes into account the wind power forecasting errors. The numerical study shows that the model can promote the utilization of wind power evidently, making the power...

  8. Wind power

    International Nuclear Information System (INIS)

    Gipe, P.

    2007-01-01

    This book is a translation of the edition published in the USA under the title of ''wind power: renewable energy for home, farm and business''. In the wake of mass blackouts and energy crises, wind power remains a largely untapped resource of renewable energy. It is a booming worldwide industry whose technology, under the collective wing of aficionados like author Paul Gipe, is coming of age. Wind Power guides us through the emergent, sometimes daunting discourse on wind technology, giving frank explanations of how to use wind technology wisely and sound advice on how to avoid common mistakes. Since the mid-1970's, Paul Gipe has played a part in nearly every aspect of wind energy development from installing small turbines to promoting wind energy worldwide. As an American proponent of renewable energy, Gipe has earned the acclaim and respect of European energy specialists for years, but his arguments have often fallen on deaf ears at home. Today, the topic of wind power is cropping up everywhere from the beaches of Cape Cod to the Oregon-Washington border, and one wind turbine is capable of producing enough electricity per year to run 200 average American households. Now, Paul Gipe is back to shed light on this increasingly important energy source with a revised edition of Wind Power. Over the course of his career, Paul Gipe has been a proponent, participant, observer, and critic of the wind industry. His experience with wind has given rise to two previous books on the subject, Wind Energy Basics and Wind Power for Home and Business, which have sold over 50,000 copies. Wind Power for Home and Business has become a staple for both homeowners and professionals interested in the subject, and now, with energy prices soaring, interest in wind power is hitting an all-time high. With chapters on output and economics, Wind Power discloses how much you can expect from each method of wind technology, both in terms of energy and financial savings. The book updated models

  9. Enhancing consumers' voluntary use of small-scale wind turbines to generate own electricity in South Africa

    OpenAIRE

    Brendan Whelan; Edwin Muchapondwa

    2009-01-01

    This paper investigates whether South African households and small businesses can take advantage of the country’s substantial wind resources to produce their own power from small-scale wind turbines in a viable way. The viability of small-scale wind turbines is assessed by means of a financial analysis based on the internal rate of return method. The recently announced wind feed-in tariff will not affect the viability of consumer-based small-scale wind turbines considered in this paper sinc...

  10. Model for the techno-economic analysis of common work of wind power and CCGT power plant to offer constant level of power in the electricity market

    Science.gov (United States)

    Tomsic, Z.; Rajsl, I.; Filipovic, M.

    2017-11-01

    Wind power varies over time, mainly under the influence of meteorological fluctuations. The variations occur on all time scales. Understanding these variations and their predictability is of key importance for the integration and optimal utilization of wind in the power system. There are two major attributes of variable generation that notably impact the participation on power exchanges: Variability (the output of variable generation changes and resulting in fluctuations in the plant output on all time scales) and Uncertainty (the magnitude and timing of variable generation output is less predictable, wind power output has low levels of predictability). Because of these variability and uncertainty wind plants cannot participate to electricity market, especially to power exchanges. For this purpose, the paper presents techno-economic analysis of work of wind plants together with combined cycle gas turbine (CCGT) plant as support for offering continues power to electricity market. A model of wind farms and CCGT plant was developed in program PLEXOS based on real hourly input data and all characteristics of CCGT with especial analysis of techno-economic characteristics of different types of starts and stops of the plant. The Model analyzes the followings: costs of different start-stop characteristics (hot, warm, cold start-ups and shutdowns) and part load performance of CCGT. Besides the costs, the technical restrictions were considered such as start-up time depending on outage duration, minimum operation time, and minimum load or peaking capability. For calculation purposes, the following parameters are necessary to know in order to be able to economically evaluate changes in the start-up process: ramp up and down rate, time of start time reduction, fuel mass flow during start, electricity production during start, variable cost of start-up process, cost and charges for life time consumption for each start and start type, remuneration during start up time regarding

  11. Turbulence and wind turbines

    DEFF Research Database (Denmark)

    Brand, Arno J.; Peinke, Joachim; Mann, Jakob

    2011-01-01

    The nature of turbulent flow towards, near and behind a wind turbine, the effect of turbulence on the electricity production and the mechanical loading of individual and clustered wind turbines, and some future issues are discussed.......The nature of turbulent flow towards, near and behind a wind turbine, the effect of turbulence on the electricity production and the mechanical loading of individual and clustered wind turbines, and some future issues are discussed....

  12. Plug-in hybrid electric vehicles as a way to maximize the integration of variable renewable energy in power systems: The case of wind generation in northeastern Brazil

    International Nuclear Information System (INIS)

    Soares MC Borba, Bruno; Szklo, Alexandre; Schaeffer, Roberto

    2012-01-01

    Several studies have proposed different tools for analyzing the integration of variable renewable energy into power grids. This study applies an optimization tool to model the expansion of the electric power system in northeastern Brazil, enabling the most efficient dispatch of the variable output of the wind farms that will be built in the region over the next 20 years. The expected combined expansion of wind generation with conventional inflexible generation facilities, such as nuclear plants and run-of-the-river hydropower plants, poses risks of future mismatch between supply and demand in northeastern Brazil. Therefore, this article evaluates the possibility of using a fleet of plug-in hybrid electric vehicles (PHEVs) to regularize possible energy imbalances. Findings indicate that a dedicated fleet of 500 thousand PHEVs in 2015, and a further 1.5 million in 2030, could be recharged overnight to take advantage of the surplus power generated by wind farms. To avoid the initial costs of smart grids, this article suggests, as a first step, the use of a governmental PHEV fleet that allows fleet managers to control battery charging times. Finally, the study demonstrates the advantages of optimizing simultaneously the power and transport sectors to test the strategy suggested here. -- Highlights: ► We evaluated the use of plug-in hybrid electric vehicles (PHEV) to regularize possible energy imbalances in northeastern Brazil. ► This imbalance might result from the large-scale wind power penetration along with conventional inflexible power plants in the region. ► We adapted the MESSAGE optimization tool to the base conditions of the Brazilian power system. ► 500 thousand PHEVs in 2015 and 1.5 million in 2030 could be recharged taking advantage of wind energy surplus.

  13. Electric Circuit Model for the Aerodynamic Performance Analysis of a Three-Blade Darrieus-Type Vertical Axis Wind Turbine: The Tchakoua Model

    Directory of Open Access Journals (Sweden)

    Pierre Tchakoua

    2016-10-01

    Full Text Available The complex and unsteady aerodynamics of vertical axis wind turbines (VAWTs pose significant challenges for simulation tools. Recently, significant research efforts have focused on the development of new methods for analysing and optimising the aerodynamic performance of VAWTs. This paper presents an electric circuit model for Darrieus-type vertical axis wind turbine (DT-VAWT rotors. The novel Tchakoua model is based on the mechanical description given by the Paraschivoiu double-multiple streamtube model using a mechanical‑electrical analogy. Model simulations were conducted using MATLAB for a three-bladed rotor architecture, characterized by a NACA0012 profile, an average Reynolds number of 40,000 for the blade and a tip speed ratio of 5. The results obtained show strong agreement with findings from both aerodynamic and computational fluid dynamics (CFD models in the literature.

  14. Quantum Effects of Electric Fields and Potentials on Electron Motion: An Introduction to Theoretical and Practical Aspects

    Science.gov (United States)

    Matteucci, G.

    2007-01-01

    In the so-called electric Aharonov-Bohm effect, a quantum interference pattern shift is produced when electrons move in an electric field free region but, at the same time, in the presence of a time-dependent electric potential. Analogous fringe shifts are observed in interference experiments where electrons, travelling through an electrostatic…

  15. Mounting and performance measurements of a PV array addition to an existing small wind-power installation for greenhouse electric supply in Patagonia

    Directory of Open Access Journals (Sweden)

    Rafael Oliva

    2016-08-01

    Full Text Available A small wind-power system intended for electric supply of a research greenhouse at the local University facilities in San Julian region incorporates a photovoltaic (PV array and regulator, which is described in this report together with its data-acquisition system. The main application is control and lighting. The Alternative Energy Group at the University seeks through this project to acquire knowledge and practical experience in the combination of renewable energy sources for optimal electrical supply of isolated systems, their associated measurements and processing of resulting data

  16. Effect of electric fields on the stabilization of premixed laminar bunsen flames at low AC frequency: Bi-ionic wind effect

    KAUST Repository

    Kim, Minkuk

    2012-03-01

    The stabilization characteristics of laminar premixed bunsen flames have been investigated experimentally by applying AC electric fields at low frequency below 60. Hz together with DC in the single electrode configuration. The blowoff velocity has been measured for varying AC voltage and frequency. A transition frequency between low and high frequency regimes has been identified near 40-50. Hz, where AC electric fields have minimal effect on flame stabilization. In the low frequency regime, the blowoff velocity decreased linearly with AC voltage such that the flames became less stable. This was consistent with the DC result, implying the influence of the ionic wind effect. The variation of blowoff velocity with AC frequency showed a non-monotonic behavior in that the velocity decreased and then increased, exhibiting minimum blowoff velocity near 6-8. Hz. Based on the molecular kinetic theory, the developing degree of ionic wind was derived. By considering the ionic wind effects arising from both positive and negative ions in a flame zone, the bi-ionic wind effect successfully explained the non-monotonic behavior of blowoff velocity with AC frequency in the low frequency regime. © 2011 The Combustion Institute.

  17. Wind energy

    CERN Document Server

    Woll, Kris

    2016-01-01

    Across the country, huge open spaces are covered in gently turning wind turbines. In Wind Energy, explore how these machines generate electricity, learn about the history of wind power, and discover the latest advances in the field. Easy-to-read text, vivid images, and helpful back matter give readers a clear look at this subject. Features include a table of contents, infographics, a glossary, additional resources, and an index. Aligned to Common Core Standards and correlated to state standards. Core Library is an imprint of Abdo Publishing, a division of ABDO.

  18. How Does Energy Storage Increase the Efficiency of an Electricity Market with Integrated Wind and Solar Power Generation?—A Case Study of Korea

    Directory of Open Access Journals (Sweden)

    Jung Youn Mo

    2017-10-01

    Full Text Available In recent years, increasing requests to reduce greenhouse gas emissions have led to renewable resources rapidly replacing conventional power sources. However, the inherent variability of renewable sources reduces the reliability of power systems. Energy storage has been proposed as a viable alternative, as it can mitigate the variability of renewable energy sources and increase the efficiency of power systems by lowering peak electricity demand. In this study, we evaluate the benefits of integrating energy storage with combined wind and solar power generation in the Korean power system through using the dynamic optimization method. Realistic wind and photovoltaic solar power generation scenarios were estimated for actual sites. The results show that the wind power-based system benefitted more from energy storage than the combined wind and solar photovoltaic power-based system. This is because the high variability of wind power was reduced when it was combined with solar power. Co-optimization for energy and reserve costs was more beneficial than optimization for energy costs alone, which suggests that the reliability offered by storage is an important cost-saving factor, in addition to the reduction of energy costs by price arbitrage. Finally, the analysis was conducted under various scenarios to determine the validity of energy storage cost effectiveness.

  19. Multiobjective Synergistic Scheduling Optimization Model for Wind Power and Plug-In Hybrid Electric Vehicles under Different Grid-Connected Modes

    Directory of Open Access Journals (Sweden)

    Liwei Ju

    2014-01-01

    Full Text Available In order to promote grid’s wind power absorptive capacity and to overcome the adverse impacts of wind power on the stable operation of power system, this paper establishes benefit contrastive analysis models of wind power and plug-in hybrid electric vehicles (PHEVs under the optimization goal of minimum coal consumption and pollutant emission considering multigrid connected modes. Then, a two-step adaptive solving algorithm is put forward to get the optimal system operation scheme with the highest membership degree based on the improved ε constraints method and fuzzy decision theory. Thirdly, the IEEE36 nodes 10-unit system is used as the simulation system. Finally, the sensitive analysis for PHEV’s grid connected number is made. The result shows the proposed algorithm is feasible and effective to solve the model. PHEV’s grid connection could achieve load shifting effect and promote wind power grid connection. Especially, the optimization goals reach the optimum in fully optimal charging mode. As PHEV’s number increases, both abandoned wind and thermal power generation cost would decrease and the peak and valley difference of load curve would gradually be reduced.

  20. Secondary contamination of 30-km zone of the Chernobyl atomic electric plant and adjacent territory due to radionuclides carried by ascending wind

    International Nuclear Information System (INIS)

    Garger, E.K.; Gavrilov, V.P.

    1992-01-01

    The territory contaminated with radionuclides as a result of the accident at the Chernobyl atomic electric plant is a surface source of radioactive aerosols carried into the atmosphere by ascending winds. In this connection, a number of problems arise whose solution is important for assessment of the radiation conditions in the atmosphere near the Earth's surface: (1) calculation of the volume concentration of radionuclides and their fallout on the contaminated and neighboring territory and on this basis determine the potentially dangerous contaminated regions; (2) assessment of the secondary contamination of deactivated territories due to ascending winds and transfer of radionuclides; and (3) determination of the size of the protective (buffer) zones around or near populated areas to ensure low volume concentrations of radionuclides during strong winds. In order to calculate the transfer of radionuclides from a surface source, it is necessary to know its dust intensity, which is the vertical turbulent flux of the radionuclides in the atmosphere layer near the ground Q (Ci · m -2 sec -1 ). A quantity frequently used in practice is Q referred to the contamination density of the surface layer c (Ci/m 2 ) and called the wind ascent intensity α = Q/c. As a rule, the radionuclide wind ascent intensity for a plane source with a nonuniform surface and contamination density may depend on the physical characteristics of the surface as well as on those of the radionuclides and also on the space coordinates x, y and on time. In the present study, the wind ascent intensity was determined by gradient measurements of the mean radionuclide concentration, the wind velocity and air temperature; the conditions during the measurements were assumed to correspond to the case of a plane homogeneous, stationary source of a nondepositing admixture