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

large wind farms, winds can decrease considerably from their free-stream values to a point where an equilibrium wind speed is reached. The magnitude of this equilibrium wind speed is primarily dependent on the balance between turbine drag force and the downward momentum influx from above the wind farm......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...

Modern wind energy technology for Russian applications. Main report

DEFF Research Database (Denmark)

Madsen, Peter Hauge; Winther-Jensen, Martin; Bindner, Henrik W.

1999-01-01

The general objective of the project is to establish a technical foundation for an intensified application of wind energy in Russia with medium to large wind turbines and transfer/adaptation of Danish and European wind turbine technology as a basis forfuture joint ventures and technology exports...... climate and in-land sites of Russia. As part of this work it is necessary to clarify the types of operationalconditions and requirements that are to be met by wind turbines operating in such conditions, and to outline suitable test procedures and test set-up’s for verifications of such adapted...

Technology Development and Innovation | Wind | NREL

Science.gov (United States)

Technology Development and Innovation Technology Development and Innovation Technology Development Technology Center (NWTC) supports efforts to reduce bird and bat fatalities at wind energy projects and photo of wind turbines at the National Wind Technology Center. Wildlife technology research and

FY 1998 Report on development of large-scale wind power generation systems. Feasibility study on development of new technologies for wind power generation (Study on the development of wind power generation); 1998 nendo ogata furyoku hatsuden system kaihatsu. Furyoku hatsuden shingijutsu kaihatsu kanosei chosa (furyoku hatsuden gijutsu ni kansuru kaihatsu doko chosa)

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

This survey is designed to analyze, e.g., current status of large-scale wind power generation devices/system technologies and development trends worldwide, and to make predictions about future developments, in an effort to contribute to advancements in new technology for wind power generation systems in Japan. The international R and D cooperation programs promoted by IEA and EU have helped the participants produce a number of good results at lower costs. The European countries have developed the wind power generation industries in each area, promoted by the governmental subsidy policies, and are leading the world. The system is becoming larger, from around an average unit capacity of 250kW in the beginning of the 90's to 600kW now, reducing the cost by the scale merit. The improved computer capacity has made it possible to more easily analyze the complicated rotor aerodynamics, structural dynamics, wind characteristics and other factors related to wind power generation systems. The future R and D directions will include world standards for large-scale wind turbines, advancements in wind farm technologies, offshore wind power generation systems, advancement in design technologies, and new concepts for wind power turbine designs, e.g., floating wind turbine. (NEDO)

Technology assessment of wind energy conversion systems

Energy Technology Data Exchange (ETDEWEB)

Meier, B. W.; Merson, T. J.

1980-09-01

Environmental data for wind energy conversion systems (WECSs) have been generated in support of the Technology Assessment of Solar Energy (TASE) program. Two candidates have been chosen to characterize the WECS that might be deployed if this technology makes a significant contribution to the national energy requirements. One WECS is a large machine of 1.5-MW-rated capacity that can be used by utilities. The other WECS is a small machine that is characteristic of units that might be used to meet residential or small business energy requirements. Energy storage systems are discussed for each machine to address the intermittent nature of wind power. Many types of WECSs are being studied and a brief review of the technology is included to give background for choosing horizontal axis designs for this study. Cost estimates have been made for both large and small systems as required for input to the Strategic Environmental Assessment Simulation (SEAS) computer program. Material requirements, based on current generation WECSs, are discussed and a general discussion of environmental impacts associated with WECS deployment is presented.

OffshoreDC DC grids for integration of large scale wind power

DEFF Research Database (Denmark)

Zeni, Lorenzo; Endegnanew, Atsede Gualu; Stamatiou, Georgios

The present report summarizes the main findings of the Nordic Energy Research project “DC grids for large scale integration of offshore wind power – OffshoreDC”. The project is been funded by Nordic Energy Research through the TFI programme and was active between 2011 and 2016. The overall...... objective of the project was to drive the development of the VSC based HVDC technology for future large scale offshore grids, supporting a standardised and commercial development of the technology, and improving the opportunities for the technology to support power system integration of large scale offshore...

2014 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Wiser, R; Bolinger, M.

2015-08-01

According to the 2014 Wind Technologies Market Report, total installed wind power capacity in the United States grew at a rate of eight percent in 2014, bringing the United States total installed capacity to nearly 66 gigawatts (GW), which ranks second in the world and meets 4.9 percent of U.S. end-use electricity demand in an average year. In total, 4,854 MW of new wind energy capacity were installed in the United States in 2014. The 2014 Wind Technologies Market Report also finds that wind energy prices are at an all-time low and are competitive with wholesale power prices and traditional power sources across many areas of the United States. Additionally, a new trend identified by the 2014 Wind Technologies Market Report shows utility-scale turbines with larger rotors designed for lower wind speeds have been increasingly deployed across the country in 2014. The findings also suggest that the success of the U.S. wind industry has had a ripple effect on the American economy, supporting 73,000 jobs related to development, siting, manufacturing, transportation, and other industries.

Siemens Wind Power 3.6 MW wind turbines for large offshore wind farms

Energy Technology Data Exchange (ETDEWEB)

Akhmatov, Vladislav; Nygaard Nielsen, Joergen; Thisted, Jan; Groendahl, Erik; Egedal, Per; Noertoft Frydensbjerg, Michael; Jensen, Kim Hoej [Siemens Wind Power A/S, Brande (Denmark)

2008-07-01

Siemens Wind power A/S is the key player on the offshore wind power market. The Siemens Wind Power 3.6 MW variable-speed wind turbine is among the word's largest, most advanced and competitive wind turbines with a solid portfolio of large offshore wind farms. Transmission system operators and developers require dynamic wind turbine models for evaluation of fault-ride-through capability and investigations of power system stability. The even larger size of the on- and offshore wind farms has entailed that the grid impact of the voltage and frequency control capability of the wind farm can be appropriated modelled and evaluated. Siemens Wind Power has developed a dynamic model of the 3.6 MW variable-speed wind turbine with the fault-ride-through sequences and models of the voltage and frequency controllers to be applied for large offshore wind farms. The dynamic models have been implemented in the commercially available simulation tools such as DIgSILENT PowerFactory and Siemens PTI PSS/E and successfully validated from measurements. (orig.)

Emerging wind energy technologies

DEFF Research Database (Denmark)

Rasmussen, Flemming; Grivel, Jean-Claude; Faber, Michael Havbro

2014-01-01

This chapter will discuss emerging technologies that are expected to continue the development of the wind sector to embrace new markets and to become even more competitive.......This chapter will discuss emerging technologies that are expected to continue the development of the wind sector to embrace new markets and to become even more competitive....

Wind Penetration with different wind turbine technologies in a weak grid

International Nuclear Information System (INIS)

Santos Fuentefria, Ariel; Castro Fernandez, Miguel A.; Martínez García, Antonio

2012-01-01

The insertion of wind energy into electric network may provoke stability problems due to stochastic character of wind. The variation in the wind causes voltage variation in the Point of Common Coupling (PCC). In a weakest system that variation is high. Another important factor is wind turbine technology. The use of grid-connected fixed speed wind generator introduces a great consumption of reactive power that can be compensated using different devices as capacitors bank or static var compensator (SVC or STATCOM). In the other hand the variable speed wind turbine have an electronic converter to control the reactive consumption to maintain the PCC voltage more stable. In this paper a comparison between the different types of wind turbines technology is show. It's analyzing the impact in wind power limit for different wind turbine technologies in a weak system. (author)

Opportunities for Canadian stakeholders in the North American large wind turbine supply chain

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-01

Wind energy is the fastest growing source of electricity in terms of annual installed capacity. This report presented a study of the North American large wind turbine generator supply chain and technological innovation challenges, and identified opportunities for Canadian industrial and research stakeholders to increase their participation in the wind industry. The study was conducted in three phases. The report described each of these phases, which included identification of the North American turbine supply chain needs and opportunities and its technological innovation challenges; identification of Canadian industrial and research stakeholders, either currently involved in the wind sector or external to it, which had strong transferable skills or capabilities to respond to the specific opportunities; and an assessment of the overall likelihood of Canadian stakeholders being able to respond to specific opportunities within the large wind turbine manufacturing segment of the supply chain. The report provided a market overview of the global, American and Canadian markets and discussed the key North American market drivers and potential economic benefits of wind power. The report also presented an overview of drivers for success in major markets jurisdictions and discussed the large wind turbine supply chain. Several strategic recommendations were offered, such as establishing and maintaining an open line of communication with key contacts within prime contractor and component manufacturer organizations; and maintaining and strengthening wind market policies and creating long-term market signals. refs., tabs., figs.

Wind power production: from the characterisation of the wind resource to wind turbine technologies

International Nuclear Information System (INIS)

Beslin, Guy; Multon, Bernard

2016-01-01

Illustrated by graphs and tables, this article first describes the various factors and means related to the assessment of wind resource in the World, in Europe, and the factors which characterize a local wind resource. In this last respect, the authors indicate how local topography is taken into account to calculate wind speed, how time variations are taken into account (at the yearly, seasonal or daily level), the different methods used to model a local wind resource, how to assess the power recoverable by a wind turbine with horizontal axis (notion of Betz limit). In the second part, the authors present the different wind turbines, their benefits and drawbacks: vertical axis, horizontal axis (examples of a Danish-type wind turbine, of wind turbines designed for extreme conditions). Then, they address the technology of big wind turbines: evolution of technology and of commercial offer, aerodynamic characteristics of wind turbine and benefit of a varying speed (technological solutions, importance of the electric generator). They describe how to choose a wind turbine, how product lines are organised, how the power curve and energy capacity are determined. The issue of integration of wind energy into the power system is then addressed. The next part addressed the economy of wind energy production (annualized production cost, order of magnitude of wind electric power production cost). Future trends are discussed and offshore wind energy production is briefly addressed

Advances in wind energy conversion technology

CERN Document Server

Sathyajith, Mathew

2011-01-01

The technology of generating energy from wind has significantly changed during the past five years. The book brings together all the latest aspects of wind energy conversion technology - from wind resource analysis to grid integration of generated electricity.

Potential climatic impacts and reliability of very large-scale wind farms

Directory of Open Access Journals (Sweden)

C. Wang

2010-02-01

Full Text Available Meeting future world energy needs while addressing climate change requires large-scale deployment of low or zero greenhouse gas (GHG emission technologies such as wind energy. The widespread availability of wind power has fueled substantial interest in this renewable energy source as one of the needed technologies. For very large-scale utilization of this resource, there are however potential environmental impacts, and also problems arising from its inherent intermittency, in addition to the present need to lower unit costs. To explore some of these issues, we use a three-dimensional climate model to simulate the potential climate effects associated with installation of wind-powered generators over vast areas of land or coastal ocean. Using wind turbines to meet 10% or more of global energy demand in 2100, could cause surface warming exceeding 1 °C over land installations. In contrast, surface cooling exceeding 1 °C is computed over ocean installations, but the validity of simulating the impacts of wind turbines by simply increasing the ocean surface drag needs further study. Significant warming or cooling remote from both the land and ocean installations, and alterations of the global distributions of rainfall and clouds also occur. These results are influenced by the competing effects of increases in roughness and decreases in wind speed on near-surface turbulent heat fluxes, the differing nature of land and ocean surface friction, and the dimensions of the installations parallel and perpendicular to the prevailing winds. These results are also dependent on the accuracy of the model used, and the realism of the methods applied to simulate wind turbines. Additional theory and new field observations will be required for their ultimate validation. Intermittency of wind power on daily, monthly and longer time scales as computed in these simulations and inferred from meteorological observations, poses a demand for one or more options to ensure

Modern wind energy technology for Russian applications. Main report

Energy Technology Data Exchange (ETDEWEB)

Hauge Madsen, P.; Winther-Jensen, M., Bindner, H.W. [and others

1999-05-01

The general objective of the project is to establish a technical foundation for an intensified application of wind energy in Russia with medium to large wind turbines and transfer/adaptation of Danish and European wind turbine technology as a basis for future joint ventures and technology exports. More specifically, the objective is to develop and establish the basic knowledge and design criteria for adaptation and development of Danish wind turbine technology for application under Russian conditions. The research programme is envisaged to be carried out in three phases, the first phase being the project reported herein. The main purpose of phase 1 is to assess the needs for modifications and adaptations of established standard (in casu Danish) wind turbine designs for decentralised energy systems with a limited number of medium sized wind turbines and for grid connected wind turbines in cold climate and in-land sites of Russia. As part of this work it is necessary to clarify the types of operational conditions and requirements that are to be met by wind turbines operating in such conditions, and to outline suitable test procedures and test set-up is for verifications of such adapted and modified wind turbines. The reporting of this project is made in one main report and four topical reports, all of them issued as Risoe reports. This is the Main Report, (Risoe-R-1069), summing up the activities and findings of phase 1 and outlining a strategy for Russian-Danish cooperation in wind energy as agreed upon between the Russian and the Danish parties. (au)

Wind Energy: Trends And Enabling Technologies

Energy Technology Data Exchange (ETDEWEB)

Devabhaktuni, Vijay; Alam, Mansoor; Boyapati, Premchand; Chandna, Pankaj; Kumar, Ashok; Lack, Lewis; Nims, Douglas; Wang, Lingfeng

2010-09-15

With attention now focused on the damaging impact of greenhouse gases, wind energy is rapidly emerging as a low carbon, resource efficient, cost-effective sustainable technology in many parts of the world. Despite higher economic costs, offshore appears to be the next big step in wind energy development alternative because of the space scarcity for installation of onshore wind turbine. This paper presents the importance of off-shore wind energy, the wind farm layout design, the off-shore wind turbine technological developments, the role of sensors and the smart grid, and the challenges and future trends of wind energy.

Large fully retractable telescope enclosures still closable in strong wind

Science.gov (United States)

Bettonvil, Felix C. M.; Hammerschlag, Robert H.; Jägers, Aswin P. L.; Sliepen, Guus

2008-07-01

Two prototypes of fully retractable enclosures with diameters of 7 and 9 m have been built for the high-resolution solar telescopes DOT (Dutch Open Telescope) and GREGOR, both located at the Canary Islands. These enclosures protect the instruments for bad weather and are fully open when the telescopes are in operation. The telescopes and enclosures also operate in hard wind. The prototypes are based on tensioned membrane between movable but stiff bows, which fold together to a ring when opened. The height of the ring is small. The prototypes already survived several storms, with often snow and ice, without any damage, including hurricane Delta with wind speeds up to 68 m/s. The enclosures can still be closed and opened with wind speeds of 20 m/s without any problems or restrictions. The DOT successfully demonstrated the open, wind-flushing concept for astronomical telescopes. It is now widely recognized that also large future telescopes benefit from wind-flushing and retractable enclosures. These telescopes require enclosures with diameters of 30 m until roughly 100 m, the largest sizes for the ELTs (Extreme Large Telescopes), which will be built in the near future. We discuss developments and required technology for the realization of these large sizes.

High Power Density Power Electronic Converters for Large Wind Turbines

DEFF Research Database (Denmark)

Senturk, Osman Selcuk

. For these VSCs, high power density is required due to limited turbine nacelle space. Also, high reliability is required since maintenance cost of these remotely located wind turbines is quite high and these turbines operate under harsh operating conditions. In order to select a high power density and reliability......In large wind turbines (in MW and multi-MW ranges), which are extensively utilized in wind power plants, full-scale medium voltage (MV) multi-level (ML) voltage source converters (VSCs) are being more preferably employed nowadays for interfacing these wind turbines with electricity grids...... VSC solution for wind turbines, first, the VSC topology and the switch technology to be employed should be specified such that the highest possible power density and reliability are to be attained. Then, this qualitative approach should be complemented with the power density and reliability...

Technological learning in offshore wind energy: Different roles of the government

NARCIS (Netherlands)

Smit, T.; Junginger, M.; Smits, R.E.H.M.

2007-01-01

Offshore wind energy is a promising source of renewable electricity, even though its current costs prevent large-scale implementation. Technological learning has improved the technology and its economic performance already, and could result in significant further improvements. This study

Numerical Buckling Analysis of Large Suction Caissons for Wind Turbines on Deep Water

DEFF Research Database (Denmark)

Madsen, Søren; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

2013-01-01

Using large suction caissons for offshore wind turbines is an upcoming cost-effective technology also referred to as bucket foundations. During operation, the monopod bucket foundation is loaded by a large overturning moment from the wind turbine and the wave loads. However, during installation...... the suction caisson is loaded by external pressure (internal suction) due to evacuation of water inside the bucket and vertical forces due to gravity. The risk of structural buckling during installation of large-diameter suction caissons is addressed using numerical methods. Initial imperfect geometries...

From technology transfer to local manufacturing: China's emergence in the global wind power industry

Science.gov (United States)

Lewis, Joanna Ingram

This dissertation examines the development of China's large wind turbine industry, including the players, the status of the technology, and the strategies used to develop turbines for the Chinese market. The primary goals of this research project are to identify the models of international technology transfer that have been used among firms in China's wind power industry; examine to what extent these technology transfers have contributed to China's ability to locally manufacture large wind turbine technology; and evaluate China's ability to become a major player in the global wind industry. China is a particularly important place to study the opportunities for and dynamics of clean energy development due to its role in global energy consumption. China is the largest coal consuming and producing nation in the world, and consequently the second largest national emitter of carbon dioxide after only the United States. Energy consumption and carbon emissions are growing rapidly, and China is expected to surpass the US and become the largest energy consuming nation and carbon dioxide emitter in coming decades. The central finding of this dissertation is that even though each firm involved in the large wind turbine manufacturing industry in China has followed a very different pathway of technology procurement for the Chinese market, all of the firms are increasing the utilization of locally-manufactured components, and many are doing so without transferring turbine technology or the associated intellectual property. Only one fully Chinese-owned firm, Goldwind, has succeeded in developing a commercially available large wind turbine for the Chinese market. No Chinese firms or foreign firms are manufacturing turbines in China for export overseas, though many have stated plans to do so. There already exists a possible niche market for the smaller turbines that are currently being made in China, particularly in less developed countries that are looking for less expensive

Accident of Large-scale Wind Turbines Disconnecting from Power Grid and Its Protection

Institute of Scientific and Technical Information of China (English)

2012-01-01

There were many accidents of large-scale wind turbines disconnecting from power grid in 2011. As single- phase-to-ground fault cannot be correctly detected, single-phase-to-ground fault evolved to phase-to-phase fault. Phase-to-phase fault was isolated slowly, thus leading to low voltage. And wind turbines without enough low voltage ride-through capacity had to be disconnected from the grid. After some wind turbines being disconnected from the grid, overvoltage caused by reactive power surplus made more wind turbines disconnect from the grid. Based on the accident analysis, this paper presents solutions to above problems, including travelling waves based single-phase-to-ground protection, adaptive low voltage protection, integrated protection and control, and high impedance fault detection. The solutions lay foundations in theory and technology to prevent large-scale wind turbines disconnecting from the operating power grid.

Potential climatic impacts and reliability of large-scale offshore wind farms

International Nuclear Information System (INIS)

Wang Chien; Prinn, Ronald G

2011-01-01

The vast availability of wind power has fueled substantial interest in this renewable energy source as a potential near-zero greenhouse gas emission technology for meeting future world energy needs while addressing the climate change issue. However, in order to provide even a fraction of the estimated future energy needs, a large-scale deployment of wind turbines (several million) is required. The consequent environmental impacts, and the inherent reliability of such a large-scale usage of intermittent wind power would have to be carefully assessed, in addition to the need to lower the high current unit wind power costs. Our previous study (Wang and Prinn 2010 Atmos. Chem. Phys. 10 2053) using a three-dimensional climate model suggested that a large deployment of wind turbines over land to meet about 10% of predicted world energy needs in 2100 could lead to a significant temperature increase in the lower atmosphere over the installed regions. A global-scale perturbation to the general circulation patterns as well as to the cloud and precipitation distribution was also predicted. In the later study reported here, we conducted a set of six additional model simulations using an improved climate model to further address the potential environmental and intermittency issues of large-scale deployment of offshore wind turbines for differing installation areas and spatial densities. In contrast to the previous land installation results, the offshore wind turbine installations are found to cause a surface cooling over the installed offshore regions. This cooling is due principally to the enhanced latent heat flux from the sea surface to lower atmosphere, driven by an increase in turbulent mixing caused by the wind turbines which was not entirely offset by the concurrent reduction of mean wind kinetic energy. We found that the perturbation of the large-scale deployment of offshore wind turbines to the global climate is relatively small compared to the case of land

Wind Data Analysis and Wind Flow Simulation Over Large Areas

Directory of Open Access Journals (Sweden)

Terziev Angel

2014-03-01

Full Text Available Increasing the share of renewable energy sources is one of the core policies of the European Union. This is because of the fact that this energy is essential in reducing the greenhouse gas emissions and securing energy supplies. Currently, the share of wind energy from all renewable energy sources is relatively low. The choice of location for a certain wind farm installation strongly depends on the wind potential. Therefore the accurate assessment of wind potential is extremely important. In the present paper an analysis is made on the impact of significant possible parameters on the determination of wind energy potential for relatively large areas. In the analysis the type of measurements (short- and long-term on-site measurements, the type of instrumentation and the terrain roughness factor are considered. The study on the impact of turbulence on the wind flow distribution over complex terrain is presented, and it is based on the real on-site data collected by the meteorological tall towers installed in the northern part of Bulgaria. By means of CFD based software a wind map is developed for relatively large areas. Different turbulent models in numerical calculations were tested and recommendations for the usage of the specific models in flows modeling over complex terrains are presented. The role of each parameter in wind map development is made. Different approaches for determination of wind energy potential based on the preliminary developed wind map are presented.

Power fluctuations from large wind farms - Final report

Energy Technology Data Exchange (ETDEWEB)

Soerensen, Poul; Pinson, P.; Cutululis, N.A.; Madsen, Henrik; Jensen, Leo Enrico; Hjerrild, J.; Heyman Donovan, M.; Vigueras-ROdriguez, A.

2009-08-15

Experience from power system operation with the first large offshore wind farm in Denmark: Horns Rev shows that the power from the wind farm is fluctuating significantly at certain times, and that this fluctuation is seen directly on the power exchange between Denmark and Germany. This report describes different models for simulation and prediction of wind power fluctuations from large wind farms, and data acquired at the two large offshore wind farms in Denmark are applied to validate the models. Finally, the simulation model is further developed to enable simulations of power fluctuations from several wind farms simultaneously in a larger geographical area, corresponding to a power system control area. (au)

Contribution of large scale coherence to wind turbine power: A large eddy simulation study in periodic wind farms

Science.gov (United States)

Chatterjee, Tanmoy; Peet, Yulia T.

2018-03-01

Length scales of eddies involved in the power generation of infinite wind farms are studied by analyzing the spectra of the turbulent flux of mean kinetic energy (MKE) from large eddy simulations (LES). Large-scale structures with an order of magnitude bigger than the turbine rotor diameter (D ) are shown to have substantial contribution to wind power. Varying dynamics in the intermediate scales (D -10 D ) are also observed from a parametric study involving interturbine distances and hub height of the turbines. Further insight about the eddies responsible for the power generation have been provided from the scaling analysis of two-dimensional premultiplied spectra of MKE flux. The LES code is developed in a high Reynolds number near-wall modeling framework, using an open-source spectral element code Nek5000, and the wind turbines have been modelled using a state-of-the-art actuator line model. The LES of infinite wind farms have been validated against the statistical results from the previous literature. The study is expected to improve our understanding of the complex multiscale dynamics in the domain of large wind farms and identify the length scales that contribute to the power. This information can be useful for design of wind farm layout and turbine placement that take advantage of the large-scale structures contributing to wind turbine power.

Technology Roadmaps: Wind Energy

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

Wind energy is perhaps the most advanced of the 'new' renewable energy technologies, but there is still much work to be done. This roadmap identifies the key tasks that must be undertaken in order to achieve a vision of over 2 000 GW of wind energy capacity by 2050. Governments, industry, research institutions and the wider energy sector will need to work together to achieve this goal. Best technology and policy practice must be identified and exchanged with emerging economy partners, to enable the most cost-effective and beneficial development.

The economics and environmental impacts of large-scale wind power in a carbon constrained world

Science.gov (United States)

Decarolis, Joseph Frank

Serious climate change mitigation aimed at stabilizing atmospheric concentrations of CO2 will require a radical shift to a decarbonized energy supply. The electric power sector will be a primary target for deep reductions in CO2 emissions because electric power plants are among the largest and most manageable point sources of emissions. With respect to new capacity, wind power is currently one of the most inexpensive ways to produce electricity without CO2 emissions and it may have a significant role to play in a carbon constrained world. Yet most research in the wind industry remains focused on near term issues, while energy system models that focus on century-long time horizons undervalue wind by imposing exogenous limits on growth. This thesis fills a critical gap in the literature by taking a closer look at the cost and environmental impacts of large-scale wind. Estimates of the average cost of wind generation---now roughly 4¢/kWh---do not address the cons arising from the spatial distribution and intermittency of wind. This thesis develops a theoretical framework for assessing the intermittency cost of wind. In addition, an economic characterization of a wind system is provided in which long-distance electricity transmission, storage, and gas turbines are used to supplement variable wind power output to meet a time-varying load. With somewhat optimistic assumptions about the cost of wind turbines, the use of wind to serve 50% of demand adds ˜1--2¢/kWh to the cost of electricity, a cost comparable to that of other large-scale low carbon technologies. This thesis also explores the environmental impacts posed by large-scale wind. Though avian mortality and noise caused controversy in the early years of wind development, improved technology and exhaustive siting assessments have minimized their impact. The aesthetic valuation of wind farms can be improved significantly with better design, siting, construction, and maintenance procedures, but opposition may

Trends in Wind Energy Technology Development

DEFF Research Database (Denmark)

Rasmussen, Flemming; Madsen, Peter Hauge; Tande, John O.

2011-01-01

. The huge potential of wind, the rapid development of the technology and the impressive growth of the industry justify the perception that wind energy is changing its role to become the future backbone of a secure global energy supply. Between the mid-1980s, when the wind industry took off, and 2005 wind......Text Over the past 25 years global wind energy capacity has doubled every three years, corresponding to a tenfold expansion every decade. By the end of 2010 global installed wind capacity was approximately 200 GW and in 2011 is expected to produce about 2% of global electricity consumption...... turbine technology has seen rapid development, leading to impressive increases in the size of turbines, with corresponding cost reductions. From 2005 to 2009 the industry’s focus seems to have been on increasing manufacturing capacity, meeting market demand and making wind turbines more reliable...

Superconductivity for Large Scale Wind Turbines

Energy Technology Data Exchange (ETDEWEB)

R. Fair; W. Stautner; M. Douglass; R. Rajput-Ghoshal; M. Moscinski; P. Riley; D. Wagner; J. Kim; S. Hou; F. Lopez; K. Haran; J. Bray; T. Laskaris; J. Rochford; R. Duckworth

2012-10-12

A conceptual design has been completed for a 10MW superconducting direct drive wind turbine generator employing low temperature superconductors for the field winding. Key technology building blocks from the GE Wind and GE Healthcare businesses have been transferred across to the design of this concept machine. Wherever possible, conventional technology and production techniques have been used in order to support the case for commercialization of such a machine. Appendices A and B provide further details of the layout of the machine and the complete specification table for the concept design. Phase 1 of the program has allowed us to understand the trade-offs between the various sub-systems of such a generator and its integration with a wind turbine. A Failure Modes and Effects Analysis (FMEA) and a Technology Readiness Level (TRL) analysis have been completed resulting in the identification of high risk components within the design. The design has been analyzed from a commercial and economic point of view and Cost of Energy (COE) calculations have been carried out with the potential to reduce COE by up to 18% when compared with a permanent magnet direct drive 5MW baseline machine, resulting in a potential COE of 0.075 $/kWh. Finally, a top-level commercialization plan has been proposed to enable this technology to be transitioned to full volume production. The main body of this report will present the design processes employed and the main findings and conclusions.

Research on large-scale wind farm modeling

Science.gov (United States)

Ma, Longfei; Zhang, Baoqun; Gong, Cheng; Jiao, Ran; Shi, Rui; Chi, Zhongjun; Ding, Yifeng

2017-01-01

Due to intermittent and adulatory properties of wind energy, when large-scale wind farm connected to the grid, it will have much impact on the power system, which is different from traditional power plants. Therefore it is necessary to establish an effective wind farm model to simulate and analyze the influence wind farms have on the grid as well as the transient characteristics of the wind turbines when the grid is at fault. However we must first establish an effective WTGs model. As the doubly-fed VSCF wind turbine has become the mainstream wind turbine model currently, this article first investigates the research progress of doubly-fed VSCF wind turbine, and then describes the detailed building process of the model. After that investigating the common wind farm modeling methods and pointing out the problems encountered. As WAMS is widely used in the power system, which makes online parameter identification of the wind farm model based on off-output characteristics of wind farm be possible, with a focus on interpretation of the new idea of identification-based modeling of large wind farms, which can be realized by two concrete methods.

Technological learning in offshore wind energy: Different roles of the government

International Nuclear Information System (INIS)

Smit, Thijs; Junginger, Martin; Smits, Ruud

2007-01-01

Offshore wind energy is a promising source of renewable electricity, even though its current costs prevent large-scale implementation. Technological learning has improved the technology and its economic performance already, and could result in significant further improvements. This study investigates how technological learning takes place in offshore wind energy and how technological learning is related to different policy regimes. Offshore wind energy developments in Denmark and the United Kingdom have been analysed with a technology-specific innovation systems approach. The results reveal that the dominant forms of learning are learning by doing and learning by using. At the same time, learning by interacting is crucial to achieve the necessary binding elements in the technology-specific innovation system. Generally, most learning processes were performed by self-organizing entities. However, sometimes cultural and technical barriers occurred, excluding component suppliers and knowledge institutes from the innovation system. Danish policies successfully anticipated these barriers and removed them; therefore, the Danish policies can be characterized as pro-active. British policies shaped stable conditions for learning only; therefore, they can be characterized as active. In the future, barriers could hinder learning by interacting between the oil and gas industry, the offshore wind industry and academia. Based on this study, we suggest national and international policy makers to design long-term policies to anticipate these barriers, in order to contribute to technological learning

Variability in large-scale wind power generation: Variability in large-scale wind power generation

Energy Technology Data Exchange (ETDEWEB)

Kiviluoma, Juha [VTT Technical Research Centre of Finland, Espoo Finland; Holttinen, Hannele [VTT Technical Research Centre of Finland, Espoo Finland; Weir, David [Energy Department, Norwegian Water Resources and Energy Directorate, Oslo Norway; Scharff, Richard [KTH Royal Institute of Technology, Electric Power Systems, Stockholm Sweden; Söder, Lennart [Royal Institute of Technology, Electric Power Systems, Stockholm Sweden; Menemenlis, Nickie [Institut de recherche Hydro-Québec, Montreal Canada; Cutululis, Nicolaos A. [DTU, Wind Energy, Roskilde Denmark; Danti Lopez, Irene [Electricity Research Centre, University College Dublin, Dublin Ireland; Lannoye, Eamonn [Electric Power Research Institute, Palo Alto California USA; Estanqueiro, Ana [LNEG, Laboratorio Nacional de Energia e Geologia, UESEO, Lisbon Spain; Gomez-Lazaro, Emilio [Renewable Energy Research Institute and DIEEAC/EDII-AB, Castilla-La Mancha University, Albacete Spain; Zhang, Qin [State Grid Corporation of China, Beijing China; Bai, Jianhua [State Grid Energy Research Institute Beijing, Beijing China; Wan, Yih-Huei [National Renewable Energy Laboratory, Transmission and Grid Integration Group, Golden Colorado USA; Milligan, Michael [National Renewable Energy Laboratory, Transmission and Grid Integration Group, Golden Colorado USA

2015-10-25

The paper demonstrates the characteristics of wind power variability and net load variability in multiple power systems based on real data from multiple years. Demonstrated characteristics include probability distribution for different ramp durations, seasonal and diurnal variability and low net load events. The comparison shows regions with low variability (Sweden, Spain and Germany), medium variability (Portugal, Ireland, Finland and Denmark) and regions with higher variability (Quebec, Bonneville Power Administration and Electric Reliability Council of Texas in North America; Gansu, Jilin and Liaoning in China; and Norway and offshore wind power in Denmark). For regions with low variability, the maximum 1 h wind ramps are below 10% of nominal capacity, and for regions with high variability, they may be close to 30%. Wind power variability is mainly explained by the extent of geographical spread, but also higher capacity factor causes higher variability. It was also shown how wind power ramps are autocorrelated and dependent on the operating output level. When wind power was concentrated in smaller area, there were outliers with high changes in wind output, which were not present in large areas with well-dispersed wind power.

Wind Energy Conversion Systems Technology and Trends

CERN Document Server

2012-01-01

Wind Energy Conversion System covers the technological progress of wind energy conversion systems, along with potential future trends. It includes recently developed wind energy conversion systems such as multi-converter operation of variable-speed wind generators, lightning protection schemes, voltage flicker mitigation and prediction schemes for advanced control of wind generators. Modeling and control strategies of variable speed wind generators are discussed, together with the frequency converter topologies suitable for grid integration. Wind Energy Conversion System also describes offshore farm technologies including multi-terminal topology and space-based wind observation schemes, as well as both AC and DC based wind farm topologies. The stability and reliability of wind farms are discussed, and grid integration issues are examined in the context of the most recent industry guidelines. Wind power smoothing, one of the big challenges for transmission system operators, is a particular focus. Fault ride th...

Airfoil family design for large offshore wind turbine blades

Science.gov (United States)

Méndez, B.; Munduate, X.; San Miguel, U.

2014-06-01

Wind turbine blades size has scaled-up during last years due to wind turbine platform increase especially for offshore applications. The EOLIA project 2007-2010 (Spanish Goverment funded project) was focused on the design of large offshore wind turbines for deep waters. The project was managed by ACCIONA Energia and the wind turbine technology was designed by ACCIONA Windpower. The project included the design of a wind turbine airfoil family especially conceived for large offshore wind turbine blades, in the order of 5MW machine. Large offshore wind turbines suffer high extreme loads due to their size, in addition the lack of noise restrictions allow higher tip speeds. Consequently, the airfoils presented in this work are designed for high Reynolds numbers with the main goal of reducing blade loads and mantainig power production. The new airfoil family was designed in collaboration with CENER (Spanish National Renewable Energy Centre). The airfoil family was designed using a evolutionary algorithm based optimization tool with different objectives, both aerodynamic and structural, coupled with an airfoil geometry generation tool. Force coefficients of the designed airfoil were obtained using the panel code XFOIL in which the boundary layer/inviscid flow coupling is ineracted via surface transpiration model. The desing methodology includes a novel technique to define the objective functions based on normalizing the functions using weight parameters created from data of airfoils used as reference. Four airfoils have been designed, here three of them will be presented, with relative thickness of 18%, 21%, 25%, which have been verified with the in-house CFD code, Wind Multi Block WMB, and later validated with wind tunnel experiments. Some of the objectives for the designed airfoils concern the aerodynamic behavior (high efficiency and lift, high tangential coefficient, insensitivity to rough conditions, etc.), others concern the geometry (good for structural design

Airfoil family design for large offshore wind turbine blades

International Nuclear Information System (INIS)

Méndez, B; Munduate, X; Miguel, U San

2014-01-01

Wind turbine blades size has scaled-up during last years due to wind turbine platform increase especially for offshore applications. The EOLIA project 2007-2010 (Spanish Goverment funded project) was focused on the design of large offshore wind turbines for deep waters. The project was managed by ACCIONA Energia and the wind turbine technology was designed by ACCIONA Windpower. The project included the design of a wind turbine airfoil family especially conceived for large offshore wind turbine blades, in the order of 5MW machine. Large offshore wind turbines suffer high extreme loads due to their size, in addition the lack of noise restrictions allow higher tip speeds. Consequently, the airfoils presented in this work are designed for high Reynolds numbers with the main goal of reducing blade loads and mantainig power production. The new airfoil family was designed in collaboration with CENER (Spanish National Renewable Energy Centre). The airfoil family was designed using a evolutionary algorithm based optimization tool with different objectives, both aerodynamic and structural, coupled with an airfoil geometry generation tool. Force coefficients of the designed airfoil were obtained using the panel code XFOIL in which the boundary layer/inviscid flow coupling is ineracted via surface transpiration model. The desing methodology includes a novel technique to define the objective functions based on normalizing the functions using weight parameters created from data of airfoils used as reference. Four airfoils have been designed, here three of them will be presented, with relative thickness of 18%, 21%, 25%, which have been verified with the in-house CFD code, Wind Multi Block WMB, and later validated with wind tunnel experiments. Some of the objectives for the designed airfoils concern the aerodynamic behavior (high efficiency and lift, high tangential coefficient, insensitivity to rough conditions, etc.), others concern the geometry (good for structural design

Manufacturing and service opportunities for Canadian companies in large wind turbines

International Nuclear Information System (INIS)

Wittholz, H.; Lacroix, A.

2003-04-01

This report presents an overview of the wind power industry and recommends initiatives for Canadian companies to embark in an industry with promising growth opportunities. Wind energy is the fastest growing source of energy with many associated manufacturing and service opportunities and employment benefits. In 2001, the wind energy industry invested US$5.2 billion worldwide. The average size of a large wind turbine is approximately 1.0 MW for on-shore sites and 2 to 5 MW for offshore applications. The technology is dominated by European companies, with the top 10 turbine manufacturers supplying more than 90 per cent of the global market. This report investigates the risks and opportunities available for Canada in the service and manufacturing sectors of the wind energy industry. In addition, 17 wind turbine components and subsystems in mechanical and electrical parts are described. It was suggested that, given the technology that is currently available in Canada, the greatest manufacturing opportunities lie in the development of rotor blades, towers, base frames, vibration mounts and generators. The report also defines market entry barriers and presents solutions. It was emphasized that timing to the market is critical because it will be more difficult to enter the competitive market in the coming years. The author suggests a target of 20 per cent of North American wind energy market for Canadian companies by 2020, equivalent to US$2.68 billion in annual sales and 58,800 jobs. 6 refs., 6 tabs., 1 fig

2014 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Daghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoen, Ben [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hamachi LaCommare, Kristina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Millstein, Dev [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hansen, Dana [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Porter, Kevin [Exeter Associates, Columbia, MD (United States); Widiss, Rebecca [Exeter Associates, Columbia, MD (United States); Buckley, Michael [Exeter Associates, Columbia, MD (United States); Oteri, Frank [National Renewable Energy Lab. (NREL), Golden, CO (United States); Smith, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tegen, Suzanne [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-08-06

Wind power capacity additions in the United States rebounded in 2014, and continued growth through 2016 is anticipated. Recent and projected near-term growth is supported by the industry’s primary federal incentive—the production tax credit (PTC)—which is available for projects that began construction by the end of 2014. Wind additions are also being driven by recent improvements in the cost and performance of wind power technologies, which have resulted in the lowest power sales prices ever seen in the U.S. wind sector. Growing corporate demand for wind energy and state-level policies play important roles as well. Expectations for continued technological advancements and cost reductions may further boost future growth. At the same time, the prospects for growth beyond 2016 are uncertain. The PTC has expired, and its renewal remains in question. Continued low natural gas prices, modest electricity demand growth, and limited near-term demand from state renewables portfolio standards (RPS) have also put a damper on growth expectations. These trends, in combination with increasingly global supply chains, have limited the growth of domestic manufacturing of wind equipment. What they mean for wind power additions through the end of the decade and beyond will be dictated in part by future natural gas prices, fossil plant retirements, and policy decisions.

A probabilistic assessment of large scale wind power development for long-term energy resource planning

Science.gov (United States)

Kennedy, Scott Warren

A steady decline in the cost of wind turbines and increased experience in their successful operation have brought this technology to the forefront of viable alternatives for large-scale power generation. Methodologies for understanding the costs and benefits of large-scale wind power development, however, are currently limited. In this thesis, a new and widely applicable technique for estimating the social benefit of large-scale wind power production is presented. The social benefit is based upon wind power's energy and capacity services and the avoidance of environmental damages. The approach uses probabilistic modeling techniques to account for the stochastic interaction between wind power availability, electricity demand, and conventional generator dispatch. A method for including the spatial smoothing effect of geographically dispersed wind farms is also introduced. The model has been used to analyze potential offshore wind power development to the south of Long Island, NY. If natural gas combined cycle (NGCC) and integrated gasifier combined cycle (IGCC) are the alternative generation sources, wind power exhibits a negative social benefit due to its high capacity cost and the relatively low emissions of these advanced fossil-fuel technologies. Environmental benefits increase significantly if charges for CO2 emissions are included. Results also reveal a diminishing social benefit as wind power penetration increases. The dependence of wind power benefits on natural gas and coal prices is also discussed. In power systems with a high penetration of wind generated electricity, the intermittent availability of wind power may influence hourly spot prices. A price responsive electricity demand model is introduced that shows a small increase in wind power value when consumers react to hourly spot prices. The effectiveness of this mechanism depends heavily on estimates of the own- and cross-price elasticities of aggregate electricity demand. This work makes a valuable

Great expectations: large wind turbines

International Nuclear Information System (INIS)

De Vries, E.

2001-01-01

This article focuses on wind turbine product development, and traces the background to wind turbines from the first generation 1.5 MW machines in 1995-6, plans for the second generation 3-5 MW class turbines to meet the expected boom in offshore wind projects, to the anticipated installation of a 4.5 MW turbine, and offshore wind projects planned for 2000-2002. The switch by the market leader Vestas to variable speed operation in 2000, the new product development and marketing strategy taken by the German Pro + Pro consultancy in their design of a 1.5 MW variable speed pitch control concept, the possible limiting of the size of turbines due to logistical difficulties, opportunities offered by air ships for large turbines, and the commissioning of offshore wind farms are discussed. Details of some 2-5 MW offshore wind turbine design specifications are tabulated

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)

Market penetration of large wind/diesel systems

International Nuclear Information System (INIS)

Kronborg, T.

1992-01-01

Burmeister ampersand Wain is developing a large size wind/diesel package in collaboration with Micon, the Danish wind turbine manufacturer, and the Danish utility NESA. The package comprises an initial calculation of the technical feasibility and the economic viability of an actual project, installing the optimum number of large wind turbines, and service, operation, and maintenance as needed. The concept should be seen as an addition to existing diesel-based power stations. Wind turbines are especially advantageous in smaller diesel-based electrical systems in the 1-20 MW range because such systems can have high fuel costs and expensive maintenance. Analysis of the market for the wind/diesel concept indicates islands and remote areas with limited population are likely candidates for implementation of wind/diesel systems. An example of an economic analysis of a wind/diesel application on an isolated island is presented, showing the cost savings possible. To obtain practical experience and to demonstrate the wind/diesel concept, a MW-size demonstration plant is being constructed in Denmark

Marketing Strategic Choices for Wind Technology in China : case: Chinese Domestic Wind Technology Companies

OpenAIRE

Shi, Yi

2011-01-01

There are almost 80 wind turbine manufacturers in China. However, the supportive government policies are the fact behind the rapid growth of those case companies. In reality, there are less than 10 Chinese wind turbine manufacturers with actual production capacity. Most of them lack core technology and depend in many ways on state patronage. The current situation is worrisome. Therefore, the correct comprehension of wind power market conditions and the consequent adoption of right marketing s...

2016 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-08-08

Wind power capacity in the United States experienced strong growth in 2016. Recent and projected near-term growth is supported by the industry’s primary federal incentive—the production tax credit (PTC)—as well as a myriad of state-level policies. Wind additions have also been driven by improvements in the cost and performance of wind power technologies, yielding low power sales prices for utility, corporate, and other purchasers.

Wind turbine technology principles and design

CERN Document Server

Adaramola, Muyiwa

2014-01-01

IntroductionPart I: AerodynamicsWind Turbine Blade Design; Peter J. Schubel and Richard J. CrossleyA Shrouded Wind Turbine Generating High Output Power with Wind-Lens Technology; Yuji Ohya and Takashi KarasudaniEcomoulding of Composite Wind Turbine Blades Using Green Manufacturing RTM Process; Brahim AttafAerodynamic Shape Optimization of a Vertical-Axis Wind Turbine Using Differential Evolution; Travis J. Carrigan, Brian H. Dennis, Zhen X. Han, and Bo P. WangPart II: Generators and Gear Systems

Conceptual design and costs of large wind turbines

International Nuclear Information System (INIS)

Hau, E.; Harrison, R.; Cockerill, T.T.; Snel, H.

1996-01-01

The development of large wind turbines, with capacities in excess of 1 MW is reviewed. Despite statistical evidence to the contrary, there are some reasons to be optimistic that further development will render large machines economic for commercial uses. The direction in which such development should proceed is unclear, however. A cost model, founded on the principles of conceptual design, with the objective of evaluating large wind turbine design options is described. Use of the model allows conclusions to be drawn regarding the potential for development of certain large wind turbine configurations. (author)

Wind Resource Assessment – Østerild National Test Centre for Large Wind Turbines

OpenAIRE

Hansen, Brian Ohrbeck; Courtney, Michael; Mortensen, Niels Gylling

2014-01-01

This report presents a wind resource assessment for the seven test stands at the Østerild National Test Centre for Large Wind Turbines in Denmark. Calculations have been carried out mainly using wind data from three on-site wind lidars. The generalized wind climates applied in the wind resource calculations for the seven test stands are based on correlations between a short period of on-site wind data from the wind lidars with a long-term reference. The wind resource assessment for the seven ...

Field measurement of wind pressure and wind-induced vibration of large-span spatial cable-truss system under strong wind or typhoon

Directory of Open Access Journals (Sweden)

ZHANG Zhihong

2013-10-01

Full Text Available In order to ensure wind-resistance safety of large-span pre-stressed flexible system in southeast coast area of China,and to prepare something for revising of current codes of practice or technical standards,the present paper conducts field measurement of wind pressure and wind-induced vibration of a practical and typical large-span spatial cable-truss system-lunar stadium in Yueqing city.Wind loading and wind effects on full-scale structure under strong wind or typhoon in real architectural environment can be obtained directly and effectively.Field measurement is the best way to investigate the wind loading property,wind effects,and wind-structure interactions of large-span flexible system.Measured data will be highly valuable for scientific research and practical design.On the other hand,it also provides the basis of wind-resistance safety design of this kind of tension structures.If any creative development,it would dramatically improve the research level of large-span pre-stressed flexible system in our country.

Global wind power potential: Physical and technological limits

International Nuclear Information System (INIS)

Castro, Carlos de; Mediavilla, Margarita; Miguel, Luis Javier; Frechoso, Fernando

2011-01-01

This paper is focused on a new methodology for the global assessment of wind power potential. Most of the previous works on the global assessment of the technological potential of wind power have used bottom-up methodologies (e.g. ). Economic, ecological and other assessments have been developed, based on these technological capacities. However, this paper tries to show that the reported regional and global technological potential are flawed because they do not conserve the energetic balance on Earth, violating the first principle of energy conservation (). We propose a top-down approach, such as that in , to evaluate the physical-geographical potential and, for the first time, to evaluate the global technological wind power potential, while acknowledging energy conservation. The results give roughly 1 TW for the top limit of the future electrical potential of wind energy. This value is much lower than previous estimates and even lower than economic and realizable potentials published for the mid-century (e.g. ). - Highlights: → Reported wind power potentials are flawed because they violate energy conservation. → For the first time, it is evaluated the technological wind power potential with a top-down approach. → Our results show 1 TWe for the limit of wind power energy, which is much lower than previous estimates.

2015 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoen, Ben [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rand, Joe [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Millstein, Dev [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Porter, Kevin [Exeter Associates, Columbia, MD (United States); Widiss, Rebecca [Exeter Associates, Columbia, MD (United States); Oteri, Frank [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tegen, Suzanne [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tian, Tian [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-08-01

This annual report--now in its tenth year--provides a detailed overview of developments and trends in the U.S. wind power market, with a particular focus on 2015. The report begins with an overview of key installation trends and then covers an array of industry and technology trends. The report also discusses project performance, wind turbine prices, project costs, operations and maintenance expenses, and prices paid for wind power in the United States. The report examines policy and market factors impacting the domestic wind power market and provides a preview of possible near-term market developments, expenses, and prices paid for wind power in the United States. The report examines policy and market factors impacting the domestic wind power market and provides a preview of possible near-term market developments.

Operation and control of large wind turbines and wind farms

Energy Technology Data Exchange (ETDEWEB)

Soerensen, Poul; Hansen, Anca D.; Thomsen, Kenneth (and others)

2005-09-01

This report is the final report of a Danish research project 'Operation and control of large wind turbines and wind farms'. The objective of the project has been to analyse and assess operational strategies and possibilities for control of different types of wind turbines and different wind farm concepts. The potentials of optimising the lifetime/energy production ratio by means of using revised operational strategies for the individual wind turbines are investigated. Different strategies have been simulated, where the power production is decreased to an optimum when taking loads and actual price of produced electricity into account. Dynamic models and control strategies for the wind farms have also been developed, with the aim to optimise the operation of the wind farms considering participation in power system control of power (frequency) and reactive power (voltage), maximise power production, keep good power quality and limit mechanical loads and life time consumption. The project developed models for 3 different concepts for wind farms. Two of the concepts use active stall controlled wind turbines, one with AC connection and one with modern HVDC/VSC connection of the wind farm. The third concept is based on pitch controlled wind turbines using doubly fed induction generators. The models were applied to simulate the behaviour of the wind farm control when they were connected to a strong grid, and some initial simulations were performed to study the behaviour of the wind farms when it was isolated from the main grid on a local grid. Also the possibility to use the available information from the wind turbine controllers to predict the wind speed has been investigated. The main idea has been to predict the wind speed at a wind turbine using up-wind measurements of the wind speed in another wind turbine. (au)

2016 Offshore Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Musial, Walter; Beiter, Philipp; Schwabe, Paul; Tian, Tian; Stehly, Tyler; Spitsen, Paul; Robertson, Amy; Gevorgian, Vahan

2017-08-08

The 2016 Offshore Wind Technologies Market Report was developed by the National Renewable Energy Laboratory (NREL) for the U.S. Department of Energy (DOE) and is intended to provide offshore wind policymakers, regulators, developers, researchers, engineers, financiers, and supply chain participants, with quantitative information about the offshore wind market, technology, and cost trends in the United States and worldwide. In particular, this report is intended to provide detailed information on the domestic offshore wind industry to provide context to help navigate technical and market barriers and opportunities. The scope of the report covers the status of the 111 operating offshore wind projects in the global fleet through December 31, 2016, and provides the status and analysis on a broader pipeline of 593 projects at some stage of development. In addition, this report provides a wider assessment of domestic developments and events through the second quarter of 2017 to provide a more up-to-date discussion of this dynamically evolving industry.

Marketing strategic choice for wind power technology in China : case: Chinese domestic wind technology companies

OpenAIRE

Shi, Yi

2011-01-01

There are almost 80 wind turbine manufacturers in China. However, the supportive government policies are the fact behind the rapid growth of those case companies. In reality, there are less than 10 Chinese wind turbine manufacturers with actual production capacity. Most of them lack core technology and depend in many ways on state patronage. The current situation is worrisome. Therefore, the correct comprehension of wind power market conditions and the consequent adoption of right marketing s...

Enhancing information for solar and wind energy technology deployment in Brazil

Energy Technology Data Exchange (ETDEWEB)

Ramos Martins, Fernando, E-mail: fernando.martins@inpe.br [Centro de Ciencia do Sistema Terrestre-Instituto Nacisonal de Pesquisas Espaciais (Earth System Center-National Institute for Space Research), P.O. Box 515, 12245-970, Sao Jose dos Campos (Brazil); Pereira, Enio Bueno, E-mail: enio.pereira@inpe.br [Centro de Ciencia do Sistema Terrestre-Instituto Nacisonal de Pesquisas Espaciais (Earth System Center-National Institute for Space Research), P.O. Box 515, 12245-970, Sao Jose dos Campos (Brazil)

2011-07-15

Brazil's primary energy matrix is based on more than 47% of renewables, and more than 85% of its electricity is generated by hydro power sources. Despite this large fraction of renewable energy resources, less than 0.3% of the national energy supply comes from solar or wind sources. This paper presents a diagnostic review on the penetration of the solar and wind energy technologies in Brazil. It also includes a survey of the latest government policies and incentives for renewable energies deployment by entrepreneurs, industry and commercial and residential consumers. In addition, the paper analyses how to best meet the requirements for policy support and information technology to boost the deployment of solar technology and wind energy in Brazil. This study was mostly based on results of a widely distributed survey covering key issues, and also by personal interviews carried out with key stakeholders in order to better understand the issues highlighted in the survey responses. The study pointed out some of the main obstacles to effectively promote and improve government policies and actions for investment in solar and wind energy market in Brazil. - Highlights: > Current status on the solar and wind energy deployment in Brazil is presented. > Policy framework required to support solar and wind energy was discussed. > Study was based on responses for consultations with key stakeholders. > Worthiness Index was established to rank the stakeholders outlooks. > Energy price, human resources and tax reductions were indicated as priority.

Enhancing information for solar and wind energy technology deployment in Brazil

International Nuclear Information System (INIS)

Ramos Martins, Fernando; Pereira, Enio Bueno

2011-01-01

Brazil's primary energy matrix is based on more than 47% of renewables, and more than 85% of its electricity is generated by hydro power sources. Despite this large fraction of renewable energy resources, less than 0.3% of the national energy supply comes from solar or wind sources. This paper presents a diagnostic review on the penetration of the solar and wind energy technologies in Brazil. It also includes a survey of the latest government policies and incentives for renewable energies deployment by entrepreneurs, industry and commercial and residential consumers. In addition, the paper analyses how to best meet the requirements for policy support and information technology to boost the deployment of solar technology and wind energy in Brazil. This study was mostly based on results of a widely distributed survey covering key issues, and also by personal interviews carried out with key stakeholders in order to better understand the issues highlighted in the survey responses. The study pointed out some of the main obstacles to effectively promote and improve government policies and actions for investment in solar and wind energy market in Brazil. - Highlights: → Current status on the solar and wind energy deployment in Brazil is presented. → Policy framework required to support solar and wind energy was discussed. → Study was based on responses for consultations with key stakeholders. → Worthiness Index was established to rank the stakeholders outlooks. → Energy price, human resources and tax reductions were indicated as priority.

A study of rotor and platform design trade-offs for large-scale floating vertical axis wind turbines

Science.gov (United States)

Griffith, D. Todd; Paquette, Joshua; Barone, Matthew; Goupee, Andrew J.; Fowler, Matthew J.; Bull, Diana; Owens, Brian

2016-09-01

Vertical axis wind turbines are receiving significant attention for offshore siting. In general, offshore wind offers proximity to large populations centers, a vast & more consistent wind resource, and a scale-up opportunity, to name a few beneficial characteristics. On the other hand, offshore wind suffers from high levelized cost of energy (LCOE) and in particular high balance of system (BoS) costs owing to accessibility challenges and limited project experience. To address these challenges associated with offshore wind, Sandia National Laboratories is researching large-scale (MW class) offshore floating vertical axis wind turbines (VAWTs). The motivation for this work is that floating VAWTs are a potential transformative technology solution to reduce offshore wind LCOE in deep-water locations. This paper explores performance and cost trade-offs within the design space for floating VAWTs between the configurations for the rotor and platform.

Mars Technologies Spawn Durable Wind Turbines

Science.gov (United States)

Bubenheim, David L.

2013-01-01

Sometimes referred to as regenerative life support systems, the concept includes an enclosed self-sufficient habitat that can independently support life for years on end. Such a system aims not only to produce its own food and water but to purify air and convert waste into useful byproducts. In the early 1990s, NASA was planning for an extended stay on Mars, and Bubenheim and his Ames colleagues were concentrating efforts on creating a complete ecological system to sustain human crewmembers during their time on the Red Planet. The main barrier to developing such a system, he says, is energy. Mars has no power plants, and a regenerative system requires equipment that runs on electricity to do everything from regulating humidity in the atmosphere to monitoring the quality of recycled water. The Ames group started looking at how to best make power on a planet that is millions of miles away from Earth and turned to a hybrid concept combining wind and solar power technologies. The reason was that Mars experiences frequent dust storms that can block nearly all sunlight. When theres a dust storm and the wind is blowing, the wind system could be the dominant power source. When the wind is not blowing and the sun is out, photovoltaics could be the dominant source, says Bubenheim.To develop and test the wind power technology, Ames turned to a remote, harsh environment here on Earth: the South Pole. The South Pole was a really good analog for Mars, says Bubenheim. The technology features for going to Mars were the same technology features needed to make something work at the South Pole.Around the same time that NASA started investigating energy technologies for the Red Planet, the National Science Foundation (NSF) was working on a redesign of their station at the South Pole. To power its operations, NSF used fuel that it flew to the remote location, but the Foundation recognized the benefits of also using onsite renewable energy technologies. In the winter they have small

Applied wind energy research at the National Wind Technology Center

International Nuclear Information System (INIS)

Robinson, M.C.; Tu, P.

1997-01-01

Applied research activities currently being undertaken at the National Wind Technology Center, part of the National Renewable Energy Laboratory, in the United States, are divided into several technical disciplines. An integrated multi-disciplinary approach is urged for the future in order to evaluate advanced turbine designs. The risk associated with any new turbine development program can thus be mitigated through the provision of the advanced technology, analysis tools and innovative designs available at the Center, and wind power can be promoted as a viable renewable energy alternative. (UK)

Trends, Opportunities, and Challenges for Tall Wind Turbine and Tower Technologies

Energy Technology Data Exchange (ETDEWEB)

Lantz, Eric; Roberts, Owen; Dykes, Katherine

2017-06-28

This presentation summarizes recent analysis focused on characterizing the opportunity for Tall Wind technologies generally and for tall tower technologies specifically. It seeks to illuminate and explain the concept of Tall Wind, its impact on the wind industry to date, and the potential value of Tall Wind in the future. It also explores the conditions and locations under which the impacts of Tall Wind offer the most significant potential to increase wind technology performance. In addition, it seeks to examine the status of tall tower technology as a key sub-component of Tall Wind, focusing on the potential for continued innovation in tubular steel wind turbine towers and the status and potential for a select set of alternative tall tower technologies.

Configuration study of large wind parks

Energy Technology Data Exchange (ETDEWEB)

Lundberg, Stefan

2003-07-01

In this thesis, layouts of various large-scale wind parks, using both AC as well as DC, are investigated. Loss modelling of the wind park components as well as calculations of the energy capture of the turbines using various electrical systems are performed, and the energy production cost of the various park configurations is determined. The most interesting candidate for a DC transmission based wind park was investigated more in detail, the series DC wind park. Finally, the power quality impact in the PCC (point of common coupling) was studied. It was found that from an energy capture point of view, the difference in energy production between various wind turbine systems is very small. Of all the investigated wind park configurations, the wind park with the series connected DC wind turbines seems to have the best potential to give the lowest energy production cost, if the transmission distance is longer then 10-20 km. Regarding the series DC wind park it was found that it is the most difficult one to control. However, a control algorithm for the series park and its turbines was derived and successfully tested. Still, several more details regarding the control of the series wind park has to be dealt with.

Dysprosium, the balance problem, and wind power technology

International Nuclear Information System (INIS)

Elshkaki, Ayman; Graedel, T.E.

2014-01-01

Highlights: • We investigate the impacts of the increasing market share of wind power on the demand and supply of REE. • The analysis is carried out using a dynamic material flow and stock model and three scenarios for Dy supply. • The supply of Dy from all deposits will likely lead to an oversupply of the total REEs, Nd, La, Ce and Y. • The supply of Dy from critical REE or Dy rich deposits will likely lead to an oversupply of Ce and Y only. • Large quantities of thorium will be co-produced as a result of Dy demand that needs to be managed carefully. - Abstract: Wind power technology is one of the cleanest electricity generation technologies that are expected to have a substantial share in the future electricity mix. Nonetheless, the expected increase in the market share of wind technology has led to an increasing concern of the availability, production capacity and geographical concentration of the metals required for the technology, especially the rear earth elements (REE) neodymium (Nd) and the far less abundant dysprosium (Dy), and the impacts associated with their production. Moreover, Nd and Dy are coproduced with other rare earth metals mainly from iron, titanium, zirconium, and thorium deposits. Consequently, an increase in the demand for Nd and Dy in wind power technology and in their traditional applications may lead to an increase in the production of the host metals and other companion REE, with possible implications on their supply and demand. In this regard, we have used a dynamic material flow and stock model to study the impacts of the increasing demand for Nd and Dy on the supply and demand of the host metals and other companion REE. In one scenario, when the supply of Dy is covered by all current and expected producing deposits, the increase in the demand for Dy leads to an oversupply of 255 Gg of total REE and an oversupply of the coproduced REE Nd, La, Ce and Y. In the second and third scenarios, however, when the supply of Dy is

Vibration monitoring of large generator stator and-winding

International Nuclear Information System (INIS)

Duffeau, F.; Bernard, P.

1999-01-01

Large generators of French Nuclear Power plants are equipped with a standardised vibration monitoring system. The first aim of these new systems is to protect the machines by generating alarms in the control room when predefined vibration thresholds have been over-passed. Secondly, this specially designed instrumentation permits to create a National data base allowing to compare different generators of the same technology. Additionally, statistical methods have been developed in order to 'guess' vibration level at several locations of the stator end-windings, depending on the actual operating parameters of the generator, i.e. reactive and active power load. So this paper presents the general concept of the vibration monitoring of EDF large generator stators and deals with a new method to predict vibrations in different locations under control. (authors)

Wind Energy Workforce Development: Engineering, Science, & Technology

Energy Technology Data Exchange (ETDEWEB)

Lesieutre, George A.; Stewart, Susan W.; Bridgen, Marc

2013-03-29

Broadly, this project involved the development and delivery of a new curriculum in wind energy engineering at the Pennsylvania State University; this includes enhancement of the Renewable Energy program at the Pennsylvania College of Technology. The new curricula at Penn State includes addition of wind energy-focused material in more than five existing courses in aerospace engineering, mechanical engineering, engineering science and mechanics and energy engineering, as well as three new online graduate courses. The online graduate courses represent a stand-alone Graduate Certificate in Wind Energy, and provide the core of a Wind Energy Option in an online intercollege professional Masters degree in Renewable Energy and Sustainability Systems. The Pennsylvania College of Technology erected a 10 kilowatt Xzeres wind turbine that is dedicated to educating the renewable energy workforce. The entire construction process was incorporated into the Renewable Energy A.A.S. degree program, the Building Science and Sustainable Design B.S. program, and other construction-related coursework throughout the School of Construction and Design Technologies. Follow-on outcomes include additional non-credit opportunities as well as secondary school career readiness events, community outreach activities, and public awareness postings.

2015 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Electricity Markets and Policy Group; Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Electricity Markets and Policy Group; Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoen, Ben [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rand, Joe [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Millstein, Dev [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Porter, Kevin [Exeter Associates, Columbia, MD (United States); Widiss, Rebecca [Exeter Associates, Columbia, MD (United States); Oteri, Frank [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tegen, Suzanne [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tian, Tian [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-08-03

Annual wind power capacity additions in the United States surged in 2015 and are projected to continue at a rapid clip in the coming five years. Recent and projected near-term growth is supported by the industry’s primary federal incentive—the production tax credit (PTC)—having been extended for several years (though with a phase-down schedule, described further on pages 68-69), as well as a myriad of state-level policies. Wind additions are also being driven by improvements in the cost and performance of wind power technologies, yielding low power sales prices for utility, corporate, and other purchasers. At the same time, the prospects for growth beyond the current PTC cycle remain uncertain: growth could be blunted by declining federal tax support, expectations for low natural gas prices, and modest electricity demand growth. This annual report—now in its tenth year—provides a detailed overview of developments and trends in the U.S. wind power market, with a particular focus on 2015. The report begins with an overview of key installation-related trends: trends in U.S. wind power capacity growth; how that growth compares to other countries and generation sources; the amount and percentage of wind energy in individual states; the status of offshore wind power development; and the quantity of proposed wind power capacity in various interconnection queues in the United States. Next, the report covers an array of wind power industry trends: developments in turbine manufacturer market share; manufacturing and supply-chain developments; wind turbine and component imports into and exports from the United States; project financing developments; and trends among wind power project owners and power purchasers. The report then turns to a summary of wind turbine technology trends: turbine size, hub height, rotor diameter, specific power, and IEC Class. After that, the report discusses wind power performance, cost, and pricing trends. In so doing, it describes

Meteorological aspects of siting large wind turbines

Energy Technology Data Exchange (ETDEWEB)

Hiester, T.R.; Pennell, W.T.

1981-01-01

This report, which focuses on the meteorological aspects of siting large wind turbines (turbines with a rated output exceeding 100 kW), has four main goals. The first is to outline the elements of a siting strategy that will identify the most favorable wind energy sites in a region and that will provide sufficient wind data to make responsible economic evaluations of the site wind resource possible. The second is to critique and summarize siting techniques that were studied in the Department of Energy (DOE) Wind Energy Program. The third goal is to educate utility technical personnel, engineering consultants, and meteorological consultants (who may have not yet undertaken wind energy consulting) on meteorological phenomena relevant to wind turbine siting in order to enhance dialogues between these groups. The fourth goal is to minimize the chances of failure of early siting programs due to insufficient understanding of wind behavior.

Review of fluid and control technology of hydraulic wind turbines

Institute of Scientific and Technical Information of China (English)

Maolin CAI; Yixuan WANG; Zongxia JIAO; Yan SHI

2017-01-01

This study examines the development of the fluid and control technology of hydraulic wind turbines.The current state of hydraulic wind turbines as a new technology is described,and its basic fluid model and typical control method are expounded by comparing various study results.Finally,the advantages of hydraulic wind turbines are enumerated.Hydraulic wind turbines are expected to become the main development direction of wind turbines.

Review of fluid and control technology of hydraulic wind turbines

Science.gov (United States)

Cai, Maolin; Wang, Yixuan; Jiao, Zongxia; Shi, Yan

2017-09-01

This study examines the development of the fluid and control technology of hydraulic wind turbines. The current state of hydraulic wind turbines as a new technology is described, and its basic fluid model and typical control method are expounded by comparing various study results. Finally, the advantages of hydraulic wind turbines are enumerated. Hydraulic wind turbines are expected to become the main development direction of wind turbines.

Wind turbines - facts from 20 years of technological progress

Energy Technology Data Exchange (ETDEWEB)

Hansen, L H; Dannemand Andersen, P [Risoe Ntaional Lab., Roskilde (Denmark)

1999-03-01

The first Danish commercial wind turbines were installed in the late 1970s. Over the last 20 years the Danish wind turbine market has been relatively stable concerning annual installations, and the wind turbine technology has been able to develop continuously. This gives a unique time track for technology analysts. The aim of this paper is to extract reliable information on this time track from existing archives and statistics. Seven generations of wind turbine technology have been identified mainly based on `characteristic` rotor diameters. The technological development of each generation is described using indicators such as: market share in Denmark, generator size, rotor diameter, hub height, electricity production and productivity. Economical indicators comprise: costs of turbine and standard foundation. (au)

Wind turbines - facts from 20 years of technological progress

International Nuclear Information System (INIS)

Hansen, L.H.; Dannemand Andersen, P.

1999-01-01

The first Danish commercial wind turbines were installed in the late 1970s. Over the last 20 years the Danish wind turbine market has been relatively stable concerning annual installations, and the wind turbine technology has been able to develop continuously. This gives a unique time track for technology analysts. The aim of this paper is to extract reliable information on this time track from existing archives and statistics. Seven generations of wind turbine technology have been identified mainly based on 'characteristic' rotor diameters. The technological development of each generation is described using indicators such as: market share in Denmark, generator size, rotor diameter, hub height, electricity production and productivity. Economical indicators comprise: costs of turbine and standard foundation. (au)

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.

Structural Flexibility of Large Direct Drive Generators for Wind Turbines

NARCIS (Netherlands)

Shrestha, G.

2013-01-01

The trend in wind energy is towards large offshore wind farms. This trend has led to the demand for high reliability and large single unit wind turbines. Different energy conversion topologies such as multiple stage geared generators, single stage geared generators and gearless (direct drive)

Technology Roadmaps: How2Guide for Wind Energy Roadmap

Energy Technology Data Exchange (ETDEWEB)

NONE

2014-03-01

Whether in OECD, emerging or developing country economies, governments are increasingly looking to diversify their energy mix beyond simply fossil fuels. While wind energy is developing towards a mainstream, competitive and reliable technology, a range of barriers can delay progress, such as financing, grid integration, social acceptance and aspects of planning processes. National and regional technology roadmaps can play a key role in supporting wind energy development and implementation, helping countries to identify priorities and pathways tailored to local resources and markets. Recognising this, the IEA has started the How2Guides - a new series co-ordinated by the International Low-Carbon Energy Technology Platform to address the need for more focused guidance in the development of national roadmaps, or strategies, for specific low-carbon technologies. This builds on the success of the IEA global technology roadmap series and responds to a growing number of requests for IEA guidance to adapt the findings of the IEA global technology roadmaps to national circumstances. A successful roadmap contains a clear statement of the desired outcome, followed by a specific pathway for reaching it. The How2Guide for Wind Energy builds on the IEA well established methodology for roadmap development and shares wind specific recommendations on how to address the four phases to developing and implementing a wind energy roadmap: Planning; Visioning; Development; and Implementation. The manual also offers menus of recommendations on policy and technical options for deployment of utility-scale wind energy installations. A matrix of barriers-versus-realistic solutions options is cross-listed with considerations such as planning, development, electricity market and system, infrastructure, and finance and economics. Drawing on several case studies from around the globe, as well as on the IEA Technology Roadmap for Wind Energy, the How2Guide for Wind Energy it is intended as a

Cost optimization of wind turbines for large-scale offshore wind farms

International Nuclear Information System (INIS)

Fuglsang, P.; Thomsen, K.

1998-02-01

This report contains a preliminary investigation of site specific design of off-shore wind turbines for a large off-shore wind farm project at Roedsand that is currently being proposed by ELKRAFT/SEAS. The results were found using a design tool for wind turbines that involve numerical optimization and aeroelastic calculations of response. The wind climate was modeled in detail and a cost function was used to estimate costs from manufacture and installation. Cost of energy is higher for off-shore installations. A comparison of an off-shore wind farm site with a typical stand alone on-shore site showed an increase of the annual production of 28% due to the difference in wind climate. Extreme loads and blade fatigue loads were nearly identical, however,fatigue loads on other main components increased significantly. Optimizations were carried out to find the optimum overall off-shore wind turbine design. A wind turbine for the off-shore wind farm should be different compared with a stand-alone on-shore wind turbine. The overall design changed were increased swept area and rated power combined with reduced rotor speed and tower height. Cost was reduced by 12% for the final 5D/14D off-shore wind turbine from 0.306 DKr/kWh to 0.270 DKr/kWh. These figures include capital costs from manufacture and installation but not on-going costs from maintenance. These results make off-shore wind farms more competitive and comparable to the reference on-shore stand-alone wind turbine. A corresponding reduction of cost of energy could not be found for the stand alone on-shore wind turbine. Furthermore the fatigue loads on wind turbines in on-shore wind farms will increase and cost of energy will increase in favor of off-shore wind farms. (au) EFP-95; EU-JOULE-3; 21 tabs., 7 ills., 8 refs

2011 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoen, Ben [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Porter, Kevin [Exeter Associates, Columbia, MD (United States); Buckley, Michael [Exeter Associates, Columbia, MD (United States); Fink, Sari [Exeter Associates, Columbia, MD (United States); Oteri, Frank [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tegen, Suzanne [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2012-08-01

The U.S. wind power industry is facing uncertain times. With 2011 capacity additions having risen from 2010 levels and with a further sizable increase expected in 2012, there are – on the surface – grounds for optimism. Key factors driving growth in 2011 included continued state and federal incentives for wind energy, recent improvements in the cost and performance of wind power technology, and the need to meet an end-of-year construction start deadline in order to qualify for the Section 1603 Treasury grant program. At the same time, the currently-slated expiration of key federal tax incentives for wind energy at the end of 2012 – in concert with continued low natural gas prices and modest electricity demand growth – threatens to dramatically slow new builds in 2013.

Small Wind Turbine Technology Assessment; Estado del Arte de la Tecnologia de Pequeos Aerogeneradores

Energy Technology Data Exchange (ETDEWEB)

Avia Aranda, F; Cruz Cruz, I [CIEMAT. Madrid (Spain)

1999-03-01

The result of the study carried out under the scope of the ATYCA project Test Plant of Wind Systems for Isolated Applications, about the state of art of the small wind turbine technology (wind turbines with swept area smaller than 40 m``2) is presented. The study analyzes the collected information on 60 models of wind turbines from 23 manufactures in the worldwide market. Data from Chinese manufacturers, that have a large participation in the total number of small turbines in operation, are not included, due to the unavailability of the technical information. (Author) 15 refs.

Composite rotor blades for large wind energy installations

Science.gov (United States)

Kussmann, A.; Molly, J.; Muser, D.

1980-01-01

The design of large wind power systems in Germany is reviewed with attention given to elaboration of the total wind energy system, aerodynamic design of the rotor blade, and wind loading effects. Particular consideration is given to the development of composite glass fiber/plastic or carbon fiber/plastic rotor blades for such installations.

Composite rotor blades for large wind energy installations

Energy Technology Data Exchange (ETDEWEB)

Kussmann, A; Molly, J P; Muser, D

1979-06-01

The design of large wind power systems in Germany is reviewed with attention given to elaboration of the total wind energy system, aerodynamic design of the rotor blade, and wind loading effects. Particular consideration is given to the development of composite glass fiber/plastic or carbon fiber/plastic rotor blades for such installations.

Modelling and transient stability of large wind farms

DEFF Research Database (Denmark)

Akhmatov, Vladislav; Knudsen, Hans; Nielsen, Arne Hejde

2003-01-01

by a physical model of grid-connected windmills. The windmill generators ate conventional induction generators and the wind farm is ac-connected to the power system. Improvements-of short-term voltage stability in case of failure events in the external power system are treated with use of conventional generator...... technology. This subject is treated as a parameter study with respect to the windmill electrical and mechanical parameters and with use of control strategies within the conventional generator technology. Stability improvements on the wind farm side of the connection point lead to significant reduction...

Fostering a renewable energy technology industry: an international comparison of wind industry policy support mechanisms

International Nuclear Information System (INIS)

Lewis, J.I.; Wiser, R.H.

2007-01-01

This article examines the importance of national and sub-national policies in supporting the development of successful global wind turbine manufacturing companies. We explore the motivations behind establishing a local wind power industry, and the paths that different countries have taken to develop indigenous large wind turbine manufacturing industries within their borders. This is done through a cross-country comparison of the policy support mechanisms that have been employed to directly and indirectly promote wind technology manufacturing in 12 countries. We find that in many instances there is a clear relationship between a manufacturer's success in its home country market and its eventual success in the global wind power market. Whether new wind turbine manufacturing entrants are able to succeed will likely depend in part on the utilization of their turbines in their own domestic market, which is turn will be influenced by the annual size and stability of that market. Consequently, policies that support a sizable, stable market for wind power, in conjunction with policies that specifically provide incentives for wind power technology to be manufactured locally, are most likely to result in the establishment of an internationally competitive wind industry. (author)

Fostering a renewable energy technology industry: An international comparison of wind industry policy support mechanisms

International Nuclear Information System (INIS)

Lewis, Joanna I.; Wiser, Ryan H.

2007-01-01

This article examines the importance of national and sub-national policies in supporting the development of successful global wind turbine manufacturing companies. We explore the motivations behind establishing a local wind power industry, and the paths that different countries have taken to develop indigenous large wind turbine manufacturing industries within their borders. This is done through a cross-country comparison of the policy support mechanisms that have been employed to directly and indirectly promote wind technology manufacturing in 12 countries. We find that in many instances there is a clear relationship between a manufacturer's success in its home country market and its eventual success in the global wind power market. Whether new wind turbine manufacturing entrants are able to succeed will likely depend in part on the utilization of their turbines in their own domestic market, which in turn will be influenced by the annual size and stability of that market. Consequently, policies that support a sizable, stable market for wind power, in conjunction with policies that specifically provide incentives for wind power technology to be manufactured locally, are most likely to result in the establishment of an internationally competitive wind industry

Flow and wakes in large wind farms: Final report for UpWind WP8

DEFF Research Database (Denmark)

Barthelmie, Rebecca Jane; Frandsen, Sten Tronæs; Rathmann, Ole

This report summarises the research undertaken through the European Commission funded project UpWind Wp8:Flow. The objective of the work was to develop understanding of flow in large wind farms and to evaluate models of power losses due to wind turbine wakes focusing on complex terrain and offshore...

Financing innovative technologies in wind projects

International Nuclear Information System (INIS)

Vaughan, C.

2006-01-01

Methods of market entry and the financing of new technologies were discussed from the perspective of Clipper Windpower, a wind energy company based in the northeastern United States and Canada. Many new technology companies only consider private equity when seeking financing for new product development. However, financing for projects and products is only the first step to market entry. Wind projects are the financial equivalent of a high yield bond with mechanical risk. Many wind power projects with company equity can also be seen as a long term bond with upside in any given year. It is therefore important for wind developers to seek out strategic buyers for both product development and project development, in addition to finding sources of private equity. Clipper Windpower Inc. has developed a partnership with British Petroleum (BP), who hold an equity interest in the company. Both companies are now partnering on projects with Clipper turbines, and firm orders are in place for 2007 and 2008. As a result of the partnership, Clipper now has increased its financial strength in cash flows, balance sheets, and projected revenue. It was concluded that a successful partnership can increase the scale of wind power development, and bring financial sophistication to smaller companies with limited resources. refs., tabs., figs

Draft South African wind energy technology platform: preliminary wind energy research and development framework

CSIR Research Space (South Africa)

Szewczuk, S

2011-08-01

Full Text Available The South African Wind Energy Technology Programme (SAWEP) Phase 1 aims to achieve two key strategic outputs that will guide South Africa on wind energy development. One of these outputs is the Wind Atlas for South Africa (WASA) which will play a...

Energy System Analysis of Large-Scale Integration of Wind Power

International Nuclear Information System (INIS)

Lund, Henrik

2003-11-01

The paper presents the results of two research projects conducted by Aalborg University and financed by the Danish Energy Research Programme. Both projects include the development of models and system analysis with focus on large-scale integration of wind power into different energy systems. Market reactions and ability to exploit exchange on the international market for electricity by locating exports in hours of high prices are included in the analyses. This paper focuses on results which are valid for energy systems in general. The paper presents the ability of different energy systems and regulation strategies to integrate wind power, The ability is expressed by three factors: One factor is the degree of electricity excess production caused by fluctuations in wind and CHP heat demands. The other factor is the ability to utilise wind power to reduce CO 2 emission in the system. And the third factor is the ability to benefit from exchange of electricity on the market. Energy systems and regulation strategies are analysed in the range of a wind power input from 0 to 100% of the electricity demand. Based on the Danish energy system, in which 50 per cent of the electricity demand is produced in CHP, a number of future energy systems with CO 2 reduction potentials are analysed, i.e. systems with more CHP, systems using electricity for transportation (battery or hydrogen vehicles) and systems with fuel-cell technologies. For the present and such potential future energy systems different regulation strategies have been analysed, i.e. the inclusion of small CHP plants into the regulation task of electricity balancing and grid stability and investments in electric heating, heat pumps and heat storage capacity. Also the potential of energy management has been analysed. The results of the analyses make it possible to compare short-term and long-term potentials of different strategies of large-scale integration of wind power

Flow and wakes in large wind farms. Final report for UpWind WP8

Energy Technology Data Exchange (ETDEWEB)

Barthelmie, R.J.; Frandsen, S.T.; Rathmann, O. (Risoe DTU (Denmark)); Hansen, K. (Technical Univ. of Denmark (DTU), Kgs. Lyngby (Denmark)); Politis, E.; Prospathopoulos, J. (CRES (Greece)); Schepers, J.G. (ECN, Petten (Netherlands)); Rados, K. (NTUA, Athens (Greece)); Cabezon, D. (CENER, Sarriguren (Spain)); Schlez, W.; Neubert, A.; Heath, M. (Garrad Hassan and Partners (Germany) (United Kingdom))

2011-02-15

This report summarises the research undertaken through the European Commission funded project UpWind Wp8:Flow. The objective of the work was to develop understanding of flow in large wind farms and to evaluate models of power losses due to wind turbine wakes focusing on complex terrain and offshore. A crosscutting activity was to improve and compare the performance of computational fluid dynamics models with wind farm models. The report contains 6 deliverable reports and guideline to wind farm wake analysis as appendices. (Author)

The impacts of wind technology advancement on future global energy

International Nuclear Information System (INIS)

Zhang, Xiaochun; Ma, Chun; Song, Xia; Zhou, Yuyu; Chen, Weiping

2016-01-01

Highlights: • Integrated assessment model perform a series of scenarios of technology advances. • Explore the potential roles of wind energy technology advance in global energy. • Technology advance impacts on energy consumption and global low carbon market. • Technology advance influences on global energy security and stability. - Abstract: To avoid additional global warming and environmental damage, energy systems need to rely on the use of low carbon technologies like wind energy. However, supply uncertainties, production costs, and energy security are the main factors considered by the global economies when reshaping their energy systems. Here, we explore the potential roles of wind energy technology advancement in future global electricity generations, costs, and energy security. We use an integrated assessment model performing a series of technology advancement scenarios. The results show that double of the capital cost reduction causes 40% of generation increase and 10% of cost ​decrease on average in the long-term global wind electricity market. Today’s technology advancement could bring us the benefit of increasing electricity production in the future 40–50 years, and decreasing electricity cost in the future 90–100 years. The technology advancement of wind energy can help to keep global energy security and stability. An aggressive development and deployment of wind energy could in the long-term avoid 1/3 of gas and 1/28 of coal burned, and keep 1/2 biomass and 1/20 nuclear fuel saved from the global electricity system. The key is that wind resources are free and carbon-free. The results of this study are useful in broad coverage ranges from innovative technologies and systems of renewable energy to the economic industrial and domestic use of energy with no or minor impact on the environment.

Effects of large scale integration of wind and solar energy in Japan

Science.gov (United States)

Esteban, Miguel; Zhang, Qi; Utama, Agya; Tezuka, Tetsuo; Ishihara, Keiichi

2010-05-01

results for the country as a whole are considered it is still substantial. The results are greatly dependant on the mix between the proposed renewables (solar and wind), and by comparing different distributions and mixes, the optimum composition for the target country can be established. The methodology proposed is able to obtain the optimum mix of solar and wind power for a given system, provided that adequate storage capacity exists to allow for excess capacity to be used at times of low electricity production (at the comparatively rare times when there is neither enough sun nor wind throughout the country). This highlights the challenges of large-scale integration of renewable technologies into the electricity grid, and the necessity to combine such a system with other renewables such as hydro or ocean energy to further even out the peaks and lows in the demand.

Wind Power: Building and Connecting Large Wind Power Plants; Vindkraft: bygga och ansluta stoerre vindkraftverk

Energy Technology Data Exchange (ETDEWEB)

2007-09-15

This brochure is written for those who want to build a large wind power plant (1 MW or more) or wind power parks. It describes the process from idea to completed plant. A review of environmental impacts of wind power is also included

Power Electronics as key technology in wind turbines

DEFF Research Database (Denmark)

Blaabjerg, Frede

2005-01-01

This paper discuss the development in wind turbines in a two-decade perspective looking at the technology based on track records. Different power electronic topologies for interfacing the wind turbine to the grid are discussed and related to the possibility for the wind turbine to act as a power...

Explaining technological change of wind power in China and the United States: Roles of energy policies, technological learning, and collaboration

Science.gov (United States)

Tang, Tian

The following dissertation explains how technological change of wind power, in terms of cost reduction and performance improvement, is achieved in China and the US through energy policies, technological learning, and collaboration. The objective of this dissertation is to understand how energy policies affect key actors in the power sector to promote renewable energy and achieve cost reductions for climate change mitigation in different institutional arrangements. The dissertation consists of three essays. The first essay examines the learning processes and technological change of wind power in China. I integrate collaboration and technological learning theories to model how wind technologies are acquired and diffused among various wind project participants in China through the Clean Development Mechanism (CDM)--an international carbon trade program, and empirically test whether different learning channels lead to cost reduction of wind power. Using pooled cross-sectional data of Chinese CDM wind projects and spatial econometric models, I find that a wind project developer's previous experience (learning-by-doing) and industrywide wind project experience (spillover effect) significantly reduce the costs of wind power. The spillover effect provides justification for subsidizing users of wind technologies so as to offset wind farm investors' incentive to free-ride on knowledge spillovers from other wind energy investors. The CDM has played such a role in China. Most importantly, this essay provides the first empirical evidence of "learning-by-interacting": CDM also drives wind power cost reduction and performance improvement by facilitating technology transfer through collaboration between foreign turbine manufacturers and local wind farm developers. The second essay extends this learning framework to the US wind power sector, where I examine how state energy policies, restructuring of the electricity market, and learning among actors in wind industry lead to

Wind speed reductions by large-scale wind turbine deployments lower turbine efficiencies and set low wind power potentials

Science.gov (United States)

Miller, Lee; Kleidon, Axel

2017-04-01

Wind turbines generate electricity by removing kinetic energy from the atmosphere. Large numbers of wind turbines are likely to reduce wind speeds, which lowers estimates of electricity generation from what would be presumed from unaffected conditions. Here, we test how well wind power potentials that account for this effect can be estimated without explicitly simulating atmospheric dynamics. We first use simulations with an atmospheric general circulation model (GCM) that explicitly simulates the effects of wind turbines to derive wind power limits (GCM estimate), and compare them to a simple approach derived from the climatological conditions without turbines [vertical kinetic energy (VKE) estimate]. On land, we find strong agreement between the VKE and GCM estimates with respect to electricity generation rates (0.32 and 0.37 We m-2) and wind speed reductions by 42 and 44%. Over ocean, the GCM estimate is about twice the VKE estimate (0.59 and 0.29 We m-2) and yet with comparable wind speed reductions (50 and 42%). We then show that this bias can be corrected by modifying the downward momentum flux to the surface. Thus, large-scale limits to wind power can be derived from climatological conditions without explicitly simulating atmospheric dynamics. Consistent with the GCM simulations, the approach estimates that only comparatively few land areas are suitable to generate more than 1 We m-2 of electricity and that larger deployment scales are likely to reduce the expected electricity generation rate of each turbine. We conclude that these atmospheric effects are relevant for planning the future expansion of wind power.

Large-scale wind energy application. Transporting wind energy over long distances using an HVDC transmission line, in combination with hydro energy or biomass energy

International Nuclear Information System (INIS)

Coelingh, J.P.; Van Wijk, A.J.M.; Betcke, J.W.H.; Geuzendam, C.; Gilijamse, W.; Westra, C.A.; Curvers, A.P.W.M.; Beurskens, H.J.M.

1995-08-01

The main objective of the study on the title subject is to assess the long-term prospects for large-scale application of wind energy, in combination with hydro energy in Norway and in combination with biomass energy in Scotland. These countries have high wind resource areas, however they are located far away from load centres. The development of new transmission technologies as High Voltage Direct Current (HVDC) transmission lines, in combination with highly suitable places for wind energy in Norway and Scotland, forms the driving force behind this study. The following two cases are being considered: (1) a large-scale wind farm (1,000 MW) in Norway from which electricity is transmitted to The Netherlands by using an HVDC transmission line, in combination with hydro energy. Hydro energy already makes a large contribution to the energy supply of Norway. Wind farms can contribute to the electricity production and save hydro energy generated electricity and make the export of electricity profitable; and (2) a large-scale wind farm (1,000 MW) in Scotland from which electricity is transmitted to The Netherlands by using an HVDC transmission line, in combination with biomass energy. Scotland has a large potential for biomass production such as energy crops and forestry. Poplars and willows cultivated on set-aside land can be gasified and fed into modern combined-cycle plants to generate electricity. In Scotland the usable potential of wind energy may be limited in the short and medium term by the capacity of the grid. New connections can overcome this constraint and allow wind energy to be treated as a European Union resource rather than as a national resource. Thus, the concept of this study is to look at the possibilities of making a 1,000 MW link from The Netherlands to Norway or to Scotland, in order to supply electricity at competitive costs generated with renewable energy sources. 16 figs., 24 tabs., 80 refs

IEA Wind Task 23, offshore wind technology and deployment. Subtask 1: Experience with critical deployment issues. Final technical report

Energy Technology Data Exchange (ETDEWEB)

Lemming, J

2010-10-15

The final report for IEA Wind Task 23, Offshore Wind Energy Technology and Deployment, is made up of two separate reports: Subtask 1: Experience with Critical Deployment Issues and Subtask 2: Offshore Code Comparison Collaborative (OC3). The Subtask 1 report included here provides background information and objectives of Task 23. It specifically discusses ecological issues and regulation, electrical system integration and offshore wind, external conditions, and key conclusions for Subtask 1. A comprehensive approach to planning is needed that integrates impacts on ecology, the effects of electrical infrastructure, and the layout of wind farms. Governments, which usually finance ecological research, should disclose results for wide dissemination as they become available. As example the workshop held suggested that documents covering the issues like offshore wind energy legislation, Guidelines for EIAs and SEAs and best practices need to be produced and distributed on a regular basis, as ecological research progresses and experience from the planning and operation of existing wind farms emerges. Research should help strike the balance between optimum regulation and the need to get projects up and running. Such research is needed to increase understanding of offshore wind metrology and its impact on electrical power fluctuations. More work is needed to develop special grid code and standards for offshore. The transient behavior of large cable installations (switching / harmonic/ Behavior and modeling of large HV cable systems) must be better understood. Connection and control systems must be developed for large offshore wind farms. Work is needed to develop the technical architecture of offshore wind grid systems. Public access to measurements (e.g., turbine power output, meteorological masts, buoys) is important, especially for model validation. Determining wake effects is currently the most important challenge in wind engineering. Emphasis should be put into

Energy Dynamics of an Infinitely Large Offshore Wind Farm

DEFF Research Database (Denmark)

Frandsen, Sten Tronæs; Barthelmie, R.J.; Pryor, S.C.

, particularly in the near-term, can be expected in the higher resource, moderate water depths of the North Sea rather than the Mediterranean. There should therefore be significant interest in understanding the energy dynamics of the infinitely large wind farm – how wakes behave and whether the extraction...... of energy by wind turbines over a large area has a significant and lasting impact on the atmospheric boundary layer. Here we focus on developing understanding of the infinite wind farm through a combination of theoretical considerations, data analysis and modeling. Initial evaluation of power losses due...... is of about the same magnitude as for the infinitely large wind farm. We will examine whether this can be proved theoretically or is indicated by data currently available. We will also evaluate whether energy extraction at the likely scale of development in European Seas can be expected to modulate...

Increasing the competitiveness of wind energy. New technologies for advanced wind predictability

International Nuclear Information System (INIS)

Bertolotti, Fabio

2013-01-01

The performance of thermal and nuclear power plants is assessed routinely and precisely, whereas the performance assessment of wind turbines is lagging far behind. This increases operational costs, reduces energy capture, and makes wind energy less competitive. The paper presents a technology and system with improved 24-h power forecasting, as well as condition monitoring of the rotor blades. The system can be employed by any wind power plant and offers potentials to increase the competitiveness of the power industry. (orig.)

Study of LANs access technologies in wind power system

DEFF Research Database (Denmark)

Wei, Mu; Chen, Zhe

2010-01-01

Due to the energy challenges in the world, new types of generation technologies, such as renewable energy based generators, attract great attention and are being quickly developed, which results in the dramatic developments and changes in modern power systems, the communication technologies play...... a increasingly important role in guaranteeing the power system’s stability, reliability, and security. In this paper the necessity of communication technologies employed in wind power system are introduced. According the International Standards Organization (ISO) reference 7-layered model, the communication...... power environment are explained and discussed. Furthermore the simulation of application of Ethernet in an offshore wind farm communication network by a software, OPNET, is elaborated. With the investigation of the communication technologies in this paper, the offshore wind farm SCADA system can...

Balancing modern Power System with large scale of wind power

DEFF Research Database (Denmark)

Basit, Abdul; Altin, Müfit; Hansen, Anca Daniela

2014-01-01

Power system operators must ensure robust, secure and reliable power system operation even with a large scale integration of wind power. Electricity generated from the intermittent wind in large propor-tion may impact on the control of power system balance and thus deviations in the power system...... frequency in small or islanded power systems or tie line power flows in interconnected power systems. Therefore, the large scale integration of wind power into the power system strongly concerns the secure and stable grid operation. To ensure the stable power system operation, the evolving power system has...... to be analysed with improved analytical tools and techniques. This paper proposes techniques for the active power balance control in future power systems with the large scale wind power integration, where power balancing model provides the hour-ahead dispatch plan with reduced planning horizon and the real time...

Dynamic Reactive Power Compensation of Large Scale Wind Integrated Power System

DEFF Research Database (Denmark)

Rather, Zakir Hussain; Chen, Zhe; Thøgersen, Paul

2015-01-01

wind turbines especially wind farms with additional grid support functionalities like dynamic support (e,g dynamic reactive power support etc.) and ii) refurbishment of existing conventional central power plants to synchronous condensers could be one of the efficient, reliable and cost effective option......Due to progressive displacement of conventional power plants by wind turbines, dynamic security of large scale wind integrated power systems gets significantly compromised. In this paper we first highlight the importance of dynamic reactive power support/voltage security in large scale wind...... integrated power systems with least presence of conventional power plants. Then we propose a mixed integer dynamic optimization based method for optimal dynamic reactive power allocation in large scale wind integrated power systems. One of the important aspects of the proposed methodology is that unlike...

Wind Energy

International Nuclear Information System (INIS)

Rodriguez D, J.M.

1998-01-01

The general theory of the wind energy conversion systems is presented. The availability of the wind resource in Colombia and the ranges of the speed of the wind in those which is possible economically to use the wind turbines are described. It is continued with a description of the principal technological characteristics of the wind turbines and are split into wind power and wind-powered pumps; and its use in large quantities grouped in wind farms or in autonomous systems. Finally, its costs and its environmental impact are presented

Wind lens technology and its application to wind and water turbine and beyond

Directory of Open Access Journals (Sweden)

Ohya Yuji

2017-01-01

Full Text Available Wind lens is a new type of wind power system consisting of a simple brimmed ring structure that surrounds the rotor causing greater wind to pass through the turbine. As a consequence, the turbine's efficiency of capturing energy from the wind gets dramatically increased. A Wind lens turbine can generate 2–5 times the power of an existing wind turbine given at the same rotor diameter and incoming wind speed. This fluid dynamical effect is also effective in the water. We have developed 1–3 kW Wind lens turbines and a 100 kW Wind lens turbine. In addition to the enhanced output power, Wind lens turbine is quiet. The technology is now used in an offshore experiment with a hexagonal float 18 meters in diameter set off the coast of Hakata Bay in Fukuoka City. Moreover, we are now pursuing larger size Wind lens turbines through multi-rotor design consisting of multiple Wind lens turbines in a same vertical plane to embody larger total power output.

2012 Market Report on U.S. Wind Technologies in Distributed Applications

Energy Technology Data Exchange (ETDEWEB)

Orrell, Alice C.; Flowers, L. T.; Gagne, M. N.; Pro, B. H.; Rhoads-Weaver, H. E.; Jenkins, J. O.; Sahl, K. M.; Baranowski, R. E.

2013-08-06

At the end of 2012, U.S. wind turbines in distributed applications reached a 10-year cumulative installed capacity of more than 812 MW from more than 69,000 units across all 50 states. In 2012 alone, nearly 3,800 wind turbines totaling 175 MW of distributed wind capacity were documented in 40 states and in the U.S. Virgin Islands, with 138 MW using utility-scale turbines (i.e., greater than 1 MW in size), 19 MW using mid-size turbines (i.e., 101 kW to 1 MW in size), and 18.4 MW using small turbines (i.e., up to 100 kW in size). Distributed wind is defined in terms of technology application based on a wind project’s location relative to end-use and power-distribution infrastructure, rather than on technology size or project size. Distributed wind systems are either connected on the customer side of the meter (to meet the onsite load) or directly to distribution or micro grids (to support grid operations or offset large loads nearby). Estimated capacity-weighted average costs for 2012 U.S. distributed wind installations was $2,540/kW for utility-scale wind turbines, $2,810/kW for mid-sized wind turbines, and $6,960/kW for newly manufactured (domestic and imported) small wind turbines. An emerging trend observed in 2012 was an increased use of refurbished turbines. The estimated capacity-weighted average cost of refurbished small wind turbines installed in 2012 was $4,080/kW. As a result of multiple projects using utility-scale turbines, Iowa deployed the most new overall distributed wind capacity, 37 MW, in 2012. Nevada deployed the most small wind capacity in 2012, with nearly 8 MW of small wind turbines installed in distributed applications. In the case of mid-size turbines, Ohio led all states in 2012 with 4.9 MW installed in distributed applications. State and federal policies and incentives continued to play a substantial role in the development of distributed wind projects. In 2012, U.S. Treasury Section 1603 payments and grants and loans from the U

Technology Performance Report: Duke Energy Notrees Wind Storage Demonstration Project

Energy Technology Data Exchange (ETDEWEB)

Wehner, Jeff [Duke Energy Renewables, Charlotte, NC (United States); Mohler, David [Duke Energy Renewables, Charlotte, NC (United States); Gibson, Stuart [Duke Energy Renewables, Charlotte, NC (United States); Clanin, Jason [Duke Energy Renewables, Charlotte, NC (United States); Faris, Don [Duke Energy Renewables, Charlotte, NC (United States); Hooker, Kevin [Duke Energy Renewables, Charlotte, NC (United States); Rowand, Michael [Duke Energy Renewables, Charlotte, NC (United States)

2015-11-01

Duke Energy Renewables owns and operates the Notrees Wind Farm in west Texas’s Ector and Winkler counties. The wind farm, which was commissioned in April 2009, has a total capacity of 152.6 MW generated by 55 Vestas V82 turbines, one Vestas 1-V90 experimental turbine, and 40 GE 1.5-MW turbines. The Vestas V82 turbines have a generating capacity of 1.65 MW each, the Vestas V90 turbine has a generating capacity of 1.86 MW, and the GE turbines have a generating capacity of 1.5 MW each. The objective of the Notrees Wind Storage Demonstration Project is to validate that energy storage increases the value and practical application of intermittent wind generation and is commercially viable at utility scale. The project incorporates both new and existing technologies and techniques to evaluate the performance and potential of wind energy storage. In addition, it could serve as a model for others to adopt and replicate. Wind power resources are expected to play a significant part in reducing greenhouse gas emissions from electric power generation by 2030. However, the large variability and intermittent nature of wind presents a barrier to integrating it within electric markets, particularly when competing against conventional generation that is more reliable. In addition, wind power production often peaks at night or other times when demand and electricity prices are lowest. Energy storage systems can overcome those barriers and enable wind to become a valuable asset and equal competitor to conventional fossil fuel generation.

An Evaluation of Wind Turbine Technology at Peterson Air Force Base

Science.gov (United States)

2005-03-01

by the wind speed. Darrieus turbines are ordinarily inexpensive and are used for electricity generation and irrigation. One advantage to a...AN EVALUATION OF WIND TURBINE TECHNOLOGY...02 AN EVALUATION OF WIND TURBINE TECHNOLOGY AT PETERSON AIR FORCE BASE THESIS Presented to the Faculty Department of

Investigation on the integral output power model of a large-scale wind farm

Institute of Scientific and Technical Information of China (English)

BAO Nengsheng; MA Xiuqian; NI Weidou

2007-01-01

The integral output power model of a large-scale wind farm is needed when estimating the wind farm's output over a period of time in the future.The actual wind speed power model and calculation method of a wind farm made up of many wind turbine units are discussed.After analyzing the incoming wind flow characteristics and their energy distributions,and after considering the multi-effects among the wind turbine units and certain assumptions,the incoming wind flow model of multi-units is built.The calculation algorithms and steps of the integral output power model of a large-scale wind farm are provided.Finally,an actual power output of the wind farm is calculated and analyzed by using the practical measurement wind speed data.The characteristics of a large-scale wind farm are also discussed.

Fatigue Analysis of Large-scale Wind turbine

Directory of Open Access Journals (Sweden)

Zhu Yongli

2017-01-01

Full Text Available The paper does research on top flange fatigue damage of large-scale wind turbine generator. It establishes finite element model of top flange connection system with finite element analysis software MSC. Marc/Mentat, analyzes its fatigue strain, implements load simulation of flange fatigue working condition with Bladed software, acquires flange fatigue load spectrum with rain-flow counting method, finally, it realizes fatigue analysis of top flange with fatigue analysis software MSC. Fatigue and Palmgren-Miner linear cumulative damage theory. The analysis result indicates that its result provides new thinking for flange fatigue analysis of large-scale wind turbine generator, and possesses some practical engineering value.

Wind energy technology development and diffusion: a case study of Inner Mongolia, China

International Nuclear Information System (INIS)

Xiliang Zhang; Shuhua Gu; Wenqiang Liu; Lin Gan

2001-01-01

This article reviews the spread of small household wind generators and the development of wind farms in Inner Mongolia, China with emphasis on policy and institutional perspectives. It analyses the patterns of wind technology dissemination within social, economic, and environmental contexts. It also discusses international investment and technology transfer relating to wind energy technology. The economics of windfarm development are examined and the role of alternative policy instruments analysed. Major constraints to wind technology development are identified and relevant policy recommendations suggested. (Author)

Wind energy technology development and diffusion: a case study of Inner Mongolia, China

International Nuclear Information System (INIS)

Zhang Xiliang; Liu Wenqiang; Gu Shuhua; Gan Lin

2001-01-01

This article reviews the spread of small household wind generators and the development of wind farms in Inner Mongolia, China with emphasis on policy and institutional perspectives. It analyzes the patterns of wind technology dissemination within social, economic, and environmental contexts. It also discusses international investment and technology transfer relating to wind energy technology. The economics of windfarm development are examined and the role of alternative policy instruments analyzed. Major constraints to wind technology development are identified and relevant policy recommendations suggested. (author)

Effects of Turbine Spacings in Very Large Wind Farms

DEFF Research Database (Denmark)

farm. LES simulations of large wind farms are performed with full aero-elastic Actuator Lines. The simulations investigate the inherent dynamics inside wind farms in the absence of atmospheric turbulence compared to cases with atmospheric turbulence. Resulting low frequency structures are inherent...... in wind farms for certain turbine spacings and affect both power production and loads...

Transition of wind power utilization technology in the 20th century; 20 seiki ni okeru furyoku riyo gijutsu no hensen

Energy Technology Data Exchange (ETDEWEB)

Ushiyama, I. [Ashikaga Inst. of Tech., Tochigi (Japan)

2000-04-01

Windmills are one of the oldest prime movers and have been used for more than 700 years in Europe. The transition from low speed windmills for grain grinding and water pumping to high speed wind turbines for electric power generation had occurred at the end of 19{sup th} century. This paper, at first, reviews the windmill technologies and the researchers before 20th century. Then describes the back ground of how the wind power generator has existed and how the four pioneers developed their wind power generator. The historical developments of windmills to wind turbines in this century are studied focusing mainly on Danish activities. Then, the effort of the development of large wind turbine such as Smith-Putnum's first MW machine in U.S.A. and other mammoth machine concept are introduced. The new concept machines such as Savonius and Darrieus wind turbines in 1920s to 1930s are also explained. Finally, the novel technologies of wind turbine covering larger machines, variable speed generators, special wing sections for wind turbines, theoretical analysis method of wind turbine performance, offshore wind turbines, and wind turbine control technologies are stated. (author)

National Offshore Wind Energy Grid Interconnection Study

Energy Technology Data Exchange (ETDEWEB)

Daniel, John P. [ABB Inc; Liu, Shu [ABB Inc; Ibanez, Eduardo [National Renewable Energy Laboratory; Pennock, Ken [AWS Truepower; Reed, Greg [University of Pittsburgh; Hanes, Spencer [Duke Energy

2014-07-30

The National Offshore Wind Energy Grid Interconnection Study (NOWEGIS) considers the availability and potential impacts of interconnecting large amounts of offshore wind energy into the transmission system of the lower 48 contiguous United States. A total of 54GW of offshore wind was assumed to be the target for the analyses conducted. A variety of issues are considered including: the anticipated staging of offshore wind; the offshore wind resource availability; offshore wind energy power production profiles; offshore wind variability; present and potential technologies for collection and delivery of offshore wind energy to the onshore grid; potential impacts to existing utility systems most likely to receive large amounts of offshore wind; and regulatory influences on offshore wind development. The technologies considered the reliability of various high-voltage ac (HVAC) and high-voltage dc (HVDC) technology options and configurations. The utility system impacts of GW-scale integration of offshore wind are considered from an operational steady-state perspective and from a regional and national production cost perspective.

Wind energy technology developments

DEFF Research Database (Denmark)

Madsen, Peter Hauge; Hansen, Morten Hartvig; Pedersen, Niels Leergaard

2014-01-01

turbine blades and towers are very large series-produced components, which costs and quality are strongly dependent on the manufacturing methods. The industrial wind energy sector is well developed in Denmark, and the competitive advantage of the Danish sector and the potential for job creation...

2012 wind technologies market report

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Barbose, Galen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Darghouth, Naim [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoen, Ben [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mills, Andrew [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Weaver, Samantha [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Porter, Kevin [Exeter Assoc., Columbia, MD (United States); Buckley, Michael [Exeter Assoc., Columbia, MD (United States); Fink, Sari [Exeter Assoc., Columbia, MD (United States); Oteri, Frank [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tegen, Suzanne [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-07-01

Annual wind power capacity additions in the United States achieved record levels in 2012, motivated by the then-planned expiration of federal tax incentives at the end of 2012 and recent improvements in the cost and performance of wind power technology. At the same time, even with a short-term extension of federal tax incentives now in place, the U.S. wind power industry is facing uncertain times. It will take time to rebuild the project pipeline, ensuring a slow year for new capacity additions in 2013. Continued low natural gas prices, modest electricity demand growth, and limited near-term demand from state renewables portfolio standards (RPS) have also put a damper on industry growth expectations. In combination with global competition within the sector, these trends continue to impact the manufacturing supply chain. What these trends mean for the medium to longer term remains to be seen, dictated in part by future natural gas prices, fossil plant retirements, and policy decisions, although recent declines in the price of wind energy have boost ed the prospects for future growth

Statistics of LES simulations of large wind farms

DEFF Research Database (Denmark)

Andersen, Søren Juhl; Sørensen, Jens Nørkær; Mikkelsen, Robert Flemming

2016-01-01

. The statistical moments appear to collapse and hence the turbulence inside large wind farms can potentially be scaled accordingly. The thrust coefficient is estimated by two different reference velocities and the generic CT expression by Frandsen. A reference velocity derived from the power production is shown...... to give very good agreement and furthermore enables the very good estimation of the thrust force using only the steady CT-curve, even for very short time samples. Finally, the effective turbulence inside large wind farms and the equivalent loads are examined....

2016 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan H. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-08-10

The U.S. Department of Energy (DOE)’s Wind Technologies Market Report provides an annual overview of trends in the U.S. wind power market. You can find the report, a presentation, and a data file on the Files tab, below. Additionally, several data visualizations are available in the Data Visualizations tab. Highlights of this year’s report include: -Wind power additions continued at a rapid clip in 2016: $13 billion was invested in new wind power plants in 2016. In 2016, wind energy contributed 5.6% of the nation’s electricity supply, more than 10% of total electricity generation in fourteen states, and 29% to 37% in three of those states—Iowa, South Dakota, and Kansas. -Bigger turbines are enhancing wind project performance: Increased blade lengths, in particular, have dramatically increased wind project capacity factors, one measure of project performance. For example, the average 2016 capacity factor among projects built in 2014 and 2015 was 42.6%, compared to an average of 32.1% among projects built from 2004 to 2011 and 25.4% among projects built from 1998 to 2001. -Low wind turbine pricing continues to push down installed project costs: Wind turbine prices have fallen from their highs in 2008, to $800–$1,100/kW. Overall, the average installed cost of wind projects in 2016 was $1,590/kW, down $780/kW from the peak in 2009 and 2010. -Wind energy prices remain low: After topping out at nearly 7¢/kWh for power purchase agreements (PPAs) executed in 2009, the national average price of wind PPAs has dropped to around 2¢/kWh—though this nationwide average is dominated by projects that hail from the lowest-priced Interior region of the country (such as Texas, Iowa, Oklahoma). These prices, which are possible in part due to federal tax support, compare favorably to the projected future fuel costs of gas-fired generation. -The supply chain continued to adjust to swings in domestic demand for wind equipment: Wind sector employment reached a new high of

Aeroelastic analysis of large horizontal wind turbine baldes?

Institute of Scientific and Technical Information of China (English)

Di TANG; Zhiliang LU; Tongqing GUO

2016-01-01

A nonlinear aeroelastic analysis method for large horizontal wind turbines is described. A vortex wake method and a nonlinear ?nite element method (FEM) are coupled in the approach. The vortex wake method is used to predict wind turbine aero-dynamic loads of a wind turbine, and a three-dimensional (3D) shell model is built for the rotor. Average aerodynamic forces along the azimuth are applied to the structural model, and the nonlinear static aeroelastic behaviors are computed. The wind rotor modes are obtained at the static aeroelastic status by linearizing the coupled equations. The static aeroelastic performance and dynamic aeroelastic responses are calculated for the NH1500 wind turbine. The results show that structural geometrical nonlinearities signi?cantly reduce displacements and vibration amplitudes of the wind turbine blades. Therefore, structural geometrical nonlinearities cannot be neglected both in the static aeroelastic analysis and dynamic aeroelastic analysis.

National Wind Technology Center sitewide, Golden, CO: Environmental assessment

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-11-01

The National Renewable Energy Laboratory (NREL), the nation`s primary solar and renewable energy research laboratory, proposes to expand its wind technology research and development program activities at its National Wind Technology Center (NWTC) near Golden, Colorado. NWTC is an existing wind energy research facility operated by NREL for the US Department of Energy (DOE). Proposed activities include the construction and reuse of buildings and facilities, installation of up to 20 wind turbine test sites, improvements in infrastructure, and subsequent research activities, technology testing, and site operations. In addition to wind turbine test activities, NWTC may be used to support other NREL program activities and small-scale demonstration projects. This document assesses potential consequences to resources within the physical, biological, and human environment, including potential impacts to: air quality, geology and soils, water resources, biological resources, cultural and historic resources, socioeconomic resources, land use, visual resources, noise environment, hazardous materials and waste management, and health and safety conditions. Comment letters were received from several agencies in response to the scoping and predecisional draft reviews. The comments have been incorporated as appropriate into the document with full text of the letters contained in the Appendices. Additionally, information from the Rocky Flats Environmental Technology Site on going sitewide assessment of potential environmental impacts has been reviewed and discussed by representatives of both parties and incorporated into the document as appropriate.

National Wind Technology Center sitewide, Golden, CO: Environmental assessment

International Nuclear Information System (INIS)

1996-11-01

The National Renewable Energy Laboratory (NREL), the nation's primary solar and renewable energy research laboratory, proposes to expand its wind technology research and development program activities at its National Wind Technology Center (NWTC) near Golden, Colorado. NWTC is an existing wind energy research facility operated by NREL for the US Department of Energy (DOE). Proposed activities include the construction and reuse of buildings and facilities, installation of up to 20 wind turbine test sites, improvements in infrastructure, and subsequent research activities, technology testing, and site operations. In addition to wind turbine test activities, NWTC may be used to support other NREL program activities and small-scale demonstration projects. This document assesses potential consequences to resources within the physical, biological, and human environment, including potential impacts to: air quality, geology and soils, water resources, biological resources, cultural and historic resources, socioeconomic resources, land use, visual resources, noise environment, hazardous materials and waste management, and health and safety conditions. Comment letters were received from several agencies in response to the scoping and predecisional draft reviews. The comments have been incorporated as appropriate into the document with full text of the letters contained in the Appendices. Additionally, information from the Rocky Flats Environmental Technology Site on going sitewide assessment of potential environmental impacts has been reviewed and discussed by representatives of both parties and incorporated into the document as appropriate

Wind energy technology development and diffusion. A case study of Inner Mongolia, China

Energy Technology Data Exchange (ETDEWEB)

Zhang Xiliang; Gu Shuhua; Liu Wenqiang; Lin Gan

1999-09-01

This report provides an overview of the diffusion of small household wind generators and development of wind farms in Inner Mongolia, China, with the emphasis on policy and institutional perspectives. It analyses the patterns of wind technology diffusion within social, economic, and environmental contexts and relates the diffusion of wind technology to institutional framework building and international investment and technology transfer. By examining the economics of windfarm development and analysing the role of alternative policy instruments, the major constraints of wind technology development are analysed and relevant policy recommendations are given. 12 refs., 3 figs., 9 tabs.

How neighbours of the first large Swiss wind farm perceive the wind turbines

International Nuclear Information System (INIS)

Droz, Y.; Mieville-Ott, V.; Monsutti, A.

2003-01-01

This report for the Swiss Federal Office of Energy presents the results of a study on the way the neighbours of the first large Swiss wind farm react on this particular neighbourhood. A survey involving 421 people showed that, as a general rule, the wind turbines are well accepted. However, it also showed that a transparent negotiation with the population during wind turbine project developpement is absolutely needed. Public acceptance also depends on the way the turbine arrays are aesthetically integrated in the landscape. The report is rounded up by recommendations for companies in charge of wind energy projects in order to minimize troubles with the concerned population. For example, financial compensation could be a suitable means when dealing with farmers

ANEMOS: Development of a next generation wind power forecasting system for the large-scale integration of onshore and offshore wind farms.

Science.gov (United States)

Kariniotakis, G.; Anemos Team

2003-04-01

offshore wind farms taking into account advances in marine meteorology (interaction between wind and waves, coastal effects). The benefits from the use of satellite radar images for modeling local weather patterns are investigated. A next generation forecasting software, ANEMOS, will be developed to integrate the various models. The tool is enhanced by advanced Information Communication Technology (ICT) functionality and can operate both in stand alone, or remote mode, or be interfaced with standard Energy or Distribution Management Systems (EMS/DMS) systems. Contribution: The project provides an advanced technology for wind resource forecasting applicable in a large scale: at a single wind farm, regional or national level and for both interconnected and island systems. A major milestone is the on-line operation of the developed software by the participating utilities for onshore and offshore wind farms and the demonstration of the economic benefits. The outcome of the ANEMOS project will help consistently the increase of wind integration in two levels; in an operational level due to better management of wind farms, but also, it will contribute to increasing the installed capacity of wind farms. This is because accurate prediction of the resource reduces the risk of wind farm developers, who are then more willing to undertake new wind farm installations especially in a liberalized electricity market environment.

IMPER: Characterization of the wind field over a large wind turbine rotor - final report; Improved performance

Energy Technology Data Exchange (ETDEWEB)

Schmidt Paulsen, U.; Wagner, R.

2012-01-15

A modern wind turbine rotor with a contemporary rotor size would easily with the tips penetrate the air between 116 m and 30 m and herby experience effects of different wind. With current rules on power performance measurements such as IEC 61400-121 the reference wind speed is measured at hub height, an oversimplification of the wind energy power over the rotor disk area is carried out. The project comprised a number of innovative and coordinated measurements on a full scale turbine with remote sensing technology and simulations on a 500 kW wind turbine for the effects of wind field characterization. The objective with the present report is to give a short overview of the different experiments carried out and results obtained within the final phase of this project. (Author)

Synthetic atmospheric turbulence and wind shear in large eddy simulations of wind turbine wakes

DEFF Research Database (Denmark)

Keck, Rolf-Erik; Mikkelsen, Robert Flemming; Troldborg, Niels

2014-01-01

, superimposed on top of a mean deterministic shear layer consistent with that used in the IEC standard for wind turbine load calculations. First, the method is evaluated by running a series of large-eddy simulations in an empty domain, where the imposed turbulence and wind shear is allowed to reach a fully...

Can Weather Radars Help Monitoring and Forecasting Wind Power Fluctuations at Large Offshore Wind Farms?

DEFF Research Database (Denmark)

Trombe, Pierre-Julien; Pinson, Pierre; Madsen, Henrik

2011-01-01

The substantial impact of wind power fluctuations at large offshore wind farms calls for the development of dedicated monitoring and prediction approaches. Based on recent findings, a Local Area Weather Radar (LAWR) was installed at Horns Rev with the aim of improving predictability, controlability...... and potentially maintenance planning. Additional images are available from a Doppler radar covering the same area. The parallel analysis of rain events detection and of regime sequences in wind (and power) fluctuations demonstrates the interest of employing weather radars for a better operation and management...... of offshore wind farms....

Harmonic Instability Source Identification in Large Wind Farms

DEFF Research Database (Denmark)

Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei

2017-01-01

A large-scale power electronics based power system like a wind farm introduces the passive and active impedances. The interactions between the active and passive impedances can lead to harmonic-frequency oscillations above the fundamental frequency, which can be called harmonic instability....... This paper presents an approach to identify which wind turbine and which bus has more contribution to the harmonic instability problems. In the approach, a wind farm is modeled as a Multi-Input Multi-Output (MIMO) dynamic system. The poles of the MIMO transfer matrix are used to predict the system...... instability and the eigenvalues sensitivity analysis in respect to the elements of the MIMO matrix locates the most influencing buses of the wind farm. Time-domain simulations in PSCAD software environment for a 400-MW wind farm validate that the presented approach is an effective tool to determine the main...

Canadian wind technology licensed for use in China

Energy Technology Data Exchange (ETDEWEB)

Anon.

2005-10-01

A collaboration between Calgary-based Sustainable Energy Technology Ltd. and the China Renewable Energy Technologies Delegation was discussed. Sustainable Energy Technology develops, manufactures and markets products for emerging alternative and renewable energy markets. The aim of the collaboration is to advance the development and commercialization of Darrieus type wind turbines for use in China and other markets around the world. Sustainable Energy will license its technology and expertise in advancing the Chinook 250 vertical axis wind turbine technology, beginning with the construction and testing of a commercial proto-type 250 kW turbine at a test site in southern Alberta. A memorandum of understanding was signed by Guo Shuyan on behalf of the China Renewable Energy Technologies Delegation. It was noted that Shuyan is currently vice chairman of the finance and economic committee of the National People's Congress and was also the executive director of the Three Gorges Project Construction Committee. Sustainable Energy is a leader in vertical axis wind turbines, and the Chinook 250 design was developed with support from Canada's National Research Council in 1999 in order to provide a simple, low-cost turbine that will reduce costly diesel fuel consumption for power generation on small islands in remote areas and throughout the developing world. The agreement with China is subject to approval by National Research Council.

Canadian wind technology licensed for use in China

International Nuclear Information System (INIS)

Anon.

2005-01-01

A collaboration between Calgary-based Sustainable Energy Technology Ltd. and the China Renewable Energy Technologies Delegation was discussed. Sustainable Energy Technology develops, manufactures and markets products for emerging alternative and renewable energy markets. The aim of the collaboration is to advance the development and commercialization of Darrieus type wind turbines for use in China and other markets around the world. Sustainable Energy will license its technology and expertise in advancing the Chinook 250 vertical axis wind turbine technology, beginning with the construction and testing of a commercial proto-type 250 kW turbine at a test site in southern Alberta. A memorandum of understanding was signed by Guo Shuyan on behalf of the China Renewable Energy Technologies Delegation. It was noted that Shuyan is currently vice chairman of the finance and economic committee of the National People's Congress and was also the executive director of the Three Gorges Project Construction Committee. Sustainable Energy is a leader in vertical axis wind turbines, and the Chinook 250 design was developed with support from Canada's National Research Council in 1999 in order to provide a simple, low-cost turbine that will reduce costly diesel fuel consumption for power generation on small islands in remote areas and throughout the developing world. The agreement with China is subject to approval by National Research Council

Review of Potential Wind Tunnel Balance Technologies

Science.gov (United States)

Burns, Devin E.; Williams, Quincy L.; Phillips, Ben D.; Commo, Sean A.; Ponder, Jonathon D.

2016-01-01

This manuscript reviews design, manufacture, materials, sensors, and data acquisition technologies that may benefit wind tunnel balances for the aerospace research community. Current state-of-the-art practices are used as the benchmark to consider advancements driven by researcher and facility needs. Additive manufacturing is highlighted as a promising alternative technology to conventional fabrication and has the potential to reduce both the cost and time required to manufacture force balances. Material alternatives to maraging steels are reviewed. Sensor technologies including piezoresistive, piezoelectric, surface acoustic wave, and fiber optic are compared to traditional foil based gages to highlight unique opportunities and shared challenges for implementation in wind tunnel environments. Finally, data acquisition systems that could be integrated into force balances are highlighted as a way to simplify the user experience and improve data quality. In summary, a rank ordering is provided to support strategic investment in exploring the technologies reviewed in this manuscript.

Generating wind fluctuations for Large Eddy Simulation inflow boundary condition

International Nuclear Information System (INIS)

Bekele, S.A.; Hangan, H.

2004-01-01

Large Eddy Simulation (LES) studies of flows over bluff bodies immersed in a boundary layer wind environment require instantaneous wind characteristics. The influences of the wind environment on the building pressure distribution are a well-established fact in the experimental study of wind engineering. Measured wind data of full or model scale are available only at a limited number of points. A method of obtaining instantaneous wind data at all mesh points of the inlet boundary for LES computation is necessary. Herein previous and new wind inflow generation techniques are presented. The generated wind data is then applied to a LES computation of a channel flow. The characteristics of the generated wind fluctuations in comparison to the measured data and the properties of the flow field computed from these two wind data are discussed. (author)

Large eddy simulation study of the kinetic energy entrainment by energetic turbulent flow structures in large wind farms

Science.gov (United States)

VerHulst, Claire; Meneveau, Charles

2014-02-01

In this study, we address the question of how kinetic energy is entrained into large wind turbine arrays and, in particular, how large-scale flow structures contribute to such entrainment. Previous research has shown this entrainment to be an important limiting factor in the performance of very large arrays where the flow becomes fully developed and there is a balance between the forcing of the atmospheric boundary layer and the resistance of the wind turbines. Given the high Reynolds numbers and domain sizes on the order of kilometers, we rely on wall-modeled large eddy simulation (LES) to simulate turbulent flow within the wind farm. Three-dimensional proper orthogonal decomposition (POD) analysis is then used to identify the most energetic flow structures present in the LES data. We quantify the contribution of each POD mode to the kinetic energy entrainment and its dependence on the layout of the wind turbine array. The primary large-scale structures are found to be streamwise, counter-rotating vortices located above the height of the wind turbines. While the flow is periodic, the geometry is not invariant to all horizontal translations due to the presence of the wind turbines and thus POD modes need not be Fourier modes. Differences of the obtained modes with Fourier modes are documented. Some of the modes are responsible for a large fraction of the kinetic energy flux to the wind turbine region. Surprisingly, more flow structures (POD modes) are needed to capture at least 40% of the turbulent kinetic energy, for which the POD analysis is optimal, than are needed to capture at least 40% of the kinetic energy flux to the turbines. For comparison, we consider the cases of aligned and staggered wind turbine arrays in a neutral atmospheric boundary layer as well as a reference case without wind turbines. While the general characteristics of the flow structures are robust, the net kinetic energy entrainment to the turbines depends on the presence and relative

Studies of Sub-Synchronous Oscillations in Large-Scale Wind Farm Integrated System

Science.gov (United States)

Yue, Liu; Hang, Mend

2018-01-01

With the rapid development and construction of large-scale wind farms and grid-connected operation, the series compensation wind power AC transmission is gradually becoming the main way of power usage and improvement of wind power availability and grid stability, but the integration of wind farm will change the SSO (Sub-Synchronous oscillation) damping characteristics of synchronous generator system. Regarding the above SSO problem caused by integration of large-scale wind farms, this paper focusing on doubly fed induction generator (DFIG) based wind farms, aim to summarize the SSO mechanism in large-scale wind power integrated system with series compensation, which can be classified as three types: sub-synchronous control interaction (SSCI), sub-synchronous torsional interaction (SSTI), sub-synchronous resonance (SSR). Then, SSO modelling and analysis methods are categorized and compared by its applicable areas. Furthermore, this paper summarizes the suppression measures of actual SSO projects based on different control objectives. Finally, the research prospect on this field is explored.

Determination of the Most Suitable Technology Transfer Strategy for Wind Turbines Using an Integrated AHP-TOPSIS Decision Model

Directory of Open Access Journals (Sweden)

A. Dinmohammadi

2017-05-01

Full Text Available The high-speed development of industrial products and goods in the world has caused “technology” to be considered as a crucial competitive advantage for most large organizations. In recent years, developing countries have considerably tended to promote their technological and innovative capabilities through importing high-tech equipment owned and operated by developed countries. There are currently a variety of solutions to transfer a particular technology from a developed country. The selection of the most profitable technology transfer strategy is a very complex decision-making problem for technology importers as it involves different technical, environmental, social, and economic aspects. In this study, a hybrid multiple-criteria decision making (MCDM model based on the analytic hierarchy process (AHP and the technique for order of preference by similarity to ideal solution (TOPSIS is proposed to evaluate and prioritise various technology transfer strategies for wind turbine systems. For this purpose, a number of criteria and sub-criteria are defined from the viewpoint of wind energy investors, wind turbine manufacturers, and wind farm operators. The relative importance of criteria and sub-criteria with respect to the ultimate goal are computed using the eigenvalue method and then, the technology transfer alternatives are ranked based on their relative closeness to the ideal solution. The model is finally applied to determine the most suitable wind turbine technology transfer strategy among four options of reverse engineering, technology skills training, turn-key contracts, and technology licensing for the renewable energy sector of Iran, and the results are compared with those obtained by classical decision-making models.

A large-scale view of Space Technology 5 magnetometer response to solar wind drivers.

Science.gov (United States)

Knipp, D J; Kilcommons, L M; Gjerloev, J; Redmon, R J; Slavin, J; Le, G

2015-04-01

In this data report we discuss reprocessing of the Space Technology 5 (ST5) magnetometer database for inclusion in NASA's Coordinated Data Analysis Web (CDAWeb) virtual observatory. The mission consisted of three spacecraft flying in elliptical orbits, from 27 March to 27 June 2006. Reprocessing includes (1) transforming the data into the Modified Apex Coordinate System for projection to a common reference altitude of 110 km, (2) correcting gain jumps, and (3) validating the results. We display the averaged magnetic perturbations as a keogram, which allows direct comparison of the full-mission data with the solar wind values and geomagnetic indices. With the data referenced to a common altitude, we find the following: (1) Magnetic perturbations that track the passage of corotating interaction regions and high-speed solar wind; (2) unexpectedly strong dayside perturbations during a solstice magnetospheric sawtooth oscillation interval characterized by a radial interplanetary magnetic field (IMF) component that may have enhanced the accompanying modest southward IMF; and (3) intervals of reduced magnetic perturbations or "calms," associated with periods of slow solar wind, interspersed among variable-length episodic enhancements. These calms are most evident when the IMF is northward or projects with a northward component onto the geomagnetic dipole. The reprocessed ST5 data are in very good agreement with magnetic perturbations from the Defense Meteorological Satellite Program (DMSP) spacecraft, which we also map to 110 km. We briefly discuss the methods used to remap the ST5 data and the means of validating the results against DMSP. Our methods form the basis for future intermission comparisons of space-based magnetometer data.

Value of flexibility in systems with large wind penetration

OpenAIRE

Silva , Vera

2010-01-01

The focus of this thesis is the quantification of the value of operation flexibility in systems with large penetration of wind generation. This begins with the quantification of the impact of wind generation (WG) uncertainty on the system's needs for frequency regulation and reserve. This is done by combing the stochastic behaviour of wind generation, demand uncertainty and generation outages. Two different approaches are compared to access the implications of using normal distribution approx...

Contribution to the chapter on wind power in: Energy technology perspectives 2008, IEA

Energy Technology Data Exchange (ETDEWEB)

Lemming, J.; Morthorst, P.E.; Clausen, Niels-Erik; Hjuler Jensen, P.

2009-01-15

Over the last 5 years the growth rate in wind energy has been as high as 30% an on average nearly 25% in all continents, and a considerable number of countries have very ambitious goals concerning their wind energy development, therefore it could be likely to cover as much as 20% of the world's electricity consumption by wind in 2030 and 35% in 2050, although on the shorter term growth is expected to take place mainly in Europe, USA and China. The market is maturing, therefore achieving more stable economies in the wind energy sector. As a result, better electrical grids suited for wind power are being developed and better planning tools as well as other frameworks, which benefit the market for installation of wind turbines, are being implemented across all wind energy countries. The cost of wind-generated electricity has fallen steadily for the last two decades, driven largely by technological advances, increased production levels and the use of larger turbines. Between 1985 and 2005, production costs energy from of wind turbines decreased by nearly 100% in 2006 prices. The price rises seen in last three years due to capacity problems in the industry are expected to stop, once supply system constraints are overcome. Onshore wind is considered commercial at sites with good wind resources and grid access. Cost reductions in both turbines and infrastructure are expected to bring investment costs to 0.88 mill. Euro/MW in 2030 and 0.8 mill. Euro/MW in 2050. On the other hand, offshore wind is in pre-commercial development phase. Considerable costs improvements are expected in all areas making costs go down to 1. 4 mill. Euro/MW in 2030 and 1.3 mill. Euro/MW in 2050. Priority RD and D areas to foster continued growth in wind power are to increase the value and reduce uncertainties. This will mean further cost reductions on longer terms, enabling large-scale use by improved grid integration and storage facilities and minimizing environmental impact. (au)

Boosting the adoption and the reliability of renewable energy sources: Mitigating the large-scale wind power intermittency through vehicle to grid technology

International Nuclear Information System (INIS)

Zhao, Yang; Noori, Mehdi; Tatari, Omer

2017-01-01

The integration of wind energy in the electricity sector and the adoption of electric vehicles in the transportation sector both have the potential to significantly reduce greenhouse gas emissions individually as well as in tandem with Vehicle-to-Grid technology. This study aims to evaluate the greenhouse gas emission savings of mitigating intermittency resulting from the introduction of wind power through Vehicle-to-Grid technologies, as well as the extent to which the marginal electricity consumption from charging an electric vehicle fleet may weaken this overall environmental benefit. To this end, the comparisons are conducted in seven independent system operator regions. The results indicate that, in most cases, the emission savings of a combination of wind power and Vehicle-to-Grid technology outweighs the additional emissions from marginal electricity generation for electric vehicles. In addition, the fluctuations in newly-integrated wind power could be balanced in the future using EVs and V2G technology, provided that a moderate portion of EV owners is willing to provide V2G services. On the other hand, such a combination is not favorable if the Vehicle-to-Grid service participation rate is less than 5% of all electric vehicle owners within a particular region. - Highlights: • The environmental benefit of vehicle to grid systems as grid stabilizer is analyzed. • Emission savings of vehicle to grid and impacts of electric vehicles are compared. • Seven independent system operator regions are studied. • Uncertainty and sensitivity analysis are performed through a Monte Carlo Simulation.

Innovative multi rotor wind turbine designs

Energy Technology Data Exchange (ETDEWEB)

Kale, S.A.; Sapali, S.N. [College of Engineering. Mechanical Engineering Dept, Pune (India)

2012-07-01

Among the renewable energy sources, today wind energy is the most recognized and cost effective. Developers and researchers in this sector are optimistic and continuously working innovatively to improve the technology. The wind power obtained is proportional to the swept area of wind turbine. The swept area is increased by using a single rotor of large diameter or multi rotors in array. The rotor size is growing continuously with mature technology. Multi rotor technology has a long history and the multi rotor concept persists in a variety of modern innovative systems but the concept has fallen out of consideration in mainstream design from the perception that is complex and unnecessary as very large single rotor units are now technically feasible. This work addresses the evaluation of different multi rotor wind turbine systems. These innovative wind turbines are evaluated on the basis of feasibility, technological advantages, security of expected power performance, cost, reliability, impact of innovative system, comparison with existing wind turbine design. The findings of this work will provide guidelines for the practical and economical ways for further research on the multi rotor wind turbines. (Author)

Modelling and measurements of wakes in large wind farms

DEFF Research Database (Denmark)

Barthelmie, Rebecca Jane; Rathmann, Ole; Frandsen, Sten Tronæs

2007-01-01

The paper presents research conducted in the Flow workpackage of the EU funded UPWIND project which focuses on improving models of flow within and downwind of large wind farms in complex terrain and offshore. The main activity is modelling the behaviour of wind turbine wakes in order to improve...

China's wind power industry: Policy support, technological achievements, and emerging challenges

International Nuclear Information System (INIS)

Wang, Zhongying; Qin, Haiyan; Lewis, Joanna I.

2012-01-01

Since 2005 the Chinese wind power technology industry has developed rapidly, with China becoming the largest installer of wind power capacity in the world in 2010. This paper reviews the policy system implemented in China to support the wind power industry, centered on China's 2005 Renewable Energy Law. It examines the industry's achievements over the past two decades, including the development of wind power technology and equipment, the utilization of China's wind power resources, and the cost reductions achieved. It then explores the obstacles affecting the ongoing sustainability of the Chinese wind industry, including regulatory barriers, grid integration challenges, and challenges to continued technological innovation. It recommends that integration challenges be addressed through policy reforms, establishing interconnection standards, and creating predictability with forecasting and storage; that market signals be established with long-term development goals and pricing reforms; and that industry limitations be addressed with targeted R and D, improved wind resource assessment and transparency, domestic and international collaborations, and the cultivation of a skilled workforce. - Highlights: ► Review the policy system and the achievements of Chinese wind industry. ► Analyze the obstacles affecting the sustainability of the industry. ► Provide recommendations for how China can address these obstacles.

Simulations of large winds and wind shears induced by gravity wave breaking in the mesosphere and lower thermosphere (MLT) region

OpenAIRE

X. Liu; X. Liu; J. Xu; H.-L. Liu; J. Yue; W. Yuan

2014-01-01

Using a fully nonlinear two-dimensional (2-D) numerical model, we simulated gravity waves (GWs) breaking and their contributions to the formation of large winds and wind shears in the mesosphere and lower thermosphere (MLT). An eddy diffusion coefficient is used in the 2-D numerical model to parameterize realistic turbulent mixing. Our study shows that the momentum deposited by breaking GWs accelerates the mean wind. The resultant large background wind increases the GW's app...

Perspectives of China's wind energy development

Institute of Scientific and Technical Information of China (English)

He Dexin; Wang Zhongying

2009-01-01

Wind energy is a kind of clean renewable energy, which is also relatively mature in technology, with large-scale development conditions and prospect for the commercialization. The development of wind energy is a systematic project, involving policy, law, technology, economy, society, environment, education and other aspects. The relation-ship among all the aspects should be well treated and coordinated. This paper has discussed the following relationships which should be well coordinated: relationship between wind resources and wind energy development, relationship be-tween the wind turbine generator system and the components, relationship between wind energy technology and wind en-ergy industry, relationship between off-grid wind power and grid-connected wind power, relationship between wind farm and the power grid, relationship between onshore wind power and offshore wind power, relationship between wind energy and other energies, relationship between technology introduction and self-innovation, relationship among foreign-funded, joint ventured and domestic-funded enterprises and relationship between the government guidance and the market regula-tion, as well as giving out some suggestions.

2010 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Exeter Associates; National Renewable Energy Laboratory; Energetics Incorporated; Wiser, Ryan; Bolinger, Mark; Barbose, Galen; Darghouth, Naim; Hoen, Ben; Mills, Andrew; Seel, Joachim; Porter, Kevin; Buckley, Michael; Fink, Sari; Oteri, Frank; Raymond, Russell

2011-06-27

The U.S. wind power industry experienced a trying year in 2010, with a significant reduction in new builds compared to both 2008 and 2009. The delayed impact of the global financial crisis, relatively low natural gas and wholesale electricity prices, and slumping overall demand for energy countered the ongoing availability of existing federal and state incentives for wind energy deployment. The fact that these same drivers did not impact capacity additions in 2009 can be explained, in part, by the 'inertia' in capital-intensive infrastructure investments: 2009 capacity additions were largely determined by decisions made prior to the economy-wide financial crisis that was at its peak in late 2008 and early 2009, whereas decisions on 2010 capacity additions were often made at the height of the financial crisis. Cumulative wind power capacity still grew by a healthy 15% in 2010, however, and most expectations are for moderately higher wind power capacity additions in 2011 than witnessed in 2010, though those additions are also expected to remain below the 2009 high.

Description and evaluation of foreign wind turbine technology

International Nuclear Information System (INIS)

1995-06-01

It is stated that sales of Danish-manufactured wind turbines abroad are decreasing due to an increase in production, marketing and technology research in other countries. The aim was to give an account of this international development which could form the basis for the future strategies of the Danish Wind turbine industry. The study is based on a survey of relevant literature, interviews with experts on the subject and the collection of the latest data. The survey is limited to wind turbines with a larger capacity than 50 kW. Recommendations are given as to how to conserve and develop the market for Danish wind turbines. (AB) 17 refs

Development of large scale wind energy conservation system. Development of large scale wind energy conversion system; Ogata furyoku hatsuden system no kaihatsu. Ogata furyoku hatsuden system no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Takita, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

1994-12-01

Described herein are the results of the FY1994 research program for development of large scale wind energy conversion system. The study on technological development of key components evaluates performance of, and confirms reliability and applicability of, hydraulic systems centered by those equipped with variable pitch mechanisms and electrohydraulic servo valves that control them. The study on blade conducts fatigue and crack-propagation tests, which show that the blades developed have high strength. The study on speed-increasing gear conducts load tests, confirming the effects of reducing vibration and noise by modification of the gear teeth. The study on NACELLE cover conducts vibration tests to confirm its vibration characteristics, and analyzes three-dimensional vibration by the finite element method. Some components for a 500kW commercial wind mill are fabricated, including rotor heads, variable pitch mechanisms, speed-increasing gears, YAW systems, and hydraulic control systems. The others fabricated include a remote supervisory control system for maintenance, system to integrate the wind mill into a power system, and electrical control devices in which site conditions, such as atmospheric temperature and lightening, are taken into consideration.

Collision risk of birds with modern large wind turbines

NARCIS (Netherlands)

Krijgsveld, K.L.; Akershoek, K.; Schenk, F.; Dijk, van F.; Dirksen, J.

2009-01-01

We studied collision rate of birds with modern, large 1.65 MW wind turbines in three wind farms in The Netherlands during three months in autumn and winter. Collision rate, after correction for retrieval and disappearance rate, was 0.08 birds per turbine per day on average (range 0.05-0.19).

Modelling and measurements of wakes in large wind farms

International Nuclear Information System (INIS)

Barthelmie, R J; Rathmann, O; Frandsen, S T; Hansen, K S; Politis, E; Prospathopoulos, J; Rados, K; Cabezon, D; Schlez, W; Phillips, J; Neubert, A; Schepers, J G; Pijl, S P van der

2007-01-01

The paper presents research conducted in the Flow workpackage of the EU funded UPWIND project which focuses on improving models of flow within and downwind of large wind farms in complex terrain and offshore. The main activity is modelling the behaviour of wind turbine wakes in order to improve power output predictions

Tall towers for large wind turbines. Report from Vindforsk project V-342

Energy Technology Data Exchange (ETDEWEB)

Engstroem, Staffan; Lyrner, Tomas; Hassanzadeh, Manouchehr; Stalin, Thomas; Johansson, John

2010-07-15

joints both longitudinally and laterally. Such a tower is transported as the separate cut, bent, drilled and painted steel plates, which are assembled at the turbine site. Also pretensioned concrete towers have a long history in wind power, starting with in-situ built slip formed towers. Today most concrete towers are assembled from prefabricated elements, cast in sizes allowing road transportation. The advantages of the concrete towers are concentrated to the lower parts, which are capable of absorbing large moments in an economical way. Therefore hybrid towers are appearing on the market, with a concrete part for the lower section and a conventional steel shell tower for the upper. From the present study one can draw a quite firm conclusion that hybrid towers generally are more economical than pure concrete ones. Due to the very large base width, lattice towers reveal the lowest weights and investments of all towers. The advantages are counteracted by disadvantages that may be equally strong. The number of bolts is very high and they need periodic checking. The dynamic properties are hard to control. During icing conditions large accumulation of ice in extreme cases may endanger the turbine. An acceptable level of safety for the maintenance personnel may be hard to maintain. And finally the visual qualities are controversial. Wood has been used as a construction material for wind turbine blades for decades, but only recently considered for wind turbine towers. This may seem strange, since towers should be a less demanding application than blades. Wood is also in general known to be an economical construction material resistant to fatigue and buckling. The so far only large wind turbine tower of wood is designed by a German company for a 1,5 MW wind turbine. In this report the wooden towers were studied less extensively than the others, due to the less developed and known technology especially regarding joints. From the study one can draw a general conclusion that it is

Barriers to renewable energy development: A case study of large-scale wind energy in Saskatchewan, Canada

International Nuclear Information System (INIS)

Richards, Garrett; Noble, Bram; Belcher, Ken

2012-01-01

Renewable energy is receiving increased attention as a viable alternative to non-renewable electrical generation, however, meeting global energy demands will require a more ambitious renewable energy program than is currently the case. There have been several reviews of potential technological, economic, social, or public barriers and solutions to renewable energy investment. Although important, there is also need for multi-dimensional analyses of these barriers and identification of the most significant underlying barriers if viable solutions are to be developed. In this paper we apply a theoretical framework to examine stakeholder's perceptions and understanding of the barriers to wind energy development in Saskatchewan, Canada. We identify and examine the most significant underlying barriers to investment in renewable energy and the interactions between those barriers. Results show a number of perceived barriers to wind energy investment, however, these barriers can be explained in large part by knowledge barriers, if not disagreement over whether the current level of investment in wind energy is sufficient. We show that barriers to renewable energy cannot be explained solely by technological, social, political, or economic factors in isolation, and that a multi-dimensional approach, identifying and explaining the underlying sources of these barriers, is necessary to develop viable solutions. - Highlights: ► Meeting future wind energy objectives requires an ambitious investment program. ► A framework is applied to identify and explain perceived barriers to wind energy. ► Stakeholders perceived technological and political barriers as the most significant. ► These could be explained by knowledge barriers and complacency with the status quo. ► Even with additional investment these underlying barriers will constrain progress.

Wind Energy Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Ma, Ke

2017-01-01

transmission networks at the scale of hundreds of megawatts. As its level of grid penetration has begun to increase dramatically, wind power is starting to have a significant impact on the operation of the modern grid system. Advanced power electronics technologies are being introduced to improve......Wind power now represents a major and growing source of renewable energy. Large wind turbines (with capacities of up to 6-8 MW) are widely installed in power distribution networks. Increasing numbers of onshore and offshore wind farms, acting as power plants, are connected directly to power...... the characteristics of the wind turbines, and make them more suitable for integration into the power grid. Meanwhile, there are some emerging challenges that still need to be addressed. This paper provides an overview and discusses some trends in the power electronics technologies used for wind power generation...

Harmonic Mitigation Methods in Large Offshore Wind Power Plants

DEFF Research Database (Denmark)

Kocewiak, Łukasz Hubert; Chaudhary, Sanjay; Hesselbæk, Bo

2013-01-01

Various sources of harmonic problems in large wind power plants (WPPs) and optimized harmonic mitigation methods are presented in this paper. The harmonic problems such as sources of harmonic emission and amplification as well as harmonic stability are identified. Also modern preventive...... and remedial harmonic mitigation methods in terms of passive and active filtering are described. It is shown that WPP components such as long HVAC cables and park transformers can introduce significant low-frequency resonances which can affect wind turbine control system operation and overall WPP stability...... as well as amplification of harmonic distortion. It is underlined that there is a potential in terms of active filtering in modern grid-side converters in e.g. wind turbines, STATCOMs or HVDC stations utilized in modern large WPPs. It is also emphasized that the grid-side converter controller should...

Impact of Wind Shear and Tower Shadow Effects on Power System with Large Scale Wind Power Penetration

DEFF Research Database (Denmark)

Hu, Weihao; Su, Chi; Chen, Zhe

2011-01-01

presents a simulation model of a variable speed wind farm with permanent magnet synchronous generators (PMSGs) and fullscale back-to-back converters in the simulation tool of DIgSILENT/PowerFactory. In this paper, the impacts of wind shear and tower shadow effects on the small signal stability of power......Grid connected wind turbines are fluctuating power sources due to wind speed variations, the wind shear and the tower shadow effects. The fluctuating power may be able to excite the power system oscillation at a frequency close to the natural oscillation frequency of a power system. This paper...... systems with large scale wind power penetrations are investigated during continuous operation based on the wind turbine model and the power system model....

Optimal control of energy extraction in LES of large wind farms

Science.gov (United States)

Meyers, Johan; Goit, Jay; Munters, Wim

2014-11-01

We investigate the use of optimal control combined with Large-Eddy Simulations (LES) of wind-farm boundary layer interaction for the increase of total energy extraction in very large ``infinite'' wind farms and in finite farms. We consider the individual wind turbines as flow actuators, whose energy extraction can be dynamically regulated in time so as to optimally influence the turbulent flow field, maximizing the wind farm power. For the simulation of wind-farm boundary layers we use large-eddy simulations in combination with an actuator-disk representation of wind turbines. Simulations are performed in our in-house pseudo-spectral code SP-Wind. For the optimal control study, we consider the dynamic control of turbine-thrust coefficients in the actuator-disk model. They represent the effect of turbine blades that can actively pitch in time, changing the lift- and drag coefficients of the turbine blades. In a first infinite wind-farm case, we find that farm power is increases by approximately 16% over one hour of operation. This comes at the cost of a deceleration of the outer layer of the boundary layer. A detailed analysis of energy balances is presented, and a comparison is made between infinite and finite farm cases, for which boundary layer entrainment plays an import role. The authors acknowledge support from the European Research Council (FP7-Ideas, Grant No. 306471). Simulations were performed on the computing infrastructure of the VSC Flemish Supercomputer Center, funded by the Hercules Foundation and the Flemish Govern.

Future wind deployment scenarios for South Africa

CSIR Research Space (South Africa)

Wright, Jarrad G

2017-11-01

Full Text Available understood wind (and solar) resource in South Africa combined with large geographical land-area and technology cost reductions globally and domestically for wind and solar photovoltaics (PV) has made these technologies more than competitive with alternatives...

Federal Wind Energy Program. Program summary. [USA

Energy Technology Data Exchange (ETDEWEB)

None

1978-01-01

The objective of the Federal Wind Energy Program is to accelerate the development of reliable and economically viable wind energy systems and enable the earliest possible commercialization of wind power. To achieve this objective for small and large wind systems requires advancing the technology, developing a sound industrial technology base, and addressing the non-technological issues which could deter the use of wind energy. This summary report outlines the projects being supported by the program through FY 1977 toward the achievement of these goals. It also outlines the program's general organization and specific program elements.

Wind farm density and harvested power in very large wind farms: A low-order model

Science.gov (United States)

Cortina, G.; Sharma, V.; Calaf, M.

2017-07-01

In this work we create new understanding of wind turbine wakes recovery process as a function of wind farm density using large-eddy simulations of an atmospheric boundary layer diurnal cycle. Simulations are forced with a constant geostrophic wind and a time varying surface temperature extracted from a selected period of the Cooperative Atmospheric Surface Exchange Study field experiment. Wind turbines are represented using the actuator disk model with rotation and yaw alignment. A control volume analysis around each turbine has been used to evaluate wind turbine wake recovery and corresponding harvested power. Results confirm the existence of two dominant recovery mechanisms, advection and flux of mean kinetic energy, which are modulated by the background thermal stratification. For the low-density arrangements advection dominates, while for the highly loaded wind farms the mean kinetic energy recovers through fluxes of mean kinetic energy. For those cases in between, a smooth balance of both mechanisms exists. From the results, a low-order model for the wind farms' harvested power as a function of thermal stratification and wind farm density has been developed, which has the potential to be used as an order-of-magnitude assessment tool.

HFSB-seeding for large-scale tomographic PIV in wind tunnels

Science.gov (United States)

Caridi, Giuseppe Carlo Alp; Ragni, Daniele; Sciacchitano, Andrea; Scarano, Fulvio

2016-12-01

A new system for large-scale tomographic particle image velocimetry in low-speed wind tunnels is presented. The system relies upon the use of sub-millimetre helium-filled soap bubbles as flow tracers, which scatter light with intensity several orders of magnitude higher than micron-sized droplets. With respect to a single bubble generator, the system increases the rate of bubbles emission by means of transient accumulation and rapid release. The governing parameters of the system are identified and discussed, namely the bubbles production rate, the accumulation and release times, the size of the bubble injector and its location with respect to the wind tunnel contraction. The relations between the above parameters, the resulting spatial concentration of tracers and measurement of dynamic spatial range are obtained and discussed. Large-scale experiments are carried out in a large low-speed wind tunnel with 2.85 × 2.85 m2 test section, where a vertical axis wind turbine of 1 m diameter is operated. Time-resolved tomographic PIV measurements are taken over a measurement volume of 40 × 20 × 15 cm3, allowing the quantitative analysis of the tip-vortex structure and dynamical evolution.

Study of large-scale vertical axis wind turbine wake through numerical modelling and fullscale experiments

DEFF Research Database (Denmark)

Immas, Alexandre; Kluczewska-Bordier, Joanna; Beneditti, Pascal

Offshore wind capacity is increasing exponentially over the years in Europe, taking advantage of the strong winds available over the ocean and of the political incentives to reduce greenhouse gases. The technology is however not yet competitive when compared to fossil fuels or onshore wind. One k...... horizontal axis wind turbine wind farm....... improvement that could make offshore wind more attractive is the reduction of the wake effect [1]. The latter corresponds to the velocity deficit generated by each wind turbine wake which affects the production of the others. This effect accounts for approximately 10% of the energy losses for a typical......Offshore wind capacity is increasing exponentially over the years in Europe, taking advantage of the strong winds available over the ocean and of the political incentives to reduce greenhouse gases. The technology is however not yet competitive when compared to fossil fuels or onshore wind. One key...

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

Wind Power Technologies FY 2017 Budget At-A-Glance

Energy Technology Data Exchange (ETDEWEB)

None, None

2016-03-01

The Wind Program accelerates U.S. deployment of clean, affordable, and reliable domestic wind power through research, development, and demonstration activities. These advanced technology investments directly contribute to the goals for the United States to generate 80% of the nation’s electricity from clean, carbon-free energy sources by 2035; reduce carbon emissions 26%-28% below 2005 levels by 2025; and reduce carbon emissions 80% by 2050 by reducing costs and increasing performance of wind energy systems.

Transportation of Large Wind Components: A Permitting and Regulatory Review

Energy Technology Data Exchange (ETDEWEB)

Levine, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cook, Jeff [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-09-01

This report summarizes permitting and regulatory issues associated with transporting wind turbine blades, towers, and nacelles as well as large transformers (wind components). These wind components are commonly categorized as oversized and overweight (OSOW) and require specific permit approvals from state and local jurisdictions. The report was developed based on a Quadrennial Energy Review (QER) recommendation on logistical requirements for the transportation of 'oversized or high-consequence energy materials, equipment, and components.'

Integration of wind power in the liberalized Dutch electricity market

NARCIS (Netherlands)

Ummels, B.C.; Gibescu, M.; Kling, W.L.; Paap, G.C.

2006-01-01

Wind power is becoming a large-scale electricity generation technology in a number of European countries, including the Netherlands.Owing to the variability and unpredictability of wind power production, large-scale wind power can be foreseen to have large consequences for balancing generation and

Wind energy technology : from the past to the future; 20 seiki ni okeru furyoku riyo gijutsu no henkan. Furyoku hatsuden : kako kara mirai e

Energy Technology Data Exchange (ETDEWEB)

Ushiyama, I. [Ashikaga Institute of Technology, Tochigi (Japan)

2000-01-20

Windmills are one of the oldest prime movers and have been used for more than 700 years in Europe. The transition from low speed windmills for grain grinding and water pumping to high speed wind turbines for electric power generation had occurred at first, reviews the windmill technologies and the researchers before 20{sup th} century. Then describes the back ground of how the wind power generator has existed and how the four pioneers developed their wind power generator. The historical developments of windmills to wind turbines in this century are studied focusing mainly on Danish activities. Then, the effort of the development of large wind turbine such as Smith-Putnum's first MW machine in U.S.A. and other mammoth machine concept are introduced. The new concept machines such as Savonius and Darrieus wind turbines in 1920s to 1930s are also explained. Finally, the novel technologies of wind turbine covering larger machines, variable speed generators, special wing sections for wind turbines, theoretical analysis method of wind turbine performance, offshore wind turbines, and wind turbine control technologies are stated. (author)

Systematic framework for the efficient integration of wind technologies into buildings

Directory of Open Access Journals (Sweden)

Ashraf A. ELMokadem

2016-03-01

Full Text Available The renewed interest that is being paid by architects, project developers and local governments to integrate wind turbines with buildings is mainly required a framework to unify much data, criteria and variables to ease the design process to many architects. Therefore, this paper introduces and elaborates the systematic framework towards the efficient integration of wind technologies into new building. Moreover, it evaluates the framework effectiveness by comparing the current status of wind technologies integration into a building with the suggested status if the framework is followed.

Fixed-speed active-stall wind turbines in offshore applications

DEFF Research Database (Denmark)

Akhmatov, Vladislav; Nielsen, Arne Hejde

2005-01-01

A large offshore wind farm in the East Danish power system was commissioned in 2003 at Rodsand. The power capacity of the wind farm is 165 MW divided between 72 wind turbines. For this large offshore application, robust and well-known wind technology has been chosen in the form of fixed-speed, ac...

An improved market penetration model for wind energy technology forecasting

International Nuclear Information System (INIS)

Lund, P.D.

1995-01-01

An improved market penetration model with application to wind energy forecasting is presented. In the model, a technology diffusion model and manufacturing learning curve are combined. Based on a 85% progress ratio that was found for European wind manufactures and on wind market statistics, an additional wind power capacity of ca 4 GW is needed in Europe to reach a 30 % price reduction. A full breakthrough to low-cost utility bulk power markets could be achieved at a 24 GW level. (author)

An improved market penetration model for wind energy technology forecasting

Energy Technology Data Exchange (ETDEWEB)

Lund, P D [Helsinki Univ. of Technology, Espoo (Finland). Advanced Energy Systems

1996-12-31

An improved market penetration model with application to wind energy forecasting is presented. In the model, a technology diffusion model and manufacturing learning curve are combined. Based on a 85% progress ratio that was found for European wind manufactures and on wind market statistics, an additional wind power capacity of ca 4 GW is needed in Europe to reach a 30 % price reduction. A full breakthrough to low-cost utility bulk power markets could be achieved at a 24 GW level. (author)

An improved market penetration model for wind energy technology forecasting

Energy Technology Data Exchange (ETDEWEB)

Lund, P.D. [Helsinki Univ. of Technology, Espoo (Finland). Advanced Energy Systems

1995-12-31

An improved market penetration model with application to wind energy forecasting is presented. In the model, a technology diffusion model and manufacturing learning curve are combined. Based on a 85% progress ratio that was found for European wind manufactures and on wind market statistics, an additional wind power capacity of ca 4 GW is needed in Europe to reach a 30 % price reduction. A full breakthrough to low-cost utility bulk power markets could be achieved at a 24 GW level. (author)

Optimal Selection of AC Cables for Large Scale Offshore Wind Farms

DEFF Research Database (Denmark)

Hou, Peng; Hu, Weihao; Chen, Zhe

2014-01-01

The investment of large scale offshore wind farms is high in which the electrical system has a significant contribution to the total cost. As one of the key components, the cost of the connection cables affects the initial investment a lot. The development of cable manufacturing provides a vast...... and systematical way for the optimal selection of cables in large scale offshore wind farms....

A real-scale helical coil winding trial of the Large Helical Device

International Nuclear Information System (INIS)

Senba, T.; Yamamoto, T.; Tamaki, T.; Asano, K.; Suzuki, S.; Yamauchi, T.; Uchida, K.; Nakanishi, K.; Yamagiwa, T.; Suzuki, S.; Miyoshi, R.; Sasa, H.; Watanabe, S.; Tatemura, M.; Hatada, N.; Yamaguchi, S.; Imagawa, S.; Yanagi, N.; Satow, T.; Yamamoto, J.; Motojima, O.

1995-01-01

A real-scale helical coil winding trial of the Large Helical Device (LHD) has been conducted for a study of coil winding configuration and winding methods and for exhibiting the state of the art. It includes construction and test run of a specifically designed winding machine and development of various manufacturing methods for accurate coil winding. It has been carried out in Hitachi Works before in situ winding, and has provided much needed engineering data for construction of the LHD. (orig.)

Videometric research on deformation measurement of large-scale wind turbine blades

Institute of Scientific and Technical Information of China (English)

无

2011-01-01

Utilization of wind energy is a promising way to generate power,and wind turbine blades play a key role in collecting the wind energy effectively.This paper attempts to measure the deformation parameter of wind turbine blades in mechanics experiments using a videometric method. In view that the blades experience small buckling deformation and large integral deformation simultaneously, we proposed a parallel network measurement(PNM) method including the key techniques such as camera network construction,c...

Harnessing the Power of Wind Technology

Science.gov (United States)

Dotson, Tawny M.

2009-01-01

"Where the wind comes sweepin' down the plain" is more than just a song lyric for Oklahoma's career and technical education community. It's the acknowledgement of an untapped natural resource that has the potential to translate into both energy independence for the country and jobs for the state. Statewide, technology center instructors…

Final Technical Report: The Incubation of Next-Generation Radar Technologies to Lower the Cost of Wind Energy

Energy Technology Data Exchange (ETDEWEB)

Schroeder, John [Texas Tech Univ., Lubbock, TX (United States); Hirth, Brian [Texas Tech Univ., Lubbock, TX (United States); Guynes, Jerry [Texas Tech Univ., Lubbock, TX (United States)

2017-03-15

The National Wind Institute (NWI) at Texas Tech University (TTU) has had an impressive and well documented 46-year history of wind related research activities (http://www.depts.ttu.edu/nwi/). In 2011 with funding from the United States Department of Energy (DOE), an NWI team applied radar technologies and techniques to document the complex flows occurring across a wind plant. The resulting efforts yielded measurements that exceeded the capabilities of commercial lidar technologies with respect to maximum range, range resolution and scan speed. The NWI team was also the first to apply dual-Doppler synthesis and objective analysis techniques to resolve the full horizontal wind field (i.e. not just the line-of-sight wind speeds) to successfully define turbine inflow and wake flows across large segments of wind plants. While these successes advanced wind energy interests, the existing research radar platforms were designed to serve a diversity of meteorological applications, not specifically wind energy. Because of this broader focus and the design choices made during their development, the existing radars experienced technical limitations that inhibited their commercial viability and wide spread adoption. This DOE project enabled the development of a new radar prototype specifically designed for the purpose of documenting wind farm complex flows. Relative to other “off the shelf” radar technologies, the specialized transmitter and receiver chains were specifically designed to enhance data availability in non-precipitating atmospheres. The new radar prototype was integrated at TTU using components from various suppliers across the world, and installed at the Reese Technology Center in May 2016. Following installation, functionality and performance testing were completed, and subsequent comparative analysis indicated that the new prototype greatly enhances data availability by a factor of 3.5-50 in almost all atmospheric conditions. The new prototype also provided

The viability of balancing wind generation with large scale energy storage

International Nuclear Information System (INIS)

Nyamdash, Batsaikhan; Denny, Eleanor; O'Malley, Mark

2010-01-01

This paper studies the impact of combining wind generation and dedicated large scale energy storage on the conventional thermal plant mix and the CO 2 emissions of a power system. Different strategies are proposed here in order to explore the best operational strategy for the wind and storage system in terms of its effect on the net load. Furthermore, the economic viability of combining wind and large scale storage is studied. The empirical application, using data for the Irish power system, shows that combined wind and storage reduces the participation of mid-merit plants and increases the participation of base-load plants. Moreover, storage negates some of the CO 2 emissions reduction of the wind generation. It was also found that the wind and storage output can significantly reduce the variability of the net load under certain operational strategies and the optimal strategy depends on the installed wind capacity. However, in the absence of any supporting mechanism none of the storage devices were economically viable when they were combined with the wind generation on the Irish power system. - Research Highlights: → Energy storage would displace the peaking and mid-merit plants generations by the base-load plants generations. Energy storage may negate the CO 2 emissions reduction that is due to the increased wind generations. →Energy storage reduces the variation of the net load. →Under certain market conditions, merchant type energy storage is not viable.

Pilot project wind power - Large scale wind power in northern Sweden; Pilotprojekt vindkraft - Storskalig vindkraft i norra Sverige

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

The Swedish Energy Agency granted 2009-04-20 Svevind AB financial aid to implement {sup P}ilot project wind power- Large scale wind power in northern Sweden{sup .} The purpose of the aid is to implement pilot sub-projects in wind power, to to increase knowledge for the larger establishments. The Energy Agency said in its decision that the projects Dragaliden and Gabriel Mountain is of 'great importance for future large-scale development of wind power in Sweden'. The special conditions prevailing in the project, forest environment and cold climate, gives the possibility of studies of wind turbines on birds, reindeer herding and hunting and the more technical aspects, such as de-icing and obstacle lighting. The objectives of the project, in addition to the construction and operation of 32 wind turbines, has been to include evaluating the permit process, studying the social effects around the wind power, to study the impact on small game hunting, perform tests of the de-icing system, investigate impacts on reindeer herding and explain the outcome of the project-generated rural funds. Some of the above sub-projects have been completed, which are reported in this report. For the sub-projects still in progress, the report presents the results to date, until the completion.

Wind power integration into the automatic generation control of power systems with large-scale wind power

DEFF Research Database (Denmark)

Basit, Abdul; Hansen, Anca Daniela; Altin, Müfit

2014-01-01

Transmission system operators have an increased interest in the active participation of wind power plants (WPP) in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC......) of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs) and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described...... and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different...

Large Eddy Simulation of Turbulent Flows in Wind Energy

DEFF Research Database (Denmark)

Chivaee, Hamid Sarlak

This research is devoted to the Large Eddy Simulation (LES), and to lesser extent, wind tunnel measurements of turbulent flows in wind energy. It starts with an introduction to the LES technique associated with the solution of the incompressible Navier-Stokes equations, discretized using a finite......, should the mesh resolution, numerical discretization scheme, time averaging period, and domain size be chosen wisely. A thorough investigation of the wind turbine wake interactions is also conducted and the simulations are validated against available experimental data from external sources. The effect...... Reynolds numbers, and thereafter, the fully-developed infinite wind farm boundary later simulations are performed. Sources of inaccuracy in the simulations are investigated and it is found that high Reynolds number flows are more sensitive to the choice of the SGS model than their low Reynolds number...

2014–2015 Offshore Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Aaron Smith, Tyler Stehly, Walt Musial

2015-09-30

This report provides data and analysis to assess the status of the U.S. offshore wind industry through June 30, 2015. It builds on the foundation laid by the Navigant Consortium, which produced three market reports between 2012 and 2014. The report summarizes domestic and global market developments, technology trends, and economic data to help U.S. offshore wind industry stakeholders, including policymakers, regulators, developers, financiers, and supply chain participants, to identify barriers and opportunities.

Demonstrating a new framework for the comparison of environmental impacts from small- and large-scale hydropower and wind power projects.

Science.gov (United States)

Bakken, Tor Haakon; Aase, Anne Guri; Hagen, Dagmar; Sundt, Håkon; Barton, David N; Lujala, Päivi

2014-07-01

Climate change and the needed reductions in the use of fossil fuels call for the development of renewable energy sources. However, renewable energy production, such as hydropower (both small- and large-scale) and wind power have adverse impacts on the local environment by causing reductions in biodiversity and loss of habitats and species. This paper compares the environmental impacts of many small-scale hydropower plants with a few large-scale hydropower projects and one wind power farm, based on the same set of environmental parameters; land occupation, reduction in wilderness areas (INON), visibility and impacts on red-listed species. Our basis for comparison was similar energy volumes produced, without considering the quality of the energy services provided. The results show that small-scale hydropower performs less favourably in all parameters except land occupation. The land occupation of large hydropower and wind power is in the range of 45-50 m(2)/MWh, which is more than two times larger than the small-scale hydropower, where the large land occupation for large hydropower is explained by the extent of the reservoirs. On all the three other parameters small-scale hydropower performs more than two times worse than both large hydropower and wind power. Wind power compares similarly to large-scale hydropower regarding land occupation, much better on the reduction in INON areas, and in the same range regarding red-listed species. Our results demonstrate that the selected four parameters provide a basis for further development of a fair and consistent comparison of impacts between the analysed renewable technologies. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Integration of large amounts of wind power. Markets for trading imbalances

Energy Technology Data Exchange (ETDEWEB)

Neimane, Viktoria; Axelsson, Urban [Vattenfall Research and Development AB, Stockholm (Sweden); Gustafsson, Johan; Gustafsson, Kristian [Vattenfall Nordic Generation Management, Stockholm (Sweden); Murray, Robin [Vattenfall Vindkraft AB, Stockholm (Sweden)

2008-07-01

The well-known concerns about wind power are related to its intermittent nature and difficulty to make exact forecasts. The expected increase in balancing and reserve requirements due to wind power has been investigated in several studies. This paper takes the next step in studying integration of large amounts of wind power in Sweden. Several wind power producers' and corresponding balance providers' perspective is taken and their imbalance costs modeled. Larger producers having wind power spread over larger geographical areas will have lower relative costs than producers having their units concentrated within limited geographical area. Possibilities of the wind power producers to reduce the imbalance costs by acting on after sales market are exposed and compared. (orig.)

The role of research in the diffusion of wind technology

International Nuclear Information System (INIS)

Pirazzi, L.

2009-01-01

This last year for the first time in Europe the stunning global growth of wind technology has made wind energy to rank highest in diffusion among all energy sources. The role of research remains critical to achieve ever more ambitions E U goals. [it

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 total construction time is reduced to 7 years. Different financing options are regarded: a required internal rate of return of 10% or even 5% reduces the kWh cost price with 27% up to 50%. The effect of including the lifetimes of components in the price calculations is analysed, as well as the effect of considering the electrical grid as part of the public grid. With a maximum public effort the kWh cost price could be reduced to 8 ct. Integration of large-scale offshore wind energy in the distribution system can cause several technical and economic effects. These effects are caused by the variable wind supply, and can vary from insufficient grid connection capacity to the potential danger of a black out in the distribution system and large price fluctuations on the electricity market. To solve these problems, the application of backup power is introduced. Three types are regarded: an old coal plant, a new STEG plant, and hydroelectric power from Norway. Calculations show a moderate effect on the wind energy price due to backup power: this price increases with 6% up to 13%. In the backup power calculations an assumed market price is used, which makes it possible to predict a provisional value of an OWE green certificate. Finally, a comparison is made between the effect of possible technology improvements, public incentive effects and the effect of using backup power. This results in the conclusion that the feasibility of large-scale offshore wind energy depends more on public policy than on technology. 22 refs

Grid matching of large-scale wind energy conversion systems, alone and in tandem with large-scale photovoltaic systems: An Israeli case study

International Nuclear Information System (INIS)

Solomon, A.A.; Faiman, D.; Meron, G.

2010-01-01

This paper presents a grid matching analysis of wind energy conversion systems (WECSs) and photovoltaic (PV)-WECS hybrid systems. The study was carried out using hourly load data of the Israel Electric Corporation (IEC) for the year 2006 and the corresponding simulated hourly performance of large PV and WECS plants in the Negev Desert. Our major objective was to compare the grid-matching capabilities of wind with those of our previously published PV results, and to assess the extent to which the combined employment of WECS and PV can improve the grid matching capability of either technology when used on its own. We find that, due to the differences in diurnal and seasonal output profiles of WECS and PV, their tandem employment significantly improves grid penetration compared to their use individually.

Optimal Capacity Allocation of Large-Scale Wind-PV-Battery Units

Directory of Open Access Journals (Sweden)

Kehe Wu

2014-01-01

Full Text Available An optimal capacity allocation of large-scale wind-photovoltaic- (PV- battery units was proposed. First, an output power model was established according to meteorological conditions. Then, a wind-PV-battery unit was connected to the power grid as a power-generation unit with a rated capacity under a fixed coordinated operation strategy. Second, the utilization rate of renewable energy sources and maximum wind-PV complementation was considered and the objective function of full life cycle-net present cost (NPC was calculated through hybrid iteration/adaptive hybrid genetic algorithm (HIAGA. The optimal capacity ratio among wind generator, PV array, and battery device also was calculated simultaneously. A simulation was conducted based on the wind-PV-battery unit in Zhangbei, China. Results showed that a wind-PV-battery unit could effectively minimize the NPC of power-generation units under a stable grid-connected operation. Finally, the sensitivity analysis of the wind-PV-battery unit demonstrated that the optimization result was closely related to potential wind-solar resources and government support. Regions with rich wind resources and a reasonable government energy policy could improve the economic efficiency of their power-generation units.

IEA Wind TCP Task 26: Impacts of Wind Turbine Technology on the System Value of Wind in Europe

Energy Technology Data Exchange (ETDEWEB)

Lantz, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Riva, Alberto D [Ea Energy Analyses; Hethey, Janos [Ea Energy Analyses; Vitina, Aisma [Danish Energy Agency

2018-05-01

This report analyzes the impact of different land-based wind turbine designs on grid integration and related system value and cost. This topic has been studied in a number of previous publications, showing the potential benefits of wind turbine technologies that feature higher capacity factors. Building on the existing literature, this study aims to quantify the effects of different land-based wind turbine designs in the context of a projection of the European power system to 2030. This study contributes with insights on the quantitative effects in a likely European market setup, taking into account the effect of existing infrastructure on both existing conventional and renewable generation capacities. Furthermore, the market effects are put into perspective by comparing cost estimates for deploying different types of turbine design. Although the study focuses on Europe, similar considerations and results can be applied to other power systems with high wind penetration.

Intelligent control for large-scale variable speed variable pitch wind turbines

Institute of Scientific and Technical Information of China (English)

Xinfang ZHANG; Daping XU; Yibing LIU

2004-01-01

Large-scale wind turbine generator systems have strong nonlinear multivariable characteristics with many uncertain factors and disturbances.Automatic control is crucial for the efficiency and reliability of wind turbines.On the basis of simplified and proper model of variable speed variable pitch wind turbines,the effective wind speed is estimated using extended Kalman filter.Intelligent control schemes proposed in the paper include two loops which operate in synchronism with each other.At below-rated wind speed,the inner loop adopts adaptive fuzzy control based on variable universe for generator torque regulation to realize maximum wind energy capture.At above-rated wind speed, a controller based on least square support vector machine is proposed to adjust pitch angle and keep rated output power.The simulation shows the effectiveness of the intelligent control.

Two methods for estimating limits to large-scale wind power generation.

Science.gov (United States)

Miller, Lee M; Brunsell, Nathaniel A; Mechem, David B; Gans, Fabian; Monaghan, Andrew J; Vautard, Robert; Keith, David W; Kleidon, Axel

2015-09-08

Wind turbines remove kinetic energy from the atmospheric flow, which reduces wind speeds and limits generation rates of large wind farms. These interactions can be approximated using a vertical kinetic energy (VKE) flux method, which predicts that the maximum power generation potential is 26% of the instantaneous downward transport of kinetic energy using the preturbine climatology. We compare the energy flux method to the Weather Research and Forecasting (WRF) regional atmospheric model equipped with a wind turbine parameterization over a 10(5) km2 region in the central United States. The WRF simulations yield a maximum generation of 1.1 We⋅m(-2), whereas the VKE method predicts the time series while underestimating the maximum generation rate by about 50%. Because VKE derives the generation limit from the preturbine climatology, potential changes in the vertical kinetic energy flux from the free atmosphere are not considered. Such changes are important at night when WRF estimates are about twice the VKE value because wind turbines interact with the decoupled nocturnal low-level jet in this region. Daytime estimates agree better to 20% because the wind turbines induce comparatively small changes to the downward kinetic energy flux. This combination of downward transport limits and wind speed reductions explains why large-scale wind power generation in windy regions is limited to about 1 We⋅m(-2), with VKE capturing this combination in a comparatively simple way.

Assessment of research needs for wind turbine rotor materials technology

Energy Technology Data Exchange (ETDEWEB)

1991-01-01

Wind-driven power systems is a renewable energy technology that is still in the early stages of development. Wind power plants installed in early 1980s suffered structural failures chiefly because of incomplete understanding of wind forces (turbulent), in some cases because of poor product quality. Failures of rotor blades are now somewhat better understood. This committee has examined the experience base accumulated by wind turbines and the R and D programs sponsored by DOE. It is concluded that a wind energy system such as is described is within the capability of engineering practice; however because of certain gaps in knowledge, and the presence of only one major integrated manufacturer of wind power machines in the USA, a DOE R and D investment is still required.

2014-2015 Offshore Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Smith, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States); Stehly, Tyler [National Renewable Energy Lab. (NREL), Golden, CO (United States); Musial, Walter [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-09-01

This report provides data and analysis to assess the status of the U.S. offshore wind industry through June 30, 2015. It builds on the foundation laid by the Navigant Consortium, which produced three market reports between 2012 and 2014. The report summarizes domestic and global market developments, technology trends, and economic data to help U.S. offshore wind industry stakeholders, including policymakers, regulators, developers, financiers, and supply chain participants, to identify barriers and opportunities. Title page contains link to associated data tables posted at http://www.nrel.gov/docs/fy15osti/64283_data_tables.xlsx.

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)

Analysis of Ideal Towers for Tall Wind Applications

Energy Technology Data Exchange (ETDEWEB)

Dykes, Katherine L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Damiani, Rick R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Roberts, Joseph O [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lantz, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-01-12

Innovation in wind turbine tower design is of significant interest for future development of wind power plants. First, wind turbine towers account for a large portion of overall capital expenditures for wind power projects. Second, for low wind-resource regions of the world, the use of low-cost tall-tower technology has the potential to open new markets for development. This study investigates the relative potential of various tower configurations in terms of mass and cost. For different market applications and hub heights, idealized tall towers are designed and compared. The results show that innovation in wind turbine controls makes reaching higher hub heights with current technology economically viable. At the same time, new technologies hold promise for reducing tower costs as these technologies mature and hub heights reach twice the current average.

A fair wind blows for one green technology

International Nuclear Information System (INIS)

Marshall, E.

1993-01-01

The newest windmills are small and robust, typically capable of generating 50 to 500 kilowatts each. Sales have been helped along, both in Europe and the United States, by laws requiring utility companies to offer fixed purchase-price contracts to suppliers of wind electricity. Another boost comes from the National Energy Policy Act, signed into law last fall by George Bush. It permits a 1.5 cent per kilowatt-hour tax credit for generators of electricity from renewable sources. Emphasizing energy production is open-quotes a much smarter approachclose quotes than just rewarding construction of new windmills, says Alexander Ellis, an executive at Kenetech/US Windpower, because it encourages companies to deliver durable products. Today, the wind energy business seems to be booming, bearing out the Administration's faith that environmental technologies can open new markets. There are now more than 16,000 wind turbines installed in the United States, according to DeMeo, most of them still in California. Europe is also moving ahead. Although European countries have installed fewer machines to date, DeMeo says, the European Community has ambitious plans, calling for double the current US wind energy capacity by the end of the decade. About 10 major manufacturers in the United States and abroad are vying for this business. It took some fine-tuning, but government incentives to nurture this green technology seem to be working

Quiet airfoils for small and large wind turbines

Science.gov (United States)

Tangler, James L [Boulder, CO; Somers, Dan L [Port Matilda, PA

2012-06-12

Thick airfoil families with desirable aerodynamic performance with minimal airfoil induced noise. The airfoil families are suitable for a variety of wind turbine designs and are particularly well-suited for use with horizontal axis wind turbines (HAWTs) with constant or variable speed using pitch and/or stall control. In exemplary embodiments, a first family of three thick airfoils is provided for use with small wind turbines and second family of three thick airfoils is provided for use with very large machines, e.g., an airfoil defined for each of three blade radial stations or blade portions defined along the length of a blade. Each of the families is designed to provide a high maximum lift coefficient or high lift, to exhibit docile stalls, to be relatively insensitive to roughness, and to achieve a low profile drag.

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.

Mars Technologies Spawn Durable Wind Turbines

Science.gov (United States)

2014-01-01

To develop and test wind power technology for use on Mars, Ames Research Center turned to Northern Power Systems (NPS), based in Barre, Vermont. Ames awarded NPS an SBIR contract so the company could enhance their turbine’s function. Today, over 200 NASA-derived Northern Power 100s are in operation on Earth and have reduced carbon emissions by 50,000 tons annually.

Development of wind power generation in China

International Nuclear Information System (INIS)

Zhiquan, Y.; Yan, C.; Lijun, X.

1995-01-01

Present status and development of wind power generation in China is described in this paper. China is vast in territory with abundant wind resources. The exploitable wind energy in China is estimated up to 253,000 MW. At present, more than 150 thousand small WTGs of a total capacity of 17 MW are used to provide residential electricity uses in non-grid connected areas and 13 wind farms, with above 160 medium and large scale grid connected WTGs (50-500 kW) of a total capacity of 30 MW, have been constructed. At the same time, some progress has been made in the fields of nation-wide wind resource assessment, measurement technology of wind turbine performance, the assimilation of foreign wind turbine technology, grid connected WTG technology and the operation of wind farm etc. It is planned that the total installed capacity of WTGs will reach 1000 MW by the end of 2000. Wind power generation could be a part of electric power industry in China. (Author)

Size Reduction Techniques for Large Scale Permanent Magnet Generators in Wind Turbines

Science.gov (United States)

Khazdozian, Helena; Hadimani, Ravi; Jiles, David

2015-03-01

Increased wind penetration is necessary to reduce U.S. dependence on fossil fuels, combat climate change and increase national energy security. The U.S Department of Energy has recommended large scale and offshore wind turbines to achieve 20% wind electricity generation by 2030. Currently, geared doubly-fed induction generators (DFIGs) are typically employed in the drivetrain for conversion of mechanical to electrical energy. Yet, gearboxes account for the greatest downtime of wind turbines, decreasing reliability and contributing to loss of profit. Direct drive permanent magnet generators (PMGs) offer a reliable alternative to DFIGs by eliminating the gearbox. However, PMGs scale up in size and weight much more rapidly than DFIGs as rated power is increased, presenting significant challenges for large scale wind turbine application. Thus, size reduction techniques are needed for viability of PMGs in large scale wind turbines. Two size reduction techniques are presented. It is demonstrated that 25% size reduction of a 10MW PMG is possible with a high remanence theoretical permanent magnet. Additionally, the use of a Halbach cylinder in an outer rotor PMG is investigated to focus magnetic flux over the rotor surface in order to increase torque. This work was supported by the National Science Foundation under Grant No. 1069283 and a Barbara and James Palmer Endowment at Iowa State University.

Automatic Voltage Control System with Market Price Employing Large Wind Farms

DEFF Research Database (Denmark)

Qin, Nan; Bak, Claus Leth; Abildgaard, Hans

2018-01-01

of the voltage control service provided by the power plant owners. The benefit of employing the large offshore wind farms in this AVC system is investigated. The simulation based on the measurement data from the Danish electricity control center demonstrates the superiority of the proposed approach in terms...... of the cost minimization. The gained profit by employing the wind farms can be an argument to purchase the voltage control service provided by these wind farms....

The development of the Dutch wind energy technology in an international perspective

International Nuclear Information System (INIS)

Beurskens, H.J.M.

1990-01-01

An overview is given of the developments in the Dutch wind energy industry and the position of that industry in the industrialized world. First attention is paid to some historical developments of the modern wind energy technology in the Netherlands compared to some other countries. The start of the Integral Wind energy Program (IPW) at the end of 1985 brought the Dutch know-how of wind energy back on the international level. Next a brief overview is given of governmental wind energy programs which resulted in various projects aimed at designing, testing and implementing wind turbines in the Netherlands. Here too a comparison is made with other countries concerning the realized capacity, investments, and attempts to commercialize the wind turbines. The technological developments in the Netherlands can be characterized as gradual: step-by-step larger wind turbines (i.e. larger capacities) will be developed. The development of multi-megawatt turbines is too risky and too costly at present. Some final remarks state that the present position of the Dutch wind energy industry and the Dutch research activities are good starting-points to realize an important part of the wind energy capacity in Europe, or even the world. Recommendations are given by which the Dutch wind energy industry can operate with success on the international market. 5 figs., 3 tabs., 2 refs

Electric vehicles and large-scale integration of wind power

DEFF Research Database (Denmark)

Liu, Wen; Hu, Weihao; Lund, Henrik

2013-01-01

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...... 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...... 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...

Aeroelastic analysis of an offshore wind turbine: Design and Fatigue Performance of Large Utility-Scale Wind Turbine Blades

OpenAIRE

Fossum, Peter Kalsaas

2012-01-01

Aeroelastic design and fatigue analysis of large utility-scale wind turbine blades are performed. The applied fatigue model is based on established methods and is incorporated in an iterative numerical design tool for realistic wind turbine blades. All aerodynamic and structural design properties are available in literature. The software tool FAST is used for advanced aero-servo-elastic load calculations and stress-histories are calculated with elementary beam theory.According to wind energy ...

Wind Energy Technology: Training a Sustainable Workforce

Science.gov (United States)

Krull, Kimberly W.; Graham, Bruce; Underbakke, Richard

2009-01-01

Through innovative teaching and technology, industry and educational institution partnerships, Cloud County Community College is preparing a qualified workforce for the emerging wind industry estimated to create 80,000 jobs by 2020. The curriculum blends on-campus, on-line and distance learning, land-lab, and field training opportunities for…

In situ observations of the influence of a large onshore wind farm on near-surface temperature, turbulence intensity and wind speed profiles

Science.gov (United States)

Smith, Craig M.; Barthelmie, R. J.; Pryor, S. C.

2013-09-01

Observations of wakes from individual wind turbines and a multi-megawatt wind energy installation in the Midwestern US indicate that directly downstream of a turbine (at a distance of 190 m, or 2.4 rotor diameters (D)), there is a clear impact on wind speed and turbulence intensity (TI) throughout the rotor swept area. However, at a downwind distance of 2.1 km (26 D downstream of the closest wind turbine) the wake of the whole wind farm is not evident. There is no significant reduction of hub-height wind speed or increase in TI especially during daytime. Thus, in high turbulence regimes even very large wind installations may have only a modest impact on downstream flow fields. No impact is observable in daytime vertical potential temperature gradients at downwind distances of >2 km, but at night the presence of the wind farm does significantly decrease the vertical gradients of potential temperature (though the profile remains stably stratified), largely by increasing the temperature at 2 m.

In situ observations of the influence of a large onshore wind farm on near-surface temperature, turbulence intensity and wind speed profiles

International Nuclear Information System (INIS)

Smith, Craig M; Barthelmie, R J; Pryor, S C

2013-01-01

Observations of wakes from individual wind turbines and a multi-megawatt wind energy installation in the Midwestern US indicate that directly downstream of a turbine (at a distance of 190 m, or 2.4 rotor diameters (D)), there is a clear impact on wind speed and turbulence intensity (TI) throughout the rotor swept area. However, at a downwind distance of 2.1 km (26 D downstream of the closest wind turbine) the wake of the whole wind farm is not evident. There is no significant reduction of hub-height wind speed or increase in TI especially during daytime. Thus, in high turbulence regimes even very large wind installations may have only a modest impact on downstream flow fields. No impact is observable in daytime vertical potential temperature gradients at downwind distances of >2 km, but at night the presence of the wind farm does significantly decrease the vertical gradients of potential temperature (though the profile remains stably stratified), largely by increasing the temperature at 2 m. (letter)

Summary of tower designs for large horizontal axis wind turbines

Science.gov (United States)

Frederick, G. R.; Savino, J. M.

1986-01-01

Towers for large horizontal axis wind turbines, machines with a rotor axis height above 30 meters and rated at more than 500 kW, have varied in configuration, materials of construction, type of construction, height, and stiffness. For example, the U.S. large HAWTs have utilized steel truss type towers and free-standing steel cylindrical towers. In Europe, the trend has been to use only free-standing and guyed cylindrical towers, but both steel and reinforced concrete have been used as materials of construction. These variations in materials of construction and type of construction reflect different engineering approaches to the design of cost effective towers for large HAWTs. Tower designs are the NASA/DOE Mod-5B presently being fabricated. Design goals and requirements that influence tower configuration, height and materials are discussed. In particular, experiences with United States large wind turbine towers are elucidated. Finally, current trends in tower designs for large HAWTs are highlighted.

Impacts of large-scale offshore wind farm integration on power systems through VSC-HVDC

DEFF Research Database (Denmark)

Liu, Hongzhi; Chen, Zhe

2013-01-01

The potential of offshore wind energy has been commonly recognized and explored globally. Many countries have implemented and planned offshore wind farms to meet their increasing electricity demands and public environmental appeals, especially in Europe. With relatively less space limitation......, an offshore wind farm could have a capacity rating to hundreds of MWs or even GWs that is large enough to compete with conventional power plants. Thus the impacts of a large offshore wind farm on power system operation and security should be thoroughly studied and understood. This paper investigates...... the impacts of integrating a large-scale offshore wind farm into the transmission system of a power grid through VSC-HVDC connection. The concerns are focused on steady-state voltage stability, dynamic voltage stability and transient angle stability. Simulation results based on an exemplary power system...

Wind Turbine Technologies

DEFF Research Database (Denmark)

Hansen, Anca Daniela

2017-01-01

, and with or without gearboxes, using the latest in power electronics, aerodynamics, and mechanical drive train designs [4]. The main differences between all wind turbine concepts developed over the years, concern their electrical design and control. Today, the wind turbines on the market mix and match a variety......, the design of wind turbines has changed from being convention driven to being optimized driven within the operating regime and market environment. Wind turbine designs have progressed from fixed speed, passive controlled and with drive trains with gearboxes, to become variable speed, active controlled......,6] and to implement modern control system strategies....

Grid-friendly wind power systems based on the synchronverter technology

International Nuclear Information System (INIS)

Zhong, Qing-Chang; Ma, Zhenyu; Ming, Wen-Long; Konstantopoulos, George C.

2015-01-01

Highlights: • A grid-friendly wind power system that uses the synchronverter technology is proposed. • Both the rotor-side and the grid-side converters act as synchronverters. • The complete generator–motor–generator system improves the performance under grid faults. • Real-time digital simulation results verify the effectiveness of the proposed method. - Abstract: Back-to-back PWM converters are becoming a realistic alternative to conventional converters in high-power wind power applications. In this paper, a control strategy based on the synchronverter technology is proposed for back-to-back PWM converters. Both converters are run as synchronverters, which are mathematically equivalent to the conventional synchronous generators. The rotor-side converter is responsible for maintaining the DC link voltage and the grid-side converter is responsible for the maximum power point tracking (MPPT). As the two converters are operated using the synchronverter technology, the formed wind power system becomes more friendly to the grid. Extensive real-time digital simulation results are presented to verify the effectiveness of the proposed method under normal operation and grid-fault scenarios

The state of the art of wind energy conversion systems and technologies: A review

International Nuclear Information System (INIS)

Cheng, Ming; Zhu, Ying

2014-01-01

Highlights: • This paper reviews the state of the art of wind energy conversion systems. • Different types of common wind energy conversion systems are classified and compared. • The four most popular MPPT control methods are reviewed and compared. • The latest development of wind energy conversion technologies is introduced. • Future trends of the wind energy conversion technologies are discussed. - Abstract: This paper gives a comprehensive review of the state of the art of wind energy conversion systems (WECS) and technologies, with an emphasis on wind power generator and control. First, different types of common WECSs are classified according to their features and drive train types. The WECSs are compared on the basis of the volume, weight, cost, efficiency, system reliability and fault ride through capability. The maximum power point tracking (MPPT) control, which aims to make the generator speed meet an optimum value to ensure the maximum energy yield, plays a key role in the variable speed WECSs. A comprehensive review and comparison of the four most popular MPPT control methods are carried out and improvements for each method are presented. Furthermore, the latest development of wind energy conversion technologies is introduced, such as the brushless doubly fed induction generator (BDFIG), the stator permanent magnet synchronous generators, the magnetic-geared generators, dual power flow WECS with the electrical variable transmission (EVT) machine, and direct grid-connected WECS. Finally, the future trends of the technologies are discussed

Wind power integration into the automatic generation control of power systems with large-scale wind power

Directory of Open Access Journals (Sweden)

Abdul Basit

2014-10-01

Full Text Available Transmission system operators have an increased interest in the active participation of wind power plants (WPP in the power balance control of power systems with large wind power penetration. The emphasis in this study is on the integration of WPPs into the automatic generation control (AGC of the power system. The present paper proposes a coordinated control strategy for the AGC between combined heat and power plants (CHPs and WPPs to enhance the security and the reliability of a power system operation in the case of a large wind power penetration. The proposed strategy, described and exemplified for the future Danish power system, takes the hour-ahead regulating power plan for generation and power exchange with neighbouring power systems into account. The performance of the proposed strategy for coordinated secondary control is assessed and discussed by means of simulations for different possible future scenarios, when wind power production in the power system is high and conventional production from CHPs is at a minimum level. The investigation results of the proposed control strategy have shown that the WPPs can actively help the AGC, and reduce the real-time power imbalance in the power system, by down regulating their production when CHPs are unable to provide the required response.

Impacts of Large Scale Wind Penetration on Energy Supply Industry

Directory of Open Access Journals (Sweden)

John Kabouris

2009-11-01

Full Text Available Large penetration of Renewable Energy Sources (RES impacts Energy Supply Industry (ESI in many aspects leading to a fundamental change in electric power systems. It raises a number of technical challenges to the Transmission System Operators (TSOs, Distribution System Operators (DSOs and Wind Turbine Generators (WTG constructors. This paper aims to present in a thorough and coherent way the redrawn picture for Energy Systems under these conditions. Topics related to emergent technical challenges, technical solutions required and finally the impact on ESI due to large wind power penetration, are analyzed. Finally, general conclusions are extracted about the ESI current and future state and general directions are recommended.

Multidisciplinary design optimization of large wind turbines—Technical, economic, and design challenges

International Nuclear Information System (INIS)

Ashuri, Turaj; Zaaijer, Michiel B.; Martins, Joaquim R.R.A.; Zhang, Jie

2016-01-01

Highlights: • 5, 10 and 20 MW wind turbines are developed using multidisciplinary design optimization. • Technical feasibility and economy of large wind turbines are investigated. • Critical upscaling trends of existing wind turbines are presented up to 20 MW. • Design challenges of large wind turbines are identified, and design solutions proposed. • With no design innovation, upscaling of existing turbines will increase the costs. - Abstract: Wind energy has experienced a continuous cost reduction in the last decades. A popular cost reduction technique is to increase the rated power of the wind turbine by making it larger. However, it is not clear whether further upscaling of the existing wind turbines beyond the 5–7 MW range is technically feasible and economically attractive. To address this question, this study uses 5, 10, and 20 MW wind turbines that are developed using multidisciplinary design optimization as upscaling data points. These wind turbines are upwind, 3-bladed, pitch-regulated, variable-speed machines with a tubular tower. Based on the design data and properties of these wind turbines, scaling trends such as loading, mass, and cost are developed. These trends are used to study the technical and economical aspects of upscaling and its impact on the design and cost. The results of this research show the technical feasibility of the existing wind turbines up to 20 MW, but the design of such an upscaled machine is cost prohibitive. Mass increase of the rotor is identified as a main design challenge to overcome. The results of this research support the development of alternative lightweight materials and design concepts such as a two-bladed downwind design for upscaling to remain a cost effective solution for future wind turbines.

Analysis of Ideal Towers for Tall Wind Applications: Preprint

Energy Technology Data Exchange (ETDEWEB)

Dykes, Katherine L [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Damiani, Rick R [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Roberts, Joseph O [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lantz, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-02-27

Innovation in wind turbine tower design is of significant interest for future development of wind power plants. First, wind turbine towers account for a large portion of overall capital expenditures for wind power projects. Second, for low wind-resource regions of the world, the use of low-cost tall-tower technology has the potential to open new markets for development. This study investigates the relative potential of various tower configurations in terms of mass and cost. For different market applications and hub heights, idealized tall towers are designed and compared. The results show that innovation in wind turbine controls makes reaching higher hub heights with current technology economically viable. At the same time, new technologies hold promise for reducing tower costs as these technologies mature and hub heights reach twice the current average.

Development and Application of Advanced Weather Prediction Technologies for the Wind Energy Industry (Invited)

Science.gov (United States)

Mahoney, W. P.; Wiener, G.; Liu, Y.; Myers, W.; Johnson, D.

2010-12-01

Wind energy decision makers are required to make critical judgments on a daily basis with regard to energy generation, distribution, demand, storage, and integration. Accurate knowledge of the present and future state of the atmosphere is vital in making these decisions. As wind energy portfolios expand, this forecast problem is taking on new urgency because wind forecast inaccuracies frequently lead to substantial economic losses and constrain the national expansion of renewable energy. Improved weather prediction and precise spatial analysis of small-scale weather events are crucial for renewable energy management. In early 2009, the National Center for Atmospheric Research (NCAR) began a collaborative project with Xcel Energy Services, Inc. to perform research and develop technologies to improve Xcel Energy's ability to increase the amount of wind energy in their generation portfolio. The agreement and scope of work was designed to provide highly detailed, localized wind energy forecasts to enable Xcel Energy to more efficiently integrate electricity generated from wind into the power grid. The wind prediction technologies are designed to help Xcel Energy operators make critical decisions about powering down traditional coal and natural gas-powered plants when sufficient wind energy is predicted. The wind prediction technologies have been designed to cover Xcel Energy wind resources spanning a region from Wisconsin to New Mexico. The goal of the project is not only to improve Xcel Energy’s wind energy prediction capabilities, but also to make technological advancements in wind and wind energy prediction, expand our knowledge of boundary layer meteorology, and share the results across the renewable energy industry. To generate wind energy forecasts, NCAR is incorporating observations of current atmospheric conditions from a variety of sources including satellites, aircraft, weather radars, ground-based weather stations, wind profilers, and even wind sensors on

Bi-Level Decentralized Active Power Control for Large-Scale Wind Farm Cluster

DEFF Research Database (Denmark)

Huang, Shengli; Wu, Qiuwei; Guo, Yifei

2018-01-01

This paper presents a bi-level decentralized active power control (DAPC) for a large-scale wind farm cluster, consisting of several wind farms for better active power dispatch. In the upper level, a distributed active power control scheme based on the distributed consensus is designed to achieve...... fair active power sharing among multiple wind farms, which generates the power reference for each wind farm. A distributed estimator is used to estimate the total available power of all wind farms. In the lower level, a centralized control scheme based on the Model Predictive Control (MPC) is proposed...... to regulate active power outputs of all wind turbines (WTs) within a wind farm, which reduces the fatigue loads of WTs while tracking the power reference obtained from the upper level control. A wind farm cluster with 8 wind farms and totally 160 WTs, was used to test the control performance of the proposed...

Imbalance costs in the Swedish system with large amounts of wind power

Energy Technology Data Exchange (ETDEWEB)

Carlsson, Fredrik; Neimane, Viktoria [Vattenfall Research and Development AB, Stockholm (Sweden)

2009-07-01

The well-known concerns about wind power are related to its intermittent nature and difficulty to make exact forecasts. The expected increase in balancing and reserve requirements due to wind power has been investigated in several studies. This paper takes the next step in studying integration of large amounts of wind power in Sweden. Several wind power producers' and corresponding balance providers' perspective is taken and their imbalance costs modeled. Larger producers having wind power spread over larger geographical areas will have lower relative costs than producers having their units concentrated within limited geographical area. Possibilities of the wind power producers to reduce the imbalance costs by acting on after sales market are exposed and compared. (orig.)

Large-area photogrammetry based testing of wind turbine blades

Science.gov (United States)

Poozesh, Peyman; Baqersad, Javad; Niezrecki, Christopher; Avitabile, Peter; Harvey, Eric; Yarala, Rahul

2017-03-01

An optically based sensing system that can measure the displacement and strain over essentially the entire area of a utility-scale blade leads to a measurement system that can significantly reduce the time and cost associated with traditional instrumentation. This paper evaluates the performance of conventional three dimensional digital image correlation (3D DIC) and three dimensional point tracking (3DPT) approaches over the surface of wind turbine blades and proposes a multi-camera measurement system using dynamic spatial data stitching. The potential advantages for the proposed approach include: (1) full-field measurement distributed over a very large area, (2) the elimination of time-consuming wiring and expensive sensors, and (3) the need for large-channel data acquisition systems. There are several challenges associated with extending the capability of a standard 3D DIC system to measure entire surface of utility scale blades to extract distributed strain, deflection, and modal parameters. This paper only tries to address some of the difficulties including: (1) assessing the accuracy of the 3D DIC system to measure full-field distributed strain and displacement over the large area, (2) understanding the geometrical constraints associated with a wind turbine testing facility (e.g. lighting, working distance, and speckle pattern size), (3) evaluating the performance of the dynamic stitching method to combine two different fields of view by extracting modal parameters from aligned point clouds, and (4) determining the feasibility of employing an output-only system identification to estimate modal parameters of a utility scale wind turbine blade from optically measured data. Within the current work, the results of an optical measurement (one stereo-vision system) performed on a large area over a 50-m utility-scale blade subjected to quasi-static and cyclic loading are presented. The blade certification and testing is typically performed using International

A novel floating offshore wind turbine concept

DEFF Research Database (Denmark)

Vita, Luca; Schmidt Paulsen, Uwe; Friis Pedersen, Troels

2009-01-01

This paper will present a novel concept of a floating offshore wind turbine. The new concept is intended for vertical-axis wind turbine technology. The main purpose is to increase simplicity and to reduce total costs of an installed offshore wind farm. The concept is intended for deep water...... and large size turbines....

Basic controller tuning for large offshore wind turbines

Directory of Open Access Journals (Sweden)

K. O. Merz

2016-09-01

Full Text Available When a wind turbine operates above the rated wind speed, the blade pitch may be governed by a basic single-input–single-output PI controller, with the shaft speed as input. The performance of the wind turbine depends upon the tuning of the gains and filters of this controller. Rules of thumb, based upon pole placement, with a rigid model of the rotor, are inadequate for tuning the controller of large, flexible, offshore wind turbines. It is shown that the appropriate controller tuning is highly dependent upon the characteristics of the aeroelastic model: no single reference controller can be defined for use with all models. As an example, the ubiquitous National Renewable Energy Laboratory (NREL 5 MW wind turbine controller is unstable when paired with a fully flexible aeroelastic model. A methodical search is conducted, in order to find models with a minimum number of degrees of freedom, which can be used to tune the controller for a fully flexible aeroelastic model; this can be accomplished with a model containing 16–20 states. Transient aerodynamic effects, representing rotor-average properties, account for five of these states. A simple method is proposed to reduce the full transient aerodynamic model, and the associated turbulent wind spectra, to the rotor average. Ocean waves are also an important source of loading; it is recommended that the shaft speed signal be filtered such that wave-driven tower side-to-side vibrations do not appear in the PI controller output. An updated tuning for the NREL 5 MW controller is developed using a Pareto front technique. This fixes the instability and gives good performance with fully flexible aeroelastic models.

Electric Generators and their Control for Large Wind Turbines

DEFF Research Database (Denmark)

Boldea, Ion; Tutelea, Lucian; Rallabandi, Vandana

2017-01-01

induction generator, the cage rotor induction generator, and the synchronous generator with DC or permanent magnet excitation. The operating principle, performance, optimal design, and the modeling and control of the machine-side converter for each kind of generator are adressed and evaluated. In view......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...... of the fact that individual power rating of WTs has increased to around 10 MW, generator design and control technologies required to reach this power rating are discussed....

Locally manufactured wind power technology for sustainable rural electrification

International Nuclear Information System (INIS)

Leary, J.; While, A.; Howell, R.

2012-01-01

To date, the use of wind power for rural electrification has been limited. However the fact that micro-wind turbines can be manufactured using only basic workshop tools, techniques and materials, and therefore can be produced locally is often overlooked. Local manufacture has the potential to boost the local economy, build local capacity, reduce costs and produce resilient and flexible energy systems. However, locally manufactured technology must be seen as socially embedded due to the variety of local knowledge, skills, equipment and materials needed to construct and maintain such systems, as well as the organisational structures needed to ensure their long term sustainability. Evidence from successful initiatives suggests that stable institutional support from intermediaries such as the local/national government or NGOs is necessary to foster the development of a wind power industry based on local manufacture. The roles of these intermediaries include identifying and targeting windy areas with favourable environmental conditions, conducting research and development, collecting feedback from end users, creating supply chains for new parts and materials and developing relevant knowledge and skills. In this paper, three case studies of specific initiatives are analysed to draw out the social, economic and technical factors that could facilitate wider adoption of the technology. - Highlights: ► Local manufacture of wind turbines often overlooked for rural electrification. ► Flexible to adapt to local context and benefits local economy, capacity and supply chain. ► Development of technology discussed and 3 case studies of dissemination analysed. ► Critical factors: institutional support, system level planning, continuity of supply. ► Dissemination successful in Inner Mongolia; work continues elsewhere.

On the Fatigue Analysis of Wind Turbines

Energy Technology Data Exchange (ETDEWEB)

Sutherland, Herbert J.

1999-06-01

Modern wind turbines are fatigue critical machines that are typically used to produce electrical power from the wind. Operational experiences with these large rotating machines indicated that their components (primarily blades and blade joints) were failing at unexpectedly high rates, which led the wind turbine community to develop fatigue analysis capabilities for wind turbines. Our ability to analyze the fatigue behavior of wind turbine components has matured to the point that the prediction of service lifetime is becoming an essential part of the design process. In this review paper, I summarize the technology and describe the ''best practices'' for the fatigue analysis of a wind turbine component. The paper focuses on U.S. technology, but cites European references that provide important insights into the fatigue analysis of wind turbines.

Potential Offshore Wind Energy Areas in California: An Assessment of Locations, Technology, and Costs

Energy Technology Data Exchange (ETDEWEB)

Musial, Walter [National Renewable Energy Lab. (NREL), Golden, CO (United States); Beiter, Philipp [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tegen, Suzanne [National Renewable Energy Lab. (NREL), Golden, CO (United States); Smith, Aaron [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-12-01

This report summarizes a study of possible offshore wind energy locations, technologies, and levelized cost of energy in the state of California between 2015 and 2030. The study was funded by the U.S. Department of the Interior's Bureau of Ocean Energy Management (BOEM), the federal agency responsible for regulating renewable energy development on the Outer Continental Shelf. It is based on reference wind energy areas where representative technology and performance characteristics were evaluated. These reference areas were identified as sites that were suitable to represent offshore wind cost and technology based on physical site conditions, wind resource quality, known existing site use, and proximity to necessary infrastructure. The purpose of this study is to assist energy policy decision-making by state utilities, independent system operators, state government officials and policymakers, BOEM, and its key stakeholders. The report is not intended to serve as a prescreening exercise for possible future offshore wind development.

How to correct long-term system externality of large scale wind power development by a capacity mechanism?

International Nuclear Information System (INIS)

Cepeda, Mauricio; Finon, Dominique

2013-04-01

This paper deals with the practical problems related to long-term security of supply in electricity markets in the presence of large-scale wind power development. The success of renewable promotion schemes adds a new dimension to ensuring long-term security of supply. It necessitates designing second-best policies to prevent large-scale wind power development from distorting long-run equilibrium prices and investments in conventional generation and in particular in peaking units. We rely upon a long-term simulation model which simulates electricity market players' investment decisions in a market regime and incorporates large-scale wind power development either in the presence of either subsidised wind production or in market-driven development. We test the use of capacity mechanisms to compensate for the long-term effects of large-scale wind power development on the system reliability. The first finding is that capacity mechanisms can help to reduce the social cost of large scale wind power development in terms of decrease of loss of load probability. The second finding is that, in a market-based wind power deployment without subsidy, wind generators are penalized for insufficient contribution to the long term system's reliability. (authors)

IEA Wind Task 23 Offshore Wind Technology and Deployment. Subtask 1 Experience with Critical Deployment Issues. Final Technical Report

OpenAIRE

Lemming, Jørgen Kjærgaard

2010-01-01

The final report for IEA Wind Task 23, Offshore Wind Energy Technology and Deployment, is made up of two separate reports: Subtask 1: Experience with Critical Deployment Issues and Subtask 2: Offshore Code Comparison Collaborative (OC3). The Subtask 1 report included here provides background information and objectives of Task 23. It specifically discusses ecological issues and regulation, electrical system integration and offshore wind, external conditions, and key conclusions for Subtask 1. ...

Large-scale utilization of wind power in China: Obstacles of conflict between market and planning

International Nuclear Information System (INIS)

Zhao Xiaoli; Wang Feng; Wang Mei

2012-01-01

The traditional strict planning system that regulates China's power market dominates power industry operations. However, a series of market-oriented reforms since 1997 call for more decentralized decision-making by individual market participants. Moreover, with the rapid growth of wind power in China, the strict planning system has become one of the significant factors that has curtailed the generation of wind power, which contradicts with the original purpose of using the government's strong control abilities to promote wind power development. In this paper, we first present the reasons why market mechanisms are important for large-scale utilization of wind power by using a case analysis of the Northeast Grid, and then we illustrate the impact of conflicts between strict planning and market mechanisms on large-scale wind power utilization. Last, we explore how to promote coordination between markets and planning to realize large-scale wind power utilization in China. We argue that important measures include implementing flexible power pricing mechanisms instead of the current fixed pricing approach, formulating a more reasonable mechanism for distributing benefits and costs, and designing an appropriate market structure for large-scale wind power utilization to promote market liquidity and to send clear market equilibrium signals. - Highlights: ► We present the reasons why market is important for utilization of wind power. ► We discuss the current situation of the conflict between planning and market. ► We study the impact of conflict between planning and market on wind power output. ► We argue how to promote coordination between market and planning.

Establishment of a National Wind Energy Center at University of Houston

Energy Technology Data Exchange (ETDEWEB)

Wang, Su Su [Univ. of Houston, TX (United States)

2016-10-31

The DOE-supported project objectives are to: establish a national wind energy center (NWEC) at University of Houston and conduct research to address critical science and engineering issues for the development of future large MW-scale wind energy production systems, especially offshore wind turbines. The goals of the project are to: (1) establish a sound scientific/technical knowledge base of solutions to critical science and engineering issues for developing future MW-scale large wind energy production systems, (2) develop a state-of-the-art wind rotor blade research facility at the University of Houston, and (3) through multi-disciplinary research, introducing technology innovations on advanced wind-turbine materials, processing/manufacturing technology, design and simulation, testing and reliability assessment methods related to future wind turbine systems for cost-effective production of offshore wind energy. To achieve the goals of the project, the following technical tasks were planned and executed during the period from April 15, 2010 to October 31, 2014 at the University of Houston: (1) Basic research on large offshore wind turbine systems (2) Applied research on innovative wind turbine rotors for large offshore wind energy systems (3) Integration of offshore wind-turbine design, advanced materials and manufacturing technologies (4) Integrity and reliability of large offshore wind turbine blades and scaled model testing (5) Education and training of graduate and undergraduate students and post- doctoral researchers (6) Development of a national offshore wind turbine blade research facility The research program addresses both basic science and engineering of current and future large wind turbine systems, especially offshore wind turbines, for MW-scale power generation. The results of the research advance current understanding of many important scientific issues and provide technical information for solving future large wind turbines with advanced design

Low-frequency noise from large wind turbines.

Science.gov (United States)

Møller, Henrik; Pedersen, Christian Sejer

2011-06-01

As wind turbines get larger, worries have emerged that the turbine noise would move down in frequency and that the low-frequency noise would cause annoyance for the neighbors. The noise emission from 48 wind turbines with nominal electric power up to 3.6 MW is analyzed and discussed. The relative amount of low-frequency noise is higher for large turbines (2.3-3.6 MW) than for small turbines (≤ 2 MW), and the difference is statistically significant. The difference can also be expressed as a downward shift of the spectrum of approximately one-third of an octave. A further shift of similar size is suggested for future turbines in the 10-MW range. Due to the air absorption, the higher low-frequency content becomes even more pronounced, when sound pressure levels in relevant neighbor distances are considered. Even when A-weighted levels are considered, a substantial part of the noise is at low frequencies, and for several of the investigated large turbines, the one-third-octave band with the highest level is at or below 250 Hz. It is thus beyond any doubt that the low-frequency part of the spectrum plays an important role in the noise at the neighbors. © 2011 Acoustical Society of America

FY 1994 report on the results of the development of a large wind power system. Development of control technology of the array type wind power system; 1994 nendo ogata furyoku hatsuden system kaihatsu seika hokokusho. Shugogata furyoku hatsuden system no seigyo gijutsu no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

This technology development aims at developing the design technology of the array type wind power system and the control technology to efficiently operate the system. As a result, the wind turbine produced by Micon was selected. The rated power is 100kW, and the number of the wind turbine is three. The three-phase short-circuit capacity at the generating end of the wind power generation facilities is 26,25 MVA, which can fully be broken. A simulation of voltage variation/frequency variation was made to grasp various phenomena of the output of the wind power system influencing the power source system and power distribution system. As a result, it was confirmed that it is possible to operate the system safely without lowering the quality of power. As to the overall monitor/control system which controls wind turbines, five wind turbines as many as possible are grid-interconnected and the number of wind turbine is to be controlled by a ratio of the total demand power to the gross generating output of wind power in the Miyako system, for the purpose of increasing the rate of equipment utilization of the wind power system also at the time of the lowest load of the Miyako system. In the operation of two-system interconnection, the gross power generating amount was 1,321,250 kWh, which increased 9.7% over the results in FY 1993. (NEDO)

Factors influencing the technology upgrading and catch-up of Chinese wind turbine manufacturers: Technology acquisition mechanisms and government policies

International Nuclear Information System (INIS)

Qiu, Yueming; Ortolano, Leonard; David Wang, Yi

2013-01-01

This paper uses firm level data for the Chinese wind turbine manufacturing industry from 1998 to 2009 to quantify the effects of technology acquisition mechanisms – purchasing production licenses from foreign manufacturers, joint design with foreign design firms, joint-ventures and domestic R and D – on wind turbine manufacturers' technology levels (as measured by turbine size, in megawatts). It also examines the impacts of government policies on manufacturer technology levels. Technology upgrading (measured by increase of turbine size) and catch-up (measured by decrease in the distance to the world technology frontier in terms of turbine size) are used to measure advances in technology level. Results from econometric modeling studies indicate that firms' technology acquisition mechanisms and degree of business diversification are statistically significant factors in influencing technology upgrading. Similar results were found for the catch-up variable (i.e., distance to the world technology frontier). The influence of government policies is significant for technology upgrading but not catch-up. These and other modeling results are shown to have implications for both policymakers and wind turbine manufacturers. - Highlights: ► Technology acquired through joint design has the highest level. ► Technology acquired through purchasing production license has the lowest level. ► Technology acquired through domestic R and D has the level in between. ► A firm with related other businesses tends to have a higher level of technology. ► The influence of policies is significant for technology upgrade but not catch-up

Reliability, availability and maintenance aspects of large-scale offshore wind farms, a concepts study

NARCIS (Netherlands)

Van Bussel, G.J.W.; Zaayer, M.B.

2001-01-01

The DOWEC projects aims at implementation of large wind turbines in large scale wind farms. part of the DOWEC project a concepts study was performed regarding the achievable reliability and availability levels. A reduction with a factor of 2 with regard to the present state of the art seems fairly

Implementation of large-scale average geostrophic wind shear in WAsP12.1

DEFF Research Database (Denmark)

Floors, Rogier Ralph; Troen, Ib; Kelly, Mark C.

The vertical extrapolation model described in the European Wind Atlas Troen and Petersen (1989) is modified to take into account large-scale average geostrophic wind shear to describe the effect of horizontal temperature gradients on the geostrophic wind. The method is implemented by extracting...... the average geostrophic wind shear from Climate Forecast System Reanalysis (CFSR) data and the values of nearest grid point are automatically used in the WAsP 12.1 user interface to provide better AEP predictions....

Discontinuous Galerkin methodology for Large-Eddy Simulations of wind turbine airfoils

DEFF Research Database (Denmark)

Frére, A.; Sørensen, Niels N.; Hillewaert, K.

2016-01-01

This paper aims at evaluating the potential of the Discontinuous Galerkin (DG) methodology for Large-Eddy Simulation (LES) of wind turbine airfoils. The DG method has shown high accuracy, excellent scalability and capacity to handle unstructured meshes. It is however not used in the wind energy...... sector yet. The present study aims at evaluating this methodology on an application which is relevant for that sector and focuses on blade section aerodynamics characterization. To be pertinent for large wind turbines, the simulations would need to be at low Mach numbers (M ≤ 0.3) where compressible...... at low and high Reynolds numbers and compares the results to state-of-the-art models used in industry, namely the panel method (XFOIL with boundary layer modeling) and Reynolds Averaged Navier-Stokes (RANS). At low Reynolds number (Re = 6 × 104), involving laminar boundary layer separation and transition...

IEA Wind Task 23 Offshore Wind Technology and Deployment. Subtask 1 Experience with Critical Deployment Issues. Final Technical Report

DEFF Research Database (Denmark)

Lemming, Jørgen Kjærgaard

The final report for IEA Wind Task 23, Offshore Wind Energy Technology and Deployment, is made up of two separate reports: Subtask 1: Experience with Critical Deployment Issues and Subtask 2: Offshore Code Comparison Collaborative (OC3). The Subtask 1 report included here provides background...... information and objectives of Task 23. It specifically discusses ecological issues and regulation, electrical system integration and offshore wind, external conditions, and key conclusions for Subtask 1. The Subtask 2 report covers OC3 background information and objectives of the task, OC3 benchmark exercises...... of aero-elastic offshore wind turbine codes, monopile foundation modeling, tripod support structure modeling, and Phase IV results regarding floating wind turbine modeling....

Wind energy in Europe

International Nuclear Information System (INIS)

Evans, L.C.

1992-01-01

Wind energy should be an important part of the energy supply mix, both at home and abroad, to provide cleaner air and a more stable fuel supply. Not only can wind energy contribute to solving complex global issues, it also can provide a large market for American technological leadership. Even though utilities are paying more attention to wind in a number of states, there are no plans for major installations of wind power plants in the United States. At the same time, European nations have developed aggressive wind energy development programs, including both ambitious research and development efforts and market incentives. Many countries recognize the importance of the clean energy provided by wind technology and are taking steps to promote their fledgling domestic industries. The emphasis on market incentives is starting to pay off. In 1991, European utilities and developers installed nearly twice as much wind capacity as Americans did. In 1992 the gap will be even greater. This article reviews aggressive incentives offered by European governments to boost their domestic wind industries at home and abroad in this almost $1 billion per year market. By offering substantial incentives - considerably more than the American Wind Energy Association (AWEA) is proposing - European nations are ensuring dramatic near-term wind energy development and are taking a major step toward dominating the international wind industry of the 21st century

Comparison of Large Eddy Simulations of a convective boundary layer with wind LIDAR measurements

DEFF Research Database (Denmark)

Pedersen, Jesper Grønnegaard; Kelly, Mark C.; Gryning, Sven-Erik

2012-01-01

Vertical profiles of the horizontal wind speed and of the standard deviation of vertical wind speed from Large Eddy Simulations of a convective atmospheric boundary layer are compared to wind LIDAR measurements up to 1400 m. Fair agreement regarding both types of profiles is observed only when...

Wind energy - an overview

International Nuclear Information System (INIS)

Rangi, R.; Oprisan, M.

1998-01-01

The current status of wind technology developments in Canada and around the world was reviewed. Information regarding the level of wind turbine deployment was presented. It was shown that significant effort has been made on the national and international level to increase the capacity of this clean, non-polluting form of energy. Wind energy has become competitive with conventional sources of electricity due to lower cost, higher efficiency and improved reliability of generating equipment. The advantages and disadvantages of wind electricity generating systems and the economics and atmospheric emissions of the systems were described. At present, there is about 23 MW of wind energy generating capacity installed in Canada, but the potential is very large. It was suggested that wind energy could supply as much as 60 per cent of Canada's electricity needs if only one per cent of the land with 'good winds' were covered by wind turbines. Recently, the Canadian government has provided an accelerated capital cost allowance for certain types of renewable energies under the Income Tax Act, and the flow-through share financing legislation to include intangible expenses in certain renewable energy projects has been extended. Besides the support provided to the private sector through tax advantages, the Government also supports renewable energy development by purchasing 'green' energy for its own buildings across the country, and by funding a research and development program to identify and promote application of wind energy technologies, improve its cost effectiveness, and support Canadian wind energy industries with technology development to enhance their competitiveness at home and abroad. Details of the Wind Energy Program, operated by Natural Resources Canada, are described. 3 tabs., 5 figs

How to correct for long-term externalities of large-scale wind power development by a capacity mechanism?

International Nuclear Information System (INIS)

Cepeda, Mauricio; Finon, Dominique

2013-01-01

This paper deals with the practical problems related to long-term security of supply in electricity markets in the presence of large-scale wind power development. The success of recent renewable promotion schemes adds a new dimension to ensuring long-term security of supply: it necessitates designing second-best policies to prevent large-scale wind power development from distorting long-run equilibrium prices and investments in conventional generation and in particular in peaking units. We rely upon a long-term simulation model which simulates electricity market players' investment decisions in a market regime and incorporates large-scale wind power development in the presence of either subsidized or market driven development scenarios. We test the use of capacity mechanisms to compensate for long-term effects of large-scale wind power development on prices and reliability of supply. The first finding is that capacity mechanisms can help to reduce the social cost of large scale wind power development in terms of decrease of loss of load probability. The second finding is that, in a market-based wind power deployment without subsidy, wind generators are penalised for insufficient contribution to the long term system's reliability. - Highlights: • We model power market players’ investment decisions incorporating wind power. • We examine two market designs: an energy-only market and a capacity mechanism. • We test two types of wind power development paths: subsidised and market-driven. • Capacity mechanisms compensate for the externalities of wind power developments

TradeWind. Integrating wind. Developing Europe's power market for the large-scale integration of wind power. Final report

Energy Technology Data Exchange (ETDEWEB)

2009-02-15

Based on a single European grid and power market system, the TradeWind project explores to what extent large-scale wind power integration challenges could be addressed by reinforcing interconnections between Member States in Europe. Additionally, the project looks at the conditions required for a sound power market design that ensures a cost-effective integration of wind power at EU level. In this way, the study addresses two issues of key importance for the future integration of renewable energy, namely the weak interconnectivity levels between control zones and the inflexibility and fragmented nature of the European power market. Work on critical transmission paths and interconnectors is slow for a variety of reasons including planning and administrative barriers, lack of public acceptance, insufficient economic incentives for TSOs, and the lack of a joint European approach by the key stakeholders. (au)

Environmental aspects of large-scale wind-power systems in the UK

Science.gov (United States)

Robson, A.

1984-11-01

Environmental issues relating to the introduction of large, MW-scale wind turbines at land-based sites in the UK are discussed. Noise, television interference, hazards to bird life, and visual effects are considered. Areas of uncertainty are identified, but enough is known from experience elsewhere in the world to enable the first UK machines to be introduced in a safe and environementally acceptable manner. Research to establish siting criteria more clearly, and significantly increase the potential wind-energy resource is mentioned. Studies of the comparative risk of energy systems are shown to be overpessimistic for UK wind turbines.

Safety considerations in the design and operation of large wind turbines

Science.gov (United States)

Reilly, D. H.

1979-01-01

The engineering and safety techniques used to assure the reliable and safe operation of large wind turbine generators utilizing the Mod 2 Wind Turbine System Program as an example is described. The techniques involve a careful definition of the wind turbine's natural and operating environments, use of proven structural design criteria and analysis techniques, an evaluation of potential failure modes and hazards, and use of a fail safe and redundant component engineering philosophy. The role of an effective quality assurance program, tailored to specific hardware criticality, and the checkout and validation program developed to assure system integrity are described.

From lagging to leading? Technological innovation systems in emerging economies and the case of Chinese wind power

International Nuclear Information System (INIS)

Gosens, Jorrit; Lu, Yonglong

2013-01-01

There is increasing attention for the contribution of emerging economies to global innovation, including innovation of renewable energy technologies. The Technological Innovation Systems (TIS) framework presents a list of system functions for the analysis of the development of a technology. It has often been applied to renewable energy technologies, but with a strong focus on advanced economies. In this paper, we elaborate on emerging economy innovation system formation, structured according to TIS functions. Rather than analysing development of the technology, we analyse the development of the Chinese TIS vis-à-vis the global forefront. Key to this notion is that TIS, especially for clean-tech, are transnational phenomena. Lagging TIS depend on the global TIS, whereas leading TIS contribute to its formation. It is concluded that China has reduced its dependence on foreign knowledge and investment, but the outward contribution remains limited. The main challenge to foreign market expansion lies in reforming the domestic TIS to focus on turbine quality rather than cost reduction. Demonstration projects are needed, especially for large capacity and offshore turbine models, in order to build up operational history and get quality certification. - Highlights: • The TIS framework was adapted to suit emerging economy case studies. • China's wind power TIS is emerging vis-à-vis the global forefront. • China's wind power TIS has reduced its dependence on foreign knowledge and finance. • Chinese innovative activity for wind power remains limited to the domestic context. • Foreign market expansion requires a focus on turbine quality and certification

Large Wind Turbine Design Characteristics and R and D Requirements

Science.gov (United States)

Lieblein, S. (Editor)

1979-01-01

Detailed technical presentations on large wind turbine research and development activities sponsored by public and private organizations are presented. Both horizontal and vertical axis machines are considered with emphasis on their structural design.

Financing wind projects

International Nuclear Information System (INIS)

Manson, J.

2006-01-01

This presentation reviewed some of the partnership opportunities available from GE Energy. GE Energy's ecomagination commitment has promised to double research investment, make customers true partners and reduce greenhouse gases (GHGs). GE Energy's renewable energy team provides a broad range of financial products, and has recently funded 30 wind farms and 2 large solar projects. The company has a diverse portfolio of technology providers and wind regimes, and is increasing their investment in technology. GE Energy recognizes that the wind industry is growing rapidly and has received increased regulatory support that is backed by strong policy and public support. It is expected that Canada will have 3006 wind projects either planned or under construction by 2007. According to GE Energy, successful wind financing is dependent on the location of the site and its wind resources, as well as on the wind developer's power sales agreement. The success of a wind project is also determined by clear financing goals. Site-specific data is needed to determine the quality of wind resource, and off-site data can also be used to provide validation. Proximity to load centres will help to minimize capital costs. Power sales agreements should be based on the project's realistic net capacity factor as well as on the cost of the turbines. The economics of many wind farms is driven by the size of the turbines used. Public consultations are also needed to ensure the success of wind power projects. It was concluded that a good partner will have staying power in the wind power industry, and will understand the time-lines and needs that are peculiar to wind energy developers. refs., tabs., figs

Low-frequency noise from large wind turbines

DEFF Research Database (Denmark)

Møller, Henrik; Pedersen, Christian Sejer

2011-01-01

As wind turbines get larger, worries have emerged that the turbine noise would move down in frequency and that the low-frequency noise would cause annoyance for the neighbors. The noise emission from 48 wind turbines with nominal electric power up to 3.6 MW is analyzed and discussed. The relative...... amount of low-frequency noise is higher for large turbines (2.3–3.6 MW) than for small turbines (≤ 2 MW), and the difference is statistically significant. The difference can also be expressed as a downward shift of the spectrum of approximately one-third of an octave. A further shift of similar size...... is suggested for future turbines in the 10-MW range. Due to the air absorption, the higher low-frequency content becomes even more pronounced, when sound pressure levels in relevant neighbor distances are considered. Even when A-weighted levels are considered, a substantial part of the noise is at low...

8th international workshop on large-scale integration of wind power into power systems as well as on transmission networks for offshore wind farms. Proceedings

International Nuclear Information System (INIS)

Betancourt, Uta; Ackermann, Thomas

2009-01-01

Within the 8th International Workshop on Large-Scale Integration of Wind Power into Power Systems as well as on Transmission Networks for Offshore Wind Farms at 14th to 15th October, 2009 in Bremen (Federal Republic of Germany), lectures and posters were presented to the following sessions: (1) Keynote session and panel; (2) Grid integration studies and experience: Europe; (3) Connection of offshore wind farms; (4) Wind forecast; (5) High voltage direct current (HVDC); (6) German grid code issues; (7) Offshore grid connection; (8) Grid integration studies and experience: North America; (9) SUPWIND - Decision support tools for large scale integration of wind; (10) Windgrid - Wind on the grid: An integrated approach; (11) IEA Task 25; (12) Grid code issues; (13) Market Issues; (14) Offshore Grid; (15) Modelling; (16) Wind power and storage; (17) Power system balancing; (18) Wind turbine performance; (19) Modelling and offshore transformer.

Canadian Wind Energy Association small wind conference proceedings : small wind policy developments (turbines of 300 kW or less)

International Nuclear Information System (INIS)

2005-01-01

The small wind session at the Canadian Wind Energy Association's (CanWEA) annual conference addressed policies affecting small wind, such as net metering, advanced renewable tariffs and interconnections. It also addressed CanWEA's efforts in promoting small wind turbines, particularly in remote northern communities, small businesses and within the residential sector. Small wind systems are typically installed in remote communities to offset utility supplied electricity at the retail price level. In certain circumstances, small wind and hybrid systems can produce electricity at less than half the cost of traditional electricity sources, which in remote communities is typically diesel generators. Small wind turbines require different materials and technologies than large wind turbines. They also involve different local installation requirements, different by-laws, tax treatment and environmental assessments. Small wind turbines are typically installed for a range of factors, including energy independence, energy price stability and to lower environmental impacts of traditional power generation. The small wind session at the conference featured 14 presentations, of which 4 have been catalogued separately for inclusion in this database. tabs., figs

Technological and economic preconditions for the construction of wind power stations on inland sites

International Nuclear Information System (INIS)

Stapperfenne, W.

1992-01-01

In principle, wind power is perceived as a manageable and soft-type energy; nevertheless operators are advised against trying to design and build wind power plants based on their very own ideas since these will often be found to fall short of the stringent requirements of regulatory authorities for safety, wind technology and statics, and of the demand of knowledge in mechanical engineering, electronics and computer technology. In addition, the utilization of wind power is ruled by tax laws since a certain are of the power produced will have to be fed to the national grid which means that the plant operator is a producer subjected to value-added taxation with the right of reimbussement of prepaid taxes [de

Wind Power Today: Wind Energy Program Highlights 2001

Energy Technology Data Exchange (ETDEWEB)

2002-05-01

Wind Power Today is an annual publication that provides an overview of the U.S. Department of Energy's Wind Energy Program accomplishments for the previous year. The purpose of Wind Power Today is to show how DOE's Wind Energy Program supports wind turbine research and deployment in hopes of furthering the advancement of wind technologies that produce clean, low-cost, reliable energy. Content objectives include: educate readers about the advantages and potential for widespread deployment of wind energy; explain the program's objectives and goals; describe the program's accomplishments in research and application; examine the barriers to widespread deployment; describe the benefits of continued research and development; facilitate technology transfer; and attract cooperative wind energy projects with industry. This 2001 edition of Wind Power Today also includes discussions about wind industry growth in 2001, how DOE is taking advantage of low wind speed regions through advancing technology, and distributed applications for small wind turbines.

Technology mix alternatives with high shares of wind power and photovoltaics—case study for Spain

International Nuclear Information System (INIS)

Zubi, Ghassan

2011-01-01

The shift to a low carbon society is an issue of highest priority in the EU. For electricity generation, such a target counts with three main alternatives: renewable energies, nuclear power and carbon capture and storage. This paper focuses on the renewables’ alternative. Due to resource availability, a technology mix with a high share of PV and wind power is gaining increasing interest as a major solution for several EU member states and in part for the EU collectively to achieve decarbonization and energy security with acceptable costs. Due to their intermittency, the integration of high shares of PV and wind power in the electricity supply is challenging. This paper presents a techno-economic assessment of technology mix alternatives with a high share of PV and wind power in Spain, as an example. Thereby, the focus is on the option of increasing wind curtailment versus substituting rigid baseload generation in favor of the more flexible gas turbines and combined cycle gas turbines. - Highlights: ► The potential of power generation from renewable energy resources in the EU is illustrated. ► The LEC of the different technologies considered is calculated for today and future scenarios. ► An excel-based model for the technology mix assessment is applied using Spanish data. ► Technology mix alternatives with a high share of PV and wind power are assessed. ► The focus is on increasing wind curtailment vs. relying on more flexible power generation units.

The axial flux generator of the Octopus Wind Technology. A feasibility study; De axiale flux-generator van Octopus Wind Technology. Een haalbaarheidsstudie

Energy Technology Data Exchange (ETDEWEB)

Van Schie, R. [ECN Technologische Services and Consultancy, Petten (Netherlands)

2001-02-01

This report presents the results of a feasibility study of a generator concept for wind turbines that was suggested by Octopus Wind Technology (OWT). In this concept the following ideas were implemented: (1) The generator is a direct-drive generator with permanent magnets; (2) (Sliding) bearings are integrated in the generator on the circumference; (3) Rotor and stator are divided into (radial) modular segments; (4) The generator has an axial magnetic flux; (5) The blades of the turbine are mounted between the rotors. The result of this study is that the OWT-concept has to be changed. It is better to mount the turbine blades on a compact hub than on the large rotor ring. Also in this concept there is no reason to choose for the axial magnetic flux. The use of modules, of permanent magnets and a large bearing are very useful developments in wind turbines and are already examined or implemented. The application of a bearing on an even larger diameter of approximately 3,5 m still is (very) expensive. Hydrostatic bearings are the sliding bearings to implement on this diameter and have the advantage of being modular as well. The drawback of this bearing type is the use of oil. Jeumont uses axial modules in their generator design. The objective is to use the same modules in turbines with different power ratings. In the OWT-concept the modules are radial and the aim is ease of production, transport and maintenance. This idea was already patented in December 1998 (US-patent 5 844 341) for a radial flux machine and that appeared to be the logical choice. It is concluded that after the desired changes the OWT-concept has insufficient unique characteristics to protect the design. Most of the good ideas in the OWT-concept were already implemented in the research work following the mentioned patent and in the design of the LW 50/750. A combination of these ideas could be a good basis for a new turbine design, but a detailed analysis is needed to examine the true perspective of

Credit Trading and Wind Power: Issues and Opportunities

Energy Technology Data Exchange (ETDEWEB)

Kevin Rackstraw, John Palmisano

2001-01-15

OAK-B135 This paper focuses on credits that are derived from wind energy technology, but the same concepts apply to other renewable energy technologies as well. Credit trading can be applied to a wide variety of policies, programs and private market activities and represents a means of tapping into revenue streams that heretofore have largely excluded wind and other renewables. In addition, credit trading can help to ''create'' new revenue streams for wind and other renewables by helping to grow new markets.

Small scale wind power harnessing in Colombian oil industry facilities: Wind resource and technology issues

Energy Technology Data Exchange (ETDEWEB)

Giraldo, Mauricio; Nieto, Cesar; Escudero, Ana C.; Cobos, Juan C.; Delgado, Fernando

2010-07-01

Full text: Looking to improve its national and international standing, Colombia's national oil company, Ecopetrol, has set its goal on becoming involved on the production of energy from multiple sources, most importantly, on having an important percentage of its installed capacity from renewable sources. Part of this effort entices the evaluation of wind power potential on its facilities, including production, transportation and administrative, as well as identifying those technologies most suitable for the specific conditions of an equatorial country such as Colombia. Due to the lack of adequate site information, the first step consisted in superimposing national data to the facilities map of the company; this allowed for the selection of the first set of potential sites. From this set, the terminal at Covenas-Sucre was selected taking into account not only wind resource, but ease of access and power needs, as well as having a more or less representative wind potential in comparison to the rest of the country. A weather station was then installed to monitor wind variables. Measurements taken showed high variations in wind direction, and relatively low velocity profiles, making most commercially available wind turbines difficult to implement. In light of the above, a series of iterative steps were taken, first considering a range of individual Vertical Axis Wind Turbines (VAWT), given their capacity to adapt to changing wind directions. However, wind speed variations proved to be a challenge for individual VAWT's, i.e. Darriues turbines do not work well with low wind speeds, and Savonius turbines are not efficient of high wind speeds. As a result, a combined Darrieus- Savonius VAWT was selected given the capacity to adapt to both wind regimes, while at the same time modifying the size and shape of the blades in order to adapt to the lower average wind speeds present at the site. The resulting prototype is currently under construction and is scheduled to

Environmental aspects of large-scale wind-power systems in the UK

Energy Technology Data Exchange (ETDEWEB)

Robson, A

1983-12-01

Environmental issues relating to the introduction of large, MW-scale wind turbines at land-based sites in the U.K. are discussed. Areas of interest include noise, television interference, hazards to bird life and visual effects. A number of areas of uncertainty are identified, but enough is known from experience elsewhere in the world to enable the first U.K. machines to be introduced in a safe and environmentally acceptable manner. Research currently under way will serve to establish siting criteria more clearly, and could significantly increase the potential wind-energy resource. Certain studies of the comparative risk of energy systems are shown to be overpessimistic for U.K. wind turbines.

Dynamic Loads and Wake Prediction for Large Wind Turbines Based on Free Wake Method

Institute of Scientific and Technical Information of China (English)

Cao Jiufa; Wang Tongguang; Long Hui; Ke Shitang; Xu Bofeng

2015-01-01

With large scale wind turbines ,the issue of aerodynamic elastic response is even more significant on dy-namic behaviour of the system .Unsteady free vortex wake method is proposed to calculate the shape of wake and aerodynamic load .Considering the effect of aerodynamic load ,inertial load and gravity load ,the decoupling dy-namic equations are established by using finite element method in conjunction of the modal method and equations are solved numerically by Newmark approach .Finally ,the numerical simulation of a large scale wind turbine is performed through coupling the free vortex wake modelling with structural modelling .The results show that this coupling model can predict the flexible wind turbine dynamic characteristics effectively and efficiently .Under the influence of the gravitational force ,the dynamic response of flapwise direction contributes to the dynamic behavior of edgewise direction under the operational condition of steady wind speed .The difference in dynamic response be-tween the flexible and rigid wind turbines manifests when the aerodynamics/structure coupling effect is of signifi-cance in both wind turbine design and performance calculation .

A Comparison Study between Two MPPT Control Methods for a Large Variable-Speed Wind Turbine under Different Wind Speed Characteristics

Directory of Open Access Journals (Sweden)

Dongran Song

2017-05-01

Full Text Available Variable speed wind turbines (VSWTs usually adopt a maximum power point tracking (MPPT method to optimize energy capture performance. Nevertheless, obtained performance offered by different MPPT methods may be affected by the impact of wind turbine (WT’s inertia and wind speed characteristics and it needs to be clarified. In this paper, the tip speed ratio (TSR and optimal torque (OT methods are investigated in terms of their performance under different wind speed characteristics on a 1.5 MW wind turbine model. To this end, the TSR control method based on an effective wind speed estimator and the OT control method are firstly presented. Then, their performance is investigated and compared through simulation test results under different wind speeds using Bladed software. Comparison results show that the TSR control method can capture slightly more wind energy at the cost of high component loads than the other one under all wind conditions. Furthermore, it is found that both control methods present similar trends of power reduction that is relevant to mean wind speed and turbulence intensity. From the obtained results, we demonstrate that, to further improve MPPT capability of large VSWTs, other advanced control methods using wind speed prediction information need to be addressed.

Dynamic model of frequency control in Danish power system with large scale integration of wind power

DEFF Research Database (Denmark)

Basit, Abdul; Hansen, Anca Daniela; Sørensen, Poul Ejnar

2013-01-01

This work evaluates the impact of large scale integration of wind power in future power systems when 50% of load demand can be met from wind power. The focus is on active power balance control, where the main source of power imbalance is an inaccurate wind speed forecast. In this study, a Danish...... power system model with large scale of wind power is developed and a case study for an inaccurate wind power forecast is investigated. The goal of this work is to develop an adequate power system model that depicts relevant dynamic features of the power plants and compensates for load generation...... imbalances, caused by inaccurate wind speed forecast, by an appropriate control of the active power production from power plants....

Distributed Wind Market Applications

Energy Technology Data Exchange (ETDEWEB)

Forsyth, T.; Baring-Gould, I.

2007-11-01

Distributed wind energy systems provide clean, renewable power for on-site use and help relieve pressure on the power grid while providing jobs and contributing to energy security for homes, farms, schools, factories, private and public facilities, distribution utilities, and remote locations. America pioneered small wind technology in the 1920s, and it is the only renewable energy industry segment that the United States still dominates in technology, manufacturing, and world market share. The series of analyses covered by this report were conducted to assess some of the most likely ways that advanced wind turbines could be utilized apart from large, central station power systems. Each chapter represents a final report on specific market segments written by leading experts in this field. As such, this document does not speak with one voice but rather a compendium of different perspectives, which are documented from a variety of people in the U.S. distributed wind field.

Basics on wind energy; Introduction a l'energie eolienne

Energy Technology Data Exchange (ETDEWEB)

Paluch, B. [ONERA, Dept. Mecanique des Structures et de L' endommagement (DMSE), 59 - Lille (France)

2005-05-01

Among all the renewable energies, wind energy knows the strongest progression. The EEC, and more particularly Germany, are at the world top position. Many countries now consider offshore as an alternative to land sites saturation. The three-bladed horizontal axis wind turbines largely dominate the market. The tendency lies now in the multi-megawatts wind turbines exceeding 80 m in diameter. Wind energy takes benefits from mature technologies, since there are less and less expensive and easily exploitable. However many technological challenges still remain to raise. In some countries, the obligation to buy the electricity produced by wind energy at attractive rates allowed the growth of a wind industrial sector, exporting technologies and generating employment. Within the framework of sustainable development, the resource durability has direct repercussions on the local economies. (author)

Modelization of a large wind farm, considering the modification of the atmospheric boundary layer

Energy Technology Data Exchange (ETDEWEB)

Crespo, A; Gomez-Elvira, R [Univ. Politecnica de Madrid, Mecanica de Fluidos, E.T.S.I. Industriales, Madrid (Spain); Frandsen, S; Larsen, S E [Risoe National Lab., Roskilde (Denmark)

1999-03-01

A method is presented to adapt existing models of wind farms to very large ones that may affect the whole planetary boundary layer. An internal boundary layer is considered that starts developing at the leading edge of the farm until it reaches, sufficiently far downstream, the top of the planetary boundary layer, and a new equilibrium region is reached. The wind farm is simulated by an artificial roughness that is function of the turbine spacing, drag and height. From this model the flow conditions are calculated at a certain reference height and then are used as boundary conditions for a numerical code used to model a wind farm. Three-dimensional effects are considered by applying appropriate conditions at the sides of the farm. Calculations are carried out to estimate the energy production in large wind farms, and it is found that additional losses due to modification of the planetary boundary layer may be of importance for wind farms of size larger than about 100 km. (au)

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

Wind Generators

Science.gov (United States)

1989-01-01

When Enerpro, Inc. president, Frank J. Bourbeau, attempted to file a patent on a system for synchronizing a wind generator to the electric utility grid, he discovered Marshall Space Flight Center's Frank Nola's power factor controller. Bourbeau advanced the technology and received a NASA license and a patent for his Auto Synchronous Controller (ASC). The ASC reduces generator "inrush current," which occurs when large generators are abruptly brought on line. It controls voltage so the generator is smoothly connected to the utility grid when it reaches its synchronous speed, protecting the components from inrush current damage. Generator efficiency is also increased in light winds by applying lower than rated voltage. Wind energy is utilized to drive turbines to generate electricity for utility companies.

Cost-efficient foundation structures for large offshore wind farms

International Nuclear Information System (INIS)

Birch, C.; Gormsen, C.; Lyngesen, S.; Rasmussen, J. L.; Juhl, H.

1997-01-01

This paper presents the results of the development of a cost-efficient foundation for large (1.5 MW) offshore wind farms at water depth of 5 to 11 m. Previously, medium sized wind turbines (500 kW) in Denmark have been installed offshore at water depths of approximately 5 m on concrete gravity foundations. The installation of larger turbines at greater depth does, however, hold great promise in terms of wind environment and environmental considerations. The costs of a traditional gravity foundation at these increased water depths is expected to be prohibitive, and the aim of the project has been to reduce the foundations costs in general. This paper describes the theoretical basis for the geotechnical and structural design of three alternative concepts and presents an optimised layout of each based on a research and development project. The basis has been a wind farm consisting of 100 turbines. The R and D project has been undertaken by the consulting engineers Nellemann, Nielsen and Rauschenberger A/S (Gravity foundation), LICengineering A/S (Mono pile) and Ramboell (Tripod) in co-operation with the Danish utility engineering companies Elkraft and Elsamprojekt A/S. The project was partly financed by the participants and by the Danish Energy Agency through their 1996 Energy Research Programme (EFP-96). (au) 18 refs

What Factors Influence Wind Perceptions

Science.gov (United States)

Stein, Tatiana

Over the last decade, wind power has emerged as a possible source of energy and has attracted the attention of homeowners and policy makers worldwide. Many technological hurdles have been overcome in the last few years that make this technology feasible and economical. The United States has added more wind power than any other type of electric generation in 2012. Depending on the location, wind resources have shown to have the potential to offer 20% of the nation's electricity; a single, large wind turbine has the capacity to produce enough electricity to power 350 homes. Throughout the development of wind turbines, however, energy companies have seen significant public opposition towards the tall white structures. The purpose of this research was to measure peoples' perceptions on wind turbine development throughout their growth, from proposal to existing phase. Three hypotheses were developed based on the participant's political affiliation, proximity and knowledge of wind turbines. To validate these hypotheses, participants were asked an array of questions regarding their perception on economic, environmental, and social impacts of wind turbines with an online service called Amazon Mechanical Turk. The responses were from residents living in the United States and required them to provide their zip code for subsequent analysis. The analysis from the data obtained suggests that participants are favorable towards wind turbine development and would be supportive of using the technology in their community. Political affiliation and proximity to the nearest wind turbine in any phase of development (proposal, construction, existing) were also analyzed to determine if they had an effect on a person's overall perception on wind turbines and their technology. From the analysis, political affiliation was seen to be an indirect factor to understanding favorability towards wind turbines; the more liberal you are, the more supportive you will be towards renewable energy use

A Review of Research on Large Scale Modern Vertical Axis Wind Turbines at Uppsala University

Directory of Open Access Journals (Sweden)

Senad Apelfröjd

2016-07-01

Full Text Available This paper presents a review of over a decade of research on Vertical Axis Wind Turbines (VAWTs conducted at Uppsala University. The paper presents, among others, an overview of the 200 kW VAWT located in Falkenberg, Sweden, as well as a description of the work done on the 12 kW prototype VAWT in Marsta, Sweden. Several key aspects have been tested and successfully demonstrated at our two experimental research sites. The effort of the VAWT research has been aimed at developing a robust large scale VAWT technology based on an electrical control system with a direct driven energy converter. This approach allows for a simplification where most or all of the control of the turbines can be managed by the electrical converter system, reducing investment cost and need for maintenance. The concept features an H-rotor that is omnidirectional in regards to wind direction, meaning that it can extract energy from all wind directions without the need for a yaw system. The turbine is connected to a direct driven permanent magnet synchronous generator (PMSG, located at ground level, that is specifically developed to control and extract power from the turbine. The research is ongoing and aims for a multi-megawatt VAWT in the near future.

An Appropriate Wind Model for Wind Integrated Power Systems Reliability Evaluation Considering Wind Speed Correlations

Directory of Open Access Journals (Sweden)

Rajesh Karki

2013-02-01

Full Text Available Adverse environmental impacts of carbon emissions are causing increasing concerns to the general public throughout the world. Electric energy generation from conventional energy sources is considered to be a major contributor to these harmful emissions. High emphasis is therefore being given to green alternatives of energy, such as wind and solar. Wind energy is being perceived as a promising alternative. This source of energy technology and its applications have undergone significant research and development over the past decade. As a result, many modern power systems include a significant portion of power generation from wind energy sources. The impact of wind generation on the overall system performance increases substantially as wind penetration in power systems continues to increase to relatively high levels. It becomes increasingly important to accurately model the wind behavior, the interaction with other wind sources and conventional sources, and incorporate the characteristics of the energy demand in order to carry out a realistic evaluation of system reliability. Power systems with high wind penetrations are often connected to multiple wind farms at different geographic locations. Wind speed correlations between the different wind farms largely affect the total wind power generation characteristics of such systems, and therefore should be an important parameter in the wind modeling process. This paper evaluates the effect of the correlation between multiple wind farms on the adequacy indices of wind-integrated systems. The paper also proposes a simple and appropriate probabilistic analytical model that incorporates wind correlations, and can be used for adequacy evaluation of multiple wind-integrated systems.

Research Based on the Acoustic Emission of Wind Power Tower Drum Dynamic Monitoring Technology

Science.gov (United States)

Zhang, Penglin; Sang, Yuan; Xu, Yaxing; Zhao, Zhiqiang

Wind power tower drum is one of the key components of the wind power equipment. Whether the wind tower drum performs safety directly affects the efficiency, life, and performance of wind power equipment. Wind power tower drum in the process of manufacture, installation, and operation may lead to injury, and the wind load and gravity load and long-term factors such as poor working environment under the action of crack initiation or distortion, which eventually result in the instability or crack of the wind power tower drum and cause huge economic losses. Thus detecting the wind power tower drum crack damage and instability is especially important. In this chapter, acoustic emission is used to monitor the whole process of wind power tower drum material Q345E steel tensile test at first, and processing and analysis tensile failure signal of the material. And then based on the acoustic emission testing technology to the dynamic monitoring of wind power tower drum, the overall detection and evaluation of the existence of active defects in the whole structure, and the acoustic emission signals collected for processing and analysis, we could preliminarily master the wind tower drum mechanism of acoustic emission source. The acoustic emission is a kind of online, efficient, and economic method, which has very broad prospects for work. The editorial committee of nondestructive testing qualification and certification of personnel teaching material of science and technology industry of national defense, "Acoustic emission testing" (China Machine Press, 2005.1).

Wind power and market power in competitive markets

International Nuclear Information System (INIS)

Twomey, Paul; Neuhoff, Karsten

2010-01-01

Average market prices for intermittent generation technologies are lower than for conventional generation. This has a technical reason but can be exaggerated in the presence of market power. When there is much wind smaller amounts of conventional generation technologies are required, and prices are lower, while at times of little wind prices are higher. This effect reflects the value of different generation technologies to the system. But under conditions of market power, conventional generators with market power can further depress the prices if they have to buy back energy at times of large wind output and can increase prices if they have to sell additional power at times of little wind output. This greatly exaggerates the effect. Forward contracting does not reduce the effect. An important consequence is that allowing market power profit margins as a support mechanism for generation capacity investment is not a technologically neutral policy.

System Dynamics Simulation of Large-Scale Generation System for Designing Wind Power Policy in China

Directory of Open Access Journals (Sweden)

Linna Hou

2015-01-01

Full Text Available This paper focuses on the impacts of renewable energy policy on a large-scale power generation system, including thermal power, hydropower, and wind power generation. As one of the most important clean energy, wind energy has been rapidly developed in the world. But in recent years there is a serious waste of wind power equipment and investment in China leading to many problems in the industry from wind power planning to its integration. One way overcoming the difficulty is to analyze the influence of wind power policy on a generation system. This paper builds a system dynamics (SD model of energy generation to simulate the results of wind energy generation policies based on a complex system. And scenario analysis method is used to compare the effectiveness and efficiency of these policies. The case study shows that the combinations of lower portfolio goal and higher benchmark price and those of higher portfolio goal and lower benchmark price have large differences in both effectiveness and efficiency. On the other hand, the combinations of uniformly lower or higher portfolio goal and benchmark price have similar efficiency, but different effectiveness. Finally, an optimal policy combination can be chosen on the basis of policy analysis in the large-scale power system.

Technological assessment of local manufacturers for wind turbine blade manufacturing in Pakistan

Science.gov (United States)

Mahmood, Khurram; Haroon, General

2012-11-01

Composite materials manufacturing industry is one of the world's hi-tech industry. Manufacturing of wind turbine blades is one of the specialized fields requiring high degree of precision and composite manufacturing techniques. This paper identifies the industries specializing in the composite manufacturing and is able to manufacture wind turbines blades in Pakistan. In the second phase, their technology readiness level is determined, based on some factors and then a readiness level are assigned to them. The assigned technology readiness level will depict the absorptive capacity of each manufacturing unit and its capability to take on such projects. The individual readiness level of manufacturing unit will then be used to establish combined technology readiness level of Pakistan particularly for wind turbine blades manufacturing. The composite manufacturing industry provides many spin offs and a diverse range of products can be manufactured using this facility. This research will be helpful to categorize the strong points and flaws of local industry for the gap analysis. It can also be used as a prerequisite study before the evaluation of technologies and specialties to improve the industry of the country for the most favorable results. This will form a basic data base which can be used for the decision making related to transfer of technology, training of local skilled workers and general up-gradation of the local manufacturing units.

State of the art-hydraulic yaw systems for wind turbines

DEFF Research Database (Denmark)

Stubkier, Søren; Pedersen, Henrik C.; Andersen, Torben Ole

2011-01-01

This paper addresses the yawing systems of Horizontal Axis Wind Turbines (HAWT’s). HAWT’s represents close to all of the commercial large wind turbines sold today and must be considered state-of-the art within wind turbine technology. Two choices exists when considering components for the active ...

Current R and D needs in wind energy technology

International Nuclear Information System (INIS)

Maribo Pedersen, B.

1995-01-01

The meeting, hosted by NOVEM, the Netherlands Agency for Energy and the Environment, was attended by 22 people. The purpose of the meeting was to get an impression of how far the efforts spent until now on worldwide research and development have brought the general understanding of, and possibly solutions to, the various problems within wind energy technology - thereby providing some guidance as to where to go from now. In 1994 it was estimated that more than 100 million U.S. dollars was spent on R, D and D by those OECD countries which have a wind energy program, and that since 1974 at least 1000 mil. U.S. dollars must have been spent. The necessity of continued basic research within certain areas was recognized, and it was emphasized that the size of the research teams should always be greater than 'the critical mass'. There seemed to be consensus among all participants that the areas for continued research were the following: aerodynamics, aeroelasticity and load calculations, aeroacoustics (verification of fatigue calculation procedures for 3D stress distribution, establishing a data base of material properties), lightning protection measures, offshore installations (combined wind/wave loading, dynamics of support structures, wind and turbulence over the open sea), power conversion and wind turbine - grid interaction. (EG)

2010 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Ryan Wiser, Mark Bolinger

2011-06-01

This report provides a comprehensive overview of trends in the U.S. wind power market in 2010. The report analyzes trends in wind power capacity, industry, manufacturing, turbines, installed project costs, project performance, and wind power prices. It also describes trends among wind power developers, project owners, and power purchasers, and discusses financing issues.

European wind integration study (EWIS). Towards a successful integration of large scale wind power into European electricity grids. Final report

Energy Technology Data Exchange (ETDEWEB)

Winter, W.

2010-03-15

Large capacities of wind generators have already been installed and are operating in Germany (26GW) and Spain (16GW). Installations which are as significant in terms of proportion to system size are also established in Denmark (3.3GW), the All Island Power System of Ireland and Northern Ireland (1.5GW), and Portugal (3.4GW). Many other countries expect significant growth in wind generation such that the total currently installed capacity in Europe of 68GW is expected to at least double by 2015. Yet further increases can be expected in order to achieve Europe's 2020 targets for renewable energy. The scale of this development poses big challenges for wind generation developers in terms of obtaining suitable sites, delivering large construction projects, and financing the associated investments from their operations. Such developments also impact the networks and it was to address the immediate transmission related challenges that the European Wind Integration Study (EWIS) was initiated by Transmission System Operators (TSOs) with the objective of ensuring the most effective integration of large scale wind generation into Europe's transmission networks and electricity system. The challenges anticipated and addressed include: 1) How to efficiently accommodate wind generation when markets and transmission access arrangements have evolved for the needs of traditional controllable generation. 2) How to ensure supplies remain secure as wind varies (establishing the required backup/reserves for low wind days and wind forecast errors as well as managing network congestion in windy conditions). 3) How to maintain the quality and reliability of supplies given the new generation characteristics. 4) How to achieve efficient network costs by suitable design and operation of network connections, the deeper infrastructure including offshore connections, and crossborder interconnections. EWIS has focused on the immediate network related challenges by analysing detailed

Greenhouse gas emissions from operating reserves used to backup large-scale wind power.

Science.gov (United States)

Fripp, Matthias

2011-11-01

Wind farms provide electricity with no direct emissions. However, their output cannot be forecasted perfectly, even a short time ahead. Consequently, power systems with large amounts of wind power may need to keep extra fossil-fired generators turned on and ready to provide power if wind farm output drops unexpectedly. In this work, I introduce a new model for estimating the uncertainty in short-term wind power forecasts, and how this uncertainty varies as wind power is aggregated over larger regions. I then use this model to estimate the reserve requirements in order to compensate for wind forecast errors to a 99.999% level of reliability, and an upper limit on the amount of carbon dioxide that would be emitted if natural gas power plants are used for this purpose. I find that for regions larger than 500 km across, operating reserves will undo 6% or less of the greenhouse gas emission savings that would otherwise be expected from wind power.

2008 WIND TECHNOLOGIES MARKET REPORT

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ryan H.; Bolinger, Mark; Barbose, G.; Mills, A.; Rosa, A.; Porter, K.; Fink, S.; Tegen, S.; Musial, W.; Oteri, F.; Heimiller, D.; Rberts, B.; Belyeu, K.; Stimmel, R.

2009-07-15

The U.S. wind industry experienced a banner year in 2008, again surpassing even optimistic growth projections from years past. At the same time, the last year has been one of upheaval, with the global financial crisis impacting near-term growth prospects for the wind industry, and with federal policy changes enacted to push the industry towards continued aggressive expansion. This rapid pace of development has made it difficult to keep up with trends in the marketplace. Yet, the need for timely, objective information on the industry and its progress has never been greater. This report - the third of an ongoing annual series - attempts to meet this need by providing a detailed overview of developments and trends in the U.S. wind power market, with a particular focus on 2008. As with previous editions, this report begins with an overview of key wind power installation-related trends: trends in wind capacity growth in the U.S., how that growth compares to other countries and generation sources, the amount and percentage of wind in individual states and serving specific utilities, and the quantity of proposed wind capacity in various interconnection queues in the United States. Next, the report covers an array of wind industry trends, including developments in turbine manufacturer market share, manufacturing and supply-chain investments, wind turbine and wind project size, project financing developments, and trends among wind power developers, project owners, and power purchasers. The report then turns to a discussion of wind project price, cost, and performance trends. In so doing, it reviews the price of wind power in the United States, and how those prices compare to the cost of fossil-fueled generation, as represented by wholesale power prices. It also describes trends in installed wind project costs, wind turbine transaction prices, project performance, and operations and maintenance expenses. Next, the report examines other policy and market factors impacting the

Temporal structure of aggregate power fluctuations in large-eddy simulations of extended wind-farms

NARCIS (Netherlands)

Stevens, Richard Johannes Antonius Maria; Meneveau, Charles

2014-01-01

Fluctuations represent a major challenge for the incorporation of electric power from large wind-farms into power grids. Wind-farm power output fluctuates strongly in time, over various time scales. Understanding these fluctuations, especially their spatio-temporal characteristics, is particularly

Advanced tools for modeling, design and optimization of wind turbine systems

DEFF Research Database (Denmark)

Iov, F.; Hansen, A.D.; Jauch, C.

2005-01-01

As wind turbine technology and control has advanced over the last decade, this has led to a high penetration of wind turbines into the power system. Whether it be for a large wind turbine or an offshore wind farm with hundreds of MW power capacity, the electrical system has become more and more i...

Wind power today: 1999 Wind Energy program highlights

Energy Technology Data Exchange (ETDEWEB)

Weis-Taylor, Pat

2000-04-06

Wind Power Today is an annual publication that provides an overview for the Department of Energy's Wind Energy Program. The purpose of Wind Power Today is to show how DOE's Wind Energy Program supports wind turbine research and deployment in hopes of furthering the advancement of wind technologies that produce clean, low-cost, reliable energy for the 21st century. Content objectives include: Educate readers about the advantages and potential for widespread deployment of wind energy; explain DOE wind energy program objectives and goals; describe program accomplishments in research and application; examine the barriers to widespread deployment; describe benefits of continued research and development; facilitate technology transfer; attract cooperative wind energy projects with industry.

Evolutionary analysis of technological innovations: the example of solar photovoltaic and wind energy

International Nuclear Information System (INIS)

Taillant, Pierre

2005-01-01

The objective of this research thesis is to study the building up and the development of technologies for renewable energies considered as environmental radical innovations. In a first part, the author discusses the systemic aspects of innovation and the environmental challenges associated with energy technologies. He examines the main evolutions of energy systems over a long period. In a second part, he addresses innovation incentives in the case of environmental technologies and within the frame of the neo-classical economic theory. The next parts aim at presenting the theoretical framework of the evolutionary analysis of innovation and technical change, and at applying it to the case of technological innovations for renewable energies (photovoltaic and wind energy). World PV market trends are discussed and the technological competition context of this sector is analysed. The evolution of the solar PV technological system in Germany is discussed, as well as the specific case of development of the wind energy technological system in Denmark

Performance of automatic generation control mechanisms with large-scale wind power

Energy Technology Data Exchange (ETDEWEB)

Ummels, B.C.; Gibescu, M.; Paap, G.C. [Delft Univ. of Technology (Netherlands); Kling, W.L. [Transmission Operations Department of TenneT bv (Netherlands)

2007-11-15

The unpredictability and variability of wind power increasingly challenges real-time balancing of supply and demand in electric power systems. In liberalised markets, balancing is a responsibility jointly held by the TSO (real-time power balancing) and PRPs (energy programs). In this paper, a procedure is developed for the simulation of power system balancing and the assessment of AGC performance in the presence of large-scale wind power, using the Dutch control zone as a case study. The simulation results show that the performance of existing AGC-mechanisms is adequate for keeping ACE within acceptable bounds. At higher wind power penetrations, however, the capabilities of the generation mix are increasingly challenged and additional reserves are required at the same level. (au)

Probabilistic Aspects of Harmonic Emission of Large Offshore Wind Farms

DEFF Research Database (Denmark)

Jensen, Christian Flytkjær; Bak, Claus Leth; Kocewiak, Lukasz Hubert

2011-01-01

In this article, a new probabilistic method of as-sessment of harmonic emission of large offshore wind farms is presented. Based on measurements from the British wind farm Burbo Banks, probability density functions are estimated for the dominating low order harmonic currents injected by a single...... turbine. The degree and type of dependence between the harmonic emission and the operating point of a single turbine is established. A model of Burbo Banks, suitable for harmonic load flow studies, is created in DIgSILENT Power Factory along with a DPL-script that deals with the probabilistic issues...... of the harmonic emission. The simulated harmonic distortion at the PCC is compared to measurement. This reveals some diffi-culties regarding harmonic load flow studies. The harmonic background distortion in the grid to where the wind farm is connected must be included in the study. Furthermore, a very detailed...

Worldwide potential of wind energy

Energy Technology Data Exchange (ETDEWEB)

Flavin, C

1982-01-01

A well-documented discussion is presented dealing with the worldwide potential of wind energy as a source of electrical and mechanical power. It is pointed out that 2% of the solar insolation is converted to wind kinetic energy; it is constantly renewed and nondepletable. Efficiency of windmills are discussed (20 to 40%) and payback periods of less than 5 years are cited. Effects of wind velocity and site location are described. Wind pumps are reviewed and the need for wind pumps, particularly in the developing countries is stressed. The generation of electricity by windmills using small turbines is reviewed and appears promising in areas with wind velocities greater than 12 mi/hr. The development of large windmills and groups of windmills (windfarms) for large scale electrical power is discussed, illustrated, and reviewed (offshore sites included). Environmental and safety problems are considered as well as the role of electrical utilities, government support and research activities. It is concluded that the potential contribution of wind energy is immense and that mechanical windmills may become one of the most important renewable technologies. Electrical generating potential is estimated at 20 to 30% of electrical needs. International programs are discussed briefly. 57 references. (MJJ)

Progresses in application of computational ?uid dynamic methods to large scale wind turbine aerodynamics?

Institute of Scientific and Technical Information of China (English)

Zhenyu ZHANG; Ning ZHAO; Wei ZHONG; Long WANG; Bofeng XU

2016-01-01

The computational ?uid dynamics (CFD) methods are applied to aerody-namic problems for large scale wind turbines. The progresses including the aerodynamic analyses of wind turbine pro?les, numerical ?ow simulation of wind turbine blades, evalu-ation of aerodynamic performance, and multi-objective blade optimization are discussed. Based on the CFD methods, signi?cant improvements are obtained to predict two/three-dimensional aerodynamic characteristics of wind turbine airfoils and blades, and the vorti-cal structure in their wake ?ows is accurately captured. Combining with a multi-objective genetic algorithm, a 1.5 MW NH-1500 optimized blade is designed with high e?ciency in wind energy conversion.

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.

Integrated monitoring of wind plant systems

Science.gov (United States)

Whelan, Matthew J.; Janoyan, Kerop D.; Qiu, Tong

2008-03-01

Wind power is a renewable source of energy that is quickly gaining acceptance by many. Advanced sensor technologies have currently focused solely on improving wind turbine rotor aerodynamics and increasing of the efficiency of the blade design and concentration. Alternatively, potential improvements in wind plant efficiency may be realized through reduction of reactionary losses of kinetic energy to the structural and substructural systems supporting the turbine mechanics. Investigation of the complete dynamic structural response of the wind plant is proposed using a large-scale, high-rate wireless sensor network. The wireless network enables sensors to be placed across the sizable structure, including the rotating blades, without consideration of cabling issues and the economic burden associated with large spools of measurement cables. A large array of multi-axis accelerometers is utilized to evaluate the modal properties of the system as well as individual members and would enable long-term structural condition monitoring of the wind turbine as well. Additionally, environmental parameters, including wind speed, temperature, and humidity, are wirelessly collected for correlation. Such a wireless system could be integrated with electrical monitoring sensors and actuators and incorporated into a remote multi-turbine centralized plant monitoring and control system.

Assessing offshore wind potential

International Nuclear Information System (INIS)

Adelaja, Adesoji; McKeown, Charles; Calnin, Benjamin; Hailu, Yohannes

2012-01-01

Quantifying wind potential is a pivotal initial step in developing and articulating a state’s policies and strategies for offshore wind industry development. This is particularly important in the Great Lakes States where lessons from other offshore environments are not directly applicable. This paper presents the framework developed for conducting a preliminary assessment of offshore wind potential. Information on lake bathymetry and wind resources were combined in simulating alternative scenarios of technically feasible turbine construction depths and distance concerns by stakeholders. These yielded estimates of developable offshore wind areas and potential power generation. While concerns about the visibility of turbines from shore reduce the power that can be generated, engineering solutions that increase the depths at which turbines can be sited increase such potential power output. This paper discusses the costs associated with technical limitations on depth and the social costs related to public sentiments about distance from the shoreline, as well as the possible tradeoffs. The results point to a very large untapped energy resource in the Michigan’s Great Lakes, large enough to prompt policy action from the state government. - Highlights: ▶ We build a theoretical framework for modeling offshore wind power production. ▶ Illustration of the impact of technology and social limitations on offshore wind energy development. ▶ Geospatial modeling of the offshore wind potential of the Great Lakes.

Line Capacity Expansion and Transmission Switching in Power Systems With Large-Scale Wind Power

DEFF Research Database (Denmark)

Villumsen, Jonas Christoffer; Bronmo, Geir; Philpott, Andy B.

2013-01-01

In 2020 electricity production from wind power should constitute nearly 50% of electricity demand in Denmark. In this paper we look at optimal expansion of the transmission network in order to integrate 50% wind power in the system, while minimizing total fixed investment cost and expected cost...... of power generation. We allow for active switching of transmission elements to reduce congestion effects caused by Kirchhoff's voltage law. Results show that actively switching transmission lines may yield a better utilization of transmission networks with large-scale wind power and increase wind power...

2013 Wind Technologies Market Report

Energy Technology Data Exchange (ETDEWEB)

Wiser, R.; Bolinger, M.; Barbose, G.; Darghouth, N.; Hoen, B.; Mills, A.; Weaver, S.; Porter, K.; Buckley, M.; Oteri, F.; Tegen, S.

2014-08-01

This annual report provides a detailed overview of developments and trends in the U.S. wind power market, with a particular focus on 2013. This 2013 edition updates data presented in previous editions while highlighting key trends and important new developments. The report includes an overview of key installation-related trends; trends in wind power capacity growth; how that growth compares to other countries and generation sources; the amount and percentage of wind energy in individual states; the status of offshore wind power development and the quantity of proposed wind power capacity in various interconnection queues in the United States.

Wind and Photovoltaic Large-Scale Regional Models for hourly production evaluation

DEFF Research Database (Denmark)

Marinelli, Mattia; Maule, Petr; Hahmann, Andrea N.

2015-01-01

This work presents two large-scale regional models used for the evaluation of normalized power output from wind turbines and photovoltaic power plants on a European regional scale. The models give an estimate of renewable production on a regional scale with 1 h resolution, starting from a mesosca...... of the transmission system, especially regarding the cross-border power flows. The tuning of these regional models is done using historical meteorological data acquired on a per-country basis and using publicly available data of installed capacity.......This work presents two large-scale regional models used for the evaluation of normalized power output from wind turbines and photovoltaic power plants on a European regional scale. The models give an estimate of renewable production on a regional scale with 1 h resolution, starting from a mesoscale...

Large-scale wind power in New Brunswick : a regional scenario study towards 2025

International Nuclear Information System (INIS)

2008-08-01

This paper discussed the large-scale development of wind power in New Brunswick and evaluated Danish experiences with wind development as a template for developing wind resources in the Maritimes region. The study showed that New Brunswick and the Maritimes region have good wind resources, and that the province will gain significant economic benefits from deploying between 5500 and 7500 MW of wind power capacity by 2025. Wind power development will contribute to the security of supply in the region and reduce air pollution. Carbon regulation and renewable portfolio standards will improve the competitiveness of wind power. Electricity generated by wind power plants in the Maritimes can be sold to other provinces in Canada, as well as to the heavily populated New England region of the United States. A high level of cooperation between markets in the Maritimes area and neighbouring New England and Quebec systems will be required in addition to load flow analyses of electricity systems. Denmark's experiences with developing wind power indicate that existing market designs must be restructured to allow for higher levels of competition. A strong system operator is required to integrate wind power into the system. It was concluded that strong political leadership is required to ensure the sustainable development of the region. 5 refs., 4 tabs., 9 figs

DOE/NREL supported wind energy activities in Alaska

Energy Technology Data Exchange (ETDEWEB)

Drouilhet, S.

1997-12-01

This paper describes three wind energy projects implemented in Alaska. The first, a sustainable technology energy partnerships (STEP) wind energy deployment project in Kotzebue will install 6 AOC 15/50 wind turbines and connect to the existing village diesel grid, consisting of approximately 1 MW average load. It seeks to develop solutions to the problems of arctic wind energy installations (transport, foundations, erection, operation, and maintenance), to establish a wind turbine test site, and to establish the Kotzebue Electric Association as a training and deployment center for wind/diesel technology in rural Alaska. The second project, a large village medium-penetration wind/diesel system, also in Kotzebue, will install a 1-2 MW windfarm, which will supplement the AOC turbines of the STEP project. The program will investigate the impact of medium penetration wind energy on power quality and system stability. The third project, the Alaska high-penetration wind/diesel village power pilot project in Wales will install a high penetration (80-100%) wind/diesel system in a remote Alaskan village. The system will include about 180 kW installed wind capacity, meeting an average village load of about 60 kW. This program will provide a model for high penetration wind retrofits to village diesel power systems and build the capability in Alaska to operate, maintain, and replicate wind/diesel technology. The program will also address problems of: effective use of excess wind energy; reliable diesel-off operation; and the role of energy storage.

IEA Wind Task 26. Wind Technology, Cost, and Performance Trends in Denmark, Germany, Ireland, Norway, the European Union, and the United States: 2007–2012

Energy Technology Data Exchange (ETDEWEB)

Vitina, Aisma [Ea Energy Analyses, Copenhagen (Denmark); Lüers, Silke [Deutsche WindGuard, Varel (Germany); Wallasch, Anna-Kathrin [Deutsche WindGuard, Varel (Germany); Berkhout, Volker [Fraunhofer IWES, Kassel (Germany); Duffy, Aidan [Dublin Inst. of Technology and Dublin Energy Lab. (Ireland); Cleary, Brendan [Dublin Inst. of Technology and Dublin Energy Lab. (Ireland); Husabø, Lief I. [Norwegian Water Resources and Energy Directorate (NVE), Oslo (Norway); Weir, David E. [Norwegian Water Resources and Energy Directorate (NVE), Oslo (Norway); Lacal-Arántegui, Roberto [European Commission, Ispra (Italy). Joint Research Centre; Hand, Maureen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lantz, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Belyeu, Kathy [Belyeu Consulting, Takoma Park, MD (United States); Wiser, Ryan H [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hoen, Ben [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-06-01

The International Energy Agency Implementing Agreement for cooperation in Research, Development, and Deployment of Wind Energy Systems (IEA Wind) Task 26—The Cost of Wind Energy represents an international collaboration dedicated to exploring past, present and future cost of wind energy. This report provides an overview of recent trends in wind plant technology, cost, and performance in those countries that are currently represented by participating organizations in IEA Wind Task 26: Denmark, Germany, Ireland, Norway, and the United States as well as the European Union.

Analytical Model for Mean Flow and Fluxes of Momentum and Energy in Very Large Wind Farms

Science.gov (United States)

Markfort, Corey D.; Zhang, Wei; Porté-Agel, Fernando

2018-01-01

As wind-turbine arrays continue to be installed and the array size continues to grow, there is an increasing need to represent very large wind-turbine arrays in numerical weather prediction models, for wind-farm optimization, and for environmental assessment. We propose a simple analytical model for boundary-layer flow in fully-developed wind-turbine arrays, based on the concept of sparsely-obstructed shear flows. In describing the vertical distribution of the mean wind speed and shear stress within wind farms, our model estimates the mean kinetic energy harvested from the atmospheric boundary layer, and determines the partitioning between the wind power captured by the wind turbines and that absorbed by the underlying land or water. A length scale based on the turbine geometry, spacing, and performance characteristics, is able to estimate the asymptotic limit for the fully-developed flow through wind-turbine arrays, and thereby determine if the wind-farm flow is fully developed for very large turbine arrays. Our model is validated using data collected in controlled wind-tunnel experiments, and its usefulness for the prediction of wind-farm performance and optimization of turbine-array spacing are described. Our model may also be useful for assessing the extent to which the extraction of wind power affects the land-atmosphere coupling or air-water exchange of momentum, with implications for the transport of heat, moisture, trace gases such as carbon dioxide, methane, and nitrous oxide, and ecologically important oxygen.

Small wind power plants : results of the Nordic wind diesel projects for large telecommunications companies; Implantation d'une centrale eolienne comme source d'energie d'appoint pour des stations de telecommunications

Energy Technology Data Exchange (ETDEWEB)

Ilinca, A.; Chaumel, J.L. [ATI Eolien, Rimouski, PQ (Canada); Thibault, G. [Entreprises MB, PQ (Canada)

2005-07-01

Two wind-diesel generating stations have been installed at telecommunication towers in the remote communities of Kuujjuarapik and Lac Julien in northern Quebec. The use of wind power contributes to the sustainable development in these remote areas by lowering the reliance on costly helicopter-transported diesel fuel and by reducing the release of greenhouse gases to the atmosphere. The technical characteristics of the Bergey 100 kW turbine with battery charger were presented along with the technical characteristics of the EolDie control panel that controls the supply of electricity from either the wind or diesel power generators. For the first time, the ATI-Wind technology system that was installed can supply the needs of the large telecommunication towers of Bell Canada and Telebec from either the wind or the diesel generators. The system is also capable of shutting down the diesel generators when wind energy is sufficient to take over. Early results from June 2005 showed that the diesel generators could be turned off for 55 per cent of the time. Preliminary results of these 2 projects were discussed by the firms in charge of the diesel and wind aspects and recommendations for improvements to the control systems were presented. 11 figs.

Quadrennial Technology Review 2015: Technology Assessments--Wind Power

Energy Technology Data Exchange (ETDEWEB)

none,

2015-10-07

Wind power has become a mainstream power source in the U.S. electricity portfolio, supplying 4.9% of the nation’s electricity demand in 2014. With more than 65 GW installed across 39 states at the end of 2014, utility-scale wind power is a cost-effective source of low-emissions power generation throughout much of the nation. The United States has significant sustainable land-based and offshore wind resource potential, greater than 10 times current total U.S. electricity consumption. A technical wind resource assessment conducted by the Department of Energy (DOE) in 2009 estimated that the land-based wind energy potential for the contiguous United States is equivalent to 10,500 GW capacity at 80 meters (m) hub and 12,000 GW capacity at 100 meters (m) hub heights, assuming a capacity factor of at least 30%. A subsequent 2010 DOE report estimated the technical offshore wind energy potential to be 4,150 GW. The estimate was calculated from the total offshore area within 50 nautical miles of shore in areas where average annual wind speeds are at least 7 m per second at a hub height of 90 m.

Valuation framework for large scale electricity storage in a case with wind curtailment

International Nuclear Information System (INIS)

Loisel, Rodica; Mercier, Arnaud; Gatzen, Christoph; Elms, Nick; Petric, Hrvoje

2010-01-01

This paper investigates the value of large scale applications of electricity storage in selected European power systems in the context of wind generation confronted with a grid bottleneck. It analyzes the market value to 2030 of two storage technologies, assuming the market situation projected for Germany and France. The analysis assesses the evolution of storage economics based on the net present value of cash flows. Sensitivities to market and regulatory drivers of value are assessed, e.g. electricity price spreads, ancillary services revenues, wind curtailment and the level of carbon prices. The paper concludes by suggesting possible ways to improve the competitiveness of electricity storage, such as research and development and deployment programmes, and changes to the design of power markets and regulatory arrangements to enable storage owners to better capture the benefits of storage. Such changes would allow electricity storage, where economically viable, to play a critical role in establishing a future sustainable European power system. - Research highlights: →CAES and PHS are not cost-effective for current market design in France and Germany → Market reforms are run to reward bottleneck avoiding and ancillary reserves → Storage is profitable when all potential socio-economic benefits are aggregated → R and D and D programs for storage improvement are economically and socially justified.

Probabilistic aspects of harmonic emission of large offshore wind farms

Energy Technology Data Exchange (ETDEWEB)

Jensen, Christian F. [Energinet.dk, Fredericia (Denmark); Bak, Claus L. [Aalborg Univ. (Denmark). Dept. of Energy Technology; Kocewiak, Lukasz; Hjerrild, Jesper [DONG Energy, Skaerbaek (Denmark); Berthelsen, Kasper K. [Aalborg Univ. (Denmark). Dept. of Mathematical Sciences

2011-07-01

In this article, a new probabilistic method of assessment of harmonic emission of large offshore wind farms is presented. Based on measurements from the British wind farm Burbo Banks, probability density functions are estimated for the dominating low order harmonic currents injected by a single turbine. The degree and type of dependence between the harmonic emission and the operating point of a single turbine is established. A model of Burbo Banks, suitable for harmonic load flow studies, is created in DIgSILENT Power Factory along with a DPL-script that deals with the probabilistic issues of the harmonic emission. The simulated harmonic distortion at the PCC is compared to measurement. This reveals some difficulties regarding harmonic load flow studies. The harmonic background distortion in the grid to where the wind farms is connected must be included in the study. Furthermore, a very detailed representation of the frequency dependent short circuit impedance must be used before sufficiently accurate results can be obtained from the model. (orig.)

Application of bamboo laminates in large-scale wind turbine blade design?

Institute of Scientific and Technical Information of China (English)

Long WANG; Hui LI; Tongguang WANG

2016-01-01

From the viewpoint of material and structure in the design of bamboo blades of large-scale wind turbine, a series of mechanical property tests of bamboo laminates as the major enhancement materials for blades are presented. The basic mechanical characteristics needed in the design of bamboo blades are brie?y introduced. Based on these data, the aerodynamic-structural integrated design of a 1.5 MW wind turbine bamboo blade relying on a conventional platform of upwind, variable speed, variable pitch, and doubly-fed generator is carried out. The process of the structural layer design of bamboo blades is documented in detail. The structural strength and fatigue life of the designed wind turbine blades are certified. The technical issues raised from the design are discussed. Key problems and direction of the future study are also summarized.

Materials of large wind turbine blades: Recent results in testing and modeling

DEFF Research Database (Denmark)

Mishnaevsky, Leon; Brøndsted, Povl; Nijssen, Rogier

2012-01-01

The reliability of rotor blades is the pre-condition for the development and wide use of large wind turbines. In order to accurately predict and improve the wind turbine blade behavior, three main aspects of the reliability and strength of rotor blades were considered: (i) development of methods...... of the effect of the microstructure of wind turbine blade composites on their strength and ways of microstructural optimization of the materials. By testing reference coupons, the effect of testing parameters (temperature and frequency) on the lifetime of blade composites was investigated, and the input data...... clustering, misalignments, interface properties and other factors on the strength and lifetime of the wind turbine blade materials were investigated in the micromechanical finite element simulations. The results described in this paper stem from the Rotor Structure and Materials task of the UPWIND project...

A cooling concept for improved field winding performance in large superconducting ac generators

International Nuclear Information System (INIS)

Laskaris, T.E.

1977-01-01

An analytical study of a flow circuit for large superconducting generator rotors is presented. The flow circuit provides regulation of the level of liquid in the rotor externally by adjusting the helium supply pressure. It also protects the vapour cooled structural members of the rotor from overcooling during transient periods of operation. Furthermore, it is capable of reducing the winding temperature below 4.2 K thereby enhancing the superconductor's performance. For example, a large generator rotor with NbTi superconducting field winding experiences approximately a 50% increase in its critical current density compared to that at 4.2 K. (author)

Static Aeroelastic Deformation Effects in Preliminary Wind-tunnel Tests of Silent Supersonic Technology Demonstrator

OpenAIRE

Makino, Yoshikazu; Ohira, Keisuke; Makimoto, Takuya; Mitomo, Toshiteru; 牧野, 好和; 大平, 啓介; 牧本, 卓也; 三友, 俊輝

2011-01-01

Effects of static aeroelastic deformation of a wind-tunnel test model on the aerodynamic characteristics are discussed in wind-tunnel tests in the preliminary design phase of the silent supersonic technology demonstrator (S3TD). The static aeroelastic deformation of the main wing is estimated for JAXA 2m x 2m transonic wind-tunnel and 1m x 1m supersonic wind-tunnel by a finite element method (FEM) structural analysis in which its structural model is tuned with the model deformation calibratio...

Summary Report: The Shadow effect of large wind farms: measurements, data analysis and modelling

DEFF Research Database (Denmark)

Frandsen, Sten Tronæs; Barthelmie, Rebecca Jane; Rathmann, Ole

It was the goal of the project – by means of data from the demonstration wind farms Horns Rev and Nysted, analyses of these data and modelling – to facilitate prediction of the power losses from a wind farm should a new wind farm be built upwind relative to the prevailing wind direction...... it may appropriate to build new wind farms rather close to the existing wind farms. A relevant question is therefore how far away new wind farms must be placed to avoid too large power losses. Measurements have been carried out for several years at the two sites, and databases have been prepared....... Thus, if different modelling efforts results in comparable results, the quality of the models will be tested outside the physical range where data are available. All considered the project participants find that the project has been immensely successful. The main achievements of the project are...

Operation and control of large wind turbines and wind farms. Final report

DEFF Research Database (Denmark)

Sørensen, Poul Ejnar; Hansen, Anca Daniela; Thomsen, Kenneth

2005-01-01

good power quality and limit mechanical loads and life time consumption. The projectdeveloped models for 3 different concepts for wind farms. Two of the concepts use active stall controlled wind turbines, one with AC connection and one with modern HVDC/VSC connection of the wind farm. The third concept...... is based on pitch controlled windturbines using doubly fed induction generators. The models were applied to simulate the behaviour of the wind farm control when they were connected to a strong grid, and some initial simulations were performed to study the behaviour of the wind farms whenit was isolated...... concepts. The potentials of optimising the lifetime/energy production ratio by means of using revised operational strategies for the individual wind turbines are investigated. Different strategies have beensimulated, where the power production is decreased to an optimum when taking loads and actual price...

Wind Power Today: 2000 Wind Energy Program Highlights

Energy Technology Data Exchange (ETDEWEB)

Weis-Taylor, W.

2001-05-08

Wind Power Today is an annual publication that provides an overview of the U.S. Department of Energy's Wind Energy Program. The purpose of Wind Power Today is to show how DOE's Wind Energy Program supports wind turbine research and deployment in hopes of furthering the advancement of wind technologies that produce clean, low-cost, reliable energy. Content objectives include: educate readers about the advantages and potential for widespread deployment of wind energy; explain the program's objectives and goals; describe the program's accomplishments in research and application; examine the barriers to widespread deployment; describe the benefits of continued research and development; facilitate technology transfer; and attract cooperative wind energy projects with industry.

Wind-induced circulation in a large tropical lagoon: Chetumal Bay

Science.gov (United States)

Palacios, E.; Carrillo, L.

2013-05-01

Chetumal Bay is a large tropical lagoon located at the Mesoamerican Reef System. Windinduced circulation in this basin was investigated by using direct measurements of current, sea level, and 2d barotropic numerical model. Acoustic Doppler Profiler (ADP) transects covering the north of Chetumal Bay during two campaigns September 2006 and March 2007 were used. The 2d barotropic numerical model was ROMs based and wind forced. Wind information was obtained from a meteorological station located at ECOSUR Chetumal. Sea level data was collected from a pressure sensor deployed in the lagoon. A seasonal pattern of circulation was observed. From observations, during September 2006, a northward flow was shown in most part of the bay and a southward flow in the eastern coast was observed with velocities ranged from 6 cm s-1 to 36 cm s-1. In March 2007, the current pattern was more complex; divergences and converges were identified. The dominant circulation was northward in eastern portion, and southward in the central and western zone. The average current speed was 6 cm s-1 with maximum values of 26 -34 cm s-1. During September 2006 predominant wind was easternsoutheastern and during March 2007, northerly wind events were recorded. Sea level amplitude responded quickly to changes in the magnitude and direction of the wind. Results of sea level and circulation from the 2d barotropic numerical model agreed with observations at first approximation.

Impact of wind power in autonomous power systems—power fluctuations—modelling and control issues

DEFF Research Database (Denmark)

Margaris, Ioannis D.; Hansen, Anca Daniela; Cutululis, Nicolaos Antonio

2011-01-01

for diesel and steam generation plants are applied. The power grid, including speed governors, automatic voltage regulators, protection system and loads is modelled in the same platform. Results for different load and wind profile cases are being presented for the case study of the island Rhodes, in Greece......This paper describes a detailed modelling approach to study the impact of wind power fluctuations on the frequency control in a non-interconnected system with large-scale wind power. The approach includes models for wind speed fluctuations, wind farm technologies, conventional generation...... technologies, power system protection and load. Analytical models for wind farms with three different wind turbine technologies, namely Doubly Fed Induction Generator, Permanent Magnet Synchronous Generator and Active Stall Induction Generator-based wind turbines, are included. Likewise, analytical models...

Integration of 18 GW Wind Energy into the Energy Market. Practical Experiences in Germany. Experiences with large-scale integration of wind power into power systems

International Nuclear Information System (INIS)

Krauss, C.; Graeber, B.; Lange, M.; Focken, U.

2006-01-01

This work describes the integration of 18 GW of wind power into the German energy market. The focus lies on reporting practical experiences concerning the use of wind energy in Germany within the framework of the renewable energy act (EEG) and the immediate exchange of wind power between the four German grid control areas. Due to the EEG the demand for monitoring the current energy production of wind farms and for short-term predictions of wind power has significantly increased and opened a broader market for these services. In particular for trading on the intraday market ultra short term predictions in the time frame of 1 to 10 hours require different approaches than usual dayahead predictions because the large numerical meteorological models are not sufficiently optimized for very short time horizons. It is shown that for this range a combination of a statistical and a deterministic model leads to significant improvements and stable results as it unites the characteristics of the current wind power production with the synoptic-scale meteorological situation. The possible concepts of balancing the remaining differences between predicted and actual wind power generation are discussed. As wind power prediction errors and load forecasting errors are uncorrelated, benefits can arise from a combined balancing. Finally practical experiences with wind power fluctuations and large forecast errors are presented.

Validity of VR Technology on the Smartphone for the Study of Wind Park Soundscapes

Directory of Open Access Journals (Sweden)

Tianhong YU

2018-04-01

Full Text Available The virtual reality of the landscape environment supplies a high level of realism of the real environment, and may improve the public awareness and acceptance of wind park projects. The soundscape around wind parks could have a strong influence on the acceptance and annoyance of wind parks. To explore this VR technology on realism and subjective responses toward different soundscapes of ambient wind parks, three different types of virtual reality on the smartphone tests were performed: aural only, visual only, and aural–visual combined. In total, 21 aural and visual combinations were presented to 40 participants. The aural and visual information used were of near wind park settings and rural spaces. Perceived annoyance levels and realism of the wind park environment were measured. Results indicated that most simulations were rated with relatively strong realism. Perceived realism was strongly correlated with light, color, and vegetation of the simulation. Most wind park landscapes were enthusiastically accepted by the participants. The addition of aural information was found to have a strong impact on whether the participant was annoyed. Furthermore, evaluation of the soundscape on a multidimensional scale revealed the key components influencing the individual’s annoyance by wind parks were the factors of “calmness/relaxation” and “naturality/pleasantness”. “Diversity” of the soundscape might correlate with perceived realism. Finally, the dynamic aural–visual stimuli using virtual reality technology could improve the environmental assessment of the wind park landscapes, and thus, provide a more comprehensible scientific decision than conventional tools. In addition, this study could improve the participatory planning process for more acceptable wind park landscapes.

FACTS Devices for Large Wind Power Plants

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz; Teodorescu, Remus; Rodriguez, Pedro

2010-01-01

Growing number of wind turbines is changing electricity generation profile all over the world. However, high wind energy penetration affects power system safety and stability. For this reason transmission system operators (TSO) impose more stringent connection requirements on the wind power plant...

Wind and wave extremes over the world oceans from very large ensembles

Science.gov (United States)

Breivik, Øyvind; Aarnes, Ole Johan; Abdalla, Saleh; Bidlot, Jean-Raymond; Janssen, Peter A. E. M.

2014-07-01

Global return values of marine wind speed and significant wave height are estimated from very large aggregates of archived ensemble forecasts at +240 h lead time. Long lead time ensures that the forecasts represent independent draws from the model climate. Compared with ERA-Interim, a reanalysis, the ensemble yields higher return estimates for both wind speed and significant wave height. Confidence intervals are much tighter due to the large size of the data set. The period (9 years) is short enough to be considered stationary even with climate change. Furthermore, the ensemble is large enough for nonparametric 100 year return estimates to be made from order statistics. These direct return estimates compare well with extreme value estimates outside areas with tropical cyclones. Like any method employing modeled fields, it is sensitive to tail biases in the numerical model, but we find that the biases are moderate outside areas with tropical cyclones.

Offshore wind investments – Realism about cost developments is necessary

International Nuclear Information System (INIS)

Schwanitz, Valeria Jana; Wierling, August

2016-01-01

Data available from the recent boom in European offshore wind investments contradict widely held expectations about a decline in costs per kW. Our review shows that scenario projections for investment costs are systematically flawed by over-optimistic assumptions. Contrasting offshore wind technology with onshore wind and nuclear power, we argue that offshore wind could be a candidate for negative learning since a trend towards more complex OWP (offshore wind parks) exists and uncertainty remains high. We estimate technical uncertainty and input cost uncertainty to calculate whether investments in offshore wind technology are profitable today. Applying a real option model to two reference plants using empirically derived parameter values, we allow for sunk cost and the possibility to abandon the investment. We find that for a large parameter range, investments are not profitable, even with substantial support such as feed-in tariffs under the German Energy Act. Therefore, policy incentives for building larger and more complex offshore wind parks bear a high risk to fail in their aim of bringing down investment costs. Policies that instead incentivize the optimization of offshore wind technology – in particular by increasing the load factor and material efficiency and bringing down decommissioning costs – are more sustainable. - Highlights: • We review offshore wind power investments. • Contrary to expectations costs increase. • It is unlikely to see a turn in the near future as complexity is growing. • We deploy an empirically based real option model. • Investments are not profitable across a large parameter range.

Superconducting magnets technologies for large accelerator

International Nuclear Information System (INIS)

Ogitsu, Toru

2017-01-01

The first hadron collider with superconducting magnet technologies was built at Fermi National Accelerator Laboratory as TEVATRON. Since then, the superconducting magnet technologies are widely used in large accelerator applications. The paper summarizes the superconducting magnet technologies used for large accelerators. (author)

Detecting, categorizing and forecasting large romps in wind farm power output using meteorological observations and WPPT

DEFF Research Database (Denmark)

Cutler, N.; Kay, M.; Jacka, K.

2007-01-01

The Wind Power Prediction Tool (WPPT) has been installed in Australia for the first time, to forecast the power output from the 65MW Roaring 40s Renewable Energy P/L Woolnorth Bluff Point wind form. This article analyses the general performance of WPPT as well as its performance during large romps...... (swings) in power output. In addition to this, detected large ramps are studied in detail and categorized. WPPT combines wind speed and direction forecasts from the Australian Bureau of Meteorology regional numerical weather prediction model, MesoLAPS, with real-time wind power observations to make hourly...... forecasts of the wind farm power output. The general performances of MesoLAPS and WPPTore evaluated over I year using the root mean square error (RMSE). The errors are significantly lower than for basic benchmark forecasts but higher than for many other WPPT installations, where the site conditions...

Field evaluation of remote wind sensing technologies: Shore-based and buoy mounted LIDAR systems

Energy Technology Data Exchange (ETDEWEB)

Herrington, Thomas [Stevens Inst. of Technology, Hoboken, NJ (United States)

2017-11-03

will be transferred to the Garrad Hassan (a subcontractor to Fishermen’s Energy) for incorporation in to the validation database, which is accessible to other scientific team members. Data collection times and durations will be determined by the PI and Co-PIs in consultation with instrument engineers to ensure the capture of data representative of the expected range of mid-Atlantic atmospheric conditions (e.g., temperature, moisture, coastal low pressure systems, tropical systems, rain, snow, fog). The collection and processing of the data is a function of site specific measurement requirements (Kelley et.al. 2007; Hannon et.al. 2008). To determine the optimal profiles of wind speed and direction from the LIDAR radial velocities as a function of azimuth angle, rigorous estimates of the bias and random error of each radial velocity estimate are required. Lockheed Martin Coherent Technologies, Inc., under contract with Fishermen’s Energy, will provide analyses of raw and processed data using various scan patterns to determine optimal performance settings for the pulsed scanning LIDAR. Once optimized, appropriate processing and analyses techniques will be evaluated by Garrad Hassan for use in validating the accuracy of the LIDAR wind field measurements against the standard anemometer measurements from the meteorological masts. The most attractive capability of the scanning LIDAR is the ability to provide high spatial resolution observations in a three-dimensional volume which provides superior statistical accuracy due to the large number of samples obtained. Each radial scan provides measurements in 100 range gates over a distance of 10 to 12 km at an update rate of 5 to 10 Hz and rotation of 2.5° per second. Each rotation at a fixed azimuth requires 2.4 minutes. Depending on the number of azimuths desired a complete scan can take up to 10 minutes or longer to complete. Once collected the radial velocities are processed to produce vector wind velocity estimates based

Wind energy. Energy technologies in national, European and global perspective

International Nuclear Information System (INIS)

Hauge Madsen, P.; Bjerregaard, E.T.D.

2002-01-01

According to a recent study, global wind generating capacity increased by some 6800 MW in 2001, an annual growth of just over half the corresponding figure for 2000. 2001 was the third consecutive year in which new wind power capacity exceeded new nuclear power capacity, showing the maturity of wind power technology. Total installed wind power worldwide by the end of 2001 was close to 25.000 MW. Germany, Spain and Denmark are the main players, accounting for 56% of the world's capacity increase in 2001 and a total cumulative installed capacity of 14.750 MW, or 59% of the global total. The USA and India are also significant users of wind power; in 2001 the USA added 1700 MW of new installed capacity to become the world's second-largest market for wind power. The report Wind Force 10 outlines a scenario in which wind power provides 10% of the world's electricity by 2020, corresponding to a total installed capacity of 1200 GW. Risoe's System Analysis Department has looked at the possible future costs of electricity produced by wind turbines compared to conventional power. A learning curve analysis of historical data results in a progress ratio of 0,85. This means that for every doubling of the installed capacity, the cost of wind-generated electricity is reduced by 15%. Until recently the main driver for wind power has been a concern for greenhouse gases. Security of energy supply has now become an important issue, however, especially in Europe and the USA. Wind power plants can be erected at short notice and in a modular fashion that allows capacity to be added as required. The European Commission has supported wind power by sponsoring international research co-operation between institutes, universities and equipment manufacturers. The IEA supports worldwide co-operation, and has recently issued a report on the longterm R and D needs of wind energy. Denmark has, mainly financed by the Danish Energy Agency, taken part in the IEA's R and D Wind international co

Harmonics in large offshore wind farms

DEFF Research Database (Denmark)

Kocewiak, Lukasz Hubert

and nature of various harmonic components. A comprehensive comparison of harmonic voltages and currents based on probability distribution estimation and appropriate statistics calculation (mean, variance, probability density function, etc.) is applied. Such approach gives a better overview and comparison...... and analysis, and ϐinally ending up on modelling and models application. Different aspects of validation in time domain, frequency domain, and by application of statistical methods are mentioned in relation to respective problems. Measurements constitute a core part in industry-oriented research. Due...... that it is of great importance to know the nature of generated harmonics in large offshore wind farms in order to apply the most suitable data processing technique. Time-frequency analysis based on multiresolution wavelet transform is used in order to perform time-frequency domain analysis helpful to distinguish...

Modelling and Measuring Flow and Wind Turbine Wakes in Large Wind Farms Offshore

DEFF Research Database (Denmark)

Barthelmie, Rebecca Jane; Hansen, Kurt Schaldemose; Frandsen, Sten Tronæs

2009-01-01

power losses due to wakes and loads. The research presented is part of the EC-funded UpWind project, which aims to radically improve wind turbine and wind farm models in order to continue to improve the costs of wind energy. Reducing wake losses, or even reduce uncertainties in predicting power losses...

Wind Energy Resource Atlas of Mongolia

Energy Technology Data Exchange (ETDEWEB)

Elliott, D; Schwartz, M; Scott, G.; Haymes, S.; Heimiller, D.; George, R.

2001-08-27

The United States Department of Energy (DOE) and the United States Agency for International Development (USAID) sponsored a project to help accelerate the large-scale use of wind energy technologies in Mongolia through the development of a wind energy resource atlas of Mongolia. DOE's National Renewable Energy Laboratory (NREL) administered and conducted this project in collaboration with USAID and Mongolia. The Mongolian organizations participating in this project were the Scientific, Production, and Trade Corporation for Renewable Energy (REC) and the Institute of Meteorology and Hydrology (IMH). The primary goals of the project were to develop detailed wind resource maps for all regions of Mongolia for a comprehensive wind resource atlas, and to establish a wind-monitoring program to identify prospective sites for wind energy projects and help validate some of the wind resource estimates.

Topology and Technology Survey on Medium Voltage Power Converters for Large Wind Turbines

DEFF Research Database (Denmark)

Sztykiel, Michal; Teodorescu, Remus; Munk-Nielsen, Stig

2011-01-01

Based on state-of-the-art within generator and power converter designs, this paper presents and justifies the most promising converter circuitries and concepts for future 10 MW wind turbines. In order to reduce losses and increase efficiency of the turbine, it is assumed that the bulky step...... by various circuit configurations of previously defined power modules....

Development of large scale and wind energy conservation system. Operational studies on a large-scale wind energy conservation system; Ogata furyoku hatsuden system no kaihatsu. Ogata furyoku hatsuden system no unten kenkyu

Energy Technology Data Exchange (ETDEWEB)

Takita, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

1994-12-01

Described herein are the results of the FY1994 research program for operational studies on a large-scale wind energy conversion system. A total of 8 domestic and foreign cases are studied for wind energy conversion cost, to clarify the causes for higher cost of the Japanese system. The wind power systems studied include Japanese (5 units at Tappi Wind Park, the same type supplied by company M), US (California Wind Farm, 300 units) and UK (Wales Wind Farm, 103 units) systems. The investment costs are 639, 285 and 189 thousand yen/kW for the Japanese, US and UK systems, respectively. It is also revealed that the power plant itself and assembling costs account for a majority (70 to 88%) of the total investment cost. The higher cost of the Japanese system results from a smaller number of units installed, and the power plant cost can be drastically reduced by mass production. Increasing size also reduces cost greatly.

A ``Cyber Wind Facility'' for HPC Wind Turbine Field Experiments

Science.gov (United States)

Brasseur, James; Paterson, Eric; Schmitz, Sven; Campbell, Robert; Vijayakumar, Ganesh; Lavely, Adam; Jayaraman, Balaji; Nandi, Tarak; Jha, Pankaj; Dunbar, Alex; Motta-Mena, Javier; Craven, Brent; Haupt, Sue

2013-03-01

The Penn State ``Cyber Wind Facility'' (CWF) is a high-fidelity multi-scale high performance computing (HPC) environment in which ``cyber field experiments'' are designed and ``cyber data'' collected from wind turbines operating within the atmospheric boundary layer (ABL) environment. Conceptually the ``facility'' is akin to a high-tech wind tunnel with controlled physical environment, but unlike a wind tunnel it replicates commercial-scale wind turbines operating in the field and forced by true atmospheric turbulence with controlled stability state. The CWF is created from state-of-the-art high-accuracy technology geometry and grid design and numerical methods, and with high-resolution simulation strategies that blend unsteady RANS near the surface with high fidelity large-eddy simulation (LES) in separated boundary layer, blade and rotor wake regions, embedded within high-resolution LES of the ABL. CWF experiments complement physical field facility experiments that can capture wider ranges of meteorological events, but with minimal control over the environment and with very small numbers of sensors at low spatial resolution. I shall report on the first CWF experiments aimed at dynamical interactions between ABL turbulence and space-time wind turbine loadings. Supported by DOE and NSF.

Aerodynamic flow deflector to increase large scale wind turbine power generation by 10%.

Science.gov (United States)

2015-11-01

The innovation proposed in this paper has the potential to address both the efficiency demands of wind farm owners as well as to provide a disruptive design innovation to turbine manufacturers. The aerodynamic deflector technology was created to impr...

Some answers to power generation lie blowing in the wind

Energy Technology Data Exchange (ETDEWEB)

1975-10-02

An assessment of wind power generation schemes by the Energy Technology Support Unit is reported. The capital cost of large, efficient windmills should be around 100--200 Pounds per installed kW and an optimum size for a single wind rotor would be 1 MW.

Heliosphere Responds to a Large Solar Wind Intensification: Decisive Observations from IBEX

Science.gov (United States)

McComas, D. J.; Dayeh, M. A.; Funsten, H. O.; Heerikhuisen, J.; Janzen, P. H.; Reisenfeld, D. B.; Schwadron, N. A.; Szalay, J. R.; Zirnstein, E. J.

2018-03-01

Our heliosphere—the bubble in the local interstellar medium produced by the Sun’s outflowing solar wind—has finally responded to a large increase in solar wind output and pressure in the second half of 2014. NASA’s Interstellar Boundary Explorer (IBEX) mission remotely monitors the outer heliosphere by observing energetic neutral atoms (ENAs) returning from the heliosheath, the region between the termination shock and heliopause. IBEX observed a significant enhancement in higher energy ENAs starting in late 2016. While IBEX observations over the previous decade reflected a general reduction of ENA intensities, indicative of a deflating heliosphere, new observations show that the large (∼50%), persistent increase in the solar wind dynamic pressure has modified the heliosheath, producing enhanced ENA emissions. The combination of these new observations with simulation results indicate that this pressure is re-expanding our heliosphere, with the termination shock and heliopause already driven outward in the locations closest to the Sun. The timing between the IBEX observations, a large transient pressure enhancement seen by Voyager 2, and the simulations indicates that the pressure increase propagated through the heliosheath, reflected off the heliopause, and the enhanced density of the solar wind filled the heliosheath behind it before generating significantly enhanced ENA emissions. The coming years should see significant changes in anomalous cosmic rays, galactic cosmic radiation, and the filtration of interstellar neutral atoms into the inner heliosphere.

Towards mass-market development of wind energy

International Nuclear Information System (INIS)

Palz, W.

1996-01-01

The wind turbine technologies employed in today's markets for wind energy are innovative, efficient and in many cases cost competitive. A world market of more than 1000 MW/year and with a turnover of 1 billion ECU has developed and 30,000 new jobs have been created, most of them in small and medium size enterprises. 80% of today's world production is European. The preferred turbine capacity of today is 500 kW. In the next few years a three-fold increase in the rated power of most commercial machines to 1.5 MW is expected. The new large machines have been achieved through the ''WEGA''-programme of the European Commission. Significant market penetration of wind power in the European Union is very recent. The 2500 MW installed wind capacity in Europe today accounts only for 1/2% of the total capacity available for electricity production. Markets of the future will depend on a better development of the economic integration issues of wind energy into large networks. A key is the cost of electric grids which conditions the opportunity cost for feeding wind power at any particular point into the grids. Also, better predictability of the wind resource will give higher value to wind power in the grid and improve its economics further. Various financing schemes have been set up throughout Europe. Financial support and incentives are vital for some more years to come to expand current markets and improve economics through economy of scale. The utilisation of wind turbines in off-grid situations is an important new field for technological innovations and deployment. (author)

A new approach to wind energy: Opportunities and challenges

Science.gov (United States)

Dabiri, John O.; Greer, Julia R.; Koseff, Jeffrey R.; Moin, Parviz; Peng, Jifeng

2015-03-01

Despite common characterizations of modern wind energy technology as mature, there remains a persistent disconnect between the vast global wind energy resource—which is 20 times greater than total global power consumption—and the limited penetration of existing wind energy technologies as a means for electricity generation worldwide. We describe an approach to wind energy harvesting that has the potential to resolve this disconnect by geographically distributing wind power generators in a manner that more closely mirrors the physical resource itself. To this end, technology development is focused on large arrays of small wind turbines that can harvest wind energy at low altitudes by using new concepts of biology-inspired engineering. This approach dramatically extends the reach of wind energy, as smaller wind turbines can be installed in many places that larger systems cannot, especially in built environments. Moreover, they have lower visual, acoustic, and radar signatures, and they may pose significantly less risk to birds and bats. These features can be leveraged to attain cultural acceptance and rapid adoption of this new technology, thereby enabling significantly faster achievement of state and national renewable energy targets than with existing technology alone. Favorable economics stem from an orders-of-magnitude reduction in the number of components in a new generation of simple, mass-manufacturable (even 3D-printable), vertical-axis wind turbines. However, this vision can only be achieved by overcoming significant scientific challenges that have limited progress over the past three decades. The following essay summarizes our approach as well as the opportunities and challenges associated with it, with the aim of motivating a concerted effort in basic and applied research in this area.

Spatial correlation of atmospheric wind at scales relevant for large scale wind turbines

Science.gov (United States)

Bardal, L. M.; Sætran, L. R.

2016-09-01

Wind measurements a short distance upstream of a wind turbine can provide input for a feedforward wind turbine controller. Since the turbulent wind field will be different at the point/plane of measurement and the rotor plane the degree of correlation between wind speed at two points in space both in the longitudinal and lateral direction should be evaluated. This study uses a 2D array of mast mounted anemometers to evaluate cross-correlation of longitudinal wind speed. The degree of correlation is found to increase with height and decrease with atmospheric stability. The correlation is furthermore considerably larger for longitudinal separation than for lateral separation. The integral length scale of turbulence is also considered.

The challenge of integrating large scale wind power

Energy Technology Data Exchange (ETDEWEB)

Kryszak, B.

2007-07-01

The support of renewable energy sources is one of the key issues in current energy policies. The paper presents aspects of the integration of wind power in the electric power system from the perspective of a Transmission System Operator (TSO). Technical, operational and market aspects related to the integration of more than 8000 MW of installed wind power into the Transmission Network of Vattenfall Europe Transmission are discussed, and experiences with the transmission of wind power, wind power prediction, balancing of wind power, power production behaviour and fluctuations are reported. Moreover, issues for wind power integration on a European level will be discussed with the background of a wind power study. (auth)

Managing Critical Weather Conditions in a Large-Scale Wind Based European Power System - The TWENTIES Project

DEFF Research Database (Denmark)

Detlefsen, N.; Sørensen, Poul Ejnar; Eriksen, P.

2011-01-01

the cut-off wind speed (typically 25 m/s). Experience has shown that a large offshore wind farm in this way can be shut down from full power to zero power in less than 5 minutes. Thus, in the planned offshore development in the North Sea, several GW of wind power could be shut down within less than one...

Transient Stability Assessment of Power System with Large Amount of Wind Power Penetration

DEFF Research Database (Denmark)

Liu, Leo; Chen, Zhe; Bak, Claus Leth

2012-01-01

Recently, the security and stability of power system with large amount of wind power are the concerned issues, especially the transient stability. In Denmark, the onshore and offshore wind farms are connected to distribution system and transmission system respectively. The control and protection...... methodologies of onshore and offshore wind farms definitely affect the transient stability of power system. In this paper, the onshore and offshore wind farms are modeled in detail in order to assess the transient stability of western Danish power system. Further, the computation of critical clearing time (CCT...... plants, load consumption level and high voltage direct current (HVDC) transmission links are taken into account. The results presented in this paper are able to provide an early awareness of power system security condition of the western Danish power system....

Assessment of research needs for wind turbine rotor materials technology

National Research Council Canada - National Science Library

National Research Council Staff; Commission on Engineering and Technical Systems; Division on Engineering and Physical Sciences; National Research Council; National Academy of Sciences

1991-01-01

... on Assessment of Research Needs for Wind Turbine Rotor Materials Technology Energy Engineering Board Commission on Engineering and Technical Systems National Research Council NATIONAL ACADEMY PRESS Washington, D.C. 1991 Copyrightthe true use are Please breaks Page inserted. accidentally typesetting been have may original the from errors not...

Numerical Simulations of the Aeroelastic Behavior of Large Horizontal-Axis Wind Turbines: The Drivetrain Case

DEFF Research Database (Denmark)

Gebhardt, Cristian; Veluri, Badrinath; Preidikman, Sergio

2010-01-01

In this work an aeroelastic model that describes the interaction between aerodynamics and drivetrain dynamics of a large horizontal–axis wind turbine is presented. Traditional designs for wind turbines are based on the output of specific aeroelastic simulation codes. The output of these codes giv...

Impacts of large amounts of wind power on design and operation of power systems, results of IEA collaboration

DEFF Research Database (Denmark)

Holttinen, Hannele; Meibom, Peter; Orths, Antje

2011-01-01

There are dozens of studies made and ongoing related to wind integration. However, the results are not easy to compare. IEA WIND R&D Task 25 on Design and Operation of Power Systems with Large Amounts of Wind Power collects and shares information on wind generation impacts on power systems......, with analyses and guidelines on methodologies. In the state-of-the-art report (October, 2007), and the final report of the 3 years period (July, 2009) the most relevant wind power grid integration studies have been analysed especially regarding methodologies and input data. Several issues that impact...... on the amount of wind power that can be integrated have been identified. Large balancing areas and aggregation benefits of wide areas help in reducing the variability and forecast errors of wind power as well as help in pooling more cost effective balancing resources. System operation and functioning...

Room for wind. An investigation into the possibilities for the erection of large numbers of wind turbines. Ruimte voor wind. Een studie naar de plaatsingsmogelijkheden van grote aantallen windturbines

Energy Technology Data Exchange (ETDEWEB)

Arkesteijn, L; Van Huis, G; Reckman, E

1987-01-01

The Dutch government aims to realize a wind power capacity in The Netherlands of 1000 MW in the year 2000. Environmental impacts of the erection of a large number of 200 kW and 1 MW wind turbines are studied. Four siting models have been developed in which attention is paid to environmental and economic aspects, the possibilities to introduce the electric power into the national power grid and the availability and reliability of enough wind. Noise pollution and danger for birds are to be avoided. The choice between the construction of wind parks where a number of wind turbines is concentrated in a small area or a more dispersed construction is somewhat difficult if all relevant factors are to be taken into consideration. Without government's interference the target of 1000 MW in the year 2000 will probably not be attained. It is therefore desirable to practise an active energy policy in favor of wind energy, for which many ways are possible.

Wind energy. Energy technologies in national, European and global perspective

Energy Technology Data Exchange (ETDEWEB)

Hauge Madsen, P.; Bjerregaard, E.T.D. [Risoe National Lab., Wind Energy Dept., Roskilde (Denmark)

2002-10-01

According to a recent study, global wind generating capacity increased by some 6800 MW in 2001, an annual growth of just over half the corresponding figure for 2000. 2001 was the third consecutive year in which new wind power capacity exceeded new nuclear power capacity, showing the maturity of wind power technology. Total installed wind power worldwide by the end of 2001 was close to 25.000 MW. Germany, Spain and Denmark are the main players, accounting for 56% of the world's capacity increase in 2001 and a total cumulative installed capacity of 14.750 MW, or 59% of the global total. The USA and India are also significant users of wind power; in 2001 the USA added 1700 MW of new installed capacity to become the world's second-largest market for wind power. The report Wind Force 10 outlines a scenario in which wind power provides 10% of the world's electricity by 2020, corresponding to a total installed capacity of 1200 GW. Risoe's System Analysis Department has looked at the possible future costs of electricity produced by wind turbines compared to conventional power. A learning curve analysis of historical data results in a progress ratio of 0,85. This means that for every doubling of the installed capacity, the cost of wind-generated electricity is reduced by 15%. Until recently the main driver for wind power has been a concern for greenhouse gases. Security of energy supply has now become an important issue, however, especially in Europe and the USA. Wind power plants can be erected at short notice and in a modular fashion that allows capacity to be added as required. The European Commission has supported wind power by sponsoring international research co-operation between institutes, universities and equipment manufacturers. The IEA supports worldwide co-operation, and has recently issued a report on the longterm R and D needs of wind energy. Denmark has, mainly financed by the Danish Energy Agency, taken part in the IEA's R and D Wind

The application of suction caisson technology to offshore wind turbines

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-09-15

A mathematical model describing the behaviour of caisson foundations for offshore wind turbines has been developed. The model has been verified and calibrated through laboratory and field work. Simultaneously, conceptual designs of wind turbine foundations incorporating suction caissons were studied using the same model. It was concluded that much of the seabed around Britain is well suited to the use of caissons and monopod and quadropod structures are superior to tripods. Although suction caissons are vulnerable to scour, rock dumping can largely eliminate this potential problem. The next phase will be to install a fully instrumented full-scale prototype to monitor the effects of wind and waves. The main contractor was SLP Engineering Limited and about 75 per cent of the funding came from the DTI.

A Statistical Model for Hourly Large-Scale Wind and Photovoltaic Generation in New Locations

DEFF Research Database (Denmark)

Ekstrom, Jussi; Koivisto, Matti Juhani; Mellin, Ilkka

2017-01-01

The analysis of large-scale wind and photovoltaic (PV) energy generation is of vital importance in power systems where their penetration is high. This paper presents a modular methodology to assess the power generation and volatility of a system consisting of both PV plants (PVPs) and wind power...... of new PVPs and WPPs in system planning. The model is verified against hourly measured wind speed and solar irradiance data from Finland. A case study assessing the impact of the geographical distribution of the PVPs and WPPs on aggregate power generation and its variability is presented....

Experimental study of the impact of large-scale wind farms on land–atmosphere exchanges

International Nuclear Information System (INIS)

Zhang Wei; Markfort, Corey D; Porté-Agel, Fernando

2013-01-01

Large-scale wind farms, covering a significant portion of the land and ocean surface, may affect the transport of momentum, heat, mass and moisture between the atmosphere and the land locally and globally. To understand the wind-farm–atmosphere interaction, we conducted wind-tunnel experiments to study the surface scalar (heat) flux using model wind farms, consisting of more than ten rows of wind turbines—having typical streamwise and spanwise spacings of five and four rotor diameters—in a neutral boundary layer with a heated surface. The spatial distribution of the surface heat flux was mapped with an array of surface heat flux sensors within the quasi-developed regime of the wind-farm flow. Although the overall surface heat flux change produced by the wind farms was found to be small, with a net reduction of 4% for a staggered wind farm and nearly zero change for an aligned wind farm, the highly heterogeneous spatial distribution of the surface heat flux, dependent on the wind-farm layout, was significant. The difference between the minimum and maximum surface heat fluxes could be up to 12% and 7% in aligned and staggered wind farms, respectively. This finding is important for planning intensive agriculture practice and optimizing farm land use strategy regarding wind energy project development. The well-controlled wind-tunnel experiments presented in this study also provide a first comprehensive dataset on turbulent flow and scalar transport in wind farms, which can be further used to develop and validate new parameterizations of surface scalar fluxes in numerical models. (letter)

Fundamentals for remote structural health monitoring of wind turbine blades - a preproject. Annex A. Cost-benefit for embedded sensors in large wind turbine blades

OpenAIRE

Hansen, L.G.; Lading, Lars

2002-01-01

This report contains the results of a cost-benefit analysis for the use of embed-ded sensors for damage detection in large wind turbine blades - structural health monitoring - (in connection with remote surveillance) of large wind turbine placedoff-shore. The total operating costs of a three-bladed 2MW turbine placed offshore either without sensors or with sensors are compared. The price of a structural health monitoring system of a price of 100 000 DKK (per tur-bine) results in a break-event...

Wind energy

International Nuclear Information System (INIS)

Kotevski, Darko

2003-01-01

Wind is not only free, it is inexhaustible. Wind energy has come a very long way since the prototypes of just 20 years ago. today's wind turbines are state-of-the-art technology - modular and quick to install anywhere where there is sufficient wind potential to provide secure, centralised or distributed generation. It is a global phenomenon, the world's fastest growing energy sector, a clean and effective modern technology that completely avoids pollution and thus reducing the 'green house' effect. (Original)

Harmonic Stability and Resonance Analysis in Large PMSG-Based Wind Power Plants

DEFF Research Database (Denmark)

Ebrahimzadeh, Esmaeil; Blaabjerg, Frede; Wang, Xiongfei

2018-01-01

Compared to the conventional power systems, large Wind Power Plants (WPPs) present a more challenging system where the interactions between the passive elements and the wideband control systems of power converters may result in harmonic instability and new resonance frequencies. Most of researches...... system and the resonance frequencies are identified based on the element amplitudes of the MIMO matrix. An active damping controller is used to set the poles of the WPP in a desired location in order to mitigate the harmonic instability problems. Multiple case studies are provided to depict that Wind...

A fiber-optic ice detection system for large-scale wind turbine blades

Science.gov (United States)

Kim, Dae-gil; Sampath, Umesh; Kim, Hyunjin; Song, Minho

2017-09-01

Icing causes substantial problems in the integrity of large-scale wind turbines. In this work, a fiber-optic sensor system for detection of icing with an arrayed waveguide grating is presented. The sensor system detects Fresnel reflections from the ends of the fibers. The transition in Fresnel reflection due to icing gives peculiar intensity variations, which categorizes the ice, the water, and the air medium on the wind turbine blades. From the experimental results, with the proposed sensor system, the formation of icing conditions and thickness of ice were identified successfully in real time.

Blowing in the Wind: A Review of Wind Power Technology

Science.gov (United States)

Harris, Frank

2014-01-01

The use of wind as a replenishable energy resource has come back into favour in recent decades. It is much promoted as a viable, clean energy option that will help towards reducing CO[subscript 2] emissions in the UK. This article examines the history of wind power and considers the development of wind turbines, together with their economic,…

The role of government in the development and diffusion of renewable energy technologies: Wind power in the United States, California, Denmark and Germany, 1970--2000

Science.gov (United States)

Sawin, Janet Laughlin

2001-07-01

This dissertation seeks to determine the role of government policy in advancing the development and diffusion of renewable energy technologies, and to determine if specific policies or policy types are more effective than others in achieving these ends. This study analyzes legislation, regulations, research and development (R&D) programs and their impacts on wind energy in California, the rest of the United States, Denmark and Germany, from 1970 through 2000. These countries (and state) were chosen because each has followed a very different path and has adopted wind energy at different rates. Demand for energy, particularly electricity, is rising rapidly worldwide. Renewable energy technologies could meet much of the world's future demand for electricity without the national security, environmental and social costs of conventional technologies. But renewables now play only a minor role in the electric generation systems of most countries. According to conventional economic theory, renewable energy will achieve greater market penetration once it is cost-competitive with conventional generation. This dissertation concludes, however, that government policy is the most significant causal variable in determining the development and diffusion of wind energy technology. Policy is more important for bringing wind energy to maturity than a nation's wind resource potential, wealth, relative differences in electricity prices, or existing infrastructure. Further, policy is essential for enabling a technology to succeed in the marketplace once it is cost-competitive. Policies can affect a technology's perceived, or real, costs; they can reduce risks or increase the availability and affordability of capital; appropriate and consistent policies can eliminate barriers to wind technology. To be adopted on a large scale, renewables require effective, appropriate and, above all, consistent policies that are legislated with a long-term view toward advancing a technology and an

Soil-Structure Interaction For Nonslender, Large-Diameter Offshore Monopiles

DEFF Research Database (Denmark)

Sørensen, Søren Peder Hyldal

Strong political and industrial forces, especially in Northern Europe, support the development of new technologies as well as improvements of existing technologies within the field of renewable energy. Offshore wind power is a domestic, sustainable and largely untapped energy resource. Today......, the modern offshore wind turbine offers competitive production prices compared to other sources of renewable energy. Therefore, it is a key technology in breaking the dependence on fossil fuels and in achieving the energy and climate goals of the future. For offshore wind turbines, the costs of foundation...... typically constitutes 20-30 % of the total costs. Hence, improved methods for the design of foundations for offshore wind turbines can increase the competitiveness of offshore wind energy significantly. The monopile foundation concept has been employed as the foundation for the majority of the currently...

Offshore Wind Power Planning in Korea

DEFF Research Database (Denmark)

Seo, Chul Soo; Cha, Seung-Tae; Park, Sang Ho

2012-01-01

this possible, Korea has announced the National offshore power roadmap and is now in pursuit. However, large scale offshore wind farms can incur many problems, such as power quality problems, when connecting to a power system.[1][2] Thus, KEPCO is on the process of a research study to evaluate the effects...... that connecting offshore wind power generation to a power system has on the power system. This paper looks over offshore wind power planning in Korea and describes the development of impact assessment technology of offshore wind farms.......Wind power generation is globally recognized as the most universal and reliable form of renewable energy. Korea is currently depending mostly on coal and petroleum to generate electrical power and is now trying to replace them with renewable energy such as offshore wind power generation. To make...

A study of supply-chain capabilities in the Canadian wind power industry

International Nuclear Information System (INIS)

Wittholz, H.; Pan, D.

2004-11-01

In recent years, Canadian wind energy has developed to a total installed capacity of 439 MW. It is possible that by 2012, the cumulative installed wind power capacity may reach 5,600 MW, representing an investment of $8.4 billion. This analysis of the supply-chain structure in the life cycle of a wind farm identified many potential areas where Canadian companies can offer services. Opportunities for both manufacturers and service providers were presented. It was emphasized that although wind energy is a growth industry, Canada has not participated in the development and commercialization of large wind turbine technology. The technical barriers facing Canadian suppliers regarding wind turbine generator (WTG) assembly and component manufacturing were presented. Currently, Canada imports all large WTGs and components. In order to maximize benefits to the Canadian economy, it was recommended that Canadian companies acquire European technology through licences, joint ventures or foreign investment. Technology transfer funding, training and technical assistance funding, tax incentives for capital equipment and support to universities and colleges were also recommended. It was suggested that Canadian companies should focus on manufacturing rotor blades, towers, base frames, nacelle covers and spinners, flexible drive shafts, disk brakes, vibration mounts, inverters, control cabinets, and generators. tabs., figs

Análisis preliminar del Límite de Potencia Eólica para grandes perturbaciones utilizando aerogeneradores de velocidad fija; Partial analysis of wind power limit for large disturbance using fixed speed wind turbine

Directory of Open Access Journals (Sweden)

Ariel Santos Fuentefria

2015-04-01

Full Text Available El Límite de Potencia Eólica (LPE es la cantidad de potencia eólica que permite un sistema sin perder la estabilidad y depende principalmente de las características de los generadores eólicos y de las características del sistema en términos de debilidad. Conocer el comportamiento del sistema en régimen transitorio es sumamente importante; entre las condiciones que generan mayores problemas se encuentran el cortocircuito en las líneas de mayor transferencia de potenciay la salida de algún generador del sistema. El LPE cambia para cada condición y conocer el LPE considerando estas condiciones permite aprovechar al máximo la energía del viento. En el presente trabajo se analiza el comportamiento de generadores eólicos de velocidad fija para diversas condiciones transitorias de la red, utilizándose el sistema de prueba de 14 nodos de la IEEE para verificar la metodología en uso para el análisis a través de simulaciones implementadas en el software libre PSAT.  The amount of wind power that allow an electric network without losing his stability as known as wind power limit. The wind power limit fundamentally depends on the wind turbine technology and the weakness level of the system. To know the system behaviors in dynamic performance having into account the worst disturbance is a very important matter, a short circuit in one of the most power transference line or the loss of a large generation unit was a large disturbance that can affect system stability. The wind power limit may change with the nature of the disturbance. To know the wind power limit considering this conditions allow use the wind at maximum level. In the present paper the behavior of fixed speed wind turbine for different fault types is analyzed, at those conditions, the wind power is increasing until the system become voltage unstable. For the analysis the IEEE 14 Bus Test Case is used. The Power System Analysis Toolbox (PSAT package is used for the simulation.