Energy Technology Data Exchange (ETDEWEB)
In 1994, after four years of preparation, the first off-shore wind farm in the Netherlands was erected. The ``Lely`` wind farm comprises four NedWind 500 kW wind turbines, of rotor diameter 40.77 m. The turbines are placed on unique single-pile foundations. An interesting engineering aspect of the project is the interaction between the foundations and the turbine. (author)
1996-09-01
The effects of upwind turbine wakes on the performance of a FloWind 17-m vertical-axis wind turbine (VAWT) were investigated through a series of field experiments conducted at the FloWind wind farm on Cameron Ridge, Tehachapi, California. From the field m...
1988-01-01
CleverFarm - A SuperSCADA system for wind farms
Energy Technology Data Exchange (ETDEWEB)
The CleverFarm project started out to build an integrated monitoring system for wind farms, where all information would be available and could be used across the wind farm for maintenance and component health assessments. This would enable wind farm operators to prioritise their efforts, since they have a good view of the farm status from home. A large emphasis was placed on the integration of condition monitoring approaches in the central system, enabling estimates of the remaining lifetime of components, especially in the nacelle. During the 3,5 years of the project, software and hardware was developed and installed in two wind farms in Denmark and Germany. The connected hardware included two different condition monitoring systems based on vibration sensors from ...
2004-08-01
Use of a tethersonde measurement system to conduct a Doppler SODAR performance audit
Energy Technology Data Exchange (ETDEWEB)
With the increased usage of dispersion models that require stack top wind information, such as the Complex Terrain Dispersion Model (CTDM), the need for a reliable method to collect elevated wind data has also increased. Doppler Sound Detection and Ranging (SODAR) instruments have gained recognition as a viable means of collecting such data. SODAR technology has improved greatly over the last decade and is now a cost effective alternative to tall meteorological towers. SODARs are remote sensing devices that sample the atmosphere and calculate wind speed and wind direction data at different altitudes. This is accomplished by measuring the doppler shift of an acoustic pulse emitted by a ground level antenna.
1994-12-31
Energy Technology Data Exchange (ETDEWEB)
On the Dutch North Sea coast, at the Westereems wind farm, the energy supplier Essent is currently implementing one of Europe's largest repowering projects. A total of 88 new wind turbines are going up at Dollart Bay. (orig.)
2009-07-01
Public perceptions of wind energy developments: Case studies from New Zealand
Energy Technology Data Exchange (ETDEWEB)
Although the public generally hold positive attitudes towards wind energy, proposals for the construction of new wind farms are often met with strong resistance. In New Zealand, where the government has recently introduced ambitious policy targets for renewable energy generation, negative perceptions of wind farms are increasingly evident and have the potential to prevent the achievement of these targets. This research sets out to examine what influences social resistance to wind farms in New Zealand. Drawing from public submissions on three wind farm proposals, a framework developed by Devine-Wright [Devine-Wright, P., 2005a. Beyond NIMBYism: towards an integrated Framework for Understanding Public Perceptions of Wind Energy. Wind Energy 8, 125-139.] was ...
2009-09-15
Public perceptions of wind energy developments. Case studies from New Zealand
Energy Technology Data Exchange (ETDEWEB)
Although the public generally hold positive attitudes towards wind energy, proposals for the construction of new wind farms are often met with strong resistance. In New Zealand, where the government has recently introduced ambitious policy targets for renewable energy generation, negative perceptions of wind farms are increasingly evident and have the potential to prevent the achievement of these targets. This research sets out to examine what influences social resistance to wind farms in New Zealand. Drawing from public submissions on three wind farm proposals, a framework developed by Devine-Wright [Devine-Wright, P., 2005a. Beyond NIMBYism: towards an integrated Framework for Understanding Public Perceptions of Wind Energy. Wind Energy 8, 125-139.] was ...
2009-09-15
Harbour porpoises on Horns Reef - Effects of the Horns Reef wind farm. Annual status report 2003
Energy Technology Data Exchange (ETDEWEB)
Occurrence and distribution of harbour porpoises (Phocoena phocoena) in and around the off-shore wind farm on Horns Reef, Denmark, was investigated. This report describes data collected in 2003 as part of an ongoing monitoring program, covering a period before construction of the wind farm (baseline), the construction period in 2002 and one year following construction of the wind farm. Data from acoustic dataloggers (T-PODs) and visual surveys conducted from ships confirmed the presence of harbour porpoises inside the wind farm area during all periods investigated. Comparison with baseline data from 1999-2001 and with control areas outside the wind farm did not show a statistical significant change in sighting rates inside the wind farm ...
2004-06-15
Energy Technology Data Exchange (ETDEWEB)
The first offshore wind farm in Sweden; Bockstigen, consists of five 500 kW stall controlled wind turbines on mono pile foundations. The main objectives of the technical evaluation are to verify the original design assumptions made for a load carrying mono pile and bedrock, investigate offshore power production versus onshore ditto as well as to determine park effects and analyse meteorological multi-mast statistics which serve as reference data to a newly developed computer code for offshore wind energy potential mapping. The 'main' measurement system has continuously been acquiring data at 1 and 20 Hz/channel since the summer of 1998. A 40 m meteorological mast was built within the wind farm in the summer of 1999 in order to acquire relatively undisturbed wind speed data from 'free' sectors as well as to ...
2001-12-01
Forecasting for utility-scale wind farms. The power model challenge
Energy Technology Data Exchange (ETDEWEB)
As the penetration of wind energy continues to increase around the world, with a trend towards large utility-scale wind farms (greater than 100 MW), effective wind energy forecasting will become increasingly important. Previous work by GH has estimated the trading benefit of high quality short-term forecasting to be EUR 7/MWh. Depending on market conditions, for a 100 MW wind farm with a capacity factor of 30%, this equates to an estimated annual trading benefit of up to EUR 1.8m. To date, a number of studies have focused on the mathematical modelling techniques for forecasting the production from wind farms, looking predominantly at the task of predicting the meteorological conditions at the site. This paper focuses on the final stage of the forecasting process, conversion from a meteorological forecast to a power ...
2008-07-01
Harvesting operations and energetics of tall grasses for biomass energy production: a case study
Energy Technology Data Exchange (ETDEWEB)
Florida imports about 85% of its energy needs. Among the renewable energy sources available, biomass appears promising in Florida because of a favourable environment for production and the available methods to convert biomass to energy. Optimal production of biomass requires the identification and management of high yielding persistent perennial cultivars. Elephantgrass (Pennisetum purpureum Schum.) and energycane (Saccharum spontaneum L.) are two tall grasses that meet these requirements. To optimize the supply of convertible biomass, suitable methods of harvesting the crop must be available. The purpose of this research was to study the feasibility and energetics of harvesting, drying and baling tall grasses with conventional farm machinery. A Mathews rotary scythe and a New Holland 849 Auto Wrap large round baler were determined to provide a practical harvesting system for baled biomass averaging 15-27 Mg ha [sup -1]. ...
1992-01-01
International Nuclear Information System (INIS)
Reliability has an impact on wind energy project costs and benefits. Both life test data and field failure data can be used for reliability analysis. In wind energy industry, wind farm operators have greater interest in recording wind turbine operating data. However, field failure data may be tainted or incomplete, and therefore it needs a more general mathematical model and algorithms to solve the model. The aim of this paper is to provide a solution to this problem. A three-parameter Weibull failure rate function is discussed for wind turbines and the parameters are estimated by maximum likelihood and least squares. Two populations of German and Danish wind turbines are analyzed. The traditional Weibull failure rate function is also employed for comparison. Analysis shows that the three-parameter Weibull function can obtain more accuracy ...
2009-06-01
Wind power data transmission challenges; Les defis de la transmission de donnees en eolien
Energy Technology Data Exchange (ETDEWEB)
This presentation outlined the corporate history of the Ohmega Group, a small company from Gaspe, Quebec which offers consulting services to the automation and telecommunication sector. It was created in 1982 and has been involved with the wind power industry since 1996. The main services provided by Ohmega Group include electrical and mechanical construction and maintenance services. This paper also reviewed the benefits of using Supervisory Control and Data Acquisition (SCADA) systems in the wind power industry to monitor, control and collect data from wind turbines. The Ohmega Group has provided consulting services to Cartier Wind Energy Inc., a company that was awarded several wind turbine projects by Hydro-Quebec Distribution. The Ohmega Group applied the SCADA system at the Baie des Sables, Anse a Valleau and Carleton wind turbine arrays. The typical ...
2008-07-01
A Reduced Wind Power Grid Model for Research and Education
Energy Technology Data Exchange (ETDEWEB)
A reduced grid model of a transmission system with a number of central power plants, consumption centers, local wind turbines and a large offshore wind farm is developed and implemented in the simulation tool PowerFactory (DIgSILENT). The reduced grid model is given by Energinet.dk, Transmission System Operator of Denmark (TSO) for Natural Gas and Electricity, to the Danish Universities and the Risoe National Laboratory. Its intended usage is education and studying of interaction between electricity-producing wind turbines and a realistic transmission system. Focus in these studies is on voltage stability issues and on the ride-through capability of different wind turbine concepts, equipped with advanced controllers, developed by the Risoe National Laboratory.
2006-07-01
Fish schooling as a basis for vertical axis wind turbine farm design
International Nuclear Information System (INIS)
Most wind farms consist of horizontal axis wind turbines (HAWTs) due to the high power coefficient (mechanical power output divided by the power of the free-stream air through the turbine cross-sectional area) of an isolated turbine. However when in close proximity to neighboring turbines, HAWTs suffer from a reduced power coefficient. In contrast, previous research on vertical axis wind turbines (VAWTs) suggests that closely spaced VAWTs may experience only small decreases (or even increases) in an individual turbine's power coefficient when placed in close proximity to neighbors, thus yielding much higher power outputs for a given area of land. A potential flow model of inter-VAWT interactions is developed to investigate the effect of changes in VAWT spatial arrangement on the array performance coefficient, which compares the expected average power coefficient of turbines in an array to a spatially ...
2010-09-01
Power control for wind turbines in weak grids: Concepts development
Energy Technology Data Exchange (ETDEWEB)
Presently, high wind potentials in remote areas may not be utilized for electricity production due to limited grid transmission capacity and/or difficulties in matching the electricity production with the demand. The overall project objective is to help overcome these bottlenecks, i.e. to identify and analyze methods and technologies for making it viable to utilize more of the wind potential in remote areas. The suggestion is to develop a power control concept for wind turbines which will even out the power fluctuations and make it possible to increase the wind energy penetration. The main options are to combine wind power with a pumped hydro power storage or with an AC/DC converter and battery storage. The AC/DC converter can either be an `add-on` type or it can be designed as an integrated part of a variable speed wind turbine. The idea is that combining ...
1999-03-01
Proceedings of CanWEA's 2006 conference and trade show
International Nuclear Information System (INIS)
The Canadian wind energy industry is experiencing rapid and unprecedented growth. The year 2006 saw the installation of 534 MW of wind energy across Canada, representing approximately $1 billion in new investment. It is anticipated that the wind energy industry will help to create jobs and training opportunities for many Canadians, as well as provide ongoing economic benefits to local communities through municipal tax and land lease payments. However, many challenges remain if Canada is to meet, or exceed, its objective of a total of 10,000 MW in installed wind energy by 2015. This conference provided a forum for wind industry member, academics and representatives of both governmental and non-governmental agencies to discuss issues related to wind energy development. The conference was divided into 3 streams. The policy stream examined issues related to the ...
2006-10-22
USDA Finances Wind for Rural Economic Development (Poster)
Energy Technology Data Exchange (ETDEWEB)
To foster rural economic development and growth, Congress passed the Renewable Energy Systems and Energy Efficiency Improvements Program as Section 9006 of the 2002 Farm Bill. This program provides financial assistance to farmers, ranchers, and rural small businesses to purchase renewable energy systems or make energy efficiency improvements. The Rural Business and Cooperative Services of the United States Department of Agriculture (USDA) administers this program. This conference poster provides an overview of Section 9006.
2005-05-01
Dounreay: an alternative development
International Nuclear Information System (INIS)
With the Government decision to phase out the Fast Reactor at Dounreay there is a need to find alternative employment in the area. Traditionally Caithness is an area of farming, fishing and tourism which could be damaged if Dounreay were to be made a nuclear waste repository. The suggestion is that Dounreay should become a centre for research, development and subsequent manufacture of renewable energy sources and devices to harness renewable energy. The Scottish coastline has potential for wind and wave power developments and this could lead to a whole industry in the future. (UK).
1991-01-01
Power control for wind turbines in weak grids: Project summary
Energy Technology Data Exchange (ETDEWEB)
In many parts of the world and certainly in Europe large areas exist where the wind resources are good or very good and the grid is relatively weak due to a small population. In the areas the capacity of the grid can very often be a limiting factor for the exploitation of the wind resource. There are two main problems concerned with wind power and weak grids. The first is the steady state voltage level. The other main problem is voltage fluctuations. Some or all the these problems can be avoided if a so-called power control concept is applied together with the wind farm. The idea behind the power control concept is eliminate the violations of the steady state voltage level by buffering the power from the wind turbines in periods where the voltage limits might be violated and combine this ability with smoothing of the power output. The investigations have shown ...
1999-03-01
Energy Technology Data Exchange (ETDEWEB)
A home-made 3.1 kWh wind turbine that is promising to be the hottest new wind product to appear for home/farm users in some time, is described. The turbine is installed near a farm house in the high wind area of Mount Forest, Ontario. The turbine is hooked up to a four kilowatt Trace inverter charger which is coupled through a DC disconnect and C-60 charge controller to two sets of solar panels (seven panels of 120 W each by Solarex SX 120, and five panels by Sharp, each providing 1600 watt of solar power). The wind turbine and the solar panels, assisted by two 65-year old refurbished wind turbines, one bank of Gel Cell batteries, and an Onan 5 kW gas generator supply the electrical requirements of a seven member family in a 3400 square foot house. The new turbine is mounted on an 80-foot tower, has three eight foot Kevlar blades that ...
2004-12-31
A perspective of the Malaysian highway energy consumption and future power supply
British Library Electronic Table of Contents (United Kingdom)
In this short communication, we discuss the energy consumption trends in the Malaysian road transport sector, with a special emphasis on the energy losses due to vehicle aerodynamic drag on highways. The recent trends of energy consumption in the Malaysian road transport sector are reviewed. It is evidently shown that the aerodynamic losses represented exceed 1.2MTOE annually since 2002. A novel concept of vertical-axis wind turbine (VAWT) farms for harvesting aerodynamic energy losses on Malaysian highways is preliminarily proposed. The novel concept aims at providing a sustainable and green energy source for the lighting of the highway network in the country.
2011-01-01
Solids distribution in tall tanks
British Library Electronic Table of Contents (United Kingdom)
Abstract Uniformly distributing slurry solids in -tall- (-2:1 aspect ratio) process vessels is a significant challenge in the chemical industry. This work determined the performance of various multi-tier agitation systems in uniformly distributing a settling solid throughout water in a -tall- laboratory vessel. It used a 0.445-m ID Plexiglas tank, with a slurry height of 0.889-m, to determine how solids distribution changes with solids loading (wt.%), impeller speed, and impeller type. Some impeller types uniformly distributed the solids even before energy input exceeded 1.00-W/kg. Significantly higher energy improved solids distribution little because flow within the vessel eventually became choked.
2011-01-01
Economical evaluation of electricity generation considering externalities
International Nuclear Information System (INIS)
The economics of renewable energy are the largest barrier to renewable penetration. Nevertheless, the strong desire to reduce environmental emissions is considered a great support for renewable energy sources. In this paper, a full analysis for the cost of the kWh of electricity generated from different systems actually used in Egypt is presented. Also renewable energy systems are proposed and their costs are analyzed. The analysis considers the external cost of emissions from different generating systems. A proposed large scale PV plant of 3.3 MW, and a wind farm 11.25 MW grid connected at different sites are investigated. A life cycle cost analysis for each system was performed using the present value criterion. The comparison results showed that wind energy generation has the lowest cost, followed by a combined cycle-natural gas fired system. A photovoltaic system still uses comparatively expensive technology for ...
2002-02-01
Seismic evaluation and upgrading of critical tower pile foundations in liquefiable soils
Energy Technology Data Exchange (ETDEWEB)
An overview of BC Hydro`s review of its overhead transmission system to withstand earthquakes and its program of seismic upgrading, including the upgrading of tower pile foundations in liquefiable soils, was presented. BC Hydro`s system, geologic environment, seismic design criteria, investigations and analysis, treatment and alternatives and a case history of a seismic upgrade of a tall river crossing tower at the Pitt River in the Lower Mainland of B.C. were summarized. It was concluded that the inherent strength of towers, conductors, fittings and insulators was sufficient to withstand earthquakes. The towers most susceptible to slope and soil failure due to seismic activity were tall river crossing towers. It was suggested that soils investigations, seismicity, ground response, liquefaction and stability analyses be carried out at each site. The results of these tests would help to establish system seismic design criteria at each location. ...
1995-12-31
Environmental Research Database
DescriptionFarm-level estimates of the financial impact of regulation are important indicators of the effect that a regulation have. Such estimates should be included in RIA, particularly within the Small Firms Impact Test. This farm-level analysis can be used in the RIA to inform judgements of the affordability of the regulation proposal. It will help to identify which farm types are likely to be financially had-hit from the regulation. Farm-level cost estimates for each regulation are also required t [continued...
2007-01-23
In the current wind turbine generation system, there are substantial problems such as the maximum power of the wind turbine cannot be obtained under the fluctuating wind speed, high in cost and low in annual net electricity production (due to mismatch between a generator and a wind turbine). A new wind turbine generator optimized for the wind turbine output is presented in order to solve such problems. This wind turbine generator consists of a permanent magnet generator, a reactor and a rectifier, and uses neither a control circuit which requires standby electricity nor a PWM converter having a switching element. By selecting most appropriate combination of the permanent magnet generator having multiple windings and the reactor connected in series with each winding, the maximum output of the ...
2008-01-01
Efficient and economical utilization of wind power will require the ability to measure and ultimately predict the effects fluctuations in the incident wind will have on a wind turbine. In order to quantitatively assesss these effects, experimental techniques have been developed which allow analysis of full-scale performance of wind turbines with particular emphasis on the effects caused by turbulence in the incident wind. Examples of these techniques are presented using data from the DOE/Sandia Vertical Axis Wind Turbine (VAWT) program.
1981-01-01
Wind power in Poland; Gerangel an der Ostsee-Kueste
Energy Technology Data Exchange (ETDEWEB)
Poland intends to construct 2,000 MW of wind power systems during the next four years. This is the start of the Polish wind power industry. (orig.)
2006-08-15
UK PubMed Central (United Kingdom)
The study involved 110 randomly selected dairy farms located in the Ontario, Canada counties of Bruce, Grey, Huron, Oxford, Perth, Waterloo and Wellington. Herds were classified as "intensive" and "extensive"....Full Text Available
1986-01-01
UK PubMed Central (United Kingdom)
The purpose of this study was to assess changes in dairy herd milk production and milk composition associated with changes in Salmonella contamination of bulk milk on dairy farms in southwestern Ontario....Full Text Available
1989-04-01
Possible explosive compounds in the Savannah River Site waste tank farm facilities
Energy Technology Data Exchange (ETDEWEB)
This report will be revised upon completion of current testing investigating the radiolytic stability of additional energetic materials and the analysis of tank farm samples for volatile and semi-volatile organic compounds.
2000-04-13
UK PubMed Central (United Kingdom)
A multidisciplinary approach was used to study the effects of pollution from a marine fish farm on nitrification rates and on the community structure of ammonia-oxidizing bacteria in the underlying...Full Text Available
1999-01-01
UK PubMed Central (United Kingdom)
BackgroundAgricultural practices such as the use of irrigation during rice cultivation, the use of ponds for fish farming and the storage of water in tanks for livestock provide...Full Text Available
UK PubMed Central (United Kingdom)
AbstractA newly recognized syndrome, characterized by sudden death of farmed deer that are in good to excellent nutritional condition, with lesions of small intestinal mucosal hemorrhage...Full Text Available
2005-08-01
Farm-level risk factors for the presence of Salmonella in 89 Alberta swine-finishing barns
UK PubMed Central (United Kingdom)
This study investigated potential risk factors for the presence of Salmonella on 89 Alberta swine-finishing farms with the use of a questionnaire. Salmonella status...Full Text Available
2007-10-01
UK PubMed Central (United Kingdom)
A total of 295 ceftiofur-resistant Escherichia coli isolates were obtained from 489 cloacal samples collected at five different Belgian broiler farms with the aim to evaluate the diversity...Full Text Available
2008-04-01
Ak-Chin Indian Community Biomass Feasiiblity Study
Energy Technology Data Exchange (ETDEWEB)
Study of the conversion of chicken litter to biogas for the production of energy. There was an additional requirement that after extracting the energy from the chicken litter the nutrient value of the raw chicken litter had to be returned to the Ak-Chin Farms for use as fertilizer in a form and delivery method acceptable to the Farm.
2005-12-31
Hazardous Waste Management on the Farm
Sep 2, 2008 ... Abstract: This tutorial is intended to serve as a guide towards proper hazardous waste management. Knowing the regulations, different ...
Wind Characteristics at the Vawt Test Facility.
A limited program of field measurements was undertaken in order to define the wind characteristics of the DOE/Sandia vertical axis wind turbine test facility. Because micrometeorological conditions under which a particular wind turbine is tested may have ...
1978-01-01
VAWT Stochastic Wind Simulator.
A stochastic wind simulation for VAWTs (VSTOC) has been developed which yields turbulent wind-velocity fluctuations for rotationally sampled points. This allows three-component wind-velocity fluctuations to be simulated at specified nodal points on the wi...
1987-01-01
A study described part-time and small farmers (PT/SF) on the basis of their demographic characteristics and determined their farm management educational needs. Findings revealed that the majority of the PT/SF were males who operated farms of 50-150 acres for 11 or more years, were 35-44 years of age, and were high school graduates who principally produced crops. The four areas of farm management education needed by PT/SF were farm tax management, marketing farm products, determining farm insurance needs, and farm recordkeeping. Findings regarding a third objective--to determine the relationship between the selected demographic charcteristics and the computed farm management educational needs of PT/SF--revealed a range of negligible to substantial relationships. The moderate to substantial positive relationships existed ...
1986-12-01
Energy and greenhouse gas emissions of Australian cotton : from field to fabric
Energy Technology Data Exchange (ETDEWEB)
This paper reported on a study in which a life cycle assessment (LCA) of cotton production in Australia was conducted to evaluate energy use and greenhouse gas (GHG) emissions from tillage to export shipping. The study showed that on-farm indirect cotton-farming is the most energy consuming component, consuming nearly 32.36 GJ/ha of energy. On-farm indirect cotton-farming is the most GHG emitting component, emitting about 1.64 tonne of carbon dioxide (CO{sub 2})/ha. Energy use and the emissions by off-farm direct cotton-farming were calculated as 5.09 GJ/ha and 0.14 tonne CO{sub 2}/ha respectively. Energy consumed by off-farm indirect farming was found to be 0.036 GJ/ha or 0.002 tonne CO{sub 2}/ha. The total energy usage and greenhouse gas emissions in the Australian cotton farming system were ...
2010-07-01
Energy Technology Data Exchange (ETDEWEB)
Wind Powering America program launched the New England Wind Forum (NEWF) in 2005 to provide a single comprehensive source of up-to-date, Web-based information on a broad array of wind energy issues pertaining to New England. The NEWF newsletter provides New England stakeholders with updates on wind energy development in the region. In addition to regional updates, Issue #5 offers an interview with Angus King, former governor of Maine and co-founder of Independence Wind.
2010-01-01
Mean wind field in the urban atmospheric boundary layer by sodar data
Energy Technology Data Exchange (ETDEWEB)
Two-year uninterrupted sodar measurements of vertical profiles of wind speed and direction in the height range 40 to 250-500 m were carried out in two points of Moscow megalopolis. Seasonal and diurnal courses of mean speed profiles, wind speed distributions, wind roses and occurrence of strong and weak wind speed events are shown. Influence of urban heat island and orography on wind field is discussed.
2008-05-01
Energy Technology Data Exchange (ETDEWEB)
The assets that Citizen Potawatomi Nation holds were evaluated to help define the strengths and weaknesses to be used in pursuing economic prosperity. With this baseline assessment, a Planning Team will create a vision for the tribe to integrate into long-term energy and business strategies. Identification of energy efficiency devices, systems and technologies was made, and an estimation of cost benefits of the more promising ideas is submitted for possible inclusion into the final energy plan. Multiple energy resources and sources were identified and their attributes were assessed to determine the appropriateness of each. Methods of saving energy were evaluated and reported on and potential revenue-generating sources that specifically fit the tribe were identified and reported. A primary goal is to create long-term energy strategies to explore development of tribal utility options and analyze renewable energy and energy efficiency options. Associated goals are to consider exploring ...
2004-12-01
Secondary stresses on transmission tower structures
Energy Technology Data Exchange (ETDEWEB)
The power industry is moving toward the use of high-voltage transmission lines on tall, flexible towers. These towers are designed for heavier loadings than were previous towers, but the secondary effects of tower displacement tend to be ignored in the present day tower analysis. This paper examines the secondary effects from the large displacement of flexible towers, reviews the secondary stresses arising from joint rigidity and member continuity, and examines the reliability of tower strength predicted by the ASCE design guidelines. More realistic tower test acceptance criteria and a more reliable tower design methodology are suggested.
1984-06-01
Energy Technology Data Exchange (ETDEWEB)
This work develops and demonstrates a laboratory-scale high temperature natural gas furnace that can operate with/without oxygen enrichment to significantly improve energy efficiency and reduce emissions. The laboratory-scale is 5ft in diameter & 8ft tall. This furnace was constructed and tested. This report demonstrates the efficiency and pollutant prevention capabilities of this test furnace. The project also developed optical detection technology to control the furnace output.
2007-02-16
Energy Technology Data Exchange (ETDEWEB)
A complete analysis is performed to simulate biomass production incorporated into a realistic whole farm situation, including or replacing a typical crop mix. Representative farms are constructed to accommodate such simulation. Four management systems are simulated for each firm, with each simulation depicting a different crop mix and/or use of different farming technologies and production methods. The first simulation was a base farm plan in which the operator would maintain the historical crop mix for the area, participate in all price support programs, and not participate in either a conservative reserve or a biomass production program. In the second simulation, the operator would again maintain the historical crop mix, would not participate in a conservation reserve or biomass production program, and would be ineligible to participate in any price support system. The third simulation introduced the ...
1992-01-01
Development of a farm-firm modelling system for evaluation of herbaceous energy crops
Energy Technology Data Exchange (ETDEWEB)
A complete analysis is performed to simulate biomass production incorporated into a realistic whole farm situation, including or replacing a typical crop mix. Representative farms are constructed to accommodate such simulation. Four management systems are simulated for each firm, with each simulation depicting a different crop mix and/or use of different farming technologies and production methods. The first simulation was a base farm plan in which the operator would maintain the historical crop mix for the area, participate in all price support programs, and not participate in either a conservative reserve or a biomass production program. In the second simulation, the operator would again maintain the historical crop mix, would not participate in a conservation reserve or biomass production program, and would be ineligible to participate in any price support system. The third simulation introduced the ...
1992-01-01
The Earth in energy troubles; La Planete en mal d'energie
Energy Technology Data Exchange (ETDEWEB)
This document gathers the available presentations (articles and transparencies) given at this annual meeting, the 2007 topic of which was the technological, geopolitical, economical, environmental, societal and development stakes of energy. 1 - technological stakes - which energies for the future: new energies, illusion or solution of the future; the Lorraine region, an energy land: strategies and stakes for a sustainable development; from China to Brazil: understanding the nuclear energy revival; hydroelectric power: renewable and sustainable energy; renewable energies and environment protection: the contribution of biofuels; wind power in Germany between success and contestation; 2 - geopolitical stakes - energy levier of power: the Gulf of Guinea hydrocarbons: between development and geopolitics; the complex evaluation of resources and reserves between technology, market and geopolitics; the new Bakou-Tbilissi-Ceyhan pipeline: what impacts for Turkey and the ...
2007-07-01
Heinz Dahl: presenting offshore wind energy for Australia
...Heinz Dahl: presenting offshore wind energy for Australia NexTgen Wind. Next month, Heinz L Dahl will speak about offshore wind energy and its prospects for Australia. Skip to the navigation. Skip to the content. Events Models Movements Opinion Policies Research SCRT Videos Seeking ... August guest speaker: Heinz Dahl, managing director, NexTgen Wind. Next month, Heinz L Dahl will speak about offshore wind energy and its prospects for Australia. Heinz is the managing director of NexTgen Wind, a leading edge company that is focused on the cost ...
Energy Technology Data Exchange (ETDEWEB)
A wind turbine is provided which consists of novel vanes horizontally oriented about a rotating hub connected to a vertical shaft. The vanes are free to pivot about two horizontal hinges such that two vanes connected to each other open when wind force is applied, and close when there is little or no wind force such that there is a minimal amount of resistance to the travel of the vanes when the vanes are against the wind.
1983-03-22
Wind or water driven wheel and bird scarer
Energy Technology Data Exchange (ETDEWEB)
The wind unit working wheel has 4 radial rectangular frames arranged in two vertical planes which are perpendicular to each other. In the planes limited by the frames, on loop hinges with limiting supports, there are flat blades. When the working wheel rotates under the influence of wind pressure, the blades automatically occupy a vertical or horizontal (wind vane) position depending on the direction of blade motion and the direction of wind velocity.
1984-01-04
Designed primarily for Missouri vocational agricultural instructors participating in the Farm Business Management Analysis Program, this instructor's guide, consisting of 10 lessons, deals with adjusting a farm business to increase profits. The following topics are covered in the individual lessons: law and the farm family, planning income tax management, closing the record book and planning cash flow, evaluating family living expenses, determining the most profitable livestock enterprise, determining the most profitable cropping system, planning the farm marketing program, adjusting capital investments to increase net profit, planning for efficient labor use, and controlling costs. Included in each section are suggestions for a review of previous materials covered, an objective, motivational techniques, key points to be addressed in the lesson, information to be introduced during the lesson, ...
1982-06-01
Use of multipurpose trees in hill farming systems in western Nepal
Energy Technology Data Exchange (ETDEWEB)
A study of two villages identified 55 woody perennial species that are maintained in contour strips across slopes and around fields in a subsistence farming system. These trees and shrubs produced fodder and firewood and reduced erosion hazards, allowing crop production on very steep slopes where it would otherwise be very difficult. Data on basic farm management, production of crops, etc. are discussed. The performance of the system is assessed and its strengths and weaknesses highlighted. It is suggested that several locally available medicinal plants could be incorporated into the system.
1984-01-01
The role of contagious disease in udder health
UK PubMed Central (United Kingdom)
Contagious diseases are a threat to animal health and productivity, both nationally and at the farm level. This makes implementation of biosecurity measures to prevent their introduction and...Full Text Available
2009-10-01
Evaluation of enteric methane prediction equations for dairy cows used in whole farm models
British Library Electronic Table of Contents (United Kingdom)
Abstract The importance of evaluating greenhouse gas (GHG) emissions from dairy cows within the whole farm setting is being realized as more important than evaluating these emissions in isolation. Current whole farm models aimed at evaluating GHG emissions make use of simple regression equations to predict enteric methane (CH4) production. The objective of the current paper is to evaluate the performance of nine CH4 prediction equations that are currently being used in whole farm GHG models. Data used to evaluate the prediction equations came from a collection of individual (IND) and treatment averaged (TRT) data. Equations were compared based on mean square prediction error (MSPE) and concordance correlation coefficient (CCC) analysis. In general, predictions were poor, with root MSPE (as...
2010-01-01
Diagnostics of Radionuclides Effects Results
International Science & Technology Center (ISTC)
Development of New Methods and Means of Assessing of Consequences of Radionuclide and Heavy Metal Salt Effect, Criteria of Forecasting Physiological State and Productivity of the Farm Animals under Conditions of Ecological Pollution of Environment
Government policies that encourage exploitation--in particular excessive logging and clearing for ranches and farms--are largely to blame for the accelerating destruction of tropical forests. This paper surveys the problem in detail and briefly recommends potential solutions.
1990-04-01
CFSAN - Questions and Answers on FDA's Import Alert on Farm-Raised ...
... Program on nitrofurans. Nitrofurazone (TR-337 published in June 1988) and Nitrofurantoin (TR-341 published in Sept 1989). Both of ...
Visual impact evaluation of a wind park in a Greek island
Energy Technology Data Exchange (ETDEWEB)
The visual impact of wind turbines is one of the main factors affecting public acceptance of wind parks. This paper evaluates the visual impact of a wind park in Chania, Crete, using the Spanish method of evaluation. The outcomes are combined with the psychometric testing of the residents by the use of questionnaires and with the values of the Spanish method about various scenarios concerning the size of the wind park (double, half, one wind turbine). The results of the study prove that the quantification of the potential visual impact could minimize this, apparently, main reason that affects public acceptance. (author)
2009-04-15
Wind power in China-Opportunity goes with challenge
British Library Electronic Table of Contents (United Kingdom)
Climate change and limited primary energy resources require indigenous renewable electricity generation options to change the current coal-dominated power source matrix in China. The wind power is such a solution for the above challenges, and it still has large space for improvement in China. In this paper several critical factors related to Chinese wind power were studied in details, including the wind resources, the wind turbine industry and the policies from the Chinese government. Based on the study, the perspective of wind power in China was discussed. With outstanding advantages, the offshore wind power has a bright future in China, so its main characteristics are discussed. Based on the discussions, suggestions were given to improve the development of Chinese wind power, and the gov...
2010-01-01
Wind power in China - Opportunity goes with challenge
Energy Technology Data Exchange (ETDEWEB)
Climate change and limited primary energy resources require indigenous renewable electricity generation options to change the current coal-dominated power source matrix in China. The wind power is such a solution for the above challenges, and it still has large space for improvement in China. In this paper several critical factors related to Chinese wind power were studied in details, including the wind resources, the wind turbine industry and the policies from the Chinese government. Based on the study, the perspective of wind power in China was discussed. With outstanding advantages, the offshore wind power has a bright future in China, so its main characteristics are discussed. Based on the discussions, suggestions were given to improve the development of Chinese wind power, and the government's further measures are also ...
2010-10-15
Distinct sensory representations of wind and near-field sound in the Drosophila brain
UK PubMed Central (United Kingdom)
Behavioral responses to wind are thought to play a critical role in controlling the dispersal and population genetics of wild Drosophila species1,Full Text Available
2009-03-12
Cost effective use of liquid nitrogen in cryogenic wind tunnels
A method of reliquefying from 12 to 19% of the nitrogen exhaust gas from a cryogenic wind tunnel has
1987-01-01
Simple calculation of daily photosynthesis by means of five photosynthesis-light equations
Energy Technology Data Exchange (ETDEWEB)
The performance of five well-known photosynthesis-light equations is compared by presenting a wide range of solutions in the form of dimensionless nomographs for the case where photosynthetically available radiation (PAR) reduces exponentially down the water column and is distributed sinusoidally through the photoperiod. These provide a simple means of calculating daily photosynthesis at any depth (e.g. at a benthic layer), or through a water column, avoiding the need to perform complex integrations. An examination is made of the accuracy of common approximate methods for calculating daily photosynthesis, assuming constant PAR. For optically deep water a modification is proposed to Talling's planimetric solution, to enable daily photosynthesis to be calculated more accurately, yet simply, over the whole range of possible PAR values. The errors induced by approximating the daily PAR distribution as a half-sinusoid are also reported. 13 refs., 9 figs., 5 ...
1992-12-01
Seismic evaluation and upgrading of critical tower pile foundations in liquefiable soils
Energy Technology Data Exchange (ETDEWEB)
BC Hydro has been assessing and upgrading its facilities and implementing response alternatives to potential damage resulting from a major earthquake. This paper reviews the utility`s seismic evaluation of its overhead transmission system, focusing on the Lower Mainland area where most of the tall critical river-crossing towers are located. The paper gives an overview of the geologic environment of the Lower Mainland and outlines the criteria used for assessing existing structures for their ability to withstand design seismic loads. It then describes the investigation and analysis methods used in the assessment, including geotechnical field tests, ground response analysis, determination of soil liquefaction potential, and dynamic analysis of structures and piles. Options for seismic upgrades are discussed and illustrated by the case of the Pitt River crossing, where tower foundations were reinforced with steel pipe piles.
1995-12-31
Energy Technology Data Exchange (ETDEWEB)
Wind power is an increasingly significant renewable energy resource, producing no environmentally damaging C0{sub 2} emissions. The efficient production of electricity by wind turbines relies on aerodynamics: aerodynamics of wind turbines provides the fundamental solutions to efficient wind turbine design. Following a historical introduction, Part 1 of Aerodynamics of Wind Turbines is concerned with basic rotor aerodynamics, while Part 2 deals with structural aspects of the wind turbine and calculation of the loads on it. Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element Momentum method is also covered, as are eigenmodes and ...
2000-06-15
Energy Technology Data Exchange (ETDEWEB)
Wind power is an increasingly significant renewable energy resource, producing no environmentally damaging CO2 emissions. The efficient production of electricity by wind turbines relies on aerodynamics. Aerodynamics of Wind Turbines provides the fundamental solutions to efficient wind turbine design. Following a historical introduction, Part 1 of Aerodynamics of Wind Turbines is concerned with basic rotor aerodynamics, while Part 2 deals with structural aspects of the wind turbine and calculation of the loads on it. Topics covered include increasing mass flow through the turbine, performance at low and high wind speeds, assessment of the extreme conditions under which the turbine will perform and the theory for calculating the lifetime of the turbine. The classical Blade Element Momentum method is also covered, as are eigenmodes and the ...
2001-01-01
Inventory of Tank Farm equipment stored or abandoned aboveground
Energy Technology Data Exchange (ETDEWEB)
This document provides an inventory of Tank Farm equipment stored or abandoned aboveground and potentially subject to regulation. This inventory was conducted in part to ensure that Westinghouse Hanford Company (WHC) does not violate dangerous waste laws concerning storage of potentially contaminated equipment/debris that has been in contact with dangerous waste. The report identifies areas inventoried and provides photographs of equipment.
1994-10-12
Energy Technology Data Exchange (ETDEWEB)
The High-Level Waste Storage Tank Farms/242-A Evaporator Standards/Requirements Document (S/RID) is contained in multiple volumes. This document (Volume 2) presents the standards and requirements for the following sections: Quality Assurance, Training and Qualification, Emergency Planning and Preparedness, and Construction.
1994-04-01
Environmental Research Database
DescriptionFollowing publication of the Curry report, DEFRA have made a commitment to establish a number of pilot projects supporting a network of demonstration and development farms. These 'farms' are intended to support the process of technology transfer by giving free access to information on the practical application of new, emerging and best practice technologies. Protected Horticulture has been identified as a sub-sector requiring the establishment of one of these projects. One of the major pressures [continued...
2005-01-31
Energy Technology Data Exchange (ETDEWEB)
The study concerns 1984-1991. The wind park consists of 18 three-bladed 300 kW horizontal axis wind turbines of 35 meters height, and a rotor diameter of 30 meters, seven meteorological towers, and three cluster and control buildings. Aspects studied included disturbance of breeding, resting or feeding, and migrating birds, behavior of birds approaching the wind turbines during the day and night, and bird victims due to collision with the wind turbines and the meteorological towers. The flight behavior of birds approaching the wind park system during daylight is also dealt with. For at least a fifth of the observations it was noted whether the birds passing within 100 meters distance of a turbine showed a reaction or not. The proportion of the reactions was related to the wind park in operation or not in operation, and to the distance between the ...
1992-01-01
Evolution of the chromospheres and winds of low- and intermediate-mass giant stars
International Nuclear Information System (INIS)
Results are presented of an empirical analysis of the global thermodynamical requirements of the winds in the outer atmospheres of a representative sample of red giant stars of low- and intermediate-mass range. Results indicate that the mass-loss rates in these stars are not strongly dependent on the actual physical processes driving the winds. It is suggested that nonlinear processes act to regulate wind energy fluxes. Possible mechanisms responsible for the chromospheric heating and the mass loss in the low- and intermediate-mass giant stars are discussed. 151 refs.
Wind tunnel and numerical study of a small vertical axis wind turbine
British Library Electronic Table of Contents (United Kingdom)
This paper presents a combined experimental and computational study into the aerodynamics and performance of a small scale vertical axis wind turbine (VAWT). Wind tunnel tests were carried out to ascertain overall performance of the turbine and two- and three-dimensional unsteady computational fluid dynamics (CFD) models were generated to help understand the aerodynamics of this performance. Wind tunnel performance results are presented for cases of different wind velocity, tip-speed ratio and solidity as well as rotor blade surface finish. It is shown experimentally that the surface roughness on the turbine rotor blades has a significant effect on performance. Below a critical wind speed (Reynolds number of 30,000) the performance of the turbine is degraded by a smooth rotor surface finis...
2010-01-01
Renewable Energy in Danish Municipalities - an Evaluation of The Planning Framework for Wind Power
DEFF Research Database (Denmark)
Wind power is a maturing technology that in a number of countries is likely to contribute a major share to fully renewable energy systems. Denmark has a comparably long history of wind power development and is planning to continue expanding the existing capacity. If a large-scale penetration of wind power is to be achieved, an integrated framework is needed that can respond to the associated challenges. This paper argues for adopting an integrated macro perspective when evaluating and building frameworks to support wind power development. This macro perspective is applied to the case of Denmark, and more specifically to concrete wind power projects in the region of Northern Jutland. The results suggest although certain elements in the legislation have been improved, the feasibility of wind power projects cannot be guaranteed, and there is a tendency to exclude ...
2009-01-01
Prospects of wind energy in Bangladesh
Energy Technology Data Exchange (ETDEWEB)
Wind speed has been measured in Patenga, Cox`s Bazar, Kuakata, Moheshkhali, and Noakhali by the computerized anemometers. The wind computers have been installed at 20 meters height. According to this study annual average wind speeds in the coastal regions of Bangladesh are greater than 6.5 m/s at the height of 20 meters. It has been observed that during day times (8 a.m. to 7 p.m.) wind speeds are about 30 to 40% higher than the average values. The value of the power exponent {alpha} has been determined in the above sites and it is 0.139. So, at 40 meters height the annual average wind speed is about 7.15 m/s. So, wind speeds in the coastal regions of Bangladesh are suitable for both water pumping and electricity generation. Details are given in this paper with graphical and analytical representations. (author)
1996-09-01
Several observational studies suggest that solar wind dynamic pressure fluctuations can drive magnetospheric ultra-low frequency (ULF) waves on the dayside. To investigate this causal relationship, we present results from Lyon-Fedder-Mobarry (LFM) global, three-dimensional magnetohydrodynamic (MHD) simulations of the solar wind-magnetosphere interaction. These simulations are driven with synthetic solar wind input conditions, where idealized ULF dynamic pressure fluctuations are embedded in the upstream solar wind. In three of the simulations, a monochromatic, sinusoidal ULF oscillation is introduced into the solar wind dynamic pressure time series. In the fourth simulation, a continuum of ULF fluctuations over the 0-50 mHz frequency band is introduced into the solar wind dynamic pressure time series. In this numerical experiment, the idealized solar ...
2010-01-01
Development of a methodology to assess the climate evolution and its impacts on wind energy
International Nuclear Information System (INIS)
Maps of wind resources were used to develop a method of evaluating climatic changes and their potential impacts on wind energy resources. Global IPCC climate change scenarios were used to predict climatic conditions for the future, while past wind resource availability was simulated and validated using NCEP and NCAR reanalysis data as well as observed meteorological data from Environment Canada. The simulations were used to compare each 5-year period with a 50-year reference period. Regional scale climate change impacts were evaluated using a statistical dynamic down-scaling method. Advanced meteorological models were used to predict wind flow patterns across specific landscapes. The evolution of past wind resource availability was then simulated. Five-year wind resource simulations for a 50-year period were simulated at 25 km"2 wind speeds ...
2010-11-01
The AMPTE program's contribution to studies of the solar wind-magnetosphere-ionosphere interaction
Energy Technology Data Exchange (ETDEWEB)
The Active Magnetospheric Particle Tracer Explorers (AMPTE) program provided important information on the behavior of clouds of plasma artificially injected into the solar wind and the earth's magnetosphere. Now that the releases are over, data from the satellites are being analyzed to investigate the processes by which the ambient solar wind mass, momentum, and energy are transferred to the magnetosphere. Work in progress at APL indicates that the solar wind is much more inhomogeneous than previously believed, that the solar wind constantly buffets the magnetosphere, and that ground observers may remotely sense these interactions as geomagnetic pulsations. 8 refs.
1990-12-01
SUSTAINABLE H/C SYSTEMS FOR CHICKEN FARMS IN SYRIA
Energy Technology Data Exchange (ETDEWEB)
Space heating/cooling systems account for approximately 30% of the global energy consumption. Such systems contribute to global warming by emitting 0.39.1011 MWh of heat and 2.9.1010 tons of CO{sub 2}. There is a general understanding that the way to reduce global warming is a more efficient use of energy and increased use of renewable energy in all fields of the society. The poultry industry in the Mid East is an important business. There are e.g. 13000 chicken farms in Syria producing 172,000 ton of meat. This industry employs directly almost 150,000 people. The total investment in chicken farming is 130 BSP. Even though, the annual mean temperature in Syria is {approx}15-18 C the winter temperatures are close to freezing for two months. Since the chickens need a temperature of 21-35 C, depending on age, approximately 168.103 tons of coal (1170 GWh) is consumed for heating these plants. The chicken farms have no cooling ...
2008-09-30
Farm & Ranch Business Management. Second Edition.
This practical guide for the agribusiness manager (the farmer, rancher, and other agribusiness people who work with agricultural commodities, supplies, and services) gives a basic understanding of modern management practices. It provides guidelines that can help them make practical business decisions. Chapter 1 is an introduction that highlights farm management efficiency, decision making, and goals and objectives. The following 11 chapters discuss recordkeeping (importance and purposes of keeping records, types of systems, record book components), financial analysis (cash flow, net worth, income statements and their ratios; whole farm and enterprise analysis; relationships of various analyses), budget analysis (introduction to types and uses of budgets, how to use and analyze a partial budget, enterprise budget and whole farm budget, production principles, cost components), cash flow analysis (projections and analysis, ...
1986-12-01
Evaluating the performance of wind turbines in selected locations in Oyo state, Nigeria
British Library Electronic Table of Contents (United Kingdom)
The wind speed distribution and wind energy potential are investigated in three selected locations in Oyo state using wind speed data that span between 12 and 20 years measured at 10 m height. In addition, the performance of selected small to medium size wind turbines in these sites were examined. The annual energy output and capacity factor for these turbines were determined. It was found that the monthly mean wind speeds in Oyo state ranges from 2.85 m/s to 5.20 m/s. While the monthly mean power density varies between 27.08 W/m2 and 164.48 W/m2, while the annual mean power density is in the range of 67.28 W/m2 and 106.60 W/m2. Based on annual energy output, wind turbines with cut-in wind speed of about 2.5 m/s and moderate rated wind speeds will be best suited for all the sites.
2011-01-01
Effect of site wind properties on wind-electric conversion costs
Energy Technology Data Exchange (ETDEWEB)
The unit cost of energy production of wind generators is examined by means of a model of the turbine power curve and the Weibull model of wind probability function, by applying the usual economic equations. The analysis is carried out in terms of dimensionless variables whose range of variability is defined by examining the data of 80 modern commercial wind turbines; likewise, the economic parameters are based on the present state of costs. The unit cost decreases asymptotically when alpha (ratio between mean wind speed and cut-in speed) - increases and shows a lower limit of 2 to 5 Ecent/kWh. This cost depends both on the value of the machine parameter {phi} (ratio between nominal and cut-in speed) and on the basic prices. The effect of the Weibull shape parameter kappa is different according to the values of {alpha} and {phi}: with low {alpha} and high {phi} the unit cost increases along with {kappa} ...
2004-12-01
British Library Electronic Table of Contents (United Kingdom)
A web-based decision support tool, zone mapping application for precision farming (ZoneMAP, External Reference Not Shown ), has been developed to automatically determine the optimal number of management zones and delineate them using satellite imagery and field data provided by users. Application rates, such as of fertilizer, can be prescribed for each zone and downloaded in a variety of formats to ensure compatibility with GPS-enabled farming equipment. ZoneMAP is linked to Digital Northern Great Plains, a web-based application which hosts an archive of satellite imagery, as well as high resolution imagery from airborne sensors. Management zones created by ZoneMAP mapped natural variation of the soil organic matter and other nutrients relatively well and were consistent with zone maps cre...
2010-01-01
Study on regional production and economy of cobia Rachycentron canadum commercial cage culture
British Library Electronic Table of Contents (United Kingdom)
In recent years, cobia has become an emerging farmed species in Asia due to its quick growth and high economic value. This study collects biological and economic data affecting the economic performance of cobia farming in three countries, namely Taiwan, China, and Vietnam. The data are collected by questionnaire sampling and analyzed by multivariate statistical analysis in order to compare the key factors affecting the production and economy of cobia farming in these three countries. The results show that Taiwan, China, and Vietnam have significant differences in input intensities and profitability. China has the highest input intensity (3372.42?TWD/m3), as its high stocking density increases feed input. Taiwan has the highest unit input cost (103.44?TWD/kg), as the high quality of the pro...
2011-01-01
Importance of health and environment as quality traits in the buying decision of organic products
British Library Electronic Table of Contents (United Kingdom)
This paper aims to explore consumer preference for fresh vegetables labelled as organic in combination with health and environment related quality traits. The study decomposes organic farming into its main quality aspects and measures consumers' preference structure for organic, in general, and for specific organic quality traits in particular. By means of stated choice preference modelling, the following hypotheses are tested: consumers prefer health over environment related quality traits; the organic label plays a significant role in consumers' choice for organic products; organic farming is perceived as healthier and more environmentally friendly than conventional farming; purchase intention is mainly driven by health related quality traits; both health and environmental concerns influ...
2009-01-01
Farm Business Management. Volume I. Vocational Agriculture Education.
This curriculum guide provides a basic core of instruction for the first year of a three-year adult program in farm business management. It contains 12 units of instruction. Each unit consists of seven basic components: performance objectives, teacher activities, information sheets (content essential for meeting the cognitive objectives), assignment sheets (application of knowledges that are prerequisites to skill development), supplements and transparency masters, tests, and test and assignment sheet answers. Depending on the specific objectives, supplements, transparency masters, assignment sheets, and job sheets may or may not be included. The 12 units cover orientation, recordkeeping, inventory and net worth statement, depreciation, enterprise accounting and supplemental records, enterprise budgets, cash-flow planning, farm credit, partial budgeting, marketing, income tax management, and year-end closing of records. (YLB)
1983-12-01
Cats and goat whey associated with Toxoplasma gondii infection in pigs.
In organic livestock production systems, farm-management factors are thought to play an important role in the on-farm prevalence of Toxoplasma gondii. Serological results and the results of an HACCP analysis were combined to determine important risk factors for the prevalence of this protozoan parasite. Mathematical analysis demonstrated that feeding goat whey to pigs and the presence of a high number of cats were positively correlated to T. gondii seroprevalence in pigs. Not covering roughage and the farmers' assumption that pigs can come into contact with cat feces also showed a positive relationship. In order to decrease the risk of T. gondii infecting their pigs, farmers should limit the access and number of cats on their farms and refrain from feeding goat whey to their pigs. PMID:16989566
2006-01-01
Assessing farming eco-efficiency: A Data Envelopment Analysis approach
British Library Electronic Table of Contents (United Kingdom)
This paper assesses farming eco-efficiency using Data Envelopment Analysis (DEA) techniques. Eco-efficiency scores at both farm and environmental pressure-specific levels are computed for a sample of Spanish farmers operating in the rain-fed agricultural system of Campos County. The determinants of eco-efficiency are then studied using truncated regression and bootstrapping techniques. We contribute to previous literature in this field of research by including information on slacks in the assessment of the potential environmental pressure reductions in a DEA framework. Our results reveal that farmers are quite eco-inefficient, with very few differences emerging among specific environmental pressures. Moreover, eco-inefficiency is closely related to technical inefficiencies in the managemen...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
Indoor air exposures to gaseous contaminants originating in soil can cause large human health risks. To predict and control these exposures, the mechanisms that affect vapor transport in near-surface soils need to be understood. In particular, radon exposure is a concern since average indoor radon concentrations lead to much higher risks than are generally accepted for exposure to other environmental contaminants. This dissertation examines an important component of the indoor radon problem: the impacts of wind on soil-gas and radon transport and entry into buildings. The research includes experimental and modeling studies of wind`s interactions with a building`s superstructure and the resulting soil-gas and radon flows in the surrounding soil. In addition to exploring the effects of steady winds, a novel modeling technique is developed to examine the impacts of fluctuating winds on soil-gas and radon ...
1996-05-01
Wind turbine fault diagnosis based on Morlet wavelet transformation and Wigner-Ville distribution
British Library Electronic Table of Contents (United Kingdom)
Based on the Morlet wavelet transformation and Wigner-Ville distribution (WVD), we present a wind turbine fault diagnosis method in this paper. Wind turbine can be damaged by moisture absorption, fatigue, wind gusts or lightening strikes. Due to this reason, there is an increasing need to monitor the health of these structures. Vibration analysis is the best-known technology applied in wind turbine condition monitoring, in which the time-frequency analysis techniques such as Wigner-Ville distribution (WVD) are widely used. Theoretically WVD has an infinite resolution in time-frequency domain. For early wind turbine fault signals, however, there are two main difficulties in WVD analysis. One is strong noise signals in the background and the other is cross terms in WVD itself. In this paper,...
2010-01-01
VAWT stochastic wind simulator
Energy Technology Data Exchange (ETDEWEB)
A stochastic wind simulation for VAWTs (VSTOC) has been developed which yields turbulent wind-velocity fluctuations for rotationally sampled points. This allows three-component wind-velocity fluctuations to be simulated at specified nodal points on the wind-turbine rotor. A first-order convection scheme is used which accounts for the decrease in streamwise velocity as the flow passes through the wind-turbine rotor. The VSTOC simulation is independent of the particular analytical technique used to predict the aerodynamic and performance characteristics of the turbine. The VSTOC subroutine may be used simply as a subroutine in a particular VAWT prediction code or it may be used as a subroutine in an independent processor. The independent processor is used to interact with a version of the VAWT prediction code which is segmented into deterministic and stochastic modules. Using VSTOC in ...
1987-04-01
Three-dimensional elastic lidar winds
Energy Technology Data Exchange (ETDEWEB)
Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three- dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain following ...
1996-07-01
PIV measurements of flows around the wind turbines with a flanged-diffuser shroud
British Library Electronic Table of Contents (United Kingdom)
The wind turbines with a flanged-diffuser shroud-so called ?wind lens turbine??-are developed as one of high performance wind turbines by Ohya et al. In order to investigate the flow characteristics and flow acceleration, the paper presents the flow velocity measurements of a long-type and a compact-type wind turbines with a flanged-diffuser shroud by particle image velocimetry. In the case of the long type wind turbine, the velocity vectors of the inner flow field of the diffuser for turbine blades rotating and no blades rotating are presented at Reynolds number, 0.9?105. Furthermore the flow fields between with and without rotating are compared. Through the PIV measurement results, one can realize that the turbine blades rotating affects as suppress the disturbance and the flow separatio...
2008-01-01
Watchdog Calls on USDA to Boost Transparency in Organic Governance
...qualified and who were under consideration at the time, USDA Secretary Tom Vilsack chose an animal husbandry specialist employed by one of the largest organic livestock product marketers in the country. While this appointee had grown up on a conventional farm, her immediate occupation is not that of ...
Vibrios Associated with Litopenaeus vannamei Larvae, Postlarvae, Broodstock, and Hatchery Probionts
UK PubMed Central (United Kingdom)
Several bacteriological surveys were performed from 1994 to 1996 at different Litopenaeus vannamei hatcheries (in Ecuador) and shrimp farms (in Mexico). Samples were taken from routine...Full Text Available
1999-06-01
Transmission of Salmonella mbandaka to cattle from contaminated feed.
UK PubMed Central (United Kingdom)
Salmonella mbandaka was isolated from cattle on three dairy farms. The duration of infection was less than four weeks and none of the animals became clinically ill. The animals had all consumed a diet...Full Text Available
1982-04-01
UK PubMed Central (United Kingdom)
Commercial feed rations containing sulfamethazine at the level of 110 ppm were fed for a period of 65 days to market pigs in a study simulating normal farm practices. The levels of sulfamethazine at...Full Text Available
1980-07-01
UK PubMed Central (United Kingdom)
The introduction and survival of zoonotic bacterial pathogens in poultry farming have been linked to bacterial association with free-living protozoa. To date, however, no information is available on...Full Text Available
2011-03-01
Outbreak of acute colitis on a horse farm associated with tetracycline-contaminated sweet feed.
UK PubMed Central (United Kingdom)
Exposure of a group of horses to tetracycline-contaminated feed resulted in acute colitis and subsequent death in one horse and milder diarrhea in 3 others. The most severely affected animal demonstrated...Full Text Available
1999-10-01
Organic farming in the Nordic countries--animal health and production.
Organic farming (or ecological agriculture) is of growing importance in the agricultural sector worldwide. In the Nordic countries, 1-10% of the arable land was in organic production in 1999. Organic farming can be seen as an approach to agriculture where the aim is to create integrated, humane, environmentally and economically sustainable agricultural production systems. Principles like nutrient recycling, prevention rather than treatment and the precautionary principle are included in aims and standards. Animal welfare is another hallmark of organic livestock production but despite this, several studies have indicated severe health problems e.g. in organic poultry production in Denmark. Also the quality of animal food products in relation to human health, particularly the risk of zoonotic infections, has been debated. For these reasons there is a need for improvement of production methods and animal health status. Vets play an important role ...
2001-01-01
...Agriculture Analysis of food supply chains and linkages in relation to quality and safety assurances Dept of Primary Industries, Australia Impact of food chain quality assurance requirements on farmer adoption and competitiveness UK Research Councils Review of environmental certification through farm assurance followed by industry developmental workshop Agriculture & ...
...this pathway study the following two focus modules (in addition to the six core modules) and carry out a research investigation within this theme: Agricultural Production Systems Considers the type of farming systems that have evolved globally in relation to the prevailing agro-climatic zones, the influences of economic factors ...
Mycotoxins in fungal contaminated samples of animal feed from western Canada, 1982-1994.
UK PubMed Central (United Kingdom)
Feed samples from 94 cases involving fungal contamination and suspected mycotoxicosis of farm animals in western Canada were examined during 1982-1994 to assess the incidence of mycotoxins. Samples...Full Text Available
1997-01-01
Incidence and Diversity of Potentially Highly Heat-Resistant Spores Isolated at Dairy Farms
UK PubMed Central (United Kingdom)
The presence of highly heat-resistant spores of Bacillus sporothermodurans in ultrahigh-temperature or sterilized consumer milk has emerged as an important item in the dairy industry....Full Text Available
2005-03-01
UK PubMed Central (United Kingdom)
Background and AimsSulfonylurea (SU) herbicides are used extensively in cereal–livestock farming zones as effective and cheap herbicides with useful levels of residual activity....Full Text Available
2008-05-01
UK PubMed Central (United Kingdom)
In response to reports that the contamination of food can occur during the on-farm primary phase of food production, we report data that describes a possible cost-effective intervention measure. The...Full Text Available
2004-09-01
UK PubMed Central (United Kingdom)
BackgroundTrypanosomosis is a major impediment to livestock farming in sub-Saharan Africa and limits the full potential of agricultural development in the 36 countries where it is...Full Text Available
UK PubMed Central (United Kingdom)
BackgroundA microsporidian was previously reported to infect the crustacean parasite, Lepeophtheirus salmonis (Krøyer, 1837) (Copepoda, Caligidae), on farmed...Full Text Available
UK PubMed Central (United Kingdom)
Johne disease, caused by Mycobacterium avium, subspecies paratuberculosis (MAP) is becoming increasingly widespread on dairy farms worldwide, due in part, to the absence...Full Text Available
2010-05-01
UK PubMed Central (United Kingdom)
BackgroundWhite spot syndrome (WSS) is a viral disease that affects most of the commercially important shrimps and causes serious economic losses to the shrimp farming industry worldwide....Full Text Available
UK PubMed Central (United Kingdom)
Detecting plant health conditions plays a key role in farm pest management and crop protection. In this study, measurement of hyperspectral leaf reflectance in rice crop (Oryzasativa...Full Text Available
2007-10-01
UK PubMed Central (United Kingdom)
Enzootic Glassers's disease was investigated to study the epidemiology of the disease strains on a farm where it presented a problem. Restriction endonuclease fingerprinting (REF) analysis technique...Full Text Available
1993-08-01
An initial comparative map of copy number variations in the goat (Capra hircus) genome
UK PubMed Central (United Kingdom)
BackgroundThe goat (Capra hircus) represents one of the most important farm animal species. It is reared in all continents with an estimated world population of...Full Text Available
A 40 GByte/s read-out system for GEM
Energy Technology Data Exchange (ETDEWEB)
The preliminary design of the read-out system for the GEM (Gammas, Electrons, Muons) detector at the Superconducting Super Collider is presented. The system reads all digitized data from the detector data sources at a Level 1 trigger rate of up to 100 kHz. A total read-out bandwidth of 40 GBytes/s is available. Data are stored in buffers that are accessible for further event filtering by an on-line, processor farm. Data are transported to the farm only as they are needed by the higher-level trigger algorithms, leading to a reduced bandwidth requirement in the Data Acquisition System.
1994-04-01
Energy Technology Data Exchange (ETDEWEB)
Estonia is rich in such renewable energy sources like wood, peat and wind. Wind energy potential is very high (up to 7 TWh) due to its geographical location. Wind potential could be efficiently used particularly on the western coast and on islands. Wider use of renewable energy sources would allow significant cutting of GHG emissions. Wind energy yield reaches up to 9000 MWh in West-Estonian Archipelago, 4000-8000 MWh in other coastal regions and up to 4000 MWh in inland areas per 2 MW wind turbine. In Estonian coastal regions (20 km wide zone along the 3800 km long coastline) there is 114 000 ha (7.9% of total area) open fields that are fully suitable for harnessing wind energy. Use of wind energy has been hindered so far mainly by a systematic under-capacity operation of two large oil shale power plants in Narva and weak power network ...
2004-07-01
Visually Mediated Odor Tracking During Flight in Drosophila
UK PubMed Central (United Kingdom)
Flying insects use visual cues to stabilize their heading in a wind stream. Many animals additionally track odors carried in the wind. As such, visual stabilization of upwind tracking directly aids...Full Text Available
Publications related to the WIND ... - Glenn Research Center - NASA
Dippold, V., S. Mohler , Validation of the Wind-US Unstructured Flow Solver .... Hamed, A. and A. Mohamed, Assessment of Shock Induced Flow Separation and ...... Nozzles for Hypersonic Propulsion, NASA CR 185197, AGARD Symposium ...
Outlook for using wind energy for electrification of agriculture in Estonian SSR
Energy Technology Data Exchange (ETDEWEB)
The developed electrical networks in the agricultural regions of the Estonian SSR make it possible to construct relatively powerful wind power plants at the sites of the most favorable wind conditions with small outlays for the power transmission lines. The wind power plant electricity can be used to electrify the production processes in agriculture, while the surplus can be supplied to the energy system. The inclusion of the wind power plants in the energy system makes it possible to improve the total generation of energy or reduce the consumption of fuel. With the efficient arrangement of the wind power plants, one can also reduce the energy losses during its transfer. Calculations indicated that in the coastal zones of the Estonian SSR, one can obtain specific power of 420-480 kW/km/sup 2/. For comparison it is indicated that the Estonian SSR in the agricultural regions now uses ...
1982-01-01
Generation of intermediately-long sea waves by weakly sheared winds
The present work concerns the numeric modeling of the sea-wave instability under the effect of the logarithmic wind at hurricane conditions (ignoring non-linear effects, such as wave breaking, foam production, etc. Powell et al. (2003)^1, Shtemler et al. (2003)^2. The central point of the study is the calculation of the growth rate, which is proportional to the fractional input energy from the wind to the wave exponentially varied with time. The present modeling demonstrates that the Miles-type model applying Charnock's formula Charnock (1955)^3 for roughness to the hurricane -wind parameters underestimates the growth rate of the wind waves 5-40 times as compared with the model employing the roughness and friction velocity adopted from experimental data for hurricane winds.^1 This occurs due to Charnock's formula fails at large wind speeds. The stability ...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
A procedure has been developed for judging one-pile foundations for wind turbines. It appears that these foundations are good alternatives for block foundations. It is recommended to develop a program for testing one-pile foundations and to carry out a further research into their dynamic behavior.
1986-01-01
Design, Construction, Testing and Manufacturing of Vertical Axis Wind Turbines.
A substantial design and development program has been underway in the United States of America on the Darrieus vertical axis wind turbine (VAWT). The purpose of this report is to present currently available information on: design, construction, and testin...
1978-01-01
Major stellar-wind emission features in the spectrum of Eta Car have recently decreased by factors of order 2 relative to the continuum. This is unprecedented in the modern observational record. The simplest, but unproven, explanation is a rapid decrease in the wind density.
2010-01-01
Wind-To-Hydrogen Project: Operational Experience, Performance Testing, and Systems Integration
Energy Technology Data Exchange (ETDEWEB)
The Wind2H2 system is fully functional and continues to gather performance data. In this report, specifications of the Wind2H2 equipment (electrolyzers, compressor, hydrogen storage tanks, and the hydrogen fueled generator) are summarized. System operational experience and lessons learned are discussed. Valuable operational experience is shared through running, testing, daily operations, and troubleshooting the Wind2H2 system and equipment errors are being logged to help evaluate the reliability of the system.
2009-03-01
Vertical-axis wind turbines -- The current status of an old technology
Energy Technology Data Exchange (ETDEWEB)
Vertical-axis wind turbine technology is not well understood, even though the earliest wind machines rotated about a vertical axis. The operating environment of a vertical-axis wind turbine is quite complex, but detailed analysis capabilities have been developed and verified over the last 30 years. Although vertical-axis technology has not been widely commercialized, it exhibits both advantages and disadvantages compared to horizontal-axis technology, and in some applications, it appears to offer significant advantages.
1996-12-31
... 2-93 An Atmospheric Particle Emits Electromagnetic ... atmospheric water vapor produces a hydrometeor. ... subject to wind movement (either blowing ...
2003-06-13
Local wind patterns for modelling renewable energy systems by means of cluster analysis techniques
Energy Technology Data Exchange (ETDEWEB)
A method based on cluster analysis techniques is proposed in order to obtain representative local wind patterns. Modeling renewable energy systems, in an accurate way which strongly depends on wind loads, requires reliable data to analyze their response and evaluate their performance. Otherwise poor agreement with the models may be obtained. In a case study for La Paz, Baja California Sur, Mexico, four different wind patterns were obtained from a one-year data set recorded at 10-min intervals. (author)
2002-02-01
Transpiration and hydraulic traits of old and regrowth eucalypt forest in southwestern Australia
British Library Electronic Table of Contents (United Kingdom)
We tested the hypothesis that overstorey of eucalypt forest dominated by tall, large diameter trees uses less water than regrowth stands in the high rainfall zone (>1100mmyear^-^1) of the northern jarrah (Eucalyptus marginata) forest in southwestern Australia. We measured leaf area, cover, sapwood area and sapwood density at three paired old and regrowth stands. We also measured sapflow velocity at one paired stand (Dwellingup) from June 2007 to October 2008. Old stands had more basal area but less foliage cover, less leaf area and slightly thinner sapwood. The ratio of sapwood area to basal area decreased markedly as tree size increased. Sapwood area of the regrowth forest stands (6.6+/-0.30m^2ha^-^1) was nearly double that of the old stands (3.4+/-0.17m^2ha^-^1), despite larger basal are...
2010-01-01
Evaluation of a stack: A concrete chimney with brick liner
Energy Technology Data Exchange (ETDEWEB)
A 200 ft. tall stack, consisting of a concrete chimney with an independent acid proof brick liner built in the 1950`s, serving the Separations facility at the Savannah River Site (SRS), was evaluated for the performance category 3 (PC3) level of Natural Phenomena Hazards (NPH) effects. The inelastic energy absorption capacity of the concrete chimney was considered in the evaluation of the earthquake resistance, in particular, to compute the F{sub {mu}} factor. The calculated value of F{sub {mu}} exceeded 3.0, while the seismic demand for the PC3 level, using an F{sub {mu}} value of 1.5, was found to be less than the capacity of the concrete chimney. The capacity formulation of ACI 307 was modified to incorporate the effect of an after design opening on the tension side. There are considerable uncertainties in determining the earthquake resistance of the independent brick liner. The critical liner section, located at the bottom of the breeching opening, does not ...
1995-12-31
Energy Technology Data Exchange (ETDEWEB)
Increases in atmospheric CO[sub 2] are predicted to cause an increase in the C:N ratio of plant substrates entering the soil organic matter pool. We experimentally increased soil C:N ratios by adding 40 g C/m[sup 2] as sucrose (metabolic C) or cellulose (structural C) in short-, mid-, and tall-grass plots in the Serengeti Ecosystem, and measured plant productivity, plant nutrient uptake rates, and mineralization rates. Experimental treatments also included fencing to exclude grazing and additions of 40 g N/m[sup 2] as urea to simulate a urine hit from an average-sized ungulate. Productivity was only 60% of controls in C-addition plots, and was similar for sucrose and cellulose. However, this response was not observed in the short-grass site, an area of relatively low rainfall and high fertility. These results support the role of a plant-microbe negative feedback mechanism on plant growth in which increased C to microbes results in increased immobilization, reduced ...
1994-06-01
Wind tunnel modeling of heat islands in a turbulent boundary layer
International Nuclear Information System (INIS)
The basic studies of this report, had been done with a wind tunnel. Model similarity with typical atmospheric situations - such as an urban heat island - had to exist. Sufficient heat is needed to generate turbulent convection at the ground. By omitting the Boussinesq-approximation proper similarity parameters could be found to present the results in a dimensionless form. Also the effect of a cross circulation was investigated as well as the question at which conditions the convection is no longer able to overcome the longitudinal momentum of the wind. (KW).
Energy Technology Data Exchange (ETDEWEB)
The authors propose using synthetic aperture radar(SAR) for wind energy mapping of coastal zones. The SAR equipment is located on the European Space Agency ERS-1 and 2 and the RADARSAT satellites. Examples of wind energy maps and evaluations of their applications are given for the Norwegian west coast.
2000-07-01
Tailored airfoils for vertical axis wind turbines
Energy Technology Data Exchange (ETDEWEB)
The evolution of a family of airfoil sections designed to be used as blade elements of a vertical axis wind turbine (VAWT) is described. This evolution consists of extensive computer simulation, wind tunnel testing and field testing. The process reveals that significant reductions in system costs-of-energy and increases in fatigue lifetime may be expected for VAWT systems using these blade elements.
1984-11-01
Plume spread and atmospheric stability
Energy Technology Data Exchange (ETDEWEB)
The horizontal spread of a plume in atmospheric dispersion can be described by the standard deviation of horizontal direction. The widely used Pasquill-Gifford classes of atmospheric stability have assigned typical values of the standard deviation of horizontal wind direction and of the lapse rate. A measured lapse rate can thus be used to estimate the standard deviation of wind direction. It is examined by means of a large dataset of fast wind measurements how good these estimates are. (author) 1 fig., 2 refs.
1999-08-01
Energy Technology Data Exchange (ETDEWEB)
Whooper swans habitat in the coastal regions of Denmark can be affected by wind turbine arrays on the coast. The planned array consists of 55 wind turbines very close to the swan breeding area. A possibility of moving the swans away from the windmill area would be to spread the preferred swan feeds (rape, potatoes) outside their present breeding ground. (EG) 14 refs.
1998-06-01
Development of Vertical Axis Wind Turbines Darrieus Type, 5M Diameter, at Grenoble (France).
The Centre d'Etudes Nucleaires de Grenoble (France) has constructed nine Vertical Axis Wind Turbines (VAWT), of Darrieus type, 5 m diameter (D5), in order to acquire a wide knowledge of this kind of wind turbines and of its performances, the final goal be...
1984-01-01
Energy Technology Data Exchange (ETDEWEB)
The Atlantic Wind Test Site was established in 1980 as a laboratory to facilitate the evaluation and demonstration of wind energy systems and equipment. This annual report describes its organization and management, facilities, major projects, and the outlook for the future. Major projects include wind diesel; AWTS-IREQ collaboration; remote community data acquisition; lagerwey test program; Alaska Energy Authority Project; public education; Atlantic Orient Corporation 15/50 Project; and the soft VAWT project.
1994-12-31
A new control strategy for tracking peak power in a wind or wave energy system
Energy Technology Data Exchange (ETDEWEB)
This paper proposes a novel control strategy for tracking peak power in a wind or wave energy system using a squirrel cage induction generator. It eliminates wind speed measurement or estimation and uses a simple scalar technique by exploiting the cubic nature of the power curve. The method works even when air velocity is varying dynamically. (author)
2009-06-15
International Nuclear Information System (INIS)
The radio, optical, x-ray and gamma-ray nebulae that surround many pulsars are thought to arise from synchrotron and inverse Compton emission. The energy powering this emission as well as the magnetic fields and relativistic particles are supplied by a 'wind' driven by the central object. The inner parts of the wind can be described using the equations of MHD, but these break down in the outer parts, when the density of charge carriers drops below a critical value. This paper reviews the wave properties of the inner part (striped wind), and uses a relativistic two-fluid model (cold electrons and positrons) to re-examine the nonlinear electromagnetic modes that propagate in the outer parts. It is shown that in a radial wind, two solutions exist for circularly polarized electromagnetic modes. At large distances one of them turns into a freely expanding flow containing a vacuum wave, whereas the other ...
2010-12-01
Statistical analyses of coads wind data in coastal regions of the United States
Energy Technology Data Exchange (ETDEWEB)
In the study, wind data from the Comprehensive Ocean-Atmosphere Data Set (COADS) are used to determine atmospheric circulation changes which are empirically associated with the air temperature changes. Some understanding of the natural processes which produce climate change is anticipated from the study of these associations. Systematic changes of wind in US coastal regions with periods of climate warming and cooling suggest circulation changes, in addition to carbon dioxide-controlled radiation effects, could produce the climate changes indicated by air temperature. A statistical procedure for analyses of COADS was used to determine decade-period vector wind-field differences from the COADS record period. The statistical procedure for these analyses is explained and the wind differences are compared to summaries of mid-Atlantic coast island-station observations.
1992-08-01
Radiation from Relativistic Strongly Magnetized Outflows
Relativistic strongly magnetized winds outflowing from fast-rotating compact objects like millisecond pulsars with surface magnetic fields of $\\sim 10^{15}-10^{16}$ G are plausible sources of cosmological $\\gamma$-ray bursts. In such winds, there are at least three regions where extremely powerful X-ray and $\\gamma$-ray emission may be generated. The first radiating region is the wind photosphere that is at a distance of $\\sim 10^9$ cm from the compact object. The second radiating region is at a distance of $\\sim 10^{13}-10^{14}$ cm. In this region, the striped component of the wind field is transformed into large-amplitude electromagnetic waves. The third radiating region is at a distance of $\\sim 10^{16}-10^{17}$ cm, where deceleration of the wind due to its interaction with an ambient medium becomes important. Radiation from all these regions is considered.
1999-01-01
Theoretical and experimental research efforts in evaluating an innovative concept for vertical axis wind turbines (VAWT) are described. The concept is that of using straight blades composed of circulation controlled airfoil sections. The theoretical analysis has been developed to determine the unsteady lift and moment characteristics of multiple-blade cross-flow wind turbines. To determine the drag data needed as input to the theoretical analysis, an outdoor test model VAWT has been constructed; design details, instrumentation, and calibration results are reported. Initial testing is with fixed pitch blades having cross-sections of conventional symmetrical airfoils. Costs of building the test model are included, as well as estimates for blades constructed with composite materials. These costs are compared with those of other types of wind turbines.
1978-10-01
Doppler lidar mounted on a wind turbine nacelle - UPWIND deliverable D6.7.1
Energy Technology Data Exchange (ETDEWEB)
A ZephIR prototype wind lidar manufactured by QinetiQ was mounted on the nacelle of a Vestas V27 wind turbine and measurements of the incoming wind flow towards the rotor of the wind turbine were acquired for approximately 3 months (April - June 2009). The objective of this experiment was the investigation of the turbulence attenuation induced in the lidar measurements. In this report are presented results from data analysis over a 21-hour period (2009-05-05 12:00 - 2009-05-06 09:00). During this period the wind turbine was not operating and the line-of-sight of the lidar was aligned with the wind direction. The analysis included a correlation study between the ZephIR lidar and a METEK sonic anemometer. The correlation analysis was performed using both 10 minutes and 10 Hz wind speed values. The spectral transfer function which describes the ...
2010-12-15
Energy Technology Data Exchange (ETDEWEB)
A wind turbine is disclosed which permits high energy production over a wide range of wind forces while being protected against climatic hazards. According to the invention, a mast supports an energy recuperator comprising vane-type rotors by means of a frame which is orientable around a vertical axis. An energy conversion device is connected to the recuperator in order to be driven in rotation by the recuperator. The frame is responsive to the aerodynamic force exerted on the recuperator with respect to the mast and to the ground so as to optimize the power collected by the machine. The frame comprises a turret pivoted to the mast about the vertical axis and a structure pivoted to the turret about a horizontal axis of tilting motion. A balance weight maintains the recuperator in the top position when there is no wind. The aerodynamic drag of the recuperator acts in the opposite direction. In consequence, in the event of a ...
1991-12-19
Generation of intermediately-long sea waves by weakly sheared winds
The present work concerns the numeric modeling of the sea-wave instability under the effect of the logarithmic-wind profile at hurricane conditions. Non-linear effects, such as wave breaking, foam production, etc. Powell et al. (2003), Shtemler et al. (2010) are ignored. The central point of the study is the calculation of the wave growth rate, which is proportional to the fractional input energy from the wind to the wave exponentially varied with time. The present modeling demonstrates that the Miles-type model applying Charnock's formula for roughness to the hurricane-wind parameters underestimates the growth rate from 5 to 40 times as compared with the model employing the roughness and friction velocity adopted from experimental data for hurricane winds.1 This occurs due to Charnock's formula fails at large wind speeds. The stability characteristics found on the base of the ...
2010-01-01
Electrical wind generation, feasibility study and analysis in Lebanon
International Nuclear Information System (INIS)
Full text.This paper is to investigate the potentials and possibilities of electrical generation via wind turbine. Special attention is directed to the interpretation of wind generation characteristics and parameters found in Lebanon and linking the electrical energy to the Lebanese slectric grid. Although much of the wind energy research is very well established and boomed globally (USA, Europe, India and China), in Lebanon is never used. At a time when climate scientists are increasingly concerned about carbon dioxide emissions from coal and diesel plants, and the nuclear industry is drying, the significance of a major new source os electricity is clear. there are many motives and feasibility criteria for qind power generation in Lebanon. They include the need for increasing the Lebanese electrical capacity, reducing air pollution, alternative energy sources and prices and availability of oil. The work will include ...
1999-11-02
Depleted uranium human health risk assessment, Jefferson Proving Ground, Indiana
Energy Technology Data Exchange (ETDEWEB)
The risk to human health from fragments of depleted uranium (DU) at Jefferson Proving Ground (JPG) was estimated using two types of ecosystem pathway models. A steady-state, model of the JPG area was developed to examine the effects of DU in soils, water, and vegetation on deer that were hunted and consumed by humans. The RESRAD code was also used to estimate the effects of farming the impact area and consuming the products derived from the farm. The steady-state model showed that minimal doses to humans are expected from consumption of deer that inhabit the impact area. Median values for doses to humans range from about 1 mrem ({plus_minus}2.4) to 0.04 mrem ({plus_minus}0.13) and translate to less than 1 {times} 10{sup {minus}6} detriments (excess cancers) in the population. Monte Carlo simulation of the steady-state model was used to derive the probability distributions from which the median values were drawn. Sensitivity analyses of the ...
1994-04-29
Energy Technology Data Exchange (ETDEWEB)
The characteristics of diesel fuel jet atomization in carburetors depend on dynamic viscosity (v) density (d) and surface tension (st) of fuel, grouped in the combined functions v/d; st/v and st/d. Values of these combined functions for binary mixtures of a farm diesel fuel with a crude vegetable oil (sunflower, soybean, cotton and foot-cake olive oils) as well as with a used frying olive oil, are calculated. Three different diesel fuels have been studied. Combined function values of these mixtures are influenced by the characteristics of their diesel fuel. Mixtures containing less than 24% of any studied crude oils show kinematic viscosity values at 40 degrees C not exceeding 5.8 squared millimeters/s. This value is the higher limit for typical United States farm diesel fuels, according to specifications of the Cummins Engine Company. Mixture with 21% of the used frying olive oil shows at 40 degrees C this kinematic viscosity.
1985-09-01
Environmental data for sites in the National Solar Data Network
Energy Technology Data Exchange (ETDEWEB)
The environmental data for the NSDN are presented in the form of tables for each solar site. The solar sites are grouped into 12 zones, each of which consists of several adjacent states. The solar energy sites are in alphabetical sequence within each zone. The tables provide available meteorological data for reporting sites in the NSDN as follows: Insolation - the insolation table presents the total, diffuse, direct, maximum, and extra-terrestrial radiation for the solar site. It also shows the ratio of total extra-terrestrial radiation, as a percent. Temperature - the temperature table gives the average, daytime, nightime, maximum, minimum and inlet-water temperatures for the solar site. Additional tables are presented for some of these NSDN sites, supplying either wind or relative humidity data, or both. Wind - all of the passive and some of the active solar sites are equipped with wind sensors. These provide information ...
1980-12-01
The role of RFID in agriculture: Applications, limitations and challenges
British Library Electronic Table of Contents (United Kingdom)
The recent advances in RFID offer vast opportunities for research, development and innovation in agriculture. The aim of this paper is to give readers a comprehensive view of current applications and new possibilities, but also explain the limitations and challenges of this technology. RFID has been used for years in animal identification and tracking, being a common practice in many farms. Also it has been used in the food chain for traceability control. The implementation of sensors in tags, make possible to monitor the cold chain of perishable food products and the development of new applications in fields like environmental monitoring, irrigation, specialty crops and farm machinery. However, it is not all advantages. There are also challenges and limitations that should be faced in the...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The economic development of eastern Europe was associated during the last 15 years with the following average annual increases in energy consumption: Approximately 1% in the sectors industry, building and transport, almost 7% in the farming sector, approximately 3% in households, and nearly 4% in the municipal sector. This trend will not continue. As the economic system shifts from centrally planned to free economy and as the previously secluded economy is forced to face world market conditions as well as changed pars of exchange and conditions of payment, it not only experiences a transitory, sharp dip of economic growth in general but, in particular, drastic structural changes. - While there is to be expected, on the whole a slump in national economic growth, in tradiational branches of industry (e.g., metallurgy, the chemicals and textile industry) as well as in farming, such sectors as the service industry and small trade are expanding. ...
1991-10-01
Energy Technology Data Exchange (ETDEWEB)
This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a project that involves the building of a joint biogas plant serving 60 farmers and industrial companies with an annual processing capacity of 45,000 tons. The plant is to produce biogas to be fed into the gas mains and will not only reduce nutrient loading in a region with an extensive livestock industry but also reduce carbon dioxide emissions by using the gas as a motor fuel. The importance of the project with respect to both the environment and energy policy-making is discussed and the costs involved are examined. Details are presented on the technology used and on the material flows involved. Figures are quoted on energy production. The various biogenic substrates used, such as food wastes, waste oils, cereal wastes and used mushroom substrates, are discussed, as is the use of the solid and liquid outputs of the digester in farming activities.
2005-07-01
British Library Electronic Table of Contents (United Kingdom)
Purpose The mangroves of New Caledonia, in the south Pacific, act as a buffer between a lagoon of more than 20,000?km2 and the island, which is characterized by ultramafic rocks and lateritic soils that are exploited for their richness in heavy metals. We will provide a better understanding of the redox conditions, and of heavy metal distributions in mangroves receiving shrimp farm effluents. Materials and methods Samples were collected from four areas defined in terms of vegetation composition: a salt flat, an Avicennia marina forest, in which effluents are released; a Rhizophora stylosa forest, and a dead Rhizophora forest. They were collected during times of maximum effluent release. Some measurements on pore water were also done during a period without effluent. Cores (70?cm deep) were...
2011-01-01
Real-time configuration changes of the ATLAS High Level Trigger
The ATLAS High Level Trigger (HLT) is a distributed real-time software system that performs the final online selection of events produced during proton-proton collisions at the Large Hadron Collider (LHC). It is designed as a two-stage trigger and event filter running on a farm of commodity PC hardware. Currently the system consists of about 850 processing nodes and will be extended incrementally following the expected increase in luminosity of the LHC to about 2000 nodes. The event selection within the HLT applications is carried out by specialized reconstruction algorithms. The selection can be controlled via properties that are stored in a central database and are retrieved at the startup of the HLT processes, which then usually run continuously for many hours. To be able to respond to changes in the LHC beam conditions, it is essential that the algorithms can be re-configured without disrupting data taking while ensuring a consistent and reproducible ...
2010-01-01
British Library Electronic Table of Contents (United Kingdom)
The Pacific white shrimp, Litopenaeus vannamei, is the most important shrimp species in volume in world aquaculture. However, in recent decades, outbreaks of diseases, especially viral diseases, have led to significant economic losses, threatening the sustainability of shrimp farming worldwide. In 2004, Brazilian shrimp farming was seriously affected by a new disease caused by the Infectious myonecrosis virus (IMNV). Thus, disease control based on rapid and sensitive pathogen detection methods has become a priority. In this study, a specific quantitation method for IMNV was developed using real-time PCR with SYBR Green chemistry and viral load of the principal target tissues of chronically infected animals was quantified. The quantitative analysis revealed that mean viral load ranged from ...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
Abstract Development of inhibitors and vaccines that mitigate rumen-derived methane by targeting methanogens relies on knowledge of the methanogens present. We investigated the composition of archaeal communities in the rumens of farmed sheep (Ovis aries), cattle (Bos taurus) and red deer (Cervus elaphus) using denaturing gradient gel electrophoresis (DGGE) to generate fingerprints of archaeal 16S rRNA genes. The total archaeal communities were relatively constant across species and diets, and were less variable and less diverse than bacterial communities. There were diet- and ruminant-species-based differences in archaeal community structure, but the same dominant archaea were present in all rumens. These were members of three coherent clades: species related to Methanobrevibacter ruminan...
2011-01-01
Lead, cadmium, chromium, cobalt, and copper in chicken feathers from Tuskegee, Alabama
Energy Technology Data Exchange (ETDEWEB)
The feather has been widely used as a indicator tissue of metal exposure in birds. The feathers were collected from Tuskegee University poultry farm (TUPF) and Harrison Poultry farm (HPF) chicken and analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy for lead, cadmium, cobalt, chromium, and copper contaminations. The mean levels of lead, cadmium, cobalt, chromium, and copper in TUPF chicken were 3.67, 0.13, 12.23, 0.22, and 7.71 ppm, respectively, and in HPF chicken were 5.32, 0.096, 11.03, 0.15, and 8.06 ppm, respectively. The mean levels of these metals did not show any significant difference between TUPF and HPF chicken.
1994-12-31
Exploration of the hypothalamic?pituitary?adrenal function as a tool to evaluate animal welfare
British Library Electronic Table of Contents (United Kingdom)
Measuring HPA axis activity is the standard approach to the study of stress and welfare in farm animals. Although the reference technique is the use of blood plasma to measure glucocorticoid hormones (cortisol or corticosterone), several alternative methods such as the measurement of corticosteroids in saliva, urine or faeces have been developed to overcome the stress induced by blood sampling itself. In chronic stress situations, as is frequently the case in studies about farm animal welfare, hormonal secretions are usually unchanged but dynamic testing allows the demonstration of functional changes at several levels of the system, including the sensitization of the adrenal cortex to ACTH and the resistance of the axis to feedback inhibition by corticosteroids (dexamethasone suppression t...
2007-01-01
Assessing soil quality under intensive cultivation and tree orchards in Southern Italy
British Library Electronic Table of Contents (United Kingdom)
Concerns about groundwater contamination as well as pesticide residues in food and soil have fuelled vigorous debates about the sustainability of chemical-intensive agriculture. Search has been prompted for agronomic strategies with lower environmental hazards. In this multidisciplinary study we compared the characteristics of soils from 20 agricultural farms selected in five geographical areas of Southern Italy with different soil types. In each farm, fields with management regime classified as high-input (HIMR, intensive cultivation under plastic tunnels) or low-input (LIMR, tree orchards) were selected. Soil samples were analyzed for 31 parameters including physical and chemical properties (bulk density, water holding capacity, texture, pH, limestone, electrical conductivity, organic C ...
2011-01-01
Assessing farm-level agricultural sustainability over a 60-year period in rural eastern India
British Library Electronic Table of Contents (United Kingdom)
Agricultural sustainability is a vital parameter to be ascertained locally and globally if food security is to be achieved and maintained. Agricultural sustainability is the combined product of social, economic and ecological sustainability. It is also a function of temporal and spatial variations, a fact which indicates that area-specific sustainability indices need to be designed. We present here an Agricultural Sustainability Index (ASI) for rural eastern India and use it to calculate the ASI for 150 farms for three decades over a 60-year period, viz., 1950?1960, 1980?1990 and 2000?2010 for a representative Indian village of Gangapur (25?83?N, 85?65?E). The ASI was calculated using 30 variables, 10 each of social, economic and ecological sustainability. An extensive questionnaire-based ...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
We show that the HACCP system is not fully applicable at the primary production level, and that food safety is obtained through the careful implementation of good hygiene practice (GHP) at the farm. Guides to GHP intended at primary productions cover one activity, such as cattle rearing or corn production. Yet most farms have more than one activity. Hazards from one activity can be transferred to another activity, and in general this is not considered in one-activity guides. There is a need therefore for farmers to be able to detect and control such transfers. We suggest a horizontal complement to the Guides to GHP that would consider only the application of the Step 6 and Principle 1 of the HACCP system amended as follows: ''List all potential hazards transferred from one activity to anot...
2011-01-01
Wind loss prevention for open cavity solar receivers
Energy Technology Data Exchange (ETDEWEB)
Apparatus for minimizing thermal loss in a windowless, open cavity solar receiver due to airflow at the receiver aperture includes means for deflecting wind away from the cavity opening such that flow stream reattachment occurs away from the receiver aperture to provide a dead air zone at the cavity opening. This prevents turbulent-mixing airflow exchange between ambient air and heated air within the solar receiver. The wind deflector apparatus includes either a passive annular deflection foil at the receiver aperture, or an active device for producing an outwardly projected air jet at the receiver aperture.
1982-01-26
Rotational modes of motion for an aerodynamic pendulum with a vertical rotation axis
British Library Electronic Table of Contents (United Kingdom)
An aerodynamic pendulum placed in a steady horizontal air flow is studied in connection with modeling a wind-receiving element of a vertical-axis wind turbine (VAWT). When modeling the medium effects on the pendulum, the following two approaches are combined: the quasi-static one based on stationary wind tunnel experiments and the unsteady one based on the added mass effects. The existence of stable and unstable rotational modes is analyzed analytically (via the Poincar?-Pontryagin method) and numerically. The dependence on the parameters responsible for the viscous friction at the rotation axis and for the added mass effects is taken into account.
2009-01-01
Directional wind-measurement derived from elastic backscatter lidar data in real-time
Energy Technology Data Exchange (ETDEWEB)
The development of a capability to infer wind velocities simultaneously at a number of ranges along one direction in real time is described. The elastic backscatter lidar data used was obtained using the XM94 lidar, developed by Los Alamos National Laboratory for the US Army Chemical and Biological Detection Command. In some respects this problem is simpler than measuring wind velocities on meso-meteorological scales. Other requirements, particularly high temporal fidelity, have driven the development of faster software algorithms and suggested opportunities for the evolution of the hardware.
1996-04-01
Determination of the Venezuelan coastal-zone wind atlas by using numerical methods
Energy Technology Data Exchange (ETDEWEB)
This work deals with the development of wind maps in the Venezuelan coastal zones (South America). The Navier-Stokes equations for real viscous incompressible flow are discretized via the finite element method and they are applied to a full 3D numerical model. Two regions were analyzed: the Margarita island and the Paraguana peninsula, both of them located in the Caribbean Sea at the North of Venezuela. These regions were modeled by using a three dimensional control volume, discretized through hexaedric eight-noded finite elements. Some wind maps obtained in this research are presented and discussed. (author)
1995-12-31
Aspects of unsteady aerodynamics in wind turbines
Energy Technology Data Exchange (ETDEWEB)
This presentation is primarily about unsteady aerodynamics in relation to wind turbines. It is divided into three very distinct sections: (1) Basic unsteady aerodynamics; (2) VAWT performance modelling and (3) Passive stall regulation of VAWTs. The aim of the presentation is to illustrate that, if desired, future wind turbine blades could be aerodynamically tailored to exploit the unsteady nature of the VAWT flow with far greater confidence and insight than has been hitherto possible. To this effect, the collaborating British research teams and, in particular, VAWT Ltd. have assembled sufficient knowledge for such a conclusion to be made. (author).
1990-01-01
A 34-meter VAWT (Vertical Axis Wind Turbine) point design
The Wind Energy Division at Sandia National Laboratories recently completed a point design based on the 34-m Vertical Axis Wind Turbine (VAWT) Test Bed. The 34-m Test Bed research machine incorporates several innovations that improve Darrieus technology, including increased energy production, over previous machines. The point design differs minimally from the Test Bed; but by removing research-related items, its estimated cost is substantially reduced. The point design is a first step towards a Test-Bed-based commercial machine that would be competitive with conventional sources of power in the mid-1990s.
1991-01-01
X-ray Emission as a Probe of the Wind-Driven Shock in WR 140
single star evolution. To understand the evolution of massive stars and their role in shaping the galaxy, understanding of the distribution of ...
Wind systems life cycle cost analysis: a description and users manual. [LIFECC
Energy Technology Data Exchange (ETDEWEB)
This report describes the LIFECC computer program developed for the purpose of calculating the cost of energy produced by wind systems according to the principles of life cycle costing (LCC). Following a brief explanation of the LCC concept and its advantages, input variables to the program and their importance to various program users, including manufacturers and designers, utilities, various institutions and consumers, are explained. A detailed user's guide to the program is then provided, together with a sensitivity analysis which discusses the impact of key variables on wind system cost of energy and the importance of cash flow to the wind system purchaser. Sample cases of program output and an LIFECC program listing are provided.
1982-07-01
Wind and Wave Forcing of Longshore Currents Across a ...
... These assumptions are quantitatively investigated by calculating tie icldti\\e inportance of ... A modified lon-shore current model is used to study the ...
1988-06-01
Wind Tunnel Flow Quality and Data Accuracy Requirements
... tests, one often encounters, for instance, separated flows with large ... It is suspected that the flow-quality criteria given in AGARD Report No. ...
1982-11-01
Toxicity of Jet A (Aviation Fuel) Selected Aquatic Organisms
... Descriptors : *JET ENGINE FUELS, *AQUATIC ORGANISMS, *AVIATION FUELS, *TOXICITY, HEALTH, SMOKE SCREENS, WIND, WATER ...
1989-03-01
STUDY OF METEOR WIND MEASUREMENT TECHNIQUES. ...
... of a secondary standard (VCO) locally available. ... phase of the local secondary standards to the 10-min average of the phase of ... I3a - - \\.-e-~--. ...
1970-02-01
Rethinking development assistance for wind power
Energy Technology Data Exchange (ETDEWEB)
Electricity generation from wind turbines is now cost competitive for grid and off-grid applications in many developing regions, and close to competitive in others. Wind resources could generate thousands of megawatts of badly-needed power in Asia, North Africa, and Latin America. Barriers to penetrating power generation markets remain, however, including unequal access to investment capital, energy price and other market distortions, and often weak institutions for commercializing new technologies. Recognizing the potential economic and environmental benefits of wind power, bilateral and multilateral assistance organizations have for several years offered financial and technical assistance to promote its diffusion. Based on this experience and assistance for other renewable electric technologies, lessons and recommendations can be drawn regarding how assistance could more effectively overcome persistent market and policy ...
1995-12-31
Published ... - Wind Tunnels | NASA Ames Research Center - NASA
Sep 5, 2008 ... Russia. The six-component balance for blunt models aerodynamic force measurement in shock tunnel. Lu Zhiquo, Liu Hongshan, Zhang Yan ...
Power correlation for vertical axis wind turbines with varying geometries
British Library Electronic Table of Contents (United Kingdom)
Abstract In this paper, a new predictive model that can forecast the performance of a vertical axis wind turbine (VAWT) is presented. The new model includes four primary variables (rotor velocity, wind velocity, air density, and turbine power output) as well as five geometrical variables (rotor radius, turbine height, turbine width, stator spacing, and stator angle). These variables are reduced to include the power coefficient (Cp) and tip speed ratio (TSR). A power coefficient correlation for a novel VAWT (called a Zephyr Vertical axis Wind Turbine (ZVWT)) is developed. The turbine is an adaptation of the Savonius design. The new correlation can predict the turbine's performance for altered stator geometry and varying operating conditions. Numerical simulations with a rotating reference f...
2011-01-01
On the evolution of supernova remnants: Pt. 2
International Nuclear Information System (INIS)
Supernova explosions within wind-driven bubbles are studied with 2D hydrodynamical calculations. Two different density distributions for the ejecta are considered: (i) a smooth, unfragmented power-law stratification, and (ii) a fragmented distribution. As in 1D models, the presence of the shell of interstellar swept-up matter causes the rapid evolution of the remnant to the radiative phase. The main 2D effects, for both fragmented and unfragmented ejecta, include: (i) substantial chaotic deviations from a purely radial flow in the remnant interior, (ii) efficient turbulent mixing between the ejecta and the shocked wind, resulting in homogenization of the former wind cavity, and (iii) severe distortion of the wind-driven shell by cooling and Rayleigh-Taylor instabilities. (author).
Offshore Wind Electricity: A Viable Energy Option for the Coastal United States
Energy Technology Data Exchange (ETDEWEB)
This paper describes a wide range of technical research and development that can reduce costs and improve technology for deep water deployment.
2007-09-01
Nomographs estite floating-roof tank evaporation
Energy Technology Data Exchange (ETDEWEB)
Nomographs are presented that estimate the evaporation loss from external floating-roof tanks using tank diameter, type of seal, product vapor pressure, and wind velocity.
1986-01-27
Evolution in Space Radio Telescopes Reveal Youngest Stellar Corpse Gas Clouds in Whirlpool Galaxy Yield Important Clues Supporting Theory on Spiral Arms Starbust-driven Winds...
2011-10-09
NASA Research Announcement: GALEX GI Program Cycle 2 - GALEX - NASA
These include, but are not limited to: stellar winds and outflows, post-main- sequence stellar evolution, binary/multiple star evolution, globular cluster ...
NASA Research Announcement: GALEX GI Program Cycle 1 - GALEX - NASA
These include, but are not limited to: stellar winds and outflows, post-main- sequence star evolution, binary star evolution, globular cluster structure and ...
NASA Direct! - Kennedy Space Center - Home - NASA
Aug 21, 2003 ... Her research interests have included hot stars, colliding stellar winds, binary star evolution and evolved stellar companions. ...
Influence of the tidal wind system on the frequency of sporadic-E occurrence
International Nuclear Information System (INIS)
(Mar 1972). United States Harris, RD Taur, R. Logan, UT. 13 Sep 1971.
Improved double-multiple streamtube model for the Darrieus-type vertical axis wind turbine
Double streamtube codes model the curved blade (Darrieus-type) vertical axis wind turbine (VAWT) as a double actuator fish arrangement (one half) and use conservation of momentum principles to determine the forces acting on the turbine blades and the turbine performance. Sandia National Laboratories developed a double multiple streamtube model for the VAWT which incorporates the effects of the incident wind boundary layer, nonuniform velocity between the upwind and downwind sections of the rotor, dynamic stall effects and local blade Reynolds number variations. The theory underlying this VAWT model is described, as well as the code capabilities. Code results are compared with experimental data from two VAWT's and with the results from another double multiple streamtube and a vortex filament code. The effects of neglecting dynamic stall and horizontal wind velocity distribution are also illustrated.
1983-01-01
Golden coast on the Black Sea; Goldkueste am Schwarzen Meer
Energy Technology Data Exchange (ETDEWEB)
The most profitable terrain in Romania is already sold. Investors are now looking for new wind power sites. The contribution presents details. (orig.)
2007-06-15
Gearbox Reliability Collaborative Experimental Data Overview & Analysis (Presentation)
Energy Technology Data Exchange (ETDEWEB)
This presentation details how wind turbine gearboxes fail to meet 20-year design life and how the Gearbox Reliability Collaborative (GRC) is addressing the challenges.
2010-05-01
GTMO Portfolio - IRAD Funded - NASA
Apr 27, 2007... Bruce Gentry: Small, Efficient Direct Detection Doppler Receiver for UAV and Spaceborne measurement of Tropospheric Winds ...
GALAXY EVOLUTION EXPLORER (GALEX) - HEASARC - NASA
These include, but are not limited to: stellar winds and outflows, post-main- sequence stellar evolution, binary/multiple star evolution, globular cluster structure ...
GALAXY EVOLUTION EXPLORER (GALEX) - GALEX - NASA
These include, but are not limited to: stellar winds and outflows, post-main- sequence stellar evolution, binary/multiple star evolution, globular cluster structure ...
EUROPEAN SPACE AGENCY Extension of the SOHO Mission
closure of the BISON network, GOLF and VIRGO will remain the only instruments ...... Faraday Cup solar wind instrument as described in Ipavich et al (1998). ...
DYNAMIC ANALYSIS OF DARRIEUS VERTICAL AXIS WIND ...
The dynamic response characteristics of the VAWT rotor are important factors governing the safety and fatique life of VAWT systems. The principal problems are ...
Bibliography of Papers on the WIND CFD Code
Hamed, A. and A. Mohamed, "Assessment of Shock Induced Flow Separation and ...... AGARD Symposium on Combined Cycle Propulsion for Hypersonic Application, ...
This Dissertation presents the author's investigation and development of a systematic method for evaluating the aerodynamic performance of Vertical Axis Wind Energy Capture Systems (WECS) apart from their electrical generation capability. The current standard method for specifying a wind energy machine is to discuss its rated power in kilowatts (or megawatts when capacity exceeds 100 kW). While this holistic method is effective for comparing machines it does not reveal the essential characteristics necessary for optimization of individual machine components. The method developed herein separates the performance characteristics of the WECS from the generation characteristics and isolates them for benchmarking and optimization. In order to develop an evaluation criterion, it was essential to evaluate and benchmark the current state of the art for wind energy capture. A thorough history of Vertical Axis ...
2010-01-01
The use and value of information systems as evaluated by dairy and specialty crop farm managers.
Little recent research is available about where specific types of farm managers search for information about better production practices. The objective of this study was to investigate what information sources managers used and how they rated the usefulness of each source. The authors administered mail questionnaires to probability samples from sampling frames they developed for four groups: dairy and fresh market vegetable producers from Wisconsin and berry and nursery producers from a multistate region. Questionnaire items asked operation managers to check off, from a list of information sources, those that they used in the last year to learn about new equipment or procedures to improve their operations and then to rate the usefulness of each source. In the last year, nursery, dairy, and berry managers most often used information from print media (63% to 84%), followed by other farmers (50% to 80%). Fresh market vegetable growers used conferences (60%) most ...
2009-01-01
Energy Technology Data Exchange (ETDEWEB)
This paper shows and describes the actions and methodologies adopted in commercialization of rural electrification projects in Parana State, Brazil. The actions evaluated aims to feasible the techniques to farm owners provides them properties with electric power. 7 figs., 2 tabs., 1 ref.
1986-12-31
Renewable resources - prospects for the chemicals industry
International Nuclear Information System (INIS)
Improved boundary conditions for the cultivation and utilization of renewable feedstocks in Europe as well as advances in the manufacture and use of intermediate products, special and fine chemicals, and new materials on this basis were the topics of a second symposium, organized this time by Hoechst AG, together with the federal ministry of food, agriculture and forestry, in Frankfurt-Hoechst on May 5th and 6th. With more than 300 attendants from the sectors politics, farming, industry, science and administration, the meeting again encountered great interest. (orig.).
Projected radionuclide inventories of DWPF glass from current waste at time of production
Energy Technology Data Exchange (ETDEWEB)
The Waste Acceptance Preliminary Specifications (WAPS) require that the DWPF estimate the inventory of long-lived radionuclides present in the waste glass, and report the values in the Waste Form Qualification Report. In this report, conservative (biased high) estimates of the radionuclide inventory of glass produced from waste currently in the Tank Farm are provided. In most cases, these calculated values compare favorably with actual data. In those cases where the agreement is not good, the values reported here are conservative.
1993-02-04
UK PubMed Central (United Kingdom)
Broiler chickens from eight commercial farms in Southern Finland were analyzed for the structure of their gastrointestinal microbial community by a nonselective DNA-based method, percent G+C-based...Full Text Available
2001-12-01
Organic livestock production in Uganda: potentials, challenges and prospects.
Development in organic farming has been stimulated by farmers and consumers becoming interested in healthy food products and sustainable environment. Organic agriculture is a holistic production management system which is based on the principles of health, ecology, care, and fairness. Organic development in Uganda has focused more on the crop sector than livestock sector and has primarily involved the private sector, like organic products export companies and non-governmental organizations. Agriculture in Uganda and many African countries is predominantly traditional, less mechanized, and is usually associated with minimum use of chemical fertilizers, pesticides, and drugs. This low external input agriculture also referred to as "organic by default" can create basis for organic farming where agroecological methods are introduced and present an alternative in terms of intensification to the current low-input/low-output systems. Traditional ...
2011-01-12
Optimising nutrient use efficiency in beef cattle grazing lowland semi-natural pastures
Environmental Research Database
DescriptionThe switch from production-linked to environmental payments has focussed attention on the environmental impacts of farming. There is a growing awareness of the need to reduce the contamination of air with carbon dioxide, methane, ammonia and nitrogen gases (which contribute to the greenhouse effect) and to prevent the contamination of soil and water with excessive amounts of nitrogen, phosphorus and potassium. As beef production moves to become more sustainable and fully integrated with the wide [continued...
2007-01-30
Methane fermentation of agricultural wastes and domestic animal's wastes
Energy Technology Data Exchange (ETDEWEB)
Cattle and pig wastes, orange peels, compost, and grain husks were hydrolyzed in an alkaline medium to investigate the CH4 generation capacity. The respective CH4 production capacities from pig wastes and rice hulls were approximately 1 and approximately 0.1 L/g. The CH4 produced can be used to supplement energy requirements of farms.
1981-01-01
Energy Technology Data Exchange (ETDEWEB)
This document, the Standards/Requirements Identification Document (S/RID) Phase I Assessment Report for the subject facility, represents the results of an Administrative Assessment to determine whether S/RID requirements are fully addressed by existing policies, plans or procedures. It contains; compliance status, remedial actions, and an implementing manuals report linking S/RID elements to requirement source to implementing manual and section.
1996-09-30
UK PubMed Central (United Kingdom)
A nationwide surveillance for antimicrobial susceptibility in Escherichia coli strains isolated from food-producing animals in Japan was conducted from 1999 to 2002. Eighteen cefazolin-resistant...Full Text Available
2005-08-01
Drying of medicinal plants with solar energy utilization
Energy Technology Data Exchange (ETDEWEB)
In the paper, a potential of solar energy for drying of medicinal plants in Polish conditions is estimated and development of solar drying technologies is presented. The results of economic assessment of flat-plate solar collectors applied for drying of medicinal plants on a farm are promising. In some specific conditions, e.g. drying of wild grown medicinal plants in remote areas, even application of photovoltaic modules for driving of a fan of a solar dryer is a profitable option and enables easy control of the drying air temperature.
1997-10-01
Animal manure digestion systems in central Europe
Energy Technology Data Exchange (ETDEWEB)
This work provides an overview of existing plants in Europe and describes the substrates being used. It focuses on the individual farm-scale and community plants, as these are the two main types now being built. It also describes plants currently under construction, especially in Germany and Denmark, where the major efforts are focused. A description of how the technique has developed over the past few years, its current state of development, the motivation and economic balance, and the substrate characteristics, is presented.
1996-01-01
A non-invasive approach for the determination of rumen pH
Environmental Research Database
DescriptionAt present, measurement of rumen pH for differnt diets and feeding regimes is only possible through direct sampling of the rumen fluid. Such invasive procedures are not practical at the farm level and they have ethical implications for research programmes. This approach also has limitations to its reliability due to spatial variations in acidity within the rumen. Mathematical modelling offers a non-invasive real-time alternative for monitoring rumen pH, and the purpose of the research propose [continued...
2004-01-31
The model was based on a SEDCO 700 series semi-submersible offshore drilling rig used for operations in the North Sea. This report supplements earlier work on wind-heeling moments which are required to establish stability criteria on semi-submersibles. Wi...
1982-01-01
Wind instability of a foam layer sandwiched between the atmosphere and the ocean
Kelvin-Helmholtz instability of short gravity waves is examined in order to explain the recent findings of the decrease in momentum transfer from hurricane winds to sea waves. A three-fluid configuration of a foam layer between the atmosphere and the ocean is suggested to provide signifficant stabilization of the system and shifting the marginal critical wavelength to the shortwave part of the spectrum. It is conjectured that such stabilization leads to the observed drag reduction. The high contrasts in three fluid densities provide a universal mechanism for stabilizing surface perturbations.
2007-01-01
Wind-tunnel measurements were taken of the time-average aerodynamic forces and moments on a notional model of a semi-submersible offshore drilling rig at two heights and at various attitudes to the wind. Attempts were made to analyze the separate effects ...
1982-01-01
Energy Technology Data Exchange (ETDEWEB)
The completed ribbon-winding theory, including temperature loading of the high-pressure compound vessel, was proposed. The influence of the bending stress in the wound ribbon is taken into account. Internal core of the compound vessel consists of matrix and ring, made of different materials. The relations were derived in analytical form, describing the radial distribution of necessary tangential prestressing.
1996-11-01
The Legality of Wind and Altitude Assisted Performances in the Sprints
Based on a mathematical simulation which reproduces accurate split and velocity profiles for the 100 and 200 metre sprints, the magnitudes of altitude and mixed wind/altitude-assisted performances as compared to their sea-level equivalents are presented. It is shown that altitude-assisted times for the 200 metre are significantly higher than for the 100 metre, suggesting that the ``legality'' of such marks perhaps be reconsidered.
2001-01-01
Test and simulation of dynamic phase compensation from Mita-Teknik A/S
Energy Technology Data Exchange (ETDEWEB)
This report describes the test of a dynamic phase compensation unit for a wind turbine with directly connected induction generators. The compensation unit is based on thyristor switched capacitors, where conventional wind turbine compensations use mechanical contactors to switch the capacitors. The influence on power quality analysed, and influence on component lifetime is discussed. Besides, simulation models in Matlab/Simulink are presented, including a flicker meter model. (au)
2004-03-01
Superconducting magnetic system with the controllable inductance of a winding
International Nuclear Information System (INIS)
The experimental superconducting magnetic system of 0.5 MJ energy storage is described. The step variation of the winding inductance provides a control by the discharge current at the energy output on a high-ohmic load. The voltage on a load is 45 kV at the current 1100 A under the controllable discharge conditions. The energy transfer coefficient constitutes 0,76 under the maximum-to-minimal current ratio equal to 1.3. 7 refs., 3 figs., 2 tabs.
Recent Darrieus vertical axis wind turbine aerodynamical experiments at Sandia National Laboratories
Experiments contributing to the understanding of the aerodynamics of airfoils operating in the vertical axis wind turbine (VAWT) environment are described. These experiments are ultimately intended to reduce VAWT cost of energy and increase system reliability. They include chordwise pressure surveys, circumferential blade acceleration surveys, effects of blade camber, pitch and offset, blade blowing, and use of sections designed specifically for VAWT application.
1981-05-01
Proceedings of the Vertical Axis Wind Turbine (VAWT) Design Technology Seminar for Industry
The objective of the program is to develop technology that results in economical, industry produced, and commercially marketable wind energy systems. The purpose of the VAWT Design Technology Seminar for Industry was to provide for the exchange of the current state of the art and predictions for future VAWT technology. Emphasis was placed on technology transfer on Sandia's technical developments and on defining the available analytic and design tools.
1980-08-01
Nucleosynthesis in early supernova winds III: No significant contribution from neutron-rich pockets
Recent nucleosynthesis calculations of Type II supernovae using advanced neutrino transport determine that the early neutrino winds are proton-rich. However, a fraction of the ejecta emitted at the same time is composed of neutron-rich pockets. In this paper we calculate the nucleosynthesis contribution from the neutron-rich pockets in the hot convective bubbles of a core-collapse supernova and show that they do not contribute significantly to the total nucleosynthesis.
2007-01-01
Investigation into the fatigue behaviour of wood laminates for wind energy converter blade design
Energy Technology Data Exchange (ETDEWEB)
A thesis is presented on improving the understanding of the fatigue properties of wood and fatigue failure mechanisms in the design of wind turbine blades. Three main areas were researched: the effect of R ratio on fatigue life, the effect of moisture on fatigue life and the development of cumulative damage laws. Tests were carried out on mainly four-ply laminates. Recommendations to future work are outlined. (U.K.).
1987-01-01
Improved Double-Multiple Streamtube Model for the Darrieus-Type Vertical-Axis Wind Turbine.
Double streamtube codes model the curved blade (Darrieus-type) vertical-axis wind turbine (VAWT) as a double actuator-disk arrangement (one disk for the upwind half of the rotor and a second disk for the downwind half) and use conservation of momentum pri...
1983-01-01
Heat Stress When Wearing Body Armor.
This study evaluated the heat strain induced by six configurations of a new modular body armor (MBA) design. Tests were conducted in two environments differing only by wind speed. The environments were 40 deg C (104 deg F), 20% rh, wind speeds 1.0 msec-1 ...
2001-01-01
Wind turbulence used as searching signal for MPPT in variable-speed wind energy conversion systems
Energy Technology Data Exchange (ETDEWEB)
The control problem associated to a class of horizontal-axis fixed-pitch variable-speed low-power wind energy conversion systems, working in the partial load region, consisting in the energy conversion maximization, is approached here under the assumption that the wind turbine model and its parameters are poorly known. Using a new approach derived from the optimum seeking methods category, generically called Maximum Power Point Tracking (MPPT), the proposed control solution aims at driving the average position of the operating point near to optimality. Instead of inducing sinusoidal search signals, the wind turbulence is here used as search disturbance. The high-speed shaft's average rotational speed is slowly adjusted using the Fast Fourier Transform processing of some available measures from the system as an estimate of the operating point's position/distance to optimality. Numerical simulations are used ...
2009-01-15
Wind tunnel test on a straight wing vertical-axis wind turbine with attachment on blade surface
Energy Technology Data Exchange (ETDEWEB)
There is a renewed interest in straight wing vertical axis wind turbines (SW-VAWT) which are usually installed on the roofs of high buildings in cities, urban areas and high mountain areas for independent electric power supply. SW-VAWTs have the advantages of simple design and low cost, as well as wind direction independence compared to the horizontal system. However, when SW-VAWTs are installed in cold regions, ice, snow and other attachments can affect its performance. In this study, clay was attached to the leading edge of the blade surface to determine how the performance of SW-VAWTs are affected by the mechanism of icing. Wind tunnel tests were used to study the rotational performance and power performance of the turbine blades. Icing prevention was also investigated. The attachment of clay on the leading edge of blade surface made the rotational performance of the SW-VAWT worse. The attachment of clay on the leading ...
2008-07-01
Energy Technology Data Exchange (ETDEWEB)
The main objective of the present study is twofold: (i) to analyze thermal loads of the geothermally and passively heated solar greenhouses; and (ii) to investigate wind energy utilization in greenhouse heating which is modeled as a hybrid solar assisted geothermal heat pump and a small wind turbine system which is separately installed in the Solar Energy Institute of Ege University, Izmir, Turkey. The study shows 3.13% of the total yearly electricity energy consumption of the modeled system (3568 kWh) or 12.53% of the total yearly electricity energy consumptions of secondary water pumping, brine pumping, and fan coil (892 kWh) can be met by using small wind turbine system (SWTS) theoretically. According to this result, modeled passive solar pre heating technique and combined with geothermal heat pump system (GHPS) and SWTS can be economically preferable to the conventional space heating/cooling systems used in agricultural ...
2010-01-15
The impact of accretion disk winds on the X-ray spectrum of AGN: Part 1 - XSCORT
(abridged) The accretion disk in AGN is expected to produce strong outflows, in particular a UV-line driven wind. Despite providing a good fit to the data, current spectral models of the X-ray spectrum of AGN observed through an accretion disk wind are ad-hoc in their treatment of the properties of the wind material. In order to address these limitations we adopt a numerical computation method that links a series of radiative transfer calculations, incorporating the effect of a global velocity field in a self-consistent manner (XSCORT). We present a series of example spectra from the XSCORT code that allow us to examine the shape of AGN X-ray spectra seen through a wind, for a range of velocity and density distributions, total column densities and initial ionization parameters. These detailed spectral models clearly show considerable complexity and structure that is strongly affected by all these ...
2007-01-01
Structural design and fabrication of the Sandia 34-meter Vertical Axis Wind Turbine
The Wind Energy Research Division of Sandia National Laboratories has been funded by the Wind/Ocean Technology Division of the Department of Energy (DOE) to design and build a 34-meter diameter Vertical Axis Wind Turbine (VAWT). The turbine design incorporates the results of recent VAWT research in aerodynamics and structural dynamics. Initial system concept studies identified several blade options that met the required power rating of 500 kW. The final blade and rotor configurations were chosen based on finite element calculations that determined the turbine modes of response, their frequency of vibration, and stress levels. For parked survival turbine components were designed to with stand the loading of a 150 mph (67.0 m/s) wind coupled with maximum cable tensions. Specific areas of design discussed include the rotor, cables, bearings, brakes, and foundations. Construction of the turbine is in ...
1987-01-01
Double-Edge Molecular Measurement of Lidar Wind Profiles in the VALID Campaign
We have developed a transportable container based direct detection Doppler lidar based on the double-edge molecular technique. The pulsed solid state system was built at the University of Geneva. It was used to make range resolved measurements of the atmospheric wind field as part of the VALID campaign at the Observatoire de Haute Provence in Provence, France in July 1999. Comparison of our lidar wind measurements, which were analyzed without knowledge of the results of rawinsonde measurements made under the supervision of ESA, show good agreement with these rawinsondes. These are the first Doppler lidar field measurements made with an eyesafe direct detection molecular-based system at 355 nm and serve as a demonstrator for future spaceborne direct detection wind systems such as the Atmospheric Dynamics mission. Winds are an important contributor to sea surface temperature measurements made with the ...
2000-01-01
Canadian wind energy research and development status and perspectives
Energy Technology Data Exchange (ETDEWEB)
A general overview is provided of the Wind Energy Research and Development Program (WERD) structure, status, and current perspectives, and a highlight of recent achievements. The broad objectives of WERD are to: determine under what circumstances wind energy can make a viable contribution to Canadian energy supplies; establish the technology of wind energy conversion systems (WECS) to appropriate Canadian conditions; and to encourage and support Canadian industrial initiatives in the design and manufacture of WECS for both domestic and export markets. Field trials supported by WERD include: six small scale Savonius/Darrieus vertical axis wind turbines (VAWT) rated at 1 to 3 kW installed throughout Canada; a 37 kW VAWT mechanically coupled to a 50 kW diesel-electric set as part of a 100 kW remote community powerplant; five 50 kW grid-coupled VAWT generating systems; a 224 kW VAWT grid-coupled system in ...
1983-05-01
Wind turbine fault diagnosis based on Morlet wavelet transformation and Wigner-Ville distribution
Energy Technology Data Exchange (ETDEWEB)
Based on the Morlet wavelet transformation and Wigner-Ville distribution (WVD), we present a wind turbine fault diagnosis method in this paper. Wind turbine can be damaged by moisture absorption, fatigue, wind gusts or lightening strikes. Due to this reason, there is an increasing need to monitor the health of these structures. Vibration analysis is the best-known technology applied in wind turbine condition monitoring, in which the time-frequency analysis techniques such as Wigner-Ville distribution (WVD) are widely used. Theoretically WVD has an infinite resolution in time-frequency domain. For early wind turbine fault signals, however, there are two main difficulties in WVD analysis. One is strong noise signals in the background and the other is cross terms in WVD itself. In this paper, continuous wavelet transformation (CWT) is employed to filter useless noise in raw vibration ...
2010-12-15
Combined power generation with wind and ocean waves
Energy Technology Data Exchange (ETDEWEB)
It is often advantageous to generate power with combinations of wind and ocean waves. In fact ocean waves, their generation, propagation, dissipation are directly related to wind velocity and its duration oven the sea. In this paper an attempt has been made to demonstrate statistically to present some advantages with combined wind and ocean wave power generation. Even though many conceptual techniques and methods are possible to harness combined power generation, it is important to test feasibility of combined output as well as individual outputs mathematically. One of the major advantages of combined wind and wave power generation is to improve probability of continuous power supply (it minimises the interruptions and compensates power fluctuations with one another). Some of the major wave characteristics like wave Height (H), Time period (T), Wave length (L) significantly influence wave power ...
1996-09-01
Wind turbulence estimates in a valley by coherent Doppler lidar
British Library Electronic Table of Contents (United Kingdom)
Abstract In this paper, the effect of several turbulence parameters during various flow conditions in Owens Valley, educed from coherent Doppler lidar data have been studied. Radial velocity structure functions are processed to estimate the turbulent kinetic energy (TKE) dissipation rate, integral length scale and velocity variance, assuming a theoretical model for isotropic wind fields. Corrections for turbulence measurements have been considered to address the complications due to inherent volumetric averaging of radial velocity over each range gate, noise of the lidar data, and the assumptions required to estimate effects of smaller scales of motion on turbulence quantities. Using data from the Terrain-induced Rotor Experiment (T-REX) in April-May 2006, vertical profiles of wind and tur...
2011-01-01
Toward finding an optimal stockpile geometry to reduce dust emissions
Energy Technology Data Exchange (ETDEWEB)
Fugitive dust emissions from stockpiles in the open storage yards of industrial zones and the subsequent atmospheric dust dispersion have brought about many ecological and economical problems. This paper introduces a new approach to reduce pollutant emissions by simply changing pile configuration and without affecting the operational activity on these parks. Flow around piles of different geometries and for various wind conditions was studied using previously validated Computational Fluid Dynamic (CFD) simulations. Different pile height scenarios were investigated corresponding to a constant material volume and a fixed angle of repose under various wind magnitudes. The results obtained were integrated in order to evaluate the rate of dust emissions for the various configurations considered. It was found that, for the range of wind conditions and pile dimensions tested, an optimal geometry exists which corresponds to the ...
2006-07-01
TeV gamma-rays from the Northern sky pulsar wind nebulae
Energy Technology Data Exchange (ETDEWEB)
We estimate the TeV {gamma}-ray fluxes expected from the population of young pulsars in terms of the self-consistent time-dependent hadronic-leptonic model for the high-energy processes inside the pulsar wind nebulae (PWNe). This radiation model is based on the hypothesis of Arons and collaborators who postulate that leptons are accelerated inside the nebulae as a result of resonant scattering on heavy nuclei, which in turn are accelerated in the pulsar wind region or the pulsar inner magnetosphere. Our aim is to find out which PWNe on the northern hemisphere are the best candidates for detection at energies above 60 GeV and 200 GeV by the next generation of low-threshold Cherenkov telescopes.
2005-12-01
International Nuclear Information System (INIS)
A stratigraphic and geochemical study of alpine soils, which formed in later Pleistocene (late glacial) and Neoglacial deposits in the Wind River Mountains of western Wyoming, indicates that these soils are affected by air-fall in flux of inorganic pollutants. Arsenic, bromine and antimony appear to have been deposited in surface soils by incorporation of aeolian materials which were presumably transported by winds from industrial sources, including coal-burning operations. As vanadium was not found in surface soils at concentrations above site-specific background levels, oil-fired energy generating stations were not found to be significant sources of surface soil pollution in the region. Acid-rain effects were not observed in the soils. (author) 32 refs.; 2 figs.; 3 tabs.
1991-01-01
Start safety apparatus for internal combustion engine
Energy Technology Data Exchange (ETDEWEB)
A start safety apparatus of an engine adapted for a multipurpose power tool is described which consists of: an engine, an exciter coil generating alternate electromotive force in synchronism with rotation of the engine; an ignition coil having primary and secondary windings; a spark plug connected to the secondary winding of the ignition coil; a capacitor connected to the primary winding of the ignition coil the capacitor being charged with a positive half-cycle of the electromotive force; ignition timing control means for controlling discharge of the capacitor; a throttle control latch for setting a throttle valve of the engine in a predetermined throttle angle; a tool driven by the engine; and a centrifugal clutch transferring engine power to the tool when an engine speed exceeds a clutch-in speed.
1986-09-09
British Library Electronic Table of Contents (United Kingdom)
This paper uses multi-pass iteration particle swarm optimization (MIPSO) to solve short term hydroelectric generation scheduling of a power system with wind turbine generators. MIPSO is a new algorithm for solving nonlinear optimal scheduling problems. A new index called iteration best (IB) is incorporated into particle swarm optimization (PSO) to improve solution quality. The concept of multi-pass dynamic programming is applied to modify PSO further and improve computation efficiency.The feasible operational regions of the hydro units and pumped storage plants over the whole scheduling time range must be determined before applying MIPSO to the problem. Wind turbine power generation then shaves the power system load curves. Next, MIPSO calculates hydroelectric generation scheduling. It beg...
2008-01-01
Methods for probabilistic design of wind turbines
Energy Technology Data Exchange (ETDEWEB)
This report gives a brief introduction to the project `Probabilistic Design Tool for Wind Turbines` - PRODETO - which was carried out during the years 1996-98 with partial funding from the European Commission under the Non-Nuclear Energy Programme JOULE III. The report gives an overview of the objectives and motivation for the project, and the methodology used. In this context, an example of reliability-based wind turbine design against fatigue failure is outlined with emphasis on the various important steps herein, which include probabilistic load and resistance modelling, calculation of failure probability, and calibration of partial safety factors for use with a deterministic design code format. The results of the project are presented with emphasis on a developed computer program and its capabilities, and the various elements of an executed case study are outlined. A list of project reports concludes the report. (au)
1998-12-01
Federal Geothermal Research Program Update Fiscal Year 1999
Energy Technology Data Exchange (ETDEWEB)
The Department of Energy (DOE) and its predecessors have conducted research and development (R&D) in geothermal energy since 1971. To develop the technology needed to harness the Nation's vast geothermal resources, DOE's Office of Geothermal and Wind Technologies oversees a network of national laboratories, industrial contractors, universities, and their subcontractors. The following mission and goal statements guide the overall activities of the Office of Geothermal and Wind Technologies. This Federal Geothermal Program Research Update reviews the specific objectives, status, and accomplishments of DOE's Geothermal Program for Federal Fiscal Year (FY) 1999. The information contained in this Research Update illustrates how the mission and goals of the Office of Geothermal and Wind Technologies are reflected in each R&D activity. The Geothermal Program, from its guiding principles ...
2004-02-01
The effect of high lift airfoils on the cost effectiveness of HAWT and VAWT (horizontal and vertical axis wind turbine) machines is studied. The scope involved first studying modern two dimensional airfoils, and developing a generalized formulation for their performance in terms of lift, drag, and thickness at appropriate Reynolds numbers. Single element, multi-element, symmetrical, extra thick airfoils and jet flap airfoils were analyzed. The jet flap airfoils were considered to be unacceptable because of excessive power requirements. Then the effect of using the above airfoils on the rotors of a variety of wind turbines was made. Qualitative representation of the type of airfoils studied is given.
1979-05-01
Darrieus vertical axis wind turbine program overview
As a US Department of Energy (DOE) laboratory, Sandia Laboratories is developing Darrieus vertical axis wind turbine (VAWT) technology with the objective of encouraging private industry to produce economically feasible, commercially marketable wind energy systems. The first full cycle of development is essentially complete, and resulting current technology designs have been evaluated for cost-effectiveness. Aerodynamic, structural, and system analyses capabilities have evolved during this cycle to support and evaluate the system designs. This report presents some of the more salient recent developments, first generation costs, current activities, and future plans. Potential design improvements identified in the first development cycle are presented along with their cost benefits.
An investigation of the thermal performance of an oil filled transformer winding
Energy Technology Data Exchange (ETDEWEB)
Manufacturers may be required to design transformers to overload specifications. Oil viscosity changes and loss variation with temperature are not accounted for in the industry loading guide. A comprehensive test program was performed using a winding assembly with imbedded thermocouples. Steady state and transient tests were performed for natural and non-directed forced oil circulation. The temperature distribution in the winding was not linear with height as usually assumed. A large number of temperature sensors is required to determine the hot spot location. The location of the hot spot was found to be different and less predictable for natural oil circulation compared with non-directed forced oil circulation especially during overload conditions. This paper reports that improved loading guide equations were developed to account for oil viscosity, resistance change, cooling duct oil rise, and location of the hot spot.
1992-07-01
British Library Electronic Table of Contents (United Kingdom)
VHF wind-profiling radars often measure a decrease of echo power with zenith angle, which can be explained from in situ measurements of horizontal layering or anisotropy of metre-scale temperature structure in the atmosphere. There can also be an azimuthal variation of echo power, which is increased in an azimuth opposite to the vertical shear vector of horizontal wind. This paper checks if the azimuth variation can also be linked to in situ observations of temperature structure, using aircraft flights in the tropopause region near a VHF radar. At heights where VHF radar measures wind shear and aspect sensitivity, there can be an asymmetry in the probability distribution of horizontal gradient of potential temperature, for horizontal scale of e.g. hundreds of metres. The asymmetry is often...
2007-01-01
Aerial dispersal plasticity under different wind velocities in a salt marsh wolf spider
British Library Electronic Table of Contents (United Kingdom)
Dispersal can be regarded as a process operating both between and within patches of suitable habitat. For uncontrolled dispersal processes, the risk of crossing the borders of the habitat patch and arriving in the unsuitable landscape matrix will increase with decreasing patch area, in particular when the distance between isolated habitat patches is larger than the species' average dispersal capacity. Ballooning dispersal in spiders can be considered as a passive dispersal process, in which dispersed distances depend on the prevalent wind velocity. We executed a reaction norm analysis to analyze how dispersal propensity of the salt marsh wolf spider Pardosa purbeckensis depended on population characteristics (patch size) and the environment (wind velocity). Dispersal propensity was affecte...
2007-01-01
Energy Technology Data Exchange (ETDEWEB)
A three dimensional sea-land breeze model and lagrangian particle dispersion model have been employed for the study on the mesoscale atmospheric dispersion of radioactive materials released from Wolsung NPPs. In this study, atmospheric dispersion simulations are carried out under two synoptic weather conditions: the geostrophic flow is a weak northerly wind (CASE 1) and a strong northerly wind (CASE 2) on a clear day in spring. The results show that atmospheric dispersion is affected by sea-land breeze and the recirculation of particles by the change of wind direction between sea breeze and land breeze plays an important role in atmospheric concentration distribution of radioactive materials.
1997-12-01
Techno-economic assessment of anaerobic digestion systems for agri-food wastes
Energy Technology Data Exchange (ETDEWEB)
Activities in British Columbia's Fraser Valley generate an estimated 3 million tones of agriculture and food wastes annually, of which 85 per cent are readily available for anaerobic digestion. The potential for energy generation from biogas through anaerobic digestion is approximately 30 MW. On-farm manure-based systems represent the most likely scenario for the development of anaerobic digestion in British Columbia in the near future. Off-farm food processing wastes may be an alternative option to large centralized industrial complexes. Odour control, pathogen reduction, improved water quality, reduced greenhouse gas emissions and reduced landfill usage are among the environmental benefits of anaerobic digestion. The economical benefits include power and heat generation, biogas upgrading, and further processing of the residues to produce compost or animal bedding. This paper described a newly developed anaerobic digestion (AD) ...
2010-07-01
Bioaccumulation of trace metals in farmed fish from South China and potential risk assessment
British Library Electronic Table of Contents (United Kingdom)
Concentrations of trace metals were determined in water, sediment, fish feed and two species of farmed fish, pompano and snapper, collected from Daya Bay and Hailing Bay of South China in July 2007 and January 2008. Total average concentrations of Cu, Pb, Zn, Cd, Cr, Hg and As were 1.6, 2.7, 27.3, 0.025, 0.62, 0.18 and 0.59?g/gdrywt in pompano and 1.5, 2.6, 23.6, 0.020, 0.55, 0.22 and 0.53?g/gdrywt in snapper. In general, the concentrations of all target metals except Hg were positively correlated with lipid contents whereas negative correlations were observed between the metal concentrations and fish body weights. Model calculation indicated that dietary uptake of Zn and Cd predominate their accumulation in snapper, accounting for 99.9% and 98.2% of the total inputs. Risk ...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
This report made for the Swiss Federal Office of Energy (SFOE) discusses the conception, planning and construction of an easy-to-operate pilot heating plant that uses chicken litter as its fuel. The plant, which is installed at a chicken farm in Boesingen, Switzerland, produces 250 - 350 kW and not only supplies heat for two chicken sheds and two households, but also provides energy for a drying plant in summer. The results of measurements made on emissions are discussed and, within the framework of an eco-balance analysis, comparisons are made between the direct use of the droppings as manure or as a fuel. The cost-effectiveness of the plant is examined and the influence of plant size and other factors discussed. Further, legal questions concerning the use of chicken litter as a fuel for heating installations are discussed; the use of the droppings as a fuel is not foreseen in the legislation concerning water protection and airborne emissions of pollutants. ...
2001-07-01
Utilization of wastes from coal-fired power plants for soil improvement and plant nutrition
International Nuclear Information System (INIS)
The reduction of emission from power plants of the public power industry inevitably leads to more and more residual products being obtained which require utilization. Traditionally, the building and building materials industry as well as, for a number of years, the gypsum industry have been the main customers processing these residual materials. To avoid having to tip them at landfills that are in short supply already, further uses are sought; so, for instance, in farming to ameliorate soil and fertilize plants. Relative to this subject, proposals are already available which are presented as lectures at the conference and discussed, together with practical knowledge and new investigation results. (BBR).
1991-10-08
The effect of high voltage transmission lines on agricultural land values in minnesota
Energy Technology Data Exchange (ETDEWEB)
Overhead, high power transmission lines have secured rights of way on agricultural lands in Minnesota. The economic impact of such utility crossings, including effects on land price, was investigated. Sale records and survey data were analyzed. Buyers, sellers, and brokers were interviewed concerning inconvenience, radio interference, appearance, and loss of irrigation possibilities due to the transmission lines. In nine affected sales, there was only one case in which less money was indicated for the farm because of the presence of a transmission line.
1981-04-01
The effect of high voltage transmission lines on agricultural land values in Minnesota
Energy Technology Data Exchange (ETDEWEB)
Overhead, high power transmission lines have secured rights of way on agricultural lands in Minnesota. The economic impact of such utility crossings, including effects on land price, was investigated. Sale records and survey data were analyzed. Buyers, sellers, and brokers were interviewed concerning inconvenience, radio interference, appearance, and loss of irrigation possibilities due to the transmission lines. In nine affected sales, there was only one case in which less money was indicated for the farm because of the presence of a transmission line.
1981-04-01
Energy Technology Data Exchange (ETDEWEB)
The Waste Acceptance Preliminary Specifications (WAPS) require that the DWPF estimate the inventory of long-lived radionuclides present in the waste glass, and report the values in the Waste Form Qualification Report. In this report, conservative (biased high) estimates of the radionuclide inventory of glass produced from waste currently in the Tank Farm are provided. In most cases, these calculated values compare favorably with actual data. In those cases where the agreement is not good, the values reported here are conservative.
1993-02-04
Poultry Production | Ag 101 | Agriculture | US EPA
... Poultry Production | Ag 101 | Agriculture | US EPA Ag 101 provides a brief overview of poultry production in the U.S.... Poultry Production Jump to main content. Ag 101 Contact Us Search: All EPA This Area You are here: EPA Home Agriculture ...Ag 101 Poultry Production Poultry Production Poultry production is an important and diverse component of American agriculture. Poultry products including eggs, chicken and turkey meat are ... In 1997, nearly 99,700 farms were producing poultry and poultry products (egg, broiler, and turkey; NASS/USDA). While broiler chicken ...
Natural gas use in Saskatchewan hog industry
Energy Technology Data Exchange (ETDEWEB)
A study was conducted to examine the energy consumption in existing and new hog farming facilities and to analyse the potential for increased natural gas use in the Saskatchewan hog industry. Existing heating/cooling, ventilation and feed mill equipment choices offer possibilities for running on electricity, natural gas or propane. Energy costs are lowest when natural gas is used. To put the study in context, an overview of the Saskatchewan hog industry was provided. The potential increase in natural gas use in hog production by year 2005 was estimated. 10 refs., 6 tabs., 8 figs.
1996-11-01
Energy Technology Data Exchange (ETDEWEB)
This article outlines the use of gasifiers during World War II and how, with soaring fuel prices, producer gas may provide an alternate energy path for agribusiness and farms today. In the last few years, the University of California has become a focus of producer gas research in the US. Biomass fuels used include crushed walnut shells, fruit pits, cereal straw and corn cobs. Particle size, moisture content and slagging create problems and the right kind of gas producer must be used to obtain reliable conversion to producer gas.
1980-09-08
Fluidized-bed energy technology for biomass conversion
Fluidized bed technology was experimentally evaluated for the combustion and gasification of cotton gin waste. The isothermal bed temperatures in the reactors could be maintained below the ash fusion point of the waste. Raw stripper harvested cotton gin trash could be metered directly into the fluidized-bed reactors indicating that little feed preparation is required. H and CO were the primary products of gasification, and approximately 3200-400 Btu of gas were produced per lb of cotton gin waste. These techniques offer the potential of providing small-scale energy conversion systems for use on farms.
1980-01-01
Energy production on farms. Sustainability of energy crops
International Nuclear Information System (INIS)
In this article the results of a study on sustainability of energy crops are discussed. Contribution to the reduction of the greenhouse effect and other environmental effects were investigated for the Netherlands. The study assumed that energy crops are grown on set-aside land or grain land. Generating electricity and/or heat from hemp, reed, miscanthus, poplar and willow show the best prospects. These crops are sustainable and may in the future be economically feasible. Ethanol from winter wheat shows the most favourable environmental effects, but is not economically efficient. Liquid fuels from oil seed rape and sugar beet are not very sustainable. 2 tabs., 4 refs.
1994-12-06
Deploying anaerobic digesters: Current status and future possibilities
Energy Technology Data Exchange (ETDEWEB)
Unmanaged pollutants from putrescible farm, industrial, and municipal wastes degrade in the environment, and methane emitted from their decomposition may contribute to global climate change. Under modern environmental regulations, these wastes are becoming difficult to dispose of using traditional means. One waste management system, anaerobic digestion or AD, not only provides pollution prevention but can also convert a disposal problem into a new profit center. This report is drawn from a special session of the Second Biomass Conference of the Americas. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
1996-01-01
Computer Simulation of Factors Affecting Rural Education.
Computer simulations of agricultural finance and management may be helpful to students preparing for agricultural careers. Simulations would provide problem definition and problem solving in realistic interactions with complex and ambiguous situations similar to those encountered in farming. The paper describes a major financial problem for farmers, explores the implications of that problem for students, and outlines a computer-based simulation model which would give students experience in dealing with the problem. Data sources for simulations, potentials of interactive exercises among students, and advantages of using real data with existing ambiguities are described. The board game "AGRICULTURE" is discussed as a prototype for simulation. (LFL)
1986-02-01
A PDA-Based ECG Beat Detector for Home Cardiac Care.
Recent rapid growth in mobile computing technologies enables telemedicine applications to operate on mobile devices. Our focus is on the design of an integrated electrocardiogram (ECG) beat detector on a Personal Digital Assistant (PDA) platform for the health screening process. The ECG beat detector module will be supported by the PDA version of Personal Health Information Management System (PHIMS) and Facilitated Accurate Referral Management System (FARMS) through wireless network infrastructure as a home-based mobile cardiac monitoring solution. PMID:17282192
2005-01-01
Wind for Schools (Presentation)
Energy Technology Data Exchange (ETDEWEB)
Schools are key to achieving the goal of producing 20% of the nation's electricity demand. Most significantly, schools are training the scientists, technicians, businesspeople, decisionmakers, and teachers of the future. What students learn and believe about wind energy will impact the United States' ability to create markets and policy, develop and improve technology, finance and implement projects, and create change in all of our public and private institutions. In the nearer term, school districts have large facility costs, electrical loads, and utility costs. They are always in search of ways to reduce costs or obtain revenue to improve educational programs. Schools value teaching about the science and technology of renewable energy. They are important opinion leaders, particularly in rural communities. And their financial structures are quite different from other institutions (funding, incentives, restrictions, etc.). Learning objectives: The ...
2007-06-01
Transport of a power plant tracer plume over Grand Canyon National Park
Energy Technology Data Exchange (ETDEWEB)
Meteorological and air-quality data, as well as surface tracer concentration values, were collected during 1990 to assess the impact of Navajo Generating Station (NGS) emissions on Grand Canyon National Park (GCNP) air quality. These data have been used in the present investigation to determine between direct and indirect transport routes taken by the NGS plume to produce measured high-tracer concentration events at GCNP. Results show that complex-terrain features affect local wind-flow patterns during winter in the Grand Canyon area. Local channelling, decoupled canyon winds, and slope and valley flows dominate in the region when synoptic systems are weak. Direct NGS plume transport to GCNP occurs with northeasterly plume-height winds, while indirect transport to the park is caused by wind direction shifts associated with passing synoptic systems. Calculated polluted airmass positions along the modeled ...
1999-08-01
The commercial potential of the 17 m, 100 kW Darrieus Vertical Axis Wind Turbine (VAWT) is discussed. Long term testing is in progress. As the first commercially adapted Darrieus turbines built by DOE, the superior cost, structural integrity, and output characteristics demonstrated by the prototypes appear particularly promising.
1981-01-01
International Nuclear Information System (INIS)
This paper presents the directional dependence of surface scaling parameters namely roughness length and corresponding friction velocity, for neutral category of Tarapur coastal site. The average roughness length of lowest value of 0.07 m (SW) and the highest value of 0.32 m (E) and average friction velocity of lowest value 1.6 m/sec(SSE) and a highest value 2.8 m/sec (SW) for the year 2006 were observed. Wind profile studies for the coastal site Tarapur with the wind data measured from meteorological tower of 30m which is at 1500m downwind fetch distance from the coastal line in the east direction gave the wind profile index parameter 'p' as 0.4, 0.5 and 0.75 for Unstable, Neutral and Stable weather conditions respectively. Sector Average Turbulent kinetic energy estimated as 17.7m2/s2 and its dissipation rate is 3.1 m2/s3 for the 10m elevation from the surface. A surface drag coefficient CD for the 10m height is 0.0076 ...
2007-06-05
Energy Technology Data Exchange (ETDEWEB)
This paper uses multi-pass iteration particle swarm optimization (MIPSO) to solve short term hydroelectric generation scheduling of a power system with wind turbine generators. MIPSO is a new algorithm for solving nonlinear optimal scheduling problems. A new index called iteration best (IB) is incorporated into particle swarm optimization (PSO) to improve solution quality. The concept of multi-pass dynamic programming is applied to modify PSO further and improve computation efficiency. The feasible operational regions of the hydro units and pumped storage plants over the whole scheduling time range must be determined before applying MIPSO to the problem. Wind turbine power generation then shaves the power system load curves. Next, MIPSO calculates hydroelectric generation scheduling. It begins with a coarse time stage and searching space and refines the time interval between two time stages and the search spacing pass by pass (iteration). With ...
2008-04-15
Repowering needs its own rules; Repowering braucht eigene Regeln
Energy Technology Data Exchange (ETDEWEB)
Less wind power plants in the landscape, more power from renewables, less carbon dioxide and higher tax: The advantages of repowering for communities are considerable. Still, they are hesitant to use it. (orig.)
2007-08-27
Power from the islands; Strom von den Inseln
Energy Technology Data Exchange (ETDEWEB)
The picture of wind energy parks at the German North Sea Coast is well-known. There are also some of them on the Northern Friesian Islands. Recently, however, biogas plants have been conquering the western coast of Schleswig-Holstein, starting from the continent.
2007-08-15
million for advanced energy projects Thu, Sep 29, 2011 - Project Aims to Bring Bio-based Jet Fuel Production to the Northwest Mon, Sep 12, 2011 - Drive like the wind Thu, Aug 25,...
2011-10-09
Energy Technology Data Exchange (ETDEWEB)
This review covers research done at Lawrence Livermore National Laboratory under DOE contract. Areas of research are as follows: star evolution supernovae, and nucleosynthesis; stellar atmospheres and winds; galaxies and interstellar space; and high-energy astrophysics.
1983-01-01
Energy Technology Data Exchange (ETDEWEB)
This review covers research done at Lawrence Livermore National Laboratory in the fields of astronomy and astrophysics. The research areas mentioned are as follows: star evolution, supernovae, and nucleosynthesis; stellar atmospheres and winds; galaxies and the interstellar medium; and high-energy astrophysics.
1984-01-01
Jul 8, 2008 ... This case involves the flow over the ONERA M6 wing. ... The wind tunnel tests are documented by Schmitt and Charpin in the AGARD Report AR-138 ... supersonic flow, shocks, and turbulent boundary layers separation). ...
NASA's capabilities in advanced energy research and development
International Nuclear Information System (INIS)
A 2007 report compiled by members of the armed services indicates that climate change presents a serious security threat to the American public as well as to United States military operations. It is likely that climate change will increase global tensions and competition for resources. This presentation discussed advanced research and technology programs conducted by the National Aeronautics and Space Administration (NASA). Scientists and engineers at NASA have developed a number of technologies that may contribute to American energy security. Advanced energy research and development programs initiated by the organization include advanced heat engines; wind turbines; batteries and electric cars; solar photovoltaics; and fuel cell technologies. NASA's aeronautics and space exploration program has several capabilities relevant to advanced wind power systems. A collaborative program is currently underway to develop airborne ...
2010-02-22
Millions of battery stores; Millionen kleine Speicher
Energy Technology Data Exchange (ETDEWEB)
It is still a vision at the time being, but wind power and electric cars may complement each other efficiently: Batteries are charged when the power demand of the grid has been saturated. In case of sudden demand peaks, the stored power is transmitted back into the grid. (orig.)
2007-07-15
JPL Air Sea Interaction & Climate Team - Data
provides global ocean-surface wind fields with more structures than numerical weather prediction (Geophys. Res. Lett., Vol 25, No. 6, 761-764). The NSCAT data sets was produced...
2011-08-26
Increased wind-up to heat pain in women with a childhood history of functional abdominal pain
UK PubMed Central (United Kingdom)
Idiopathic or functional abdominal pain (FAP) is common in school-age children and typically reflects a functional gastrointestinal disorder (FGID). FGIDs in adults have been distinguished by...Full Text Available
2011-04-01
Improved double-multiple streamtube model for the Darrieus-type vertical-axis wind turbine
Energy Technology Data Exchange (ETDEWEB)
Double streamtube codes model the curved blade (Darrieus-type) vertical-axis wind turbine (VAWT) as a double actuator-disk arrangement (one disk for the upwind half of the rotor and a second disk for the downwind half) and use conservation of momentum principles to determine the forces acting on the turbine blades and the turbine performance. These models differentiate between the upwind and downwind sections of the rotor and are capable of determining blade loading more accurately than the widely-used single-actuator-disk streamtube models. Additional accuracy may be obtained by representing the turbine as a collection of several streamtubes, each of which is modeled as a double actuator disk. This is referred to as the double-multiple-streamtube model. Sandia National Laboratories has developed a double-multiple streamtube model for the VAWT which incorporates the effects of the incident wind boundary layer, nonuniform velocity between the ...
1983-01-01
Energy Technology Data Exchange (ETDEWEB)
IMO Momentenlager GmbH of Gremsdorf near Nuremberg produces large rotary bearings for ENERCON wind power systems, preferably for the E-70 and E-82 generators. (orig.)
2007-07-01
Energy Technology Data Exchange (ETDEWEB)
A 19.1 metre wind turbine blade was subjected to static tests. The purpose of the test series was to verify the abilities of different types of sensors to detect damage in wind turbine blades. Prior to each of the static test-series an artificial damage was made on the blade. The damage made for each test-series was surveyed during each series by acoustic emission, fiber optic micro bend displacement transducers and strain gauges. The propagation of the damage was determined by use of ultra sonic and X-ray surveillance during stops in the test series. By use of acoustic emission it was possible to measure damage propagation before the propagation was of visible size. By use of fiber optic micro bend displacement transducers and strain gauges it was possible to measure minor damage propagation. By use of both ultra sonic, and X-ray NDT-equipment it were possible to determine the size of propagated damage. (au)
2002-05-01
Changes in Sea-Level Pressure over South Korea Associated with High-Speed Solar Wind Events
We explore a possibility that the daily sea-level pressure (SLP) over South Korea responds to the high-speed solar wind event. This is of interest in two aspects: First, if there is a statistical association this can be another piece of evidence showing that various meteorological observables indeed respond to variations in the interplanetary environment. Second, this can be a very crucial observational constraint since most models proposed so far are expected to preferentially work in higher latitude regions than the low latitude region studied here. We have examined daily solar wind speed ${\\rm V}$, daily SLP difference ${\\rm \\Delta SLP}$, and daily ${\\rm \\log(BV^{2})}$ using the superposed epoch analysis in which the key date is set such that the daily solar wind speed exceeds 800 ${\\rm kms^{-1}}$. We find that the daily ${\\rm \\Delta SLP}$ averaged out of 12 events reaches its peak at day +1 and gradually ...
2011-01-01
Blowing in the Wind: Unanchored Patient Information Work during Cancer Care
UK PubMed Central (United Kingdom)
Patients do considerable information work. Technologies that help patients manage health information so they can play active roles in their health-care, such as personal health records, provide...Full Text Available
2010-01-01
Bathymetry and temperature of some glacial lakes in Wyoming
UK PubMed Central (United Kingdom)
On the west flank of the Wind River Mountains, Wyoming, are several large lakes occupying glacially scoured depressions dammed by terminal moraines. Fremont, Willow, and New Fork Lakes, having maximal...Full Text Available
1980-04-01
Automatic-Control System for the 17-Metre Vertical-Axis Wind Turbine (VAWT).
The 17-metre DOE/Sandia VAWT began operation in March 1977. Since that time the turbine has been operated strictly by manual control for the purpose of data acquisition and performance analysis; this procedure has limited the VAWT operation time and power...
1980-01-01
Aerodynamic Force Characteristics of Bluff Bodies.
The lift and drag characteristics of a wide range of bluff body shapes were studied using data from sources including wind tunnel testing and flow visualization. For a given orientation of any body, it is found that its drag is strongly influenced by its ...
1985-01-01
United States Air Force Academy (USAFA) Vertical Axis Wind Turbine. Final report May 77-Sep 80
This report describes the design, fabrication, installation and testing of a small variable-speed vertical axis wind turbine (VAWT). This VAWT is unique in its installation using hand tools only; unconventional and simple support system; and variable speed operation under microprocessor control. Initial testing confirmed that the turbine can be controlled by commanded alternator field modulation. Further studies will be directed toward determination of an optimum control algorithm.
1980-09-01
Three pitch control systems for vertical axis wind turbines compared
Energy Technology Data Exchange (ETDEWEB)
The desirable performance attributes of a vertical axis wind turbine (VAWT) include high starting torque, high peak efficiency, broad operating range and a reasonable insensitivity to the parameters that define its operation. The theoretical performance of three variable pitch mechanisms for VAWT are compared. Cycloturbines use cam devices or gears to impose a sinusoidal pitch regime. In the mass-stabilised system, pitch is determined by the interplay of two opposing moments on the blades. These two mechanisms are compared with Aeropitch, a hypothetical pitch control system in which stabilising moments are related to the blade relative velocity. (Author)
1992-01-01
On Witten's instability and winding tachyons
Energy Technology Data Exchange (ETDEWEB)
We investigate, from a spacetime perspective, some aspects of Horowitz's recent conjecture that black strings may catalyze the decay of Kaluza-Klein spacetimes into a bubble of nothing. We identify classical configurations that interpolate between flat space and the bubble, and discuss the energetics of the transition. We investigate the effects of winding tachyons on the size and shape of the barrier and find no evidence at large compactification radius that tachyons enhance the tunneling rate. For the interesting radii, of order the string scale, the question is difficult to answer due to the failure of the {alpha}' expansion.
2006-12-15
JOINT PROBABILITIES FOE ENVIRONMENTAL LOADS (OCE 90)
Environmental Research Database
ObjectivesObjectives Not AvailableDescriptionThis proposal seeks to extend what is currently the most comprehensive offshore environmental data collection programme at a platform on the UKGS involving continuous collection of wave height and direction, wind speed and direction, current and wave particle kinematics. Data has been collected with this system since 1994 and the proposal is to extend this until 1999 thus providing an extensive set of storm data collected at 5Hz which will allow examination of the joint behaviour of wave, wind [continued...
1998-01-16
Investigation of Various Wind Turbine Drivetrain Condition Monitoring Techniques
Energy Technology Data Exchange (ETDEWEB)
The wind industry has experienced premature turbine component failures during the past years. With the increase in turbine size, these failures, especially those found in the major drivetrain components, i.e. main shaft, gearbox, and generator, have become extremely costly. Given that the gearbox is the most costly component in the drivetrain to fix, the National Renewable Energy Laboratory (NREL) initiated the Gearbox Reliability Collaborative (GRC) to determine the causes for premature gearbox failures and subsequently, recommend improvements to gearbox design, manufacture, and operational practices. The GRC has two identical test gearboxes, which are planned for a dynamometer and a field test, respectively.
2010-08-01
Inland penetration of sea breeze around Wolsung NPP site
Energy Technology Data Exchange (ETDEWEB)
A three dimensional sea-land breeze model has been employed for the study on the inland penetration of sea breeze around Wolsung NPP site. In this study, the sea breeze simulation was carried out under the weak northwesterly geostrophic wind (3.2 m/s, 339 .deg.) at 850 hPa in Spring. The results showed that sea breezes developed near Wolsung site penetrated into about 20 km inland under the weak northwesterly geostrophic wind in Spring. This result agreed with observation data around Wolsung site on May 1996.
1997-07-01
Inland penetration of sea breeze around Wolsung NPP site
International Nuclear Information System (INIS)
A three dimensional sea-land breeze model has been employed for the study on the inland penetration of sea breeze around Wolsung NPP site. In this study, the sea breeze simulation was carried out under the weak northwesterly geostrophic wind (3.2 m/s, 339 .deg.) at 850 hPa in Spring. The results showed that sea breezes developed near Wolsung site penetrated into about 20 km inland under the weak northwesterly geostrophic wind in Spring. This result agreed with observation data around Wolsung site on May 1996.
1997-11-06
High altitude wind velocity at San Pedro Martir and Mauna Kea
We analyze the monthly average wind velocity at about 12 km above sea level, between 1980 to 1995, for San Pedro Martir, Mauna Kea, another existing observatorie and some sites of interest. We compare the results obtained from two different data sets, the GGUAS and NCEP. Our results show that San Pedro Martir and Mauna Kea are comparable and are amongst the most suitable sites to apply slow wavefront corrugation correction techniques
2003-01-01
Energy Technology Data Exchange (ETDEWEB)
This annex provides a description of the sensor schemes and the non-destructive testing (NDT) methods that have been investigated in this project. Acoustic emission and fibre optic sensors are described in some detail whereas only the key features of well-established NDT methods are presented. Estimates of the cost of different sensor systems are given and the advantages and disadvantages of the different schemes is discussed. (au)
2002-05-01
Dynamic analysis of Darrieus vertical axis wind turbine rotors
The dynamic response characteristics of the vertical axis wind turbine (VAWT) rotor are important factors governing the safety and fatigue life of VAWT systems. The principal problems are the determination of critical rotor speeds (resonances) and the assessment of forced vibration response amplitudes. The solution to these problems is complicated by centrifugal and Coriolis effects which can have substantial influence on rotor resonant frequencies and mode shapes. The primary tools now in use for rotor analysis are described and discussed. These tools include a lumped spring mass model (VAWTDYN) and also finite-element based approaches. The accuracy and completeness of current capabilities are also discussed.
1981-05-01
Design, performance, and economics of 50-kW and 500-kW vertical axis wind turbines
A review of the development and performance of the DAF Indal 50-kW vertical axis Darrieus wind turbine shows that a high level of technical development and reliability has been achieved. Features of the drive train, braking and control systems are discussed and performance details are presented. Details are also presented of a 500-kW VAWT that is currently in production. A discussion of the economics of both the 50-kW and 500-kW VAWTs is included, showing the effects of charge rate, installed cost, operating cost, performance, and efficiency. 6 references.
1983-11-01
A preliminary account of wind speed data in the coastal regions of Bangladesh
Energy Technology Data Exchange (ETDEWEB)
A wind energy study (WEST) in the coastal region of Bangladesh has been undertaken, in collaboration with Local Government Engineering Department (LGED) and with technical support of the UK`s Energy Technology Support Unit (ETSU) under an ODA programme. Seven 25m high masts have just been installed at selected places and data for a complete year will be recorded. A brief account of the mast erection is given and some preliminary data is presented. Results indicate that fresh data is going to give higher figures than the meteorological ones. (author)
1997-06-01
Energy Technology Data Exchange (ETDEWEB)
The windmill industry in Denmark is currently confronted with making a choice between competing technologies so that the role of the stimulus of state subsidies for research has lately increased in importance. The Ministry of Energy, it is claimed, must be aware of this as possibilities for making use of research results are dictated by the market and competition. The industry is not sympathetic to the idea of state research contracts with specified goals for which manufacturers must produce a technical solution. Consultancy firms should work towards solving general problems which could help the industry as a whole. Wind turbines which are cheap to produce and operate are of more interest to industry than those which are technologically advanced or of a lighter construction. It is not thought to be advantageous to concentrate the allocation of subsidies on one key project chosen by the Ministry itself, such as the current intense interest in turbine blades. ...
1995-10-01
International Nuclear Information System (INIS)
The windmill industry in Denmark is currently confronted with making a choice between competing technologies so that the role of the stimulus of state subsidies for research has lately increased in importance. The Ministry of Energy, it is claimed, must be aware of this as possibilities for making use of research results are dictated by the market and competition. The industry is not sympathetic to the idea of state research contracts with specified goals for which manufacturers must produce a technical solution. Consultancy firms should work towards solving general problems which could help the industry as a whole. Wind turbines which are cheap to produce and operate are of more interest to industry than those which are technologically advanced or of a lighter construction. It is not thought to be advantageous to concentrate the allocation of subsidies on one key project chosen by the Ministry itself, such as the current intense interest in turbine blades. ...
Energy Technology Data Exchange (ETDEWEB)
The Archean core of the Laramide Wind River uplift records evidence of at least three major granitoid-forming episodes. The oldest, the Dry Creek gneiss (DCG), was emplaced by 2.8 Ga and occupies the northeastern part of the range. Mafic, pelitic and ultramafic inclusions occur in the DCG. Elsewhere in the Wind River Mountains there is evidence for crustal components as old as 3.8 Ga. The Bridger batholith (BB), intruded at 2.67 Ga, is found in the west-central Wind River Mountains. The Wind River batholith (WRB) refers to the youngest Late Archean granodiorites and granites which are found throughout the range and includes granitoids previously name the Louis Lake, Bears Ears, Popo Agie, and Middle Mountain intrusions. Although granitoids of the Wind River batholith have been dated at 2.63 and 2.55 Ga, they are considered together here because there is a complete gradation in rock ...
1992-01-01
Field investigation of a wake structure downwind of a VAWT in a windfarm array
Energy Technology Data Exchange (ETDEWEB)
The effects of upwind turbine wakes on the performance of a FloWind 17-m VAWT were investigated through a series of field experiments conducted at the FloWind windfarm on Cameron Ridge, Tehachapi, California. The field experiment was conducted within a VAWT array consisting of more than nine VAWTs with separations 3D crosswised by 8D downwind (where D is the turbine diameter) in a staggered configuration. The array is the upwind three rows of VAWTS in a total of six rows that are on top of the Cameron Ridge plateau. The terrain features in the vicinity are reasonably regular, with an upslope of 7 deg on the average; however, several local irregularities are present. The annual hourly averaged wind speed exceeds 8 m/s at the site. The wind field and the power-outputs of nine turbines within the array were measured with wind sensors and power transducers. Nine Gill propeller and 18 ...
1987-10-01
International Nuclear Information System (INIS)
Wind tunnel tests were performed of three fugitive dust control agents derived from potato and sugar beet products. These materials are being considered for use as dust suppressants to reduce the potential for transport of radioactive materials by wind from radioactive waste construction and remediation sites. Soil and dust control agent type, solution concentrations, application quantities, aging (or drying) conditions, surface disturbance, and wind and saltating sand eolian erosive stresses were selected and controlled to simulate application and exposure of excavated soil surfaces in the field. A description of the tests, results, conclusions, and recommendations are presented in this report. The results of this study indicate that all three dust control agents can protect exposed soil surfaces from extreme eolian stresses. It is also clear that the interaction and performance of each agent with various soil types may ...
1993-01-01
Use of numerical wind-wave models for assessment of the offshore wave energy resource
Energy Technology Data Exchange (ETDEWEB)
In the last two decades the performance of numerical wind-wave models has improved considerably. Several models have been routinely producing good quality wave estimates globally since the mid-1980s. The verifications of wind-wave models have mainly focused on the evaluation of the error of the significant wave height H{sub s} estimates. However, for wave energy purposes, the main parameters to be assessed are the wave power P{sub w} and the mean (energy) period T{sub e}. Since P{sub w} is proportional to H{sub s}{sup 2}T{sub e}, its expected error is much larger than for the single-wave parameters. This paper summarizes the intercomparison of two wind-wave models against buoy data in the North Atlantic and the Mediterranean Sea to select the most suitable one for the construction of an Atlas of the wave energy resource in European waters. A full verification in the two basins of the selected model--the WAM model, ...
1997-08-01
Energy Technology Data Exchange (ETDEWEB)
As an alternative to the usual way of installing wind machines in extended windfarms new concepts are being developed. Several wind turbines are affixed to one support structure and can be aligned together. Drafts of steel constructions developed by students in three diploma theses are presented. The attempt to transform existing design standards requires extensive discussion of possible influence scenarios. Several concepts regarding structure and safety elements are described and evaluated. The design of the support structure is to be seen as a first step to the practicability of the whole concept. A preliminary mass calculation and a specification of further cost factors facilitates the comparison to conventional wind power stations. (orig.) [Deutsch] Als Alternative zur ueblichen Praxis, Windenergieanlagen in Form grossflaechiger Windparks zu bauen, werden Konzepte entwickelt, bei denen mehrere Konverter an einem ...
1996-06-01
Environmental data for sites in the National Solar Data Network
Energy Technology Data Exchange (ETDEWEB)
The Detartment of Energy's National Solar Data Program established solar energy systems in residential and commercial buildings across the United States. These solar sites are linked to Vitro Laboratories Division's computer in the National Solar Data Network (NSDN). Vitro collects and analyzes data from this network to determine the thermal performance of each of the solar systems. Environmental information collected at the sites for the month of August 1980 is presented. The environmental data for the NSDN are presented in the form of tables for each solar site. The solar sites are grouped into 12 zones, each of which consists of several adjacent states. The solar energy sites are in alphabetical sequence within each zone. The tables provide available meteorological data for reporting sites in the NSDN as follows: (1) Insolation: the insolation table presents the total, diffuse, direct, maximum, and extra-terrestrial radiation for the solar site. It also shows the ...
1980-08-01
Energy Technology Data Exchange (ETDEWEB)
In the past, Condition Monitoring Systems (CMS) still showed weaknesses during the employment in the damage diagnosis and/or early failure detection of damages of roller bearings in transmissions of wind power plants. This is not only due to the insufficient consideration of the variable frequency of the wind power plants during the internal processing. The presently used methods of analysis result from the communication technology and are used successfully for years at frequency solid systems. Usually, only too few information are at the disposal to the supplier of CMS in order to parametrize their systems on the respective application particularly. An exact knowledge of the internal structure of the object to be diagnosed is compellingly necessary for a successful diagnosis so that a loadable statement based on the acquired measuring data base becomes possible. Furthermore, one must clarify the borders of the presently used systems. The ...
2010-07-01
Depositional history of the Lower Triassic Dinwoody Formation in the Wind River basin area, Wyoming
Energy Technology Data Exchange (ETDEWEB)
Thirty-three measured sections of the Dinwoody Formation, including five from the literature, provide information on thickness, lithology, paleontology, and stratigraphic relations within the Wind River basin and immediately adjacent areas of Wyoming. Most of these sections are in Fremont County, and some lie within the Wind River Indian Reservation. The Dinwoody becomes progressively thinner eastward, from a maximum thickness of 54.6 m in the northwestern Wind River Mountains to zero near the Natrona County line. The formation is characterized by yellowish-weathering, gray siltstone and silty shale. Variable amounts of limestone, sandstone, gypsum, and claystone are also present. Marine bivalves, gastropods, brachiopods (Lingula), and conodonts are common in the western part of the study area, but are absent to the northeast in gypsiferous strata, and near the eastern limit of Dinwoody deposition. The Dinwoody in the ...
1993-04-01
CWTC business plan; Wind turbine component centre
Energy Technology Data Exchange (ETDEWEB)
This report presents the Business Plan for the establishment of the Wind Turbine Component Centre (CWTC) to meet the objectives of performing theoretical research and experimental testing. The core idea of a CWTC is to support the Danish wind energy industry and research activities at the component level improving the competitive advantage of that industry. The CWTC will in itself operate its activities, including access to test and experimental facilities, on a semi commercial basis. The business model for the CWTC presented is based on revenues coming from component manufacturers as well as research grants, and will include membership fees as well as hourly payment and larger projects where payment is a limited project sum. The presented roadmap model clarifies the development path towards a fully developed CWTC, which will cover test of all important components along the drive-train as well as offering a comprehensive systematic ...
2011-04-15
X-ray, Optical, and Radio Observations of SN 1999em and SN 1998S
Observations of the Type II-P (plateau) Supernova (SN) 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first and only Type II-P detected at both X-ray and radio wavelengths. It is the least radio luminous and one of the least X-ray luminous SN ever detected (except for the unusual and very close SN 1987A). The Chandra X-ray data indicate non-radiative interaction of SN ejecta with a power-law density profile (rho \\propto r^{-n} with n ~ 7) with a pre-SN wind with a low mass loss rate of ~2 \\times 10^{-6} Msun/yr for a wind velocity of 10 km/sec, in close agreement with radio mass-loss rate estimates. The Chandra data show an unexpected, temporary rise in the 0.4--2.0 keV X-ray flux at ~100 days after explosion. SN ...
2001-01-01
Visualization by PIV of dynamic stall on a vertical axis wind turbine
Energy Technology Data Exchange (ETDEWEB)
The aerodynamic behavior of a vertical axis wind turbine (VAWT) is analyzed by means of 2D particle image velocimetry (PIV), focusing on the development of dynamic stall at different tip speed ratios. The VAWT has an unsteady aerodynamic behavior due to the variation with the azimuth angle {theta} of the blade's sections' angle of attack, perceived velocity and Reynolds number. The phenomenon of dynamic stall is then an inherent effect of the operation of a VAWT at low tip speed ratios, impacting both loads and power. The present work is driven by the need to understand this phenomenon, by visualizing and quantifying it, and to create a database for model validation. The experimental method uses PIV to visualize the development of the flow over the suction side of the airfoil for two different reference Reynolds numbers and three tip speed ratios in the operational regime of a small urban wind turbine. The field-of-view of the ...
2009-01-15
Vertical-axis wind turbine development in Canada
Energy Technology Data Exchange (ETDEWEB)
Recent Canadian progress in the development of the curved-blade Darrieus vertical-axis wind turbine (VAWT) is described. Cooperation between government, industry and power utilities in the conduct of field trials, over several years, has demonstrated improved performance and reliability of grid-coupled turbines of this type. The rated power of the VAWTs currently under test ranges from 30 kW, in a wind/diesel powerplant, to 230 kW, in an installation on an island in the Gulf of St. Lawrence. Progress has also been made in understanding the basic aerodynamic behavior of the VAWT and theoretical methods for performance and load prediction have correspondingly improved. A brief description is given of Project EOLE, a cooperative project between the federal government and the utility Hydro-Quebec to develop and test, during the next two to three years, a 4 MW VAWT prototype, which will be coupled to the power grid at a location on the south shore ...
1983-12-01
VAWT performance prediction - Description of a PC-based software
Energy Technology Data Exchange (ETDEWEB)
The Vertical Axis Wind Turbine (VAWT) offers a mechanically and structurally simple method of harnessing the energy of the wind. Fast and accurate predictions of the VAWT performance can be obtained using momentum models. Aerodynamic streamtube models are based on the conservation-of-momentum principle in a quasi-steady flow, by equating the forces of the rotor blades to the change in streamwise momentum through the turbine. An analytical model considering a multi-streamtube system divided into two parts has been developed to determine the aerodynamic blade loads and rotor performance of the Darrieus wind turbine (CARDAA computer code). This so-called double multiple-streamtube (DMS) model uses two constant interference factors in the induced velocities and accounts for vertical variations in the free stream velocity. It has been recently modified to produce an efficient software package appropriate for the needs of VAWT ...
1995-12-31
VAWT (Vertical-Axis Wind Turbine) stochastic loads produced by atmospheric turbulence
Blade fatigue life is an important element in determining the economic viability of the Vertical-Axis Wind Turbine (VAWT). A principal source of blade fatigue is thought to be the stochastic (i.e., random) aerodynamic loads created by atmospheric turbulence. This paper discusses the development of a model for the simulation of these stochastic loads, given the rotor geometry, operating conditions, and assumed turbulence properties. A Double-Multiple-Streamtube analysis is employed, which includes the effects of wind shear. Reynolds number variations, different airfoil sections and chord lengths along the blade span, and an empirical model for dynamic stall effects. Calculations are presented for the VAWT 34-m Test Bed currently being assembled at Bushland, Texas. Time histories of the loads, as well as their Fourier spectra, are presented and discussed. An unexpected finding is that the average output power is predicted to be more sensitive to ...
1987-01-01
Unification of Luminous Type 1 Quasars through CIV Emission
Using a sample of 30,000 quasars from SDSS-DR7, we explore the range of properties exhibited by high-ionization, broad emission lines, such as CIV 1549. Specifically we investigate the anti-correlation between L_UV and emission line EQW (the Baldwin Effect) and the "blueshifting" of high-ionization emission lines. The blueshift of the CIV emission line is nearly ubiquitous, with a mean shift of 810 km/s for radio-quiet (RQ) quasars and 360 km/s for radio-loud (RL) quasars, and the Baldwin Effect is present in both RQ and RL samples. Composite spectra are constructed as a function of CIV emission line properties in attempt to reveal empirical relationships between different line species and the SED. Within a two-component disk+wind model of the broad emission line region (BELR), where the wind filters the continuum seen by the disk component, we find that RL quasars are consistent with being dominated by the disk component, while BALQSOs are ...
2010-01-01
The vital importance of GIS : a workshop in project siting and development
Energy Technology Data Exchange (ETDEWEB)
Geographic information system (GIS) technology is now being used by wind energy developers who are required to consider and accommodate a wide variety of environmental and social considerations. This poster presentation discussed some of the new features available in current GIS technologies. High resolution imagery from satellites is being used to verify the accuracy of collected spatial data, as well as to investigate potential locations for meteorological towers, turbine sites, and roads. Slopes are easily calculated using GIS software tools, and digital elevation data can be used with high resolution aerial photography to determine routes for new roads and to establish available sites for crane pads. The GIS tools allow developers to consider protected ecological areas, wetlands and forests, and gives them the ability to better report project development considerations at public consultations. Wind resource grid outputs can also be ...
2010-07-01
The economic feasibility of producing hydrogen from sunlight and wind
International Nuclear Information System (INIS)
The feasibility of utilizing photoelectrochemical and electrolytical technologies to convert energy from the sun and wind into hydrogen was studied. In exploring opportunities to reduce the cost of hydrogen production through interaction with the electric utility grid, it was found that direct photoelectrochemical (PEC) conversion of sunlight has the economic potential to compete with direct photovoltaic/electrolysis, notwithstanding the significant stability and efficiency issues that are still awaiting solution. Interaction with the grid, while maximizing electrolizer use, makes a significant impact on the economics of producing hydrogen by photovoltaic/electrolysis, making wind-based systems also more economical. Electrolysis was found to be the optimal solution only with electricity from renewable sources or with less expensive non-peak electricity. On the other hand, the delivered cost of hydrogen was found to the lowest when electricity ...
1999-02-07
The NREL teetering hub rotor code: Final results and conclusions
Energy Technology Data Exchange (ETDEWEB)
Accurately predicting wind turbine blade loads and response is important for the proper design of wind turbines. The need to accurately predict both deterministic and stochastic blade loads is now widely recognized. Previous rotor code development and validation efforts at NREL have concentrated on prediction of deterministic and stochastic blade loads for rigid hub rotors. During the past year this effort was expanded for predicting blade and shaft loads for two-bladed teetering hub rotors. The NREL (formerly SERI) Teetering Rotor Analysis Program (STRAP), a derivative of the Force and Loads Analysis Program (FLAP), can include the effects of rotor undersling, delta-3 and the effects of a concentrated hub mass. The degrees of freedom include rotor teeter and symmetric and asymmetric rotor flap modes. A time-dependent, prescribed yaw motion can also be input to the code. Loads due to turbulent wind inputs are also ...
1991-12-01
We report on the spectral cross-calibration results of the Konus-Wind, the Suzaku/WAM, and the Swift/BAT instruments using simultaneously observed gamma-ray bursts (GRBs). This is the first attempt to use simultaneously observed GRBs as a spectral calibration source to understand systematic problems among the instruments. Based on these joint spectral fits, we find that 1) although a constant factor (a normalization factor) agrees within 20% among the instruments, the BAT constant factor shows a systematically smaller value by 10-20% compared to that of Konus-Wind, 2) there is a systematic trend that the low-energy photon index becomes steeper by 0.1-0.2 and Epeak becomes systematically higher by 10-20% when including the BAT data in the joint fits, and 3) the high-energy photon index agrees within 0.2 among the instruments. Our results show that cross-calibration based on joint spectral analysis is an important step to understanding the ...
2010-01-01
Seismic line across Wind River thrust fault, Wyoming
Energy Technology Data Exchange (ETDEWEB)
A seismic line was acquired by ARCO Exploration Company in 1977 in southern Freemont County and extends northeast from the deepest part of the Green River basin across the Wind River thrust onto crystalline basement rocks of the Wind River Mountains. A COCORP line across the area has been discussed previously, but the ARCO line shows more detailed information beneath the thrust. The seismic line is significant because it shows a strong reflection at the base of the Precambrian granite, which overlies a sedimentary rocks of the northern Green River basin. It also illustrates an apparent anticline beneath the thrust fault which is the result of lateral velocity variation caused by a shallow wedge of low-velocity Miocene sediments superimposed on a velocity pull-up related to the high-velocity Precambrian granite. The effects of the velocity variations can be analyzed by ray tracing and by studying the near offset and far offset stacks of the ...
1985-05-01
Energy Technology Data Exchange (ETDEWEB)
The Green River Basin is a northwest-southeast elongate structural feature located in southwestern Wyoming. Bounded by three basement uplifts, this complex mountain front basin possesses tremendous gas reserves. Production has been limited to a few structures, such as the Pinedale Anticline, because of the great depth of the basin. The Pinedale Anticline is an elongate structure that parallels the front of the Wind River Thrust. Earlier research has suggested that the anticline is not related to basement, but rather is associated with a foreland detachment structure. A new, high-resolution aeromagnetic survey has been modelled in detail and the results indicate that the Pinedale Anticline may actually be a basement related structure. Profile modelling normal to the anticline from the LaBarge Platform to the Wind River Mountains suggests that not only is Pinedale Field situated on a possible basement structure, but also that additional, ...
1996-06-01
New perspectives on renewable energy systems based on hydrogen
International Nuclear Information System (INIS)
Current hydrocarbon-based energy systems, current energy consumption and the push towards the utilization of renewable energy sources, fuelled by global warming and the need to reduce atmospheric pollution are discussed. The consequences of climatic change and the obligation of Annex B countries to reduce their greenhouse gas emissions in terms of the Kyoto Protocols are reviewed. The role that renewable energy sources such as hydrogen, solar and wind energy could play in avoiding the most catastrophic consequences of rapidly growing energy consumption and atmospheric pollution in the face of diminishing conventional fossil fuel resources are examined. The focus is on hydrogen energy as a means of storing and transporting primary energy. Some favorable characteristics of hydrogen is its abundance, the fact that it can be produced utilizing renewable or non-renewable sources, and the further fact that its combustion produces three times more energy per unit of mass ...
1999-09-27
National Uranium Resource Evaluation: Lander Quadrangle, Wyoming
Energy Technology Data Exchange (ETDEWEB)
The Lander Quadrangle, Wyoming, was evaluated to a depth of 1500 m to identify environments and delineate areas that exhibit characteristics favorable for the the occurrence of uranium deposits. The evaluation used criteria established for the National Uranium Resources Evaluation program. The methods of surface investigations included evaluation of aerial radiometric and hydrogeochemical stream-sediment reconnaissance data, verification of some reported uranium occurrences, and general field geology with rock, water, and sediment sampling. The subsurface evaluation was accomplished through the use of 230 various oil-well logs. The results of this investigation identified three environments favorable for sandstone uranium deposits in Eocene fluvial sediments. These environments are within the Battle Spring and upper Fort Union Formations of the northern Great Divide Basin and within the Wind River and the Wagon Bed Formations of the southwest ...
1982-07-01
National Uranium Resource Evaluation: Lander Quadrangle, Wyoming
International Nuclear Information System (INIS)
The Lander Quadrangle, Wyoming, was evaluated to a depth of 1500 m to identify environments and delineate areas that exhibit characteristics favorable for the the occurrence of uranium deposits. The evaluation used criteria established for the National Uranium Resources Evaluation program. The methods of surface investigations included evaluation of aerial radiometric and hydrogeochemical stream-sediment reconnaissance data, verification of some reported uranium occurrences, and general field geology with rock, water, and sediment sampling. The subsurface evaluation was accomplished through the use of 230 various oil-well logs. The results of this investigation identified three environments favorable for sandstone uranium deposits in Eocene fluvial sediments. These environments are within the Battle Spring and upper Fort Union Formations of the northern Great Divide Basin and within the Wind River and the Wagon Bed Formations of the southwest ...
1982-01-01
Modelling of unsteady flows on wind turbines
Environmental Research Database
ObjectivesTo obtain a benchmarked unsteady aerodynamic code for the S809 aerofoil; including Dynamic Stall. ~%~~%~The code will be that of Leishman & Beddoes suitably configured for the aerofoil's use on wind tubines. ~%~~%~To involve the international community during the assessment phase after benchmarking.~%~~%~To compare the data collected with that from the NWTC experiment.~%~~%~To improve the predictive capability of extant horizontal axis wind turbine performance codes. ~%~~%~To be compliant with b [continued...]DescriptionIn December 2000 the National Renewable Energy Laboratory (USA) held an international seminar to consider the predictive capabilities of w ind-turbine codes using their recently measured data. This highlighted the need for a detailed consideration of the codes sub-system with proper benc hmarking (became part of an ...
2007-01-30
Full scale testing of wind turbine blade to failure - flapwise loading
Energy Technology Data Exchange (ETDEWEB)
A 25m wind turbine blade was tested to failure when subjected to a flapwise load. With the test setup, it was possible to test the blade to failure at three diffe-rent locations. The objective of these tests is to learn about how a wind turbine blade fails when exposed to a large flapwise load and how failures propagate. The report shows also results from ultra sonic scan of the surface of the blade and it is seen to be very useful for the detection of defects, especially in the layer between the skin laminate and the load carrying main spar. Acoustic emission was successfully used as sensor for the detection of damages in the blade during the test. The report contains measurements of the total deflection of the blade, the local deflection of the skin and the load carrying main spar and also measurement of strain all as a function of the applied load and up to failure of the blade. The 'post mortem' analysis and description of ...
2004-06-01
Edge filter and fringe imaging for laser Doppler wind speed measurement
Optical measurement of the Doppler shift of laser backscatter, using a near-IR, visible, or ultraviolet laser, is potentially more robust and field reliable than coherent, heterodyne measurement with an IR laser. The direct measurement of the displacement of Fabry-Perot interference fringes is possible, but entails expensive, technically challenging, imaging detectors. The 'edge technique' permits Doppler shift measurements with relatively simple detectors and detector electronics, and has been implemented with Fabry-Perot etalons and with atomic line filters. Simple analytical models of the fringe imaging and edge detection techniques are presented, permitting ready calculation of the potential performance of either, for various atmospheric conditions and for various lidar hardware configurations. The predictions of the analytical models are confirmed by computer models, which in turn allow more detailed considerations of complicating factors such as solar backgrounds and the Rayleigh ...
1997-08-01
EVOLUTION OF MASSIVE STARS WITH PULSATION-DRIVEN SUPERWINDS DURING THE RED SUPERGIANT PHASE
International Nuclear Information System (INIS)
Pulsations driven by partial ionization of hydrogen in the envelope are often considered important for driving winds from red supergiants (RSGs). In particular, it has been suggested by some authors that the pulsation growth rate in an RSG can be high enough to trigger an unusually strong wind (or a superwind), when the luminosity-to-mass ratio becomes sufficiently large. Using both hydrostatic and hydrodynamic stellar evolution models with initial masses ranging from 15 to 40 M_s_u_n, we investigate (1) how the pulsation growth rate depends on the global parameters of supergiant stars and (2) what would be the consequences of a pulsation-driven superwind, if it occurred, for the late stages of massive star evolution. We suggest that such a superwind history would be marked by a runaway increase, followed by a sudden decrease, of the wind's mass-loss rate. The impact on the late evolution of massive stars would be ...
2010-07-01
Energy Technology Data Exchange (ETDEWEB)
Architecture of hydrocarbon-bearing sandstone reservoirs of the Paleocene Fort Union Formation in the Wind River basin, Wyoming, was studied using lithofacies, grain size, bounding surfaces, sedimentary structures, internal organization, and geometry. Two principal groups of reservoirs, both erosionally based and fining upward, consist of either conglomeratic sandstone or sandstone lithofacies. Two types of architecture were recognized in conglomeratic sandstone reservoirs: (1) heterogeneous, multistacked, lenticular and (2) homogeneous, multiscoured, wedge-sheet bodies. Three types of architecture were recognized in sandstone reservoirs: (3) heterogeneous, multistacked, elongate; (4) homogeneous, multilateral, lenticular; and (5) homogeneous, ribbon-lensoid bodies. Conglomeratic sandstone reservoirs in the southern and southwestern parts of the basin suggest deposition in gravel-bedload fluvial systems influenced by provenance uplift of the Granite and southern ...
1991-06-01
A simple model for the short-time evolution of near-surface current and temperature profiles
A simple analytical/numerical model has been developed for computing the evolution, over periods of up to a few hours, of the current and temperature profile in the upper layer of the ocean. The model is based upon conservation laws for heat and momentum, and employs an eddy diffusion parameterisation which is dependent on both the wind speed and the wind stress applied at the sea surface. Other parameters such as the bulk-skin surface temperature difference and CO$_2$ flux are determined by application of the Molecular Oceanic Boundary Layer Model (MOBLAM) of Schluessel and Soloviev. A similar model, for the current profile only, predicts a temporary increase in wave breaking intensity and decrease in wave height under conditions where the wind speed increases suddenly, such as, for example, during gusts and squalls. The model results are compared with measurements from the lagrangian Skin Depth Experimental Profiler ...
2005-01-01
$\\gamma$-ray bursts from internal shocks in a relativistic wind temporal and spectral properties
We construct models for gamma-ray bursts where the emission comes from internal shocks in a relativistic wind with a highly non uniform distribution of the Lorentz factor. We follow the evolution of the wind using a very simplified approach where a large number of layers interact by direct collisions but where all pressure waves have been suppressed. We suppose that the magnetic field and the electron Lorentz factor reach large equipartition values in the shocks. Synchrotron photons emitted by the relativistic electrons have a typical energy in the gamma-ray range in the observer frame. Synthetic bursts are constructed as the sum of the contributions from all the internal elementary shocks and their temporal and spectral properties are compared to the observations. We reproduce the diversity of burst profiles, the ``FRED'' shape of individual pulses and the short time scale variability. Synthetic bursts also satisfy the duration-hardness ...
1998-01-01
British Library Electronic Table of Contents (United Kingdom)
Malformations in farmed fish are a prime research topic as it has a major impact on fish welfare and on the economical value of the product. In this study, the genetic component of spine deformities was estimated in European sea bass, a major species of Mediterranean aquaculture, with the use of a posteriori reconstruction of pedigree with microsatellites. Our population exhibited a very high malformation rate (81%), probably due to intense swimming of fish during pre-growing. The heritability of global spine deformities was evaluated to be 0.21?0.04 on the underlying scale (0.33?0.06 for lordosis, 0.13?0.04 for scoliosis). Deformities scored by an internal or external examination turned out to be genetically the same trait (genetic correlations>0.9), although phenotypic correlations were ...
2009-01-01
Using "EC-Assess" to Assess a Small Biofuels Project in Honduras
Biofuels may contribute to both rural economic development and climate change mitigation and adaptation. The Gota Verde Project in Yoro, Honduras, attempts to demonstrate the technical and economic feasibility of small-scale biofuel production for local use by implementing a distinctive approach to feedstock production that encourages small farm sizes, mixed cropping of biofuel feedstock from Jatropha and food crops, particularly corn and beans, grown side by side on the same farmland and the total involvement of small rural farmers. But is the project sustainable? Using EC-Assess, the Earth Charter ethics-based assessment tool, to assess the sustainability of this project, the author found that in some assessment categories the actions surpassed the intended objectives, showing that the project was achieving certain Earth Charter goals without specifically stating its intention to address them. (Contains 3 images, 3 figures and 2 notes.)
2010-09-01
Energy Technology Data Exchange (ETDEWEB)
Two days of hearings on Titles V and X of the Water Resources Development Act of 1983 brought comments from representatives of several states, farm and transport industries, environmental groups, and concerned taxpayers. Title V requires the collection of new funds from users beyond a ceiling set for annual spending on water projects, while Title X proposes a cost-sharing partnership for certain navigation projects. Witnesses were requested to confine their comments to constructive alternatives to the proposed legislation. Additional material on the deep river study and statements submitted for the record follow the testimony of 28 witnesses.
1984-01-01
State of the art report on bituminized waste forms of radioactive wastes
International Nuclear Information System (INIS)
In this report, research and development results on the bituminization of radioactive wastes are closely reviewed, especially those regarding waste treatment technologies, waste solidifying procedures and the characteristics of asphalt and solidified forms. A new concept of the bituminization method is suggested in this report which can improve the characteristics of solidified forms. Stable solid forms with high leach resistance, high thermal resistance and good compression strength were produced by the suggested bituminization method, in which spent polyethylene from agricultural farms was added. This report can help further research and development of improved bituminized forms of radioactive wastes that will maintain long term stabilities in disposal sites. (author). 59 refs., 19 tabs., 18 figs
1997-06-08
Simulation and design of membrane plants with AspenPlus
Energy Technology Data Exchange (ETDEWEB)
In this paper the simulation of hybrid processes containing membrane units will be discussed. For this purpose a user-defined module for simulation and design of membrane processes was implemented into the simulation program AspenPlus. The advantages can be summarized as follows: - any combination of membrane processes with all other units already implemented in AspenPlus is possible, including internal recycle streams, - utilization of the physical property models and data bases of AspenPlus is possible, - cost and sensitivity analysis can be performed. These benefits are demonstrated in detail for a membrane vapor recovery unit for the treatment of tank farm off-gas, for a two-stage reverse osmosis plant for organic/-organic separations and for a combination of distillation and pervaporation for the separation of a dimethylcarbonate/methanol mixture. (orig.)
1996-10-01
Persistent halogenated compounds in two typical marine aquaculture zones of South China
British Library Electronic Table of Contents (United Kingdom)
Samples of two seawater farmed fish (crimson snapper (Lutjanus erythopterus) and snubnose pompano (Trachinotus blochii)), water, air, sediment, fish feed, macroalgae and phytoplankton were collected from two estuarine bays (Daya Bay and Hailing Bay) in South China. The concentrations of persistent halogenated compounds (PHCs) including polybrominated diphenyl ethers (PBDEs), organochlorine pesticides and polychlorinated biphenyls (PCBs) varied widely with the different sample matrices under investigation. The compositional patterns in fish, fish feed, macroalgae and phytoplankton, as well as the good correlations between the abundances of p,pprime-DDT and BDE-209 and their metabolites (i.e., p,pprime-DDD and p,pprime-DDE for p,pprime-DDT and BDE-47 for BDE-209) in fish indicated the occurr...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
The study investigates the possibility of enhancing crop water productivity in the parts of Northwest India where groundwater quality is marginal and canal water supply is severely scarce. Soil, Water, Atmosphere and Plant (SWAP) model was calibrated and validated in three farmers' fields with varying canal water availability and groundwater quality in the Kaithal Irrigation Circle of the Bhakra Canal system, Haryana. On the basis of predicted and observed soil water content, pressure heads, salt concentration at 2 week intervals and crop yields, the model was found suitable for use in the region. A few nomographs were prepared to provide a graphical method to predict the effect of different combinations of water quality and depth of water application on crop yield and soil salinity and to...
2008-01-01
Liquid radioactive waste discharges from B plant to cribs
Energy Technology Data Exchange (ETDEWEB)
This engineering report compiles information on types and quantities of liquid waste discharged from B-Plant directly to cribs, ditches, reverse wells, etc., that are associated with B-Plant. Waste discharges to these cribs via overflow form 241-B, 241-BX, and 241-BY tank farms, and waste discharged to these cribs from sources other than B-Plant are discussed.Discharges from B-Plant to other cribs, unplanned releases, or waste remaining in tanks are not included in the report. Waste stream composition information is used to predict quantities of individual chemicals sent to cribs. This provides an accurate mass balance of waste streams from B-Plant to these cribs. These predictions are compared with known crib inventories as a verification of the process.
1996-05-29
Isolation and molecular identification of small ruminant mycoplasmas in Jordan
British Library Electronic Table of Contents (United Kingdom)
Mycoplasma infections of small ruminants are known to exist in the Mediterranean region, Asia, Africa and cause significant economic impacts but little is known of the Mycoplasma spp. in sheep and goats in the Middle East. During the period of 2002-2003, 104 flocks of local sheep and goats (17 sheep, 27 goat and 60 mixed flocks) were surveyed for the occurrence of mycoplasma infections in Northern Jordan. The clinical signs seen in the studied flocks were, to varying degrees, mastitis in sheep and goats, arthritis, mainly in kids, and pneumonia in both sheep and goats of most age groups. Small ruminant farms were sampled and pooled milk samples and nasal swabs were collected for culture and isolation of mycoplasma. Mycoplasmas were isolated from 17 (26%) of the 62 milk samples and 12 (3.9%...
2006-01-01
Energy Technology Data Exchange (ETDEWEB)
An investigation of current dual-fuel natural gas/diesel engine design, performance, and emissions was conducted. The most pressing technological problems associated with dual-fuel engine use were identified along with potential solutions. It was concluded that dual-fuel engines can achieve low NOx and particulate emissions while retaining fuel-efficiency and BMEP levels comparable to those of diesel engines. The investigation also examined the potential economic impact of dual-fuel engines in diesel-electric locomotives, marine vessels, farm equipment, construction, mining, and industrial equipment, and stand-alone electricity generation systems. Recommendations for further additional funding to support research, development, and demonstration in these applications were then presented.
1994-11-01
Development of a solar thermal storage system suitable for the farmhouse heating in northeast China
Energy Technology Data Exchange (ETDEWEB)
This study reported on the performance of a passive solar radiant floor heating system designed for standard energy-saving farmhouses in northeast China. Weather data in the region was analyzed in terms of solar radiation, temperature, humidity and light levels. The heating characteristics of the building materials such as windows, doors, walls and roofs were also analyzed along with the indoor thermal environment of the farmhouse. The heating load was then calculated along with the size of the thermal storage element and the area of the collector element. The passive solar radiant floor heating system was designed for heating during the winter and cooling in summer. According to the results, the heating characteristics of the system have the potential to improve farming villages environment and the use of renewable energy.
2010-07-01
British Library Electronic Table of Contents (United Kingdom)
Phreatic groundwater pumping is affecting water availability for crops in areas with a shallow water table. This can reduce crop growth and so affect farm income. There is a need for a generic and transparent method to assess the agricultural damage caused by water table drawdown. This paper proposes such a method that consists of 'damage tables' relating agricultural production losses to the groundwater regime for different soil/crop combinations found in Northern Belgium. The damage tables are constructed based on numerous simulations with the agrohydrological model SWAP, in which the bottom boundary conditions are gradually changed to reflect different groundwater regimes. The credibility of the resulting metamodel is assessed in three ways: using (1) field data, (2) an existing local e...
2010-01-01
Environmental Research Database
ObjectivesThe vision The Centre's vision is a rural transformation in the developing world where smallholder households massively increase their use of trees in agricultural landscapes to improve their food security, nutrition, income, health, shelter, energy resources and environmental sustainability. This vision is founded upon three basic tenets: 1. The growing importance of trees and treebased systems in sustaining livelihoods and agroecosystems; 2. The Centre's experience and comparative adv [continued...]DescriptionBackground: The International Council for Research in Agroforestry (ICRAF) was created in response to a visionary study in the mid-1970s led by forester John Bene of Canada's International Development Research Centre (IDRC). The study coined the term 'agroforestry' and called for global recognition of the key role trees play on farms. This led to the establishment of ICRAF in 1978 to promote agroforestry research in developing countries. Intended ...
2016-01-31
Computing in high energy physics
Energy Technology Data Exchange (ETDEWEB)
This book deals with advanced computing applications in physics, and in particular in high energy physics environments. The main subjects covered are networking; vector and parallel processing; and embedded systems. Also examined are topics such as operating systems, future computer architectures and commercial computer products. The book presents solutions that are foreseen as coping, in the future, with computing problems in experimental and theoretical High Energy Physics. In the experimental environment the large amounts of data to be processed offer special problems on-line as well as off-line. For on-line data reduction, embedded special purpose computers, which are often used for trigger applications are applied. For off-line processing, parallel computers such as emulator farms and the cosmic cube may be employed. The analysis of these topics is therefore a main feature of this volume.
1986-01-01
Changes in Soil Properties and Vegetable Growth in Preparation for Organic Farming in Hawaii
British Library Electronic Table of Contents (United Kingdom)
Changes in soil properties and vegetable growth were quantified on a low-fertility tropical soil. Four treatments (two composts, urea, and control) were applied to an Oxisol (Rhodic Haplustox, Wahiawa series) in a field on Oahu, Hawaii. Chinese cabbage (Brassica rapa, Chinensis group) and eggplant (Solanum melongena) were grown sequentially as test crops. Soil quality as measured by hot-water-soluble carbon, dehydrogenase activity, and cation exchange capacity (CEC) increased by compost amendments. Total organic carbon or carbon dioxide (CO2) respiration rate did not correlate with the soil amendments. Nitrogen (N) nutrition was the main factor that improved growth and carotenoid content in cabbage. The urea treatment promoted better growth in cabbage, whereas good-quality compost, made of...
2011-01-01
British Library Electronic Table of Contents (United Kingdom)
Climate change is one of the main global issues of modern time. Ever increasing demand for food/feed and the need for higher environmental standards require shaping of the agricultural activities toward ecological and more sustainable efficient systems. One of the principal ways of attaining higher productivity and environmental standards is identification and adoption of beneficial management practices (BMP) by reviewing the conventional agricultural activities. The BMP are agricultural practices that promote sustainable land stewardship and maintain/increase profitability of farms. The BMP are from both crop and animal production systems and tradeoffs between the two systems could provide several opportunities in reducing, removing and/or avoiding of greenhouse gases (GHG) emissions. Des...
2011-01-01
Balancing Energy, Food, Natural Resources and Environment in Nepal
Energy Technology Data Exchange (ETDEWEB)
Nepal could harness less than 1% of its 83000 MW hydropower potential. Pancheshwar Multipurpose Project (6720 MW) is a bi-national project on Mahakali River bordering between Nepal and India. The earnings from: electricity (NRs. 34.55 billion/year); irrigation (NRs. 5.55 billion/year), fish farming (NRs. 8.65 billion/year), carbon trading (NRs. 4.42 billion/year) and many billions from other sources e.g. eco-tourism, industry, horticulture, herbiculture, floriculture, sericulture, rafting and water sports, educational and vocational training and other industrial/commercial activities can catapult the socioeconomic horizon of Nepal. Hence, PMP should be jointly developed in the earliest and build confidence for the further hydropower development.
2010-09-15
Absorption of carbon dioxide in waste tanks
International Nuclear Information System (INIS)
Air flow rates and carbon dioxide concentrations of air entering and exiting eight H-Area waste tanks were monitored for a period of one year. The average instanteous concentration of carbon dioxide in air is within the range reported offsite, and therefore is not affect by operation of the coal-fired power plant adjacent to the tank farm. Waste solutions in each of the tanks were observed to be continuously absorbing carbon dioxide. The rate of absorption of carbon dioxide decreased linearly with the pH of the solution. Personnel exposure associated with the routine sampling and analysis of radioactive wastes stored at SRP to determine the levels of corrosion inhibitors in solution could be reduced by monitoring the absorption of carbon dioxide and using the relationship between pH and carbon dioxide absorption to determine the free hydroxide concentration in solution.
1987-09-01
The interaction of accretion disks with the magnetospheres of young stars can produce X-winds and funnel flows. With the assumption of axial symmetry and steady state flow, the problem can be formulated in terms of quantities that are conserved along streamlines, such as the Bernoulli integral (BI), plus a partial differential equation (PDE), called the Grad-Shafranov equation (GSE), that governs the distribution of streamlines in the meridional plane. The GSE plus BI yields a PDE of mixed type, elliptic before critical surfaces where the flow speed equals certain characteristic wave speeds are crossed and hyperbolic afterward. The computational difficulties are exacerbated by the locations of the critical surfaces not being known in advance. To overcome these obstacles, we consider a variational principle by which the GSE can be attacked by extremizing an action integral, with all other conserved quantities of the problem explicitly included as part of the overall ...
2007-01-01
Wolf-Rayet stars as gamma-ray burst progenitors
British Library Electronic Table of Contents (United Kingdom)
The collapsar scenario for long gamma-ray bursts requires rapidly rotating Wolf-Rayet stars as progenitor stars. We highlight two possible ways out of the dilemma that the strong winds of Wolf-Rayet lead to a fast spin-down. One way is to restrict the duration of the Wolf-Rayet phase to a short time span at the end of the star's evolution. We show that this appears to apply to GRB 021004. The other way is to choose a sub-solar metallicity, thus limiting the Wolf-Rayet wind efficiency. We discuss corresponding stellar evolution models and show that a metallicity limit of about 1/10th solar, as it is required by the models, may be consistent with the empirical gamma-ray burst rate.
2010-01-01
Understanding renewable energy systems
Energy Technology Data Exchange (ETDEWEB)
Beginning with an overview of renewable energy sources including biomass, hydroelectricity, geothermal, tidal, wind and solar power, this book explores the fundamentals of different renewable energy systems. The main focus is on technologies with high development potential such as solar thermal systems, photovoltaics and wind power. This text not only describes technological aspects, but also deals consciously with problems of the energy industry. In this way, the topics are treated in a holistic manner, bringing together maths, engineering, climate studies and economics, and enabling readers to gain a broad understanding of renewable energy technologies and their potential. The book also contains a free CD-ROM resource, which includes a variety of specialist simulation software and detailed figures from the book. (Author)
2005-01-15
The Darrieus-type Vertical Axis Wind Turbine (VAWT) presents a variety of unusual structural problems to designers. The level of understanding of these structural problems governs, to a large degree, the success or failure of today's rotor designs. A survey is presented of the technology available for rotor structural design with emphasis on the DOE research program now underway. Itemizations are included of the major structural issues unique to the VAWT along with discussion of available analysis techniques for each problem area. It is concluded that tools are available to at least approximately address the most important problems. However, experimental data for confirmation is rather limited in terms of volume and the range of rotor configurations tested.
1982-01-01
Sandia National Laboratories has erected a research oriented, 34- meter diameter, Darrieus vertical axis wind turbine near Bushland, Texas. This machine, designated the Sandia 34-m VAWT Test Bed, is equipped with a large array of strain gauges that have been placed at critical positions about the blades. This manuscript details a series of four-point bend experiments that were conducted to validate the output of the blade strain gauge circuits. The output of a particular gauge circuit is validated by comparing its output to equivalent gauge circuits (in this stress state) and to theoretical predictions. With only a few exceptions, the difference between measured and predicted strain values for a gauge circuit was found to be of the order of the estimated repeatability for the measurement system.
1988-08-01
International Nuclear Information System (INIS)
Presented here is the calculation results of tidal field of Daya Bay by using pseudospectral method. According to the calculation results about the tidal field and measured value of wind in Daya Bay area, the diffusion of radionuclide from Daya Bay Nuclear Power Plant is simulated by using particle random walk model. The simulation results about the relative concentration distribution of the radionuclides and the trajectory of the distribution centrode are obtained, taking account of tidal current, wind and turbulent current. These results can provide information not only for the reasonable discharge of the radionuclides from Daya Bay Nuclear Power Plant, but also for understanding the potential effect on environment due to the normal operation of Daya Bay Nuclear Power Plant. (authors)
2009-11-01
On the role of the Jeffreys'sheltering mechanism in the sustain of extreme water waves
The effect of the wind on the sustain of extreme water waves is investigated experimentally and numerically. A series of experiments conducted in the Large Air-Sea Interactions Facility (LASIF) showed that a wind blowing over a strongly nonlinear short wave group due to the linear focusing of a modulated wave train may increase the life time of the extreme wave event. The expriments suggested that the air flow separation that occurs on the leeward side of the steep crests may sustain longer the maximum of modulation of the focusing-defocusing cycle. Based on a Boundary-Integral Equation Method and a pressure distribution over the steep crests given by the Jeffreys'sheltering theory, similar numerical simulations have confirmed the experimental results
2006-01-01
Modeling of power-system dynamics in the medium-time scale
Energy Technology Data Exchange (ETDEWEB)
This thesis deals with the reduced-order modeling of electrical machines and interconnected power systems in the medium time scale using integral manifold techniques. First, an improved model for power system stabilizer design that captures the damping due to the amortisseur windings while retaining the simplicity of the DeMello-Concordia model is presented. Second, time scales of the regulated synchronous machine are analyzed using the linearized models, and the well-known effects of the high-gain regulator on the system are explained. A reduced-order model that captures the damping due to the power-system stabilizer is presented. Third, speed-damping terms are obtained in the swing equation in a multimachine environment by approximating the integral manifold associated with fast damper windings. This provides a theoretical basis for the practice of adding cross-damping terms to the swing equation to account for damping present in the system. ...
1991-01-01
British Library Electronic Table of Contents (United Kingdom)
Turbulent shear flows on shallow continental shelves (here shallow means that the interaction with the solid, no-slip bottom is important) are of great importance because tide- and wind-driven flows on the shelf are drivers of the transfer of momentum, heat, and mass (gas) across the air?sea interface. These turbulent flows play an important role because vertical mixing and current are vectors for the transport of sediment and bioactive material on continental shelves. Understanding the dynamics of this class of flows presents complications because of the presence of a free surface and also because the flow can be driven by a pressure gradient (a tidal current), a stress at the free surface (a wind-driven current), or a combination of both. In addition, the flow can be modified by the pres...
2011-01-01
Investigation of the steady state and transient operating behaviour of a 20 kW pressure electrolyser
Energy Technology Data Exchange (ETDEWEB)
The present paper describes the investigation of the static and dynamic behaviour of an 20 kW pressure electrolyser. The suitability for a coupled operating regime with a wind power plant has been investigated. At first the static behaviour has been analysed. The share of oxygen in hydrogen gas is lower than 0.5 Vol%. But reaching the temperature limit of 80 deg C leads to a switch off of the electrolyser, accompanied by an increase of the oxygen share in hydrogen gas up to 1.3 Vol%. Therefore, an improvement of the cooling system is necessary. Secondly, the electrolyser was excited by different step signals for load changing and finally, the electrolyser has been controlled by the power output signal of the windmill. The investigation shows that the development of a direct coupled wind-hydrogen system will be only a small step. 3 refs.
1998-07-01
Influence of weather on the behaviour of outdoor-wintered beef cattle in Scandinavia
British Library Electronic Table of Contents (United Kingdom)
The aim of the present investigation was to study the effect of weather and available protection on the behaviour of outdoor-wintered beef cattle (Bos taurus). A herd of 78-85 cattle head was studied during four winter months in the Southwest of Sweden. Protection was offered by coniferous forest situated on and around the 12ha pasture, which we divided into protection categories. During 240h we observed 10 cows and 10 heifers as focal animals (each 3h/month) during day time and adjusted observation times to the altitude of the sun. Close to the animals and at an unprotected spot of the pasture we measured temperature, wind speed and solar radiation and combined these variables to a single measure called Wind Chill Temperature (WCT). During observations the animals were in the forest in 12...
2011-01-01
Gamma-rays and neutrinos from the pulsar wind nebulae
Energy Technology Data Exchange (ETDEWEB)
We construct the time-dependent radiation model for the pulsar wind nebulae (PWNe), assuming that leptons are accelerated in resonant scattering with heavy nuclei, which are injected into the nebula by the pulsar. The equilibrium spectra of these particles inside the nebula are calculated taking into account their radiation and adiabatic energy losses. The spectra of {gamma}-rays produced by these particles are compared with the observations of the PWNe emitting TeV {gamma}-rays and predictions are made for the expected {gamma}-ray fluxes from other PWNe. Expected neutrino fluxes and neutrino event rates in a 1 km{sup 2} neutrino detector from these nebulae are also calculated. It is concluded that only the Crab Nebula can produce a detectable neutrino event rate in the 1 km{sup 2} neutrino detector. Other PWNe can emit TeV {gamma}-rays on the level of a few percent of that observed from the Crab Nebula.
2005-08-01
GPM on The High Capapcity Centrifuge
National Aeronautics and Space Administration (NASA)
GPM moves from the clean room to the test chamber on a dolly without wheels. Compressed air is pumped out under airpads that float the Spacecraft on a bed of air. nThe wind generated when the centrifuge moves at its maximum speed are more than 200 mph - that's tornado speed. But since they move with the centrifuge the satellites tested only feel 20 mph winds. nLeaning outward at 45 degrees for one test orientation, GPM comes within 28 inches of the wall. When lifted onto the platform it cleared the ceiling by only five inches. nNatural audio only. nVideo Credit: Brooke Harris n
2011-10-19
Effects of linear, ambient wind shear on simulated mammatus-like clouds
British Library Electronic Table of Contents (United Kingdom)
A suite of numerical experiments is conducted to extend our previous studies to explore the effects of linear, ambient wind shear on simulated mammatus-like clouds. Increasing values of unidirectional shear result in banded cloud bases, and for the strongest shears roll-type quasi-two-dimensional convection results rather than three-dimensional lobe morphology. Two observed soundings were used, and the sounding with a drier, shallower sub-cloud layer appeared to be most strongly affected by the presence of the ambient shear. The drier sounding also had less snow in the mammatus lobes owing to sublimation. Copyright Copyright 2009 Royal Meteorological Society
2009-01-01
Economic overview of vertical axis wind turbines
Sandia Laboratories, as part of its investigation of the Darrieus Vertical Axis Wind Turbine (VAWT), has been involved recently in an economic assessment of the concept. The class of VAWT's investigated use curved, fixed-pitch blades of constant section rigidly attached to a vertical rotating tower. Qualitatively, the main advantages of the VAWT over more conventional, propeller-type machines are the elimination of yaw controls, the placement of mechanical equipment at ground level, its amenability to simple, low-cost blade fabrication techniques, and aerodynamic stall characteristics which eliminate the need for active pitch control devices. The main disadvantages relative to modern propeller machines are a somewhat lower aerodynamic efficiency (about 10% lower), the limited ability of the rotor to self-start, and generally lower rotor operating RPM's, which leads to higher torque capacity requirements for the drive train.
1979-01-01
Economic overview of vertical axis wind turbines
The class of vertical axis wind turbines (VAWT) investigated use curved, fixed-pitch blades of constant section rigidly attached to a vertical rotating tower. Qualitatively, the main advantages of the VAWT over more conventional, propeller-type machines are the elimination of yaw controls, the placement of mechanical equipment at ground level, its amenability to simple, low-cost blade fabrication techniques, and aerodynamic stall characteristics which eliminate the need for active pitch control devices. The main disadvantages relative to modern propeller machines are a somewhat lower aerodynamic efficiency (about 10 percent lower), the limited ability of the rotor to self-start, and generally lower rotor operating RPM's, which leads to higher torque capacity requirements for the drive train.
1979-01-01
This report is part of a four-volume study of Darrieus vertical axis wind turbine (VAWT) economics. This volume describes a computer model of VAWT cost and performance factors useful for system design and optimization. The content and limitations of the model are outlined. Output data are presented to demonstrate selection of optima and to indicate sensitivity of energy cost to design parameter variations. Optimized specifications generated by this model for six point designs are summarized. These designs subsequently receive a detailed economic analysis discussed in Volume IV. An appendix is included with a FORTRAN IV listing of the model and a description of the input/output characteristics.
1979-08-01
Development towards optimization of emergency countermeasures
International Nuclear Information System (INIS)
We report on severe accident scenarios consequences evaluation in connection to the applied emergency countermeasures and use of the PC COSYMA code. We present some of the results for the reactor core melt accident assumed to happen at the 632 MWE PWR Krsko Nuclear Power Plant in Slovenia. The efficiency of several potential countermeasures in limiting the late health effects was studied. Regarding the source term, the majority of release parameters are as specified for category 2 in the German Risk Study. Site specific data were used. As the outside (meteorologic) conditions during the potential accident onset can be very different, the study limited to the deterministic runs, assuming the wind direction upstream the Sava river into the WNW direction, wind speed of 5 ms -1 and the C Pasquill stability category. The population distribution file was formed from the NEK-FSAR data for the 1991. (author)
1995-09-11
Customized airfoils and their impact on VAWT (Vertical-Axis Wind Turbine) cost of energy
Sandia National Laboratories has developed a family of airfoils specifically designed for use in the equatorial portion of a Vertical-Axis Wind Turbine (VAWT) blade. An airfoil of that family has been incorporated into the rotor blades of the DOE/Sandia 34-m diameter VAWT Test Bed. The airfoil and rotor design process is reviewed. Comparisons with data recently acquired from flow visualization tests and from the DOE/Sandia 34-m diameter VAWT Test Bed illustrate the success that was achieved in the design. The economic optimization model used in the design is described and used to evaluate the effect of modifications to the current Test Bed blade. 1 tab., 11 figs., 13 refs.
1990-01-01
This report is a compilation of the Chalk Point surface weather and ambient atmospheric profile data for the second intensive test period, June 14-24, 1976. The atmospheric profiles were made using rawinsonde instrumentation. The compilation includes the 0700 EST daily weather chart, hourly surface observations from Chalk Point, Patuxent River Naval Test Center, MD and Andrews Air Force Base, MD. Temperature, relative humidity, dew point, wind speed and wind direction are presented in graphical profiles. All other data are presented in tabular form.
1977-01-01
Energy Technology Data Exchange (ETDEWEB)
Papers are presented on the modeling, dispersion, formation, transformation, monitoring and biological effects of atmospheric pollution. Specific topics include a prognostic mesoscale model for pollutant transport and diffusion, commuter exposure modeling, a Gaussian plume model for an urban area, carbon monoxide dispersion in an urbanized area, wind-tunnel modeling of flue gas dispersion, the regional-scale transport of fine aerosol components in eastern North America, and a Markov process for the generation of hourly average wind vectors. Attention is also given to photochemical aerosol formation in multicomponent systems, heterogeneous nitrogen oxide-particulate reactions, the generation and measurement of primary soot aerosols of size between 50 and 400 A, inertial particle size classification techniques, the design of air quality monitoring networks, visibilities in polluted and unpolluted areas, and monitoring air quality according to an ...
1980-01-01
A mobile remote sensing laboratory for water vapor, trace gas, aerosol, and wind speed measurements
Energy Technology Data Exchange (ETDEWEB)
The Lawrence Livermore National Laboratory has developed a mobile field laboratory for remote measurement of atmospheric processes and observables that are important in global climate change, dispersal of hazardous materials, and atmospheric pollution. Specific observables of interest are water vapor, trace gases, aerosol size and density, wind, and temperature. The goal is to study atmospheric processes continuously for extended periods in remote field locations. This laboratory has just reached field ready status with sensors for aerosol and trace gas measurement based on established techniques. A development program is underway to enhance the sensor suite with several new techniques and instruments that are expected to significantly extend the state of the art in remote trace gas analysis. The new sensors will be incorporated into the lab during the next two years.
1993-03-19
A Study on A Semi-Submersible Floating Offshore Wind Energy Conversion System
Energy Technology Data Exchange (ETDEWEB)
A new semi-submersible floating structure is proposed on which three wind turbine towers are installed. This paper presents a basic characteristic of the wave-induced motion of this semi-submersible floating structure via. numerical computations and 1/150 scaled rigid model experiments in a wave tank. In the numerical computations, nonlinear damping effect due to drag forces modeled by the Morison's formula is considered in the equation of motion, where the linear hydrodynamic forces are obtained from the Green's function model. As a result, the response characteristics around the resonant frequency region were successfully improved. In addition to such basic examination, major results of feasibility studies, including the structural stability for severe wave conditions and the long-term fatigue limit state, are presented for a realistic situation.
2007-07-01
Energy Technology Data Exchange (ETDEWEB)
Soils and food crops from a former tin mining location in a high background radiation area on the Jos-Plateau, Nigeria were collected and analyzed by gamma spectrometry to measure their contents of {sup 40}K, {sup 238}U and {sup 232}Th. As well as collecting samples, in situ dose rates on farms were measured using a precalibrated survey meter. Activity concentrations determined in food crops were compared with the local food derivatives or diets to investigate the possible removal or addition of radionuclides during food preparation by cooking or other means. Potassium-40 was found to contribute the highest activity in all the food products. The activity concentration of {sup 40}K, {sup 238}U and {sup 232}Th in local prepared diets ranged between 60 and 494 Bq kg{sup -1}, between BDL and 48 Bq kg{sup -1} and between BDL and 17 Bq kg{sup -1}, respectively. The internal effective dose to individuals from the consumption of the food types was estimated on the basis of ...
2007-04-15
International Nuclear Information System (INIS)
Soils and food crops from a former tin mining location in a high background radiation area on the Jos-Plateau, Nigeria were collected and analyzed by gamma spectrometry to measure their contents of "4"0K, "2"3"8U and "2"3"2Th. As well as collecting samples, in situ dose rates on farms were measured using a precalibrated survey meter. Activity concentrations determined in food crops were compared with the local food derivatives or diets to investigate the possible removal or addition of radionuclides during food preparation by cooking or other means. Potassium-40 was found to contribute the highest activity in all the food products. The activity concentration of "4"0K, "2"3"8U and "2"3"2Th in local prepared diets ranged between 60 and 494 Bq kg"-"1, between BDL and 48 Bq kg"-"1 and between BDL and 17 Bq kg"-"1, respectively. The internal effective dose to individuals from the consumption of the food types was estimated on the basis of the measured radionuclide ...
2007-04-01
Energy Technology Data Exchange (ETDEWEB)
Biomass is a potential source of energy that can reduce our dependency on oil as the main source of energy. In addition to municipal solid waste, animal and olive wastes are the main sources of organic waste in Jordan. In 2005, there were more than 2.4 million heads of sheep, about 72 thousand cows, and 40 million hens being raised in farms distributed in all governorates of Jordan. These animals produce 5.3 million tons (as exerted) of solid waste per year. If these quantities can be effectively collected they may constitute a valuable source of energy. This paper is aiming to estimate the amounts of animal and solid wastes generated in Jordan and their energy potential. The total amount of BOD from animal waste is estimated at 200,000 tons per year. Significant quantities of organic waste can also be collected from olive mills distributed in the country. This waste known locally as ''Jift'' is currently being collected and used ...
2010-10-15
The role of small and medium reactors in the energy security of a country, IRIS example
International Nuclear Information System (INIS)
Nuclear options for electricity generations are assessed in this paper. Probabilistic (stochastic) method is used for economic comparison of nuclear power plants, wind plants and natural gas fired plants. Optimal nuclear power plant size is also discussed. IRIS is presented as a representative of small and medium reactors
2009-05-26
The renaissance of solar homes; Le renouveau des maisons solaires
Energy Technology Data Exchange (ETDEWEB)
This publication of the Areva Group, a world nuclear industry leader, provides information on the energy in many domains. This issue deals with the nuclear fuel cycle, the biofuels, the everyday geothermal power, the Unites States energy supply and types, the Bertrand Picard solar aircraft, the kyoto protocol and the wind power leaders. A special chapter is devoted to the renaissance of solar homes. (A.L.B.)
2004-07-01
Energy Technology Data Exchange (ETDEWEB)
A review of theoretical and observational research on the magnetopause during 1987-1990. Starting with recent work on magnetic reconnection, the review proceeds to magnetopause surface wave phenomena, including the controversy over the role of solar wind pressure pulses in the coupling process and in the mimicking of flux transfer events signatures, and finishes with the magnetopause structure and associated wave phenomena. Recent advances in computer modeling of the magnetopause and the pertinent processes are also discussed. 108 refs.
1991-01-01
British Library Electronic Table of Contents (United Kingdom)
HOAI und Vergabe - erste Erfahrungen mit den Novellen 29. Stahlbauseminar INTAB+ Seminar 2010 Verbundbrucken mit integralen Widerlagern Hamburg Offshore Wind Conference 2010Perfect know-HOW Leichtbausysteme aus Stahl fur Dach und Fassade. Energie- und kosteneffiziente Losungen fur Neu- und Bestandsbau Lubecker Bautag
2010-01-01
Status report of the 17-M VAWT program
Energy Technology Data Exchange (ETDEWEB)
This report is directed at the commercial potential of the 17-m, 100 kW Darrieus Vertical Axis Wind Turbine (VAWT) developed under DOE funding by Sandia National laboratories (SNL) and Alcoa Laboratories. Three of the turbines have come on line over the past 14 months and long-term testing is in progress. As the first commercially adapted Darrieus turbines built by DOE, the superior cost, structural integrity, and output characteristics demonstrated by the prototypes appear particularly promising.
1981-01-01
Spin evolution in wind-fed X-ray binaries
International Nuclear Information System (INIS)
Global angular momentum balance suggests that the neutron stars in Be/X-ray binaries are not spinning in equilibrium. This requires an X-ray lifetime ''approx <'' 10"5 yr, and suggests that there are many 'dead' Be/X-ray binaries in the Galaxy. Some of these may be turned up as millisecond radio pulsars with Be star companions. (author).
Energy Technology Data Exchange (ETDEWEB)
This book comprises an up-to-date description of the astrophysical characteristics of the sun, including modern techniques used in solar research. Provides an historical background of solar research and techniques and covers the necessary astrophysics for solar studies, energy generation in the interior, the convection zone, the non- thermally heated layers, and solar wind are described in detail. Also considers the sun in relation to other stars, including information on its variable outputs of light, charged particles, and fields.
1990-01-01
International Nuclear Information System (INIS)
The implementation of wind energy conversion systems in the built environment renewed the interest and the research on Vertical Axis Wind Turbines (VAWT), which in this application present several advantages over Horizontal Axis Wind Turbines (HAWT). The VAWT has an inherent unsteady aerodynamic behavior due to the variation of angle of attack with the angle of rotation, perceived velocity and consequentially Reynolds number. The phenomenon of dynamic stall is then an intrinsic effect of the operation of a Vertical Axis Wind Turbine at low tip speed ratios, having a significant impact in both loads and power. The complexity of the unsteady aerodynamics of the VAWT makes it extremely attractive to be analyzed using Computational Fluid Dynamics (CFD) models, where an approximation of the continuity and momentum equations of the Navier-Stokes equations set is solved. The complexity of the problem and the ...
2007-07-01
International Nuclear Information System (INIS)
Energy policy is discussed, with particular reference to Scotland. The plans for nuclear power are analyzed in comparison with developments in coal mining, use of oil and gas and other possible energy sources such as wind and wave power. Arguments against the development of nuclear power are raised on grounds of economics, employment potential, and problems of waste disposal. (U.K.).
1979-03-01
Revegetation of inactive U-tailing sites
International Nuclear Information System (INIS)
Soil placed over any sealant/barrier system can provide a protective mantle if the soil is not lost by erosion. Vegetation is an attractive choice for controlling erosion because it can provide an economical self-renewing cover that serves to reduce erosion by both wind and water. The objective of this research and development effort is to select and test vegetation strategies, including the choice of species and methods for revegetation that are compatible with sealant/barrier systems and are suited to soils and climates at inactive uranium mill tailings sites.
1981-02-01
International Nuclear Information System (INIS)
This short article describes the strategies taken into consideration by the Swiss Federal Office of Energy for the promotion of renewable forms of energy in Switzerland. Two basic models are considered and the parts to be played by the Swiss Confederation, the Swiss Cantons, Energy Agencies and professional organisations are discussed. The importance of the activities of partner organisations and actor-networks in various areas such as solar, small hydro, geothermal and wind energy are discussed, as are models for financing the necessary promotion and marketing efforts
Progress of magnetic-suspension systems and magnetic bearings in the USSR
International Nuclear Information System (INIS)
This paper traces the development and progress of magnetic suspension systems and magnetic bearings in the USSR. The paper describes magnetic bearings for turbomachines, magnetic suspension systems for vibration isolation, some special measuring devices, wind tunnels, and other applications. The design, principles of operation, and dynamic characteristics of the system are presented.
1992-05-01
Energy Technology Data Exchange (ETDEWEB)
Blade fatigue life is an important element in determining the economic viability of the Vertical-Axis Wind Turbine (VAWT). A principal source of blade fatigue is thought to be the stochastic (i.e., random) aerodynamic loads created by atmospheric turbulence. This report describes the theoretical background of the VAWT Stochastic Aerodynamic Loads (VAWT-SAL) computer code, whose purpose is to numerically simulate these random loads, given the rotor geometry, operating conditions, and assumed turbulence properties. A Double-Multiple-Stream Tube (DMST) analysis is employed to model the rotor's aerodynamic response. The analysis includes the effects of Reynolds number variations, different airfoil sections and chord lengths along the blade span, and an empirical model for dynamic stall effects. The mean ambient wind is assumed to have a shear profile which is described by either a power law or a logarithmic variation with height above ...
1991-09-01
Energy Technology Data Exchange (ETDEWEB)
Nexans has developed a new type of high voltage sea cable with metal barrier for dynamic application, suited for floating installations such as vessels, floating wind turbines or floating platforms. A brief presentation of the cable's design (ml)
2007-07-01
International Symposium on Magnetic Suspension Technology. Part 2
International Nuclear Information System (INIS)
In order to examine the state of technology of all areas of magnetic suspension and to review related recent developments in sensors and controls approaches, superconducting magnet technology, and design/implementation practices, a symposium was held. The proceedings are presented. The sessions covered the areas of bearings, sensors and controls, microgravity and vibration isolation, superconductivity, manufacturing applications, wind tunnel magnetic suspension systems, magnetically levitated trains (MAGLEV), space applications, and large gap magnetic suspension systems.
1991-08-19
Energy Technology Data Exchange (ETDEWEB)
Assessing the potential environmental and human effects of deploying renewable energy on private and public lands, along our coasts, on the Outer Continental Shelf (OCS), and in the Great Lakes requires a new way of evaluating potential environmental and human impacts. The author argues that deployment of renewables requires a framework risk paradigm that underpins effective future siting decisions and public policies.
2010-04-01
Implementation of Renewable Energy Systems in Denmark
DEFF Research Database (Denmark)
Denmark has been one of the first countries in the world to commit itself to a sustainable energy development. This has been substantiated by two official action plans from 1990 and 1996 with emphasis on energy efficiency and supply systems based on renewable energy. In year 2005, renewable energy sources are planned to cover 12-14% and in year 2030 about 35% of total Danish energy demand. This paper reviews the experiences with implementation of renewable energy in Denmark with a focus on wind power and biomass.
1997-01-01
Guide to UK renewable energy companies 2001. 6. ed.
International Nuclear Information System (INIS)
This 2001 edition of the guide to UK renewable companies and equipment and service providers presents summaries of the different industry sectors covering wind power, photovoltaics, solar water heating, geothermal heat pump, hydroelectric power, marine current and wave technology, bioenergy, power generation from landfill gas, energy from waste, and cogeneration. A UK company classification listing and index is provided along with listing of UK organisations and companies and an index of advertisers.
Glacial geology of the West Tensleep Drainage Basin, Bighorn Mountains, Wyoming
Energy Technology Data Exchange (ETDEWEB)
The glacial deposits of the West Tensleep Basin in the Bighorn Mountains of Wyoming are mapped and a relative chromology established. The deposits are correlated with the regional model as defined in the Wind River Mountains. A statistical analysis is performed on the density and weathering characteristics of the surficial boulders to determine their validity as indicators of relative age. (ACR)
1980-08-01
Geothermal resources of the Wind River Basin, Wyoming
Energy Technology Data Exchange (ETDEWEB)
The geothermal resources of the Wind River Basin were investigated. Oil-well bottom-hole temperatures, thermal logs of wells, and heat flow data have been interpreted within a framework of geologic and hydrologic constraints. Basic thermal data, which includes the background thermal gradient and the highest recorded temperature and corresponding depth for each basin, is tabulated. Background heat flow in the Wind River Basin is generally insufficient to produce high conductive gradients. Only where hydrologic systems re-distribute heat through mass movement of water will high temperatures occur at shallow depths. Aquifers which may have the confinement and structural characteristics necessary to create such geothermal systems are the Lance/Fort Union, Mesa Verde, Frontier, Muddy, Cloverly, Sundance, Nugget, Park City, Tensleep, Amsden, Madison, Bighorn, and Flathead Formations. Of these the Tensleep Sandstone and Madison Limestone are the most ...
1985-01-01
Flexible DER Utility Interface System: Final Report, September 2004--May 2006
Energy Technology Data Exchange (ETDEWEB)
In an effort to accelerate deployment of Distributed Energy Resources (DER) such as wind, solar, and conventional backup generators to our nation's electrical grid, Northern Power Systems (NPS), the California Energy Commission (CEC), and the National Renewable Energy Laboratory (NREL) collaborated to create a prototype universal interconnect device called the DER Switch.
2006-08-01
Energy storage for hybrid remote power systems
Energy Technology Data Exchange (ETDEWEB)
Energy storage can be a cost-effective component of hybrid remote power systems. Storage serves the special role of taking advantage of intermittent renewable power sources. Traditionally this role has been played by lead-acid batteries, which have high life-cycle costs and pose special disposal problems. Hydrogen or zinc-air storage technologies can reduce life-cycle costs and environmental impacts. Using projected data for advanced energy storage technologies, LLNL ran an optimization for a hypothetical Arctic community with a reasonable wind resource (average wind speed 8 m/s). These simulations showed the life-cycle annualized cost of the total energy system (electric plus space heating) might be reduced by nearly 40% simply by adding wind power to the diesel system. An additional 20 to 40% of the wind-diesel cost might be saved by adding hydrogen storage or zinc-air fuel cells to the system. ...
1998-03-01
Energy Technology Data Exchange (ETDEWEB)
This paper shows a computerized system, that adopt a statistical methodology and simultaneous measurements of wind velocity and environment temperature, as an experiences at the power transmission lines with environmental monitoring systems. 9 figs., 16 refs.
1991-12-31
Energy Technology Data Exchange (ETDEWEB)
''Climates of the Oceans'' deals with the atmosphere over the world oceans and provides a treatment not only of the climatic elements such as temperature, pressure, wind, precipitation etc., but also of the circulation of the atmosphere and its changes throughout the year. The connection between sea and overlying air is examined through studies of the water and heat balance. Numerous maps and tables illustrate the elements and their fluctuations over the water and on islands and coasts.
1984-01-01
Bounding ingestion stream-tube determination via a CO tracer
Energy Technology Data Exchange (ETDEWEB)
A gas tracer technique based on carbon monoxide and a commercial automotive exhaust gas analyser has been applied to wind tunnel models of waterjet propulsion systems intakes. The post-processing and interpretation of the carbon monoxide concentration signals has yielded high resolution measurements of the bounding ingestion stream-tubes. (orig.) With 3 figs., 1 tab., 8 refs.
1998-05-01
During the erection of the Sandia 34-Meter VAWT Test Bed, the induced gravitational stress state in the turbine blades and their associated deflections were measured. This manuscript details the measurements that were taken on the Test Bed blades during erection and compares them to the stresses and deflections predicted by the NASTRAN finite element code.
1987-01-01
The genesis solar-wind sample return mission
Energy Technology Data Exchange (ETDEWEB)
The compositions of the Earth's crust and mantle, and those of the Moon and Mars, are relatively well known both isotopically and elementally. The same is true of our knowledge of the asteroid belt composition, based on meteorite analyses. Remote measurements of Venus, the Jovian atmosphere, and the outer planet moons, have provided some estimates of their compositions. The Sun constitutes a large majority, > 99%, of all the matter in the solar system. The elemental composition of the photosphere, the visible 'surface' of the Sun, is constrained by absorption lines produced by particles above the surface. Abundances for many elements are reported to the {+-}10 or 20% accuracy level. However, the abundances of other important elements, such as neon, cannot be determined in this way due to a relative lack of atomic states at low excitation energies. Additionally and most importantly, the isotopic composition of the Sun cannot be determined astronomically ...
2009-01-01
The establishment of the Danish windmill industry - was it worthwhile?
Energy Technology Data Exchange (ETDEWEB)
The renewed interest for using wind energy commercially is not more than twenty-five years old. From an experimental stage of turning wind energy into electricity in the 1970s, a new industry for producing standardised windmills gained foothold in the beginning of the 1980s and since then it has developed rapidly through the 1980s and the 1990s. The Danish innovators of the new windmill technology have been the pioneers behind this development, and Denmark has succeeded in acquiring a first mover advantage on the world market. This position has been maintained and at present Denmark satisfies more than half of the world market's demand for windmills. There are at least two reasons for this pioneering position of the Danish windmill industry. First, Denmark is by nature very `abundant' in wind energy due to its geographical position at the nexus between the Gulf Stream and the European continent. The windy ...
2002-07-01
The establishment of the Danish windmill industry - was it worthwhile?
International Nuclear Information System (INIS)
The renewed interest for using wind energy commercially is not more than twenty-five years old. From an experimental stage of turning wind energy into electricity in the 1970s, a new industry for producing standardised windmills gained foothold in the beginning of the 1980s and since then it has developed rapidly through the 1980s and the 1990s. The Danish innovators of the new windmill technology have been the pioneers behind this development, and Denmark has succeeded in acquiring a first mover advantage on the world market. This position has been maintained and at present Denmark satisfies more than half of the world market's demand for windmills. There are at least two reasons for this pioneering position of the Danish windmill industry. First, Denmark is by nature very 'abundant' in wind energy due to its geographical position at the nexus between the Gulf Stream and the European continent. The windy climate makes ...
Energy Technology Data Exchange (ETDEWEB)
This report describes and analyzes renewable energy seen as emerging markets, focusing on wind, solar and wave power. The conclusions are that: Wind and solar energy has reached critical mass. They are already large markets, and has a high growth rate. There are growth areas that may become among the world's largest industries in the future. This summary report and the underlying studies of wind, solar and wave power show that there is a large potential market for renewable energy sources. Wind power is already a market worth around 36.5 billion Euro. Solar energy is growing strongly and solar cells in 2008 had a market worth around 24 billion Euro. Wave power is at present a very small market and the in the actual development stage the potential of wave power is uncertain. But if the wave would become commercially viable, it could represent a significant part of the world's energy ...
2009-03-15
Valuing climate protection through willingness to pay for biomass ethanol
Energy Technology Data Exchange (ETDEWEB)
This study uses a multi-part, split-sample contingent valuation method (CVM) and fair share (FS) survey to better understand the public's valuation of mitigating global climate change through its willingness to pay for biomass or 'cellulosic' ethanol. In addition to a basic CVM question, a related scenario was developed that asked half of the survey respondents to state their fair share cost to lessen a potential food shortage in the next decade, also through the expanded use of cellulosic ethanol. Three alternative biomass feedstocks were assessed: farming residues, forestry residues and paper mill wastes, and municipal solid wastes. Overall a slightly larger proportion of respondents were WTP extra for cellulosic ethanol in the basic CVM scenario than in the FS scenario, though no significant differences were found in the WTP for the different feedstocks. Bid curve lognormal regression results for the two models were similar, supporting ...
2009-05-15
Energy Technology Data Exchange (ETDEWEB)
Water protection wetlands aim to reduce nitrogen and phosphorous concentrations either separately or simultaneously. In the latter case, a wetland must contain parts differing clearly in both function and physical condition. In efforts to reduce nitrogen the most important process is denitrification. Phosphorus is deposited with solids and bound to the vegetation and soil in wetlands. As the bulk of the solid and nutrient load comes from catchments during spring floods, wetlands should be designed on the basis of, at least, the average maximum vernal run-off (MHq). Use of higher run-offs, e.g. MHql/10 or MHql/20, in the design without reducing the target retention would require large wetlands. The efficiency of wetlands is constrained by too short retention times and low leachate temperatures. Wetlands established with special environmental support are normally designed on the basis of MHq. The average catchment area of such wetlands is 1.86 km{sup 2} median 0.53 km{sup 2}. The ...
1998-12-31
International Nuclear Information System (INIS)
The outcome was retrospectively examined and prognostic factors were discussed for arterial chemo-infusion therapy (ACT) through an implanted reservoir system and radiation therapy (RT) in patients with unresectable intrahepatic cholangiocarcinoma (CCC). ACT plus RT were conducted to 25 patients (mean age 61.7 y, M/F 12/13, stage III-IVB) during 10 years from 1996 to 2005 with various regimens of cisplatin (CDDP), 5- fluorouracil (FU), epirubicin (FARM), mitomycin C (MMC) plus 39-50 Gy of radiation in a fractionated manner partly involving internal RT (2 cases, 15 Gy) and RT for metastatic bone (1, 25 Gy). The survival rates at 1, 2 and 3 years after ACT+RT were respectively 52.5, 43.7 and 28.1%; total efficacy (PR) was 36% (9/25) at 6 months; and significantly good prognostic factors were found to be female and absence of metastasis remote and/or lymphatic around artery. Authors concluded that ACT+RT was a meaningful treatment for highly advanced non-respectable ...
2007-11-01
International Nuclear Information System (INIS)
Reproductive parameters were monitored in 50 post-partum Bos indicus x Bos taurus animals located on four farms in two ecological zones of Panama. Progesterone (P_4) concentrations were measured in four of these animals twice a week and their reproductive organs palpated per rectum once a week until 60 days post-artificial-insemination or post-natural-service. The other 46 cows were palpated for early pregnancy between days 45 and 60 post-service. The mean P_4 concentration in cows with palpable corpora lutea (CL) was 10.3#+-#4.0 nmol/L; when no Cl were detected, the mean P_4 level was 2.2#+-#1.6 nmol/L. Of the 46 animals palpated for early pregnancy, 36 (70%) were found to be pregnant, one (2%) exhibited early embryonic death and one (2%) aborted; the other eight cows (17%) were anoestrous. The mean P_4 concentration in pregnant cows was 11.9#+-#4.0 nmol/L and the calving to conception interval was 148 days. (author). 13 refs, 7 figs, 4 tabs.
Energy Technology Data Exchange (ETDEWEB)
Biogas, produced from anaerobic digestion of organic matter in domestic, industrial and rural wastewaters and residuals, represent an alternative and renewable source of energy, with growing use worldwide. In Brazil, high population and its spatial concentration and expressive agricultural and agricultural-industrial production indicate a substantial potential of biogas production. The results presented in this work show a potential of biogas production of almost 2 billion cubic feet a day of CH{sub 4}. Viability of biogas production and use depends substantially on project scale. Generally, biogas projects are viable from landfills and domestic wastewater treatment for populations higher than 50,000 inhabitants and swine and dairy farms with at least 5,000 and 1,000 animals, respectively. Biogas is also competitive when compared to fossil fuels used in industry and transport. Despite incentive mechanisms for biogas production and use, like Clean Development ...
2009-12-15
Energy Technology Data Exchange (ETDEWEB)
This report is a summary of the contribution of nitrogen and phosphorus in the eutrophication process of inland and coastal waters. Special attention was paid to the mechanisms of these nutrients in regulating biological processes and to the methods available in estimating their effects in the eutrophication of water bodies. The report includes five chapters which are entitled: Introduction, which is a general background to the subject with special attention to the requirements of the Finnish Water Act. Phosphorus and nitrogen as factors regulating biological processes. The topics included are: definition of eutrophication, forms of phosphorus and nitrogen and their sources to inland and coastal waters, effects of these nutrients as growth factors of phytoplankton and macrophytes and consequences of eutrophication. Estimation of the effects of phosphorus and nitrogen. The topics discussed from the point of view of the tasks of the National Board of Waters and the Environment are: ...
1992-01-01
Energy Technology Data Exchange (ETDEWEB)
Five corrosion probes were received from West Valley Nuclear Services for evaluation in simulated tank 8D-2 3rd-stage sludge wash slurry. The same waste slurry simulated was also used in a series of ongoing corrosion studies assessing the effects of in-tank sludge washing on the integrity of tank 8D-2. Two of the corrosion probes were installed in the coupon corrosion test vessels operating at {approximately}150{degrees}F to compare performance of the probes with that observed by coupon tests conducted in the same vessels. Corrosion rate data calculated from electrical resistance measurements of the corrosion probes were evaluated for this study using two slightly different approaches. One approach uses the total length of exposure of the probe to give a ``time-averaged`` value of the corrosion rate. The other approach uses a shorter period of time (relative to the length of the test) in the calculation of corrosion rate, and is referred to as the ``instantaneous`` rate. The ...
1994-07-01
Energy Technology Data Exchange (ETDEWEB)
This guide explained the requirements for Off-Road Compression Ignition Engine Emission Regulations established under the Canadian Environmental Protection Act. The regulations are enforced by Environment Canada, which authorizes and monitors the use of the national emissions mark. The regulations prescribe standards for off-road engines that operate as reciprocating, internal combustion engines, other than those that operate under characteristics similar to the Otto combustion cycle and that use a spark plug or other sparking device. The regulations apply to engines that are typically diesel-fuelled and found in construction, mining, farming and forestry machines such as tractors, excavators and log skidders. Four different types of persons are potentially affected by the regulations: Canadian engine manufacturers; distributors of Canadian engines or machines containing Canadian engines; importers of engines or machines for the purpose of sale; and persons not in ...
2006-03-15
International Nuclear Information System (INIS)
This guide explained the requirements for Off-Road Compression Ignition Engine Emission Regulations established under the Canadian Environmental Protection Act. The regulations are enforced by Environment Canada, which authorizes and monitors the use of the national emissions mark. The regulations prescribe standards for off-road engines that operate as reciprocating, internal combustion engines, other than those that operate under characteristics similar to the Otto combustion cycle and that use a spark plug or other sparking device. The regulations apply to engines that are typically diesel-fuelled and found in construction, mining, farming and forestry machines such as tractors, excavators and log skidders. Four different types of persons are potentially affected by the regulations: Canadian engine manufacturers; distributors of Canadian engines or machines containing Canadian engines; importers of engines or machines for the purpose of sale; and persons not in ...
1999-01-01
Energy Technology Data Exchange (ETDEWEB)
The purpose of this report is to summarize the assumptions, dose factors, consumption rates, and methodology used to evaluate potential radiation doses to persons who may eat contaminated wildlife or contaminated plants collected from the Hanford Site. This report includes a description of the number and variety of wildlife and edible plants on the Hanford Site, methods for estimation of the quantities of these items consumed and conversion of intake of radionuclides to radiation doses, and example calculations of radiation doses from consumption of plants and wildlife. Edible plants on the publicly accessible margins of the shoreline of the Hanford Site and Wildlife that move offsite are potential sources of contaminated food for the general public. Calculations of potential radiation doses from consumption of agricultural plants and farm animal products are made routinely and reported annually for those produced offsite, using information about concentrations of ...
1990-10-01
Integrated risk analysis of a heavy-metal-contaminated site in Taiwan
Energy Technology Data Exchange (ETDEWEB)
The Love Canal episode began the long battle on hazardous wastes in the United States. Obviously, the potential danger of hazardous wastes is one of the hottest issues among environmental professionals as well as the public. The problems of hazardous wastes in economically booming Taiwan are also alarming. Several farmlands in northern Taiwan were contaminated heavily by industrial effluents containing heavy metals (cadmium and lead) in the early 1980s. Regardless of the many studies that have been conducted about these polluted farmlands, there has not been any remediation - just a passive abandonment of farming activities with minimal compensation. This paper addresses a heavy-metal-contaminated fanning area. A pollution profile across time is delineated using information from the abundance of reports, and the contamination is modeled mathematically. The past, the present, and future exposures are also modeled. The results are presented in terms of societal ...
1996-12-31
Influence of nutrition and suckling patterns on the postpartum cyclic activity of swamp buffaloes
International Nuclear Information System (INIS)
Two studies were conducted to investigate the effects of nutrition and suckling patterns on the ovarian cyclicity of postpartum buffaloes. In Study 1, which was conducted on an institutional farm, two different diets were fed to 24 buffaloes during late gestation and postpartum period. Restricted (twice daily) suckling began on day 30 postpartum in half the animals on each diet. The body weight of both ad libitum suckled and twice daily suckled groups declined during the postpartum period, irrespective of the diet fed. Buffaloes subjected to restricted suckling lost less body weight and re-established ovarian cyclicity earlier than those suckled ad libitum. In Study 2, which was conducted under village conditions, temporary calf removal for 72 hours on days 91-93 postpartum in anoestrous buffaloes induced the re-establishment of ovarian cyclicity within 14 days. (author). 11 refs, 7 tabs.
1989-02-20
ICPP water inventory study project summary report
Energy Technology Data Exchange (ETDEWEB)
The Idaho Chemical Processing Plant (ICPP) Water inventory Study was initiated in September 1993 with the formation of a joint working group consisting of representatives from DOE-ID, State of Idaho INEL Oversight Program, US Geological Survey, and INEL employees to investigate three issues that had been identified by the INEL Oversight Program at ICPP: (1) the water inventory imbalance at ICPP, (2) the source of water infiltrating into the Tank Farm vault sumps, and (3) the source of water providing potential recharge to perched water bodies underlying ICPP. These issues suggested that water was being lost from the ICPP distribution system. The INEL Oversight Program was concerned that the unaccounted for water at ICPP could be spreading contaminants that have been released over the past 40 years of operations of ICPP, possibly to the Snake River Plain Aquifer. This report summarizes the findings of each of the component investigations that were undertaken to ...
1994-01-01
Energy Technology Data Exchange (ETDEWEB)
Waste Management Area U (WMA U) includes the U Tank Farm, is currently regulated under RCRA interim-status regulations, and is scheduled for closure probably post-2030. Groundwater monitoring has been under an evaluation program that compared general contaminant indicator parameters from downgradient wells to background values established from upgradient wells. One of the indicator parameters, specific conductance, exceeded its background value in one downgradient well triggering a change from detection monitoring to a groundwater quality assessment program. The objective of the first phase of this assessment program is to determine whether the increased concentrations of nitrate and chromium in groundwater are from WMA U or from an upgradient source. Based on the results of the first determination, if WMA U is not the source of contamination, then the site will revert to detection monitoring. If WMA U is the source, then a second part of the groundwater quality ...
2000-03-21
Failure of monsoon this year has been linked to the El Nino effect. What is this phenomenon
Energy Technology Data Exchange (ETDEWEB)
There are two major water currents off the coast of Peru in South America. The Humboldt or Peru current travels northwest across latitudes 35/sup 0/S to 6/sup 0/S. To the north, a branch of the equatorial current flows southward down to latitudes 6-7/sup 0/S in normal years. Its warm, less salty water is poor in nutrients and cannot support fishery. In some years, this warm current extends much more southward, down to 12/sup 0/S. This has a catastrophic effect leading to a mass mortality of the anchovies and, in turn, of the guano birds and less production of farm crops. This phenomenon occurs around Christmas (summer in the southern hemisphere) and is, therefore, called El Nino. The main feature of El Nino is to change the sea surface temperature. An abnormal rise in sea surface temperature can give rise to odd air movements which can change the monsoons pattern, even at distant places, profoundly. In the past 26 years, when El Ninos have occurred, they coincided ...
1987-10-01
Evaluation of some lupin mutants under different irrigation intervals and nitrogen fertilizer levels
International Nuclear Information System (INIS)
This investigation was carried out during the two seasons of 1998/1999 and 1999/2000 at the experimental farm belonging to the plant research department, nuclear research center, atomic energy authority in Inshas to evaluate four lupin mutant lines (L_1, L_2, L_3 and L_4) along with their original mother varieties giza 1 and giza 2 under different levels and nitrogen fertilizer levels. The results indicated that seed yield/ plant and its effective components number and weight of pods/plant were significantly higher in all the mutant lines as compared to their parents either in the first or second seasons. Concerning the effect of irrigation intervals on yield and its components for developed mutants and their mother varieties as well as the results gave an evidence that the wider interval showed the lesser values for yield and most of yield components. Obtained data also revealed that yield attributes of lupin mutants and their parents were affected by applying ...
2002-04-01
British Library Electronic Table of Contents (United Kingdom)
A field experiment was conducted during 2004 and 2005 at the research farm of Central Institute of Medicinal And Aromatic Plants, Lucknow located at 26.5^o N 80.5^o E and 120m above the mean sea level to study the effect of harvesting stage and cutting height on growth, yield and quality of Indian basil. The objective of this study was to increase the essential oil yield of Indian basil without adverse effect on quality by taking two harvests through manipulating harvesting stage and cutting height and to increase the land and rain water utilization efficiency under rain fed condition. The treatments consisted of four stages of first harvest (40, 60, 80 and 100 days after transplanting (DAT)) and three cutting height (0, 7.5 and 15.0cm above ground level). The Indian basil (Ocimum basilicu...
2010-01-01
Biomass research program of the USDA Southern Agricultural Energy Center
Energy Technology Data Exchange (ETDEWEB)
The biomass research program of the USDA, Southern Agricultural Energy Center is conducted at several locations throughout the United States. A portion of the research is directed toward improved systems to harvest, process and store biomass so that the energy density will be enhanced. Other research projects deal with: conversion and utilization of animal wastes in integrated energy-food production systems, including the production of liquid fuel and feed byproducts; producing low BTU gas to be utilized in internal combustion engines, including the system for continuous feeding of the gasifier; direct combustion of biomass for thermal energy; gasifying biomass so that the products of combustion can pass through a crop being dried without leaving deleterious residues; small scale systems for on-farm expelling of vegetable oil; and studies on the use of vegetable oils for diesel fuel substitutes. In summary, the low energy density of biomass requires that it be used ...
1982-08-01
Biodrying of animal slaughterhouse residues and heat production
Energy Technology Data Exchange (ETDEWEB)
Animal carcasses from slaughterhouses are usually composted on farms, but the composting process is not optimized and a large volumes of carbonaceous residues are needed. This type of composting takes place over a period of 6 to 9 months in a nonaerated static pile. Quebec's industrial research centre (CRIQ) developed an organic biodrying process (BIOSECO) adapted to large-scale operations in order to optimize the treatment of slaughterhouse residues. Biodrying is a form of composting, in which the thermophilic phase is optimized, making it possible to evaporate large amounts of water. Biodrying is done inside a building and reduces the amount of carbonaceous residues considerably. The process is optimized by the sequence in which the slaughterhouse residues are added, the choice of input and the aeration flow. Slaughterhouse residues can be treated non-stop throughout the entire year. Since the odours are nearly completed limited to the building, the ...
2010-07-01
Anaerobic digestion and related best management practices : utilizing life cycle assessment
Energy Technology Data Exchange (ETDEWEB)
This paper reported on a life cycle assessment (LCA) study that compared the environmental impacts of business-as-usual manure management with those of a manure management operation incorporating anaerobic digestion with combined heat and power generation. The case study was based on a medium sized dairy farm in northern New York State. The study identified the benefits resulting from the displacement of fossil fuels, and reduction of related emissions. Although anaerobic digestion of dairy manure with energy recovery through biogas combustion is viewed as a positive environmental approach to increase the use of renewable energy, there are potential negative impacts that can counteract the environmental benefits. The negative impacts are associated with emissions of methane and nitrogen species during digestion and after spreading of digester effluent. The environmental impacts and their causes should be evaluated in order to promote best management practices. ...
2010-07-01
Energy Technology Data Exchange (ETDEWEB)
The aim of this research was to examine the energy equivalents of inputs and output in greenhouse vegetable production in the Antalya province of Turkey. For this purpose, the data for the production of four greenhouse crops (tomato, cucumber, eggplant and pepper) were collected in eighty-eight greenhouse farms by questionnaire. The results revealed that cucumber production was the most energy intensive of among the four crops investigated. Cucumber production consumed a total of 134.77 GJha{sup -1} followed by tomato with 127.32 GJha{sup -1}. The consumption of energy by eggplants and pepper were 98.68 and 80.25 GJha{sup -1}, respectively. The output-input energy ratio for greenhouse tomato, pepper, cucumber and eggplant were estimated to be 1.26, 0.99, 0.76 and 0.61, respectively. This indicated an intensive use of inputs in greenhouse vegetable production not accompanied by increase in the final product. This can lead to problems associated with these inputs ...
2004-01-01
An anthropological view of the forest culture of Peten, Guatemala
Energy Technology Data Exchange (ETDEWEB)
Traditional farmers and harvesters of non-timber forest products in Peten treat the forest in ways that conserve and regenerate its resources. They believe no one owns the forest outright. Humans share it with other life forms and therefore no one has the right to monopolize or destroy forest resources. Traditional Peteneros find a use for almost everything in the forest, and believe it neither smart nor proper to use a given area for a single purpose, for example, to clear an area of all trees and devote it exclusively to a cattle pasture. In the traditional system most medicinal plants, basic foodstuffs, fuelwoods and construction materials are taken from the bosque (secondary forests within walking distance of human settlements). Peteneros` sustainable use of bosques eases pressure on the monte (primary forests). In the monte Peteneros` harvesting practices are protective of resources, causing minimal damage. Finding almost everything in the forest useful, Peteneros believe all ...
1995-12-31
WR 104: Are We Looking Down The Gun Barrel of a Future GRB?
WR 104 is the prototype for a small but growing group of stars that present the remarkably striking appearance of pinwheels. High resolution images of WR 104 show the (apparently) face-on spiral turning with an 8 month period. The pinwheel is assumed to be composed of dust produced via colliding winds in a low-inclination WR+OB binary. These assumptions have been very successful in modeling the imaging, but remain largely untested by spectroscopy. Strong motivation for further study of this system has emerged. Recent theory suggests that some gamma-ray bursts (GRB's) are core-collapse supernovae viewed nearly pole-on. The WC class Wolf-Rayet star in WR 104 is the type of star thought to be a possible GRB progenitor. If the orbit (and thus stellar rotation axes) are pole-on, the effects on Earth's biosphere could be significant. Confrontation of the face-on colliding-wind binary model with eight years of spectroscopy, offering full phase ...
2009-01-01
Visualization study on the static flow field around a straight-bladed vertical axis wind turbine
Visual experiments based on the smoke wire way were carried out on a small model of Straight-blade Vertical Axis Wind Turbine (SB-VAWT) to invest the relationship between the static flow field characteristics and the rotor azimuth angle. The test rotor had 3 blades with NACA0018 aerofoil. The rotor diameter and blade chord were 0.3m and 0.07m, respectively. Visual photos of the static flow path lines in and around the rotor were obtained at every 5 degrees of the azimuth angle. Further, numerical computations of the static flow filed were also carried out for comparison with the same situation as the visual tests and the static torques at different azimuth angles were calculated. According to the results of visual tests and computations, the dependence of the starting performance on the azimuth angle was discussed. The solidity is an important factor affecting the starting performance of the SB-VAWT.
2009-12-01
Using ERS-2 SAR images for routine observation of marine pollution in European coastal waters
Energy Technology Data Exchange (ETDEWEB)
More than 660 synthetic aperture radar (SAR) images acquired over the southern Baltic Sea, the North Sea, and the Gulf of Lyon in the Mediterranean Sea by the Second European Remote Sensing Satellite (ERS-2) have been analyzed since December 1996 with respect to radar signatures of marine pollution and other phenomena causing similar signatures. First results of our analysis reveal that the seas are most polluted along the main shipping routes. SAR images acquired during descending (morning) and ascending (evening) satellite passes show different percentages of oil pollution, because most of this pollution occurs during night time and is still visible on the SAR images acquired in the morning time. Moreover, we found a higher amount of oil spills on SAR images acquired during summer (April-September) than on SAR images acquired during winter (October-March). We attribute this finding to the higher mean wind speed encountered in all three test areas during winter. ...
1999-09-30
Things fall apart: topology change from winding tachyons
Energy Technology Data Exchange (ETDEWEB)
We argue that closed string tachyons drive two spacetime topology changing transitions - loss of genus in a Riemann surface and separation of a Riemann surface into two components. The tachyons of interest are localized versions of Scherk-Schwarz winding string tachyons arising on Riemann surfaces in regions of moduli space where string-scale tubes develop. Spacetime and world-sheet renormalization group analyses provide strong evidence that the decay of these tachyons removes a portion of the spacetime, splitting the tube into two pieces. We address the fate of the gauge fields and charges lost in the process, generalize it to situations with weak flux backgrounds, and use this process to study the type 0 tachyon, providing further evidence that its decay drives the theory sub-critical. Finally, we discuss the time-dependent dynamics of this topology-changing transition and find that it can occur more efficiently than analogous transitions on extended ...
2005-10-15
Things Fall Apart: Topology Change From Winding Tachyons
Energy Technology Data Exchange (ETDEWEB)
We argue that closed string tachyons drive two spacetime topology changing transitions--loss of genus in a Riemann surface and separation of a Riemann surface into two components. The tachyons of interest are localized versions of Scherk-Schwarz winding string tachyons arising on Riemann surfaces in regions of moduli space where string-scale tubes develop. Spacetime and world-sheet renormalization group analyses provide strong evidence that the decay of these tachyons removes a portion of the spacetime, splitting the tube into two pieces. We address the fate of the gauge fields and charges lost in the process, generalize it to situations with weak flux backgrounds, and use this process to study the type 0 tachyon, providing further evidence that its decay drives the theory sub-critical. Finally, we discuss the time-dependent dynamics of this topology-changing transition and find that it can occur more efficiently than analogous transitions on extended ...
2005-02-04
The most effective procurement mechanism for wind energy
Energy Technology Data Exchange (ETDEWEB)
This presentation discussed common mechanisms for procuring wind energy in Canada. Mechanisms included renewable portfolio standards (RPSs); offsets; tax subsidies; financial subsidies; command and control mechanisms; and request for proposals (RFPs). A layered approach is required to avoid reliance on any single mechanism. RPSs require a certain minimum percentage of energy to come from renewable sources and aim to encourage the local development of renewable energy. RPSs are market-friendly and often result in the creation of tradable renewable energy credits (RECs) used for compliance purposes. RPSs work in parallel with cap and trade, baseline, and credit and carbon tax systems. RFPs target the lowest price offering, a practice which has often resulted in lower rates of return, high attrition, and a failure to attribute market prices to green attributes. It was concluded that RPSs work with a variety of policy frameworks and encourage the development of ...
2008-07-01
The effect of welding parameters on hydrogen distribution in pipeline welds
Energy Technology Data Exchange (ETDEWEB)
There is currently considerable interest in identifying and quantifying the effects of welding procedure parameters and steel composition factors on the risk of cracking in pipeline girth welds that may be experienced during winter construction. Although low ambient temperatures, that may be experienced during winter construction, are generally assumed to increase the risk of cracking there has been little work to quantify the effects and to suggest how welding procedures should be modified for winter conditions. The present work was undertaken to calculate the effects of changes in welding parameters on the thermal cycle and the diffusion of hydrogen for a typical pipeline girth weld. A simple analytical method and the finite element method (FEM) were used. Both methods gave similar results but the simple method was very sensitive to the value of heat transfer coefficient. The results showed that the relation between the hydrogen diffusion parameter (tau) and cooling time S{sub ...
1990-03-01
Energy Technology Data Exchange (ETDEWEB)
As an interim report on the study on vibration of transmission lines when gust is blowing, this paper introduces events of confused and other contacts between transmission lines, photographing of transmission line vibration, physical measurement on transmission line response, and development of simulation software. Events of confused contacts of high-voltage transmission lines with overhead ground wires have the following common conditions: gust blows nearly perpendicularly to the line direction; no obstacles exist in upwind directions; the wind blows upward or downward against high-voltage transmission lines; and size of the high-voltage transmission lines is 25 mm{sup 2}. According to photographs of transmission line vibration, it appears that gust caused a high-voltage transmission line on the upwind side to jump resulting in confused contact with the overhead ground wire. The physical measurement uses such devices as an image recording device, an anemometer, a ...
1996-03-25
Energy Technology Data Exchange (ETDEWEB)
This paper reports the study results on the standard weather data necessary for simulation of PV power generation systems in fiscal 1994. In the study on the selection criterion of the standard weather data from the viewpoint of PV power generation systems, three typical years are used; a year with average solar radiation, and two years with extremely less and more solar radiation for safe simulation. The standard weather data are arranged for output calculation of PV power generation systems by selecting the most typical year based on long-term observation data. The data to be arranged are as follows; total, direct and scattered solar radiations incident upon a horizontal surface, solar radiation upon a slope surface, sunshine duration, air temperature, wind direction, wind velocity, amount of precipitation, and snow depth. For arrangement of the nationwide standard weather data, estimation of total solar radiation is necessary based on ...
1994-12-01
Renewable energy technology from underpinning physics to engineering application
International Nuclear Information System (INIS)
The UK Energy Research Centre (UKERC) in it's submission to the DTI's 2006 Energy Review reminded us that the 'UK has abundant wind, wave and tidal resources available; its mild climate lends itself to bio-energy production, and solar radiation levels are sufficient to sustain a viable solar industry'. These technologies are at different stages of development but they all draw on basic and applied Science and Engineering. The paper will briefly review the renewable energy technologies and their potential for contributing to a sustainable energy supply. Three research topics will be highlighted that bridge the gap between the physics underpinning the energy conversion, and the engineering aspects of development and deployment; all three are highly relevant to the Government's programme on micro-generation. Two are these are taken from field of thin film photovoltaics (PV), one related to novel device development and the other to a measurement technique for assessing ...
2008-03-01
Renewable energy in the urban setting: Year two
Energy Technology Data Exchange (ETDEWEB)
At the 1996 Conference in North Carolina, The Green Institute began to share its story. Their presentation this year will cover where they are in the design process and their plans for using solar and wind technologies in the development of an Eco-Industrial Park and Business Incubator. Located in a Federal Enterprise Community in Minneapolis, this project borrows sustainable and green building principles using the Rocky Mountain Institute and Solar Living Center as models. Using a change in the paradigm regarding how industry does business, The Green Institute is joining with developments across the country that are putting together Eco-Industrial Parks which use closed loop production systems to reduce waste and emissions generated from manufacturing processes. Using renewable energy, both solar and wind, presents challenges both in the integration of systems on this small site and the educational opportunities with a large potential audience ...
1997-12-31
Northeast-southwest structural transect: Rocky Mountain foreland, Wyoming
Energy Technology Data Exchange (ETDEWEB)
A northeast-southwest structural transect has been constructed across the Rocky Mountain foreland in Wyoming, a distance of about 400 mi. The line of transect begins in the northern Black Hills and traverses the northern Powder River basin, the Bighorn Mountains from Buffalo to Bonanza, the Big Horn basin from Worland to Hamilton dome, the Owl Creek Mountains, the northern Wind River basin at Maverick Springs, the Wind River Mountains to Pinedale in the Green River basin, the Moxa Arch at Big Piney and Riley Ridge, and into the thrust belt, ending at the Idaho border. In terms of a vertical and horizontal scale of 1 in. = 2000 ft, the section is about 90 ft long (i.e., the section is approximately 409 mi long). The data base for the transect includes published geologic maps, commercial photogeologic mapping, well data, and modern seismic data through critical parts of the basin areas. The data base provides an excellent found for analyzing ...
1987-08-01
Investigation of computational aeroacoustic tools for noise predictions of wind turbine aerofoils
International Nuclear Information System (INIS)
In this work trailing edge noise levels of a research aerofoil have been computed and compared to aeroacoustic measurements using two different approaches. On the other hand, aerodynamic and aeroacoustic calculations were performed with the full Navier-Stokes CFD code Fluent [Fluent Inc 2005 Fluent 6.2 Users Guide, Lebanon, NH, USA] on the basis of a steady RANS simulation. Aerodynamic characteristics were computed by the aid of various turbulence models. By the combined usage of implemented broadband noise source models, it was tried to isolate and determine the trailing edge noise level. Throughout this work two methods of different computational cost have been tested and quantitative and qualitative results obtained. On the one hand, the semi-empirical noise prediction tool NAFNoise [Moriarty P 2005 NAFNoise User's Guide. Golden, Colorado, July. http://wind.nrel.gov/designcodes/ simulators/NAFNoise] was used to directly predict trailing edge noise by taking into ...
2007-07-01
Heat transfer augmentation around a downward-facing flat plate by non-uniform electric fields
International Nuclear Information System (INIS)
The corona wind caused by nonuniform electric fields has been experimentally reported so far to be effectively applicable to heat transfer augmentation. In this paper, first, a theoretical and experimental study has been conducted to make clear such a mechanism of augmentation of heat transfer to a downward-facing flat plate due to a nonuniform electric field caused by a fine wire anode and a plate cathode as that ions produced near the wire electrode move to the plate introducing the bulk convective motion of fluid caused by collision of ions and neutral molecules. Secondly, experiments have been carried out by using twin and multi-wire electrodes and the plate to find the augmentation performance of heat transfer for the number and the arrangement of the wire electrodes, to explain the performance from the electrohydrodynamical standpoint based on the theoretical investigation and to obtain important and fundamental data to apply the corona ...
1978-08-11
Fatigue behavior of vertical axis wind turbine airfoils with two weld configurations
Energy Technology Data Exchange (ETDEWEB)
Sandia National Laboratories contracted with Rockwell International Science Center to perform a series of narrowband, pseudo-random cyclic fatigue tests on sections of 6063-T651 aluminum, Darrius-type, vertical axis wind turbine (VAWT) airfoils. We designed and constructed a load member that was mounted within the frame of a rigid 200-kip servohydraulic, closed-loop test system to hold the VAWT section and permit cantilever bending along the shear centerline of the beam. A computer program was developed to synthesize a narrow band, pseudo-random load history with fixed root mean square (RMS) stress levels at a given bandwidth and central frequency. Six specimens each of two different weld configurations at the flange mounting plate were tested at several RMS stress levels with failure defined as visual observation of a 3-inch-long crack in the VAWT. In order to test at as great a frequency as possible, a 20-kip hydraulic ram with a 10-GPM servovalve was employed ...
1989-10-01
Evaluation of advanced technologies for power transformers. Final report
Energy Technology Data Exchange (ETDEWEB)
The high insulating strength of certain gases, such as sulfur hexafluoride, when used at high pressure, suggests that there may be advantages to compressed gases as the insulating fluid in power transformers. However, simply exchanging the oil for compressed gas in an otherwise conventional transformer design will not yield a significant overall advantage. Compressed gases present the engineer with properties which are quite different from mineral oil. If gases are to be used as the major insulating fluid in power transformers, then virtually all aspects of the insulation and cooling of the apparatus must be reconsidered, affording an opportunity to introduce new design concepts, new materials, and new construction techniques. In this program, the feasibility of using the following principal design concepts has been explored: sheet conductors for the windings; a system of sealed, self-contained, annular cooling ducts containing circulating cooling fluid to cool the ...
1981-01-01
One of the most interesting discoveries of the X-ray Telescope and EUV Imaging Spectrometer (EIS) on board the Hinode solar observatory is the presence of persistent high temperature high speed outflows from the edges of active regions. Measurements by EIS indicate that the outflows reach velocities of 50 km/s with spectral line asymmetries approaching 200 km/s. It has been suggested that these outflows may lie on open field lines that connect to the heliosphere, and that they could potentially be a significant source of the slow speed solar wind. A direct link has been difficult to establish, however. In this letter, we use EIS measurements of spectral line intensities that are sensitive to changes in the relative abundance of Si and S as a result of the first ionization potential (FIP) effect, to measure the chemical composition in the outflow regions of AR 10978 over a period of 5 days in December 2007. We find that Si is always enhanced over S by a factor of ...
2010-01-01
Eddy current inspection of superconducting cable during manufacturing
Energy Technology Data Exchange (ETDEWEB)
The downstream failure of cable during winding, insulating, coil winding, and coil assembly is a significant issue in magnet production. The impact of these failures are costly both financially, and from the time to recover from this downstream failure. The current approach to cabling has been to visually inspect the cable for any gross defects during cabling. To date this has been effective in finding small defects such as crossovers for example, which drastically reduce the mechanical integrity of the strand, and thus the cable itself. But because of the large volume of cable which will be manufactured an automated flaw detection system which can inspect the cable and detect these type of defects will be needed. We have recently done an on-line experiment using an Eddy current system, and specialized Eddy current probes to inspect cable during manufacturing. We will present the results of our inspection demonstrating detection of crossovers, ...
1992-03-01
Eddy current inspection of superconducting cable during manufacturing
International Nuclear Information System (INIS)
The downstream failure of cable during winding, insulating, coil winding, and coil assembly is a significant issue in magnet production. The impact of these failures is costly both financially and because of the time needed to recover from them. The current approach to cabling has been to visually inspect the cable for any gross defects during cabling. To date this has been effective in finding small defects such as crossovers, which drastically reduce the mechanical integrity of the strand and thus of the cable itself. But because of the large volume of cable that will be manufactured, an automated flaw detection system that can inspect the cable and detect these types of defects will be needed. We have recently done an on-line experiment using an Eddy current system and specialized Eddy current probes to inspect cable during manufacturing. We will present the results of our inspection, demonstrating detection of crossovers and cold welds. ...
1992-03-04
Correlations are studied between the power density of Alfv\\'en-cyclotron waves (having frequencies between 0.02 and 2 Hz) and the ratio of the perpendicular and parallel temperature of the protons. The wave power spectrum is evaluated from high-resolution 3D magnetic field vector components, and the ion temperatures are derived from the velocity distribution functions as measured in fast solar wind during the Helios-2 primary mission at radial distances from the Sun between 0.3 AU and 0.9 AU. From our statistical analysis, we obtain a striking correlation between the increases in the proton temperature ratio and enhancements in the wave power spectrum. Near the Sun the transverse part of the wave power is often found to be by more than an order of magnitude higher than its longitudinal counterpart. Also the measured ion temperature anisotropy appears to be limited by the theoretical threshold value for the ion-cyclotron instability. This suggests that ...
2010-01-01
Energy Technology Data Exchange (ETDEWEB)
This report surveys the possibilities and restrictions of different construction materials for the purpose of the blades of a small stall regulated turbine. For example scaling up, material saving at decreasing of static or dynamic loads, comparisons of global costs based on prices per unit of weight, etc. For the mutual comparison of construction materials for turbine blades the starting point is a stall regulated horizontal axis turbine with a rotor diameter of 16 m and a tipvane speed of about 64 m/s. Short descriptions are given of the materials and of the applied production methods with the resulting blade geometry. The blade skins are dimensionized for storm loads after the optimalization of the blade geometry, needed for the design wind speed, is recorded. The resulting blade skins are mutually compared as for weight, mass inertia and bending stiffness. Also a comparison took place of the resulting reserve factors against load variations caused by gusts of ...
1988-02-01
International Nuclear Information System (INIS)
Model construction of the laboratory scale superconducting fault current limiter circuit (SFCL) has been performed. The SFCL is fault current limiter and used as electric network security. It mainly consists of a copper coil, a superconducting ring and an iron core that are concentrically arranged. The SFCL circuit is essentially a transformer where the secondary windings are being replaced by the ring of YBa_2Cu_3O_7_-_x superconductor (HTS). The ring has critical transition temperature Tc = 92 K and critical current Ic = 3.61 A. Characterization of the SFCL circuit is simulated by ANSYS version 5.4 software. The SFCL circuit consists of load and transformer impedances. The results show that the inductions of magnet field flux in the iron core of primer windings and ring disappear to one other before fault state. It means that impedance of the transformer is zero. After the condition a superconductivity behavior of the ring is disappear so ...
2004-06-01
CAR International. A simple model to determine city street air quality
Energy Technology Data Exchange (ETDEWEB)
Based on wind tunnel experiments, theoretical considerations and measurements the dispersion model CAR (Calculation of Air pollution from Road traffic) has been developed for determining air quality in city streets. CAR International is a simple parameterized model using readily available input data and calculating annual percentile values and average concentrations close to streets (at the kerb side) for non-reactive air pollutants and NO{sub 2}. Originally the model was set up for the Dutch situation (traffic, meteorology) with a system of fixed parameters. In order to extend its application to other countries the program has been made more flexible and user friendly. User defined system data can now be changed interactively, such as emission factors of passenger cars and trucks, fraction of directly emitted NO{sub 2}, city and regional background concentration, and average regional wind speed. The accuracy of the model has proved to be good ...
1995-06-22
A comparison of two operational wave assimilation methods
A comparison is carried out between two operational wave forecasting/assimilation models for the North Sea, with the emphasis on the assimilation schemes. One model is the WAM model, in combination with an optimal interpolation method (OIP). The other model, DASWAM, consists of the third generation wave model PHIDIAS in combination with an approximate implementation of the adjoint method. In an experiment over the period February 19 - March 30, 1993, the models are driven by the same wind field (HIRLAM analysis winds), and the same observation data set is assimilated. This set consists of a) spectra from three pitch-and-roll buoys and b) Synthetic Aperture Radar (SAR) spectra from the ERS-1 satellite. Three analysis/forecast runs are performed: one without assimilation, one with assimilation of buoy measurements only, and one with all data assimilated. For validation, observations from four buoys, altimeter data from ERS-1 and Topex-Poseidon, ...
1997-01-01
A MODEL OF THE SPECTRAL EVOLUTION OF PULSAR WIND NEBULAE
International Nuclear Information System (INIS)
We study the spectral evolution of pulsar wind nebulae (PWNe) taking into account the energy injected when they are young. We model the evolution of the magnetic field inside a uniformly expanding PWN. Considering time-dependent injection from the pulsar and coolings by radiative and adiabatic losses, we solve the evolution of the particle distribution function. The model is calibrated by fitting the calculated spectrum to the observations of the Crab Nebula at an age of a thousand years. The spectral evolution of the Crab Nebula in our model shows that the flux ratio of TeV #gamma#-rays to X-rays increases with time, which implies that old PWNe are faint in X-rays, but not in TeV #gamma#-rays. The increase of this ratio is because the magnetic field decreases with time and is not because the X-ray emitting particles are cooled more rapidly than the TeV #gamma#-ray emitting particles. Our spectral evolution model matches the observed rate of the radio flux decrease ...
2010-06-01
Wood-plastic composites with high toughness and dimensional stability
International Nuclear Information System (INIS)
Using acrylic-group containing isocyanates together with methyl methacrylate as impregnating mixture and gamma rays for curing wood-plastic composites have been produced, which show high-dimensional stability and toughness (low brittleness) compared to commonly used wood-plastics. The syntheses of proper acrylic-group containing isocyanates are as well described as the properties of the produced composites, made from maple wood. Also the direct use of the initial compounds, necessary for the syntheses, resulted in products of similar properties. These wood-plastic composites are to be suggested for the production of high-class products, e.g. wood-wind instruments. (author).
1982-10-01
Energy Technology Data Exchange (ETDEWEB)
This document provides information and presents data on the energy situation in many regions of Canada. The first part deals with the petroleum and the bitumen shales of Alberta (reserves, exploitation and production, environmental impacts), the second part discusses with the hydroelectricity choice of Quebec and the 2004 crisis. The nuclear situation of Ontario is presented in the third part (nuclear park, programs, uranium reserves, research and development on Candu reactors), while the fourth part deals with the renewable energies (wind power and biomass). The canadian situation facing the Kyoto protocol is discussed in the last part. (A.L.B.)
2004-12-01
The green power option to gain market advantage
Energy Technology Data Exchange (ETDEWEB)
Deregulation of the electric power industry in Alberta holds the prospect of providing greater choice for customers. One such option will be `green power` which is provided by renewable energy technologies. The energy produced would be without environmental impacts such as air emissions, water pollution, flooding, thermal emissions or waste by-products. Wind power, small scale hydro power, photovoltaics and biomass technologies have been termed as `green power`. The choices that customers make will not be focused on price alone. Market forces are emerging to demand reduction in emissions which will result in a market for `green energy` products and facilitate achieving goals for a sustainable future.
1997-03-01
Pumped storage plants in a new framework - challenges and consequences
Energy Technology Data Exchange (ETDEWEB)
Originally designed exclusively for peak load covering, pumped storage plants are now faced with new challenges brought about by the deregulation of the electricity market and the substantial growth of wind power capacity. Today's pumped storage plants are started more frequently and often for shorter periods of time. The grid controlling tasks have increased the importance of the role played by this type of power plant and improved sales considerably. But the operational demands have grown substantially as well. This paper discusses the ensuing adaptation of power plant operation as well as options available to power plant operators. (orig.)
2006-07-01
Performance measurements of the Pionier-I 15 m VAWT. Prestatiemetingen aan de Pionier-I 15 m VAWT
Energy Technology Data Exchange (ETDEWEB)
Pionier-I is a vertical axis wind turbine (VAWT) of the Darrieus-type with a diameter of 15 m. In the month of September 1983 performance and efficiency were measured. Measurements were done with constant rotational speed and with constant tip speed ratio. For the calculation of the possible (theoretical) output of electric power an anemometer was present. Measurement results are conditioned to one digital signal and processed by a microcomputer (Apple II). It becomes evident that the yearly energy output of the Pionier-I is quite well comparable with that of a horizontal axis turbine with the same diameter.
1983-01-01
On the threshold of the 21st Century in the Soviet Union
International Nuclear Information System (INIS)
In the last 30 years the production of electricity in the USSR has increased 14-fold, probably attaining 1540 billion kWH in 1985. Nuclear generation will provide the bulk of future increases of consumption, using both water-cooled and uranium/graphite reactors; stations of up to 1.5 million kW are in service. The USSR is also in the fore-front of attempts to exploit thermonuclear power. The USSR is also conducting experiments with renewable sources of energy such as solar, geothermal, wind and wave power and with magnetohydrodynamic generation. (D.A.J.).
Meterological Information System of the Karlsruhe Nuclear Research Center
Energy Technology Data Exchange (ETDEWEB)
The Meteorological Information System (MIS) comprising the meteorological instruments, the computers, and the software for data processing and recording, is part of the KfK safety and control system. In 1982 is was equipped with an independent data processing system. The report explains the arrangement and the operation of the sensors and thw two process computers. For selected meteorological situations the ability of the system is demonstrated, i.e., the presentation of the vertical profiles of wind, temperature and turbulence in the lower atmospheric boundary layer as well as the calculation and graphical representation of the transport and dispersion into the KfK environment of radioactive pollutants being released by the nuclear installations of the KfK into the atmosphere.
1984-01-01
Energy Technology Data Exchange (ETDEWEB)
This paper presents a survey on public preferences in SE England for the use of wind, biomass and nuclear power in electricity generation. Using a labelled CE the perceived importance (value) to the public of distance and the energy options' impacts on biodiversity, emissions, land occupation and household cost was explored. Results suggest that impacts, technology name, demographic characteristics, attitudes towards the environment, knowledge and experience with the technologies were significant choice determinants. Considering the current debate about the development of nuclear power and biomass in UK and worldwide, this survey provides an insight into the factors affecting public acceptability
2008-07-01
Initial results from 50mm short SSC dipoles at Fermilab
Energy Technology Data Exchange (ETDEWEB)
Several short model SSC 50 mm bore dipoles are being built and tested at Fermilab. Mechanical design of these magnets has been determined from experience involved in the construction and testing of 40 mm dipoles. Construction experience includes coil winding, curing and measuring, coil end part design and fabrication, ground insulation, instrumentation, collaring and yoke assembly. Fabrication techniques are explained and construction problems are discussed. Similarities and differences from the 40 mm dipole tooling and management components are outlined. Test results from the first models are presented. 19 refs., 12 figs.
1991-03-01
Improved beam confinement in the modified betatron with strong focusing
International Nuclear Information System (INIS)
The lifetime of the circulating electron beam in the Naval Research Laboratory modified betatron has been increased by more than 2 orders of magnitude with the addition of strong focusing windings to the device. The injected beam consistently spirals from the injector to the minor axis and is trapped. The #approx#0.5-kA trapped electron ring has been accelerated above 10 MeV from the injection energy of 0.5 to 0.6 MeV. The beam acceleration has been confirmed not only by the x-ray attenuation technique but also with the detection of photoneutrons.
International Nuclear Information System (INIS)
The components with masses 32 and 64M _s_u_n, evolved with the matter mixing in the semiconvective zone and filling their Roche lobes, after the main-sequence evolution overflow their Roche lobes and lose matter during the first part of the helium core burning. After the overflow end, the components lose the matter by stellar wind. The components shrink in the nuclear timescale. At first, they have the blue supergiant character with anomalous CNO abundance, then - the Wolf-Rayet stars character.
Energy Technology Data Exchange (ETDEWEB)
An oil-immersion electrically insulated cable of high performance is constructed by wrapping a conductor with an insulating layer formed by winding on the conductor polypropylene film, and impregnating the insulating layer with an insulating oil preferably dodecyl benzene. The polypropylene film has a density in the range of 0.905 to 0.915 g/cm/sup 3/, birefringence in the range of 0.020 to 0.035, ratio of strengths in two axial directions (tensile strength in the longitudinal direction/tensile strength in the lateral direction) in the range of 5 to 15, and thickness in the range of 70 to 300 microns.
1987-08-14
Dynamic analysis of Darrieus vertical axis wind turbine rotors
The dynamic response characteristics of the VAWT rotor are important factors governing the safety and fatigue life of VAWT systems. The principal problems are the determination of critical rotor speeds (resonances) and the assessment of forced vibration response amplitudes. The solution to these problems is complicated by centrifugal and coriolis effects which can have substantial influence on rotor resonant frequencies and mode shapes. This paper will describe and discuss the primary tools now in use at Sandia National Laboratories for rotor analysis. These tools include a lumped springmass model (VAWTDYN) and also finite-element based approaches. The discussion will center on the accuracy and completeness of current capabilities and plans for future research.
1981-01-01
Department of Energy and Climate Change : News Categories : Department of Energy and Climate Change
...Climate Change : News Categories : Department of Energy and Climate Change Articles in Smart energy meters Results There are 2 articles listed in Smart energy ... meters DECC lays foundations for smart meters rollout A crucial step in delivering the UK's energy security and low carbon future was taken today ...Nuclear Prices Renewable energy Renewable Heat Incentive Saving energy and CO2 Science Smart energy meters Statistics Statistics and projections Transparency Wave and tidal Wind ...
Automatic-control system for the 17-metre vertical-axis wind turbine (VAWT)
The 17-metre DOE/Sandia VAWT began operation in March 1977. Since that time the turbine has been operated strictly by manual control for the purpose of data acquisition and performance analysis; this procedure has limited the VAWT operation time and power output. An automatic-control system has been designed and implemented to study automatic control of a VAWT and to better judge the fatigue life and reliability of the VAWT under what will be normal operating conditions for power production. This system, including the necessary hardware, is discussed in detail along with a simplified cost analysis.
1980-03-01
Analysis of convective losses from cavity solar central receivers
Energy Technology Data Exchange (ETDEWEB)
An analytical model is presented which enables the estimation of convective losses from cavity receivers. Evidence from solar experiments is used to test the hypothesized mechanisms. The analytical results and experimental evidence indicate that the convective loss from cavity receivers is appreciable. The model indicates that the influences of the wind on the convective loss at normal operating conditions are minimal. It also shows that the internal thermal resistance, i.e. the ability to heat the air inside the cavity, are of importance. Buoyancy induced flows are, on the other hand, effective in transferring energy across the aperture. 8 refs.
1981-01-01
An analysis of convective losses from cavity solar central receivers
Energy Technology Data Exchange (ETDEWEB)
A simple analytical model has been developed in order to provide a framework for designing experimental programs for convective loss determinations, for analyzing available experimental data from solar receiver test programs, and for estimating the convective loss at a relatively small cost. Analytical results and experimental evidence indicate that the convective loss from cavity receivers is appreciable, while the effects of wind on the convective loss under normal operating conditions are minimal. The proposed analytical model provides a means of determining the relative importance of the internal resistances and predicting the bulk air temperature within the convective zone inside the cavity.
1981-01-01
A twin unidirectional impulse turbine for wave energy conversion
British Library Electronic Table of Contents (United Kingdom)
A twin unidirectional impulse turbine has been proposed in order to enhance the performance of wave energy plant. This turbine system uses two unidirectional impulse turbines and their flow direction is different from each other. However, the turbine characteristics have not been clarified to date. The performances of a unidirectional impulse turbine under steady flow conditions were investigated experimentally by using a wind tunnel with large piston/cylinder in this study. Then, efficiency of the twin impulse turbine have been estimated by a quasi-steady analysis using experimental results.
2011-01-01
DEFF Research Database (Denmark)
Retention or dispersion of larvae from the spawning grounds has been identified as one of the key processes influencing recruitment success in fish stocks. To examine the potential effects of transport on recruitment. numerical simulations were performed utilizing a three-dimensional physical oceanographic model of the Baltic Sea. Cod larvae were represented as Lagrangian drifters released in the deepwater region of the Bornholm Basin, the main spawning ground for Baltic cod. Simulations were performed for the major spawning seasons of 1993 and 1994. when annual and interannual variability of meteorological forcing was large. The principal goals of the modelling exercise were first to identify the physical processes influencing the demersal distribution of the early life stages and second to describe the transport of the pelagic stages in response to variations in windstress, thereby identifying the meteorological and hydrodynamic mechanisms influencing retention and/or dispersal. The ...
2001-01-01
Surface and subsurface analysis of Sheep Mountain anticline, Wyoming
Energy Technology Data Exchange (ETDEWEB)
The Sheep Mountain area, in the southwest Wind River Basin, is the up plunge closure of the Derby Dome-Winkleman Dome producing trend of an echelon folds which comprise the first line of folding down the northeast flank of the Wind River Mountains. The structural style exposed in the Palozoic reservoir rocks of Sheep Mountain may serve as a model for the other structural features in the Wind River Basin. As in the case of the Derby Dome and Winkleman Dome, Sheep Mountain is typically asymmetric to the southwest. Local east-directed thrusts exposed in the core of the anticline place Pennsylvania over Permian age rocks. A major change in the trend of the anticlinal crest within Sheep Mountain, suggests development of separate left-stepping en echelon closures at depth. The northwest end of Sheep Mountain also forms a left-stepping en echelon pattern with Derby Dome. The northwest plunge of Sheep Mountain is facilitated by ...
1988-01-01
Energy Technology Data Exchange (ETDEWEB)
This article presents the results of analyses of large-scale integration of wind power, photo voltaic (PV) and wave power into a Danish reference energy system. The possibility of integrating Renewable Energy Sources (RES) into the electricity supply is expressed in terms of the ability to avoid excess electricity production. The different sources are analysed in the range of an electricity production from 0 to 100% of the electricity demand. The excess production is found from detailed energy system analyses on the computer model EnergyPLAN. The analyses have taken into account that certain ancillary services are needed in order to secure the electricity supply system. The idea is to benefit from the different patterns in the fluctuations of different renewable sources. And the purpose is to identify optimal mixtures from a technical point of view. The optimal mixture seems to be when onshore wind power produces approximately 50% of the total ...
2006-04-01
Evidence for the presence of two supracrustal sequences in the central Wind River Mountain, Wyoming
Energy Technology Data Exchange (ETDEWEB)
Supracrustal rocks, although volumetrically minor, are found throughout the Archean basement of the central and northern Wind River Mountains. Detailed mapping in the Medina Mountain area suggests that at least two discrete sedimentation events are preserved. The older sequence occurs as melanosomes in a multiple deformed migmatitic gneiss. Rock types include mafic rocks (metavolcanics.), calc-silicates, iron formation and rare pelites. Although retrogression is widespread, small patches with granulite mineralogies are found preserved. The younger supracrustal sequence consists of banded amphibolites, calc-silicates, semipelitic and pelitic gneiss. These rocks form synformal structures that are up to 4 km in length. The coherent nature of these rocks and the lack of the aforementioned porphyritic dikes strongly suggests that this sequence, the Medina Mountain. Supracrustals (MMS) is considerably younger than the supracrustal rocks found in the migmatites. The ...
1985-01-01
Energy Technology Data Exchange (ETDEWEB)
An intensified integration of renewable energies and a more extensive use of combined heat and power lead to an increasingly decentralized power economy. Such an economy is characterized by the conversion of energy at the point of the energy demand and depending on the energy system, by the possibility of balancing the fluctuating supply of renewable energies. In the long run, there is no doubt that fuel cells will be part of such a sustainable and flexible energy concept. The scope of this dissertation includes an analysis of the flexibility of fuel cells in energy supply (1,5 kW{sub el}), an assessment of the potential to compensate for the fluctuating supply of wind energy by an aggregation of decentralized fuel cells and a participation as a contractor in the spot and balance energy markets. Therefore two fuel cells were monitored and tested in order to obtain their characteristics and distributions for the energy demand of households in the federal states, in ...
2010-07-01
Natural laminar-flow (NLF) airfoils are those which can achieve significant extents of laminar flow (greater than or equal to 30% chord) solely through favorable pressure gradients. Studies have shown that vertical-axis wind turbines (VAWTs) using NLF sections as blade elements have the potential of producing energy at a significantly lower cost (approx. =20%) than turbines of current design. Sandia National Laboratories (SNL) is now in the process of procuring a blade set for its 17-m-diameter research turbine which will use NLF sections as blade elements. This paper describes the design of this blade set. The blade set design began with the definition of a family of three approximately 50% chord NLF sections (15, 18, and 21% t/c). These definitions involved numerically establishing airfoil contours giving section characteristics anticipated to be favorable in the VAWT context and then screening these using a VAWT performance model. Field tests of the 15 and 18% ...
1983-01-01
International Nuclear Information System (INIS)
There is an increasing interest in using novel methods to generate electrical energy using wind and solar energy sources. Unfortunately, such energy sources are intermittent, and, therefore, conventional sources must still be available to meet demand during critical periods. In addition, renewable energy technologies are still expensive in general, although extensive research programs are being conducted to overcome this disadvantage. Hence, reliability, economic assessment and environmental impacts are three objectives to be satisfied simultaneously when designing either an autonomous or a grid-connected hybrid power generation system. The installation of any of these two systems should, undoubtedly, be preceded by an assessment of the available resources at the candidate site. In addition, many other factors are to be studied, including economics of transmission lines, site constraints, distances etc. In this thesis, the subjective judgments of various experts, ...
The impact of solar flares and magnetic storms on humans
International Nuclear Information System (INIS)
Three classes of solar emanations, namely, photon radiation from solar flares, solar energetic particles, and inhomogeneities in the solar wind that drive magnetic storms, are examined, and their effects on humans and technological systems are discussed. Solar flares may disrupt radio communications in the HF and VLF ranges. Energetic particles pose a special hazard at low-earth orbit and above, where they can penetrate barriers such as spacesuits and aluminum and destroy cells and solid state electronics. Energetic solar particles also influence terrestrial radio waves propagating through polar regions. Magnetic storms may disturb the operation of navigation instruments, power lines and pipelines, and satellites; they give rise to ionospheric storms which affect radio communication at all latitudes. There is also a growing body of evidence that changes in the geomagnetic field affect biological systems. 3 refs.
Revegetation/rock cover for stabilization of inactive U-tailings sites
International Nuclear Information System (INIS)
Soil placed over any sealant/barrier system can provide a protective mantle if the soil is not lost by erosion. Vegetation is an attractive choice for controlling erosion because it can provide an economic self-renewing cover that serves to reduce erosion by both wind and water. Vegetation alone, however, may not adequately stabilize the surface in extremely arid areas. In those areas, a properly designed surface treatment of rock cover, perhaps in conjunction with vegetation, may be necessary to stabilize the tailings surfaces. The objective of this program is to establish guidelines for surface stabilization that are compatible with sealant/barrier systems and that are suited to soils and climates at inactive uranium mill tailings sites. These guidelines will provide the means to estimate potential vegetation cover, potential erosion, effects of surface treatments on sealant/barrier systems, and costs of vegetation and rock covers. Methods for establishing ...
1982-02-01
Removal of NO and SO2 in Corona Discharge Plasma Reactor with Water Film
In this paper, a novel type of a corona discharge plasma reactor was designed, which consists of needle-plate-combined electrodes, in which a series of needle electrodes are placed in a glass container filled with flue gas, and a plate electrode is immersed in the water. Based on this model, the removal of NO and SO2 was tested experimentally. In addition, the effect of streamer polarity on the reduction of SO2 and NO was investigated in detail. The experimental results show that the corona wind formed between the high-voltage needle electrode and the water by corona discharge enhances the cleaning efficiency of the flue gas because of the presence of water, and the cleaning efficiency will increase with the increase of applied dc voltage within a definite range. The removal efficiency of SO2 up to 98%, and about 85% of NOx removal under suitable conditions is obtained in our experiments.
2004-04-01
Remote sensing analysis of rainstorm effects on sediment concentrations in Apalachicola Bay, USA
British Library Electronic Table of Contents (United Kingdom)
Remote sensing of total suspended solids (TSS) by satellite techniques in estuaries and bays plays an important role in monitoring water quality over a large area. It is valuable to the management of coastal water environment and ecosystems. In this study, remote sensing mapping of TSS was conducted to investigate the effects of rainstorm events on Apalachicola Bay. A rainstorm event (October 7-8, 2008) was selected for a period when wind speeds were weak and the river inflow was almost steady. TSS mapping of MODIS images before and after the rainstorm event showed substantial increase of TSS induced by the rainstorm. Using an image during low river discharge before the rainstorm as a reference, TSS distribution was mapped by an improved regression model using MODIS image after a rainstorm...
2011-01-01
Energy Technology Data Exchange (ETDEWEB)
The impact of the azimuthal wave refraction in the middle atmosphere on the distribution of gravity wave amplitudes, propagation azimuths, and other wave parameters is investigated using a numerical ray-tracing model of gravity wave propagation through a representative zonal mean reference model of geostrophic winds and temperature in the middle atmosphere. Simulations are first performed with only a single type of gravity wave to help explain some important effects which occur during the refraction process. Then, a multiray simulation is performed which traces a crude spectrum of waves from different altitudes through the atmosphere for every month of a climatological year. The simulated wave climatologies are compared with observations. 108 refs.
1992-10-01
Performance of air-augmented waterjet thrusters
This report describes an investigation of the performance of air-augmented waterjet thrusters. The investigation is divided into two parts. Part one describes a study of the injection of large diameter air bubbles to reduce heat transfer between the air and water and, thus, increase the thrust. This study is done analytically by solving the appropriate, governing equations. The results indicate that the approach is very worth-while since thrust can be increased ten percent as compared to air-augmentation with small bubbles. Several practical systems are discussed for injecting large air bubbles. Part two is an experimental investigation of the thrust produced under a wind range of conditions. The results show that a thrust increase of more than 20 percent can be achieved by air-augmentation. Further, the performance improves for larger thrust nozzles.
1976-11-01
Low frequency noise from MW wind turbines -- mechanisms of generation and its modeling
Energy Technology Data Exchange (ETDEWEB)
During the present project the mechanisms of generation of low frequency noise (LFN) for upwind rotors has been investigated. A 3.6 MW turbine has been simulated with a noise prediction model from NASA in US. Running the model on this turbine a number of important turbine design parameters with influence on the LFN have been identified as well as other parameters not linked to the turbine design. Of important parameters can be mentioned 1) rotor rotational speed, 2) blade/tower clearance, 3) rotor configuration - upwind/downwind, 4) unsteadiness/turbulence in inflow. Further, the directivity characteristics of LFN has been computed as well as reduction in noise as function of distance from the turbine. In general low levels of LFN has been computed for the upwind rotor in standard configuration. (au)
2008-04-15
Environmental hazards for pipelines in coastal regions/shore approaches
Energy Technology Data Exchange (ETDEWEB)
Often oil/gas and other hydrocarbons discovered and produced offshore are transported to onshore facilities via submarine pipelines. The route of such pipelines traverses through coastal/shore approach regions. For a rational/economic design, safe installation and subsequent operation it is of utmost importance to review, evaluate and finalize various environmental hazard such as winds, waves, currents, seabed topography, seabed and sub-bottom soils, seabed erosion and soil accretion. This paper addresses the above described environmental hazards, their assessment and techniques to prepare design parameters which must be used for stability analysis, installation methods, long term operation and maintenance for the shore approaches. Additionally, various proven pipeline installation and stabilization techniques for the shore approach region are detailed. As case histories, three approaches installed in the Dutch North Sea are described.
1995-12-31
Downscaling of GCM forecasts to streamflow over Scandinavia
DEFF Research Database (Denmark)
A seasonal forecasting technique to produce probabilistic and deterministic streamflow forecasts for 23 basins in Norway and northern Sweden is developed in this work. Large scale circulation and moisture fields, forecasted by the ECHAM4.5 model 4 months in advance, are used to forecast spring flows. The technique includes model output statistics (MOS) based on a non-linear Neural Network (NN) approach. Results show that streamflow forecasts from Global Circulation Model (GCM) predictions, for the Scandinavia region are viable and highest skill values were found for basins located in south-western Norway. The physical interpretation of the forecasting skill is that stations close to the Norwegian coast are directly exposed to prevailing winds from the Atlantic ocean, which constitute the principal source of predictive information from the atmosphere on the seasonal timescale.
2008-01-01
An investigation of tidal stream rotor performance
Environmental Research Database
ObjectivesThe practical exploitation of tidal stream energy is limited by man's activities in coastal waters: navigation, fishing and~%~leisure pursuits. It is important therefore to make the best use of the sites, which are available. The main objective of the~%~Proposed study is to assess the limits imposed by waves on the performance of tidal stream rotors, and to investigate way:~%~in which these limits might be related by refinements in rotor design and the control of operating conditions. Secondary~ [continued...]DescriptionHorizontal aids wind turbines have been recognised as one of the most successful renewable energy saving devices. The use of the similar concept as a 'tidy stream rotor' in offshore environment appears to be even more compelling. However, the application of this concept will require the confirmation of various operational and environmental limitations due to complexities of offshore environment compared to those of on shore. Within the ...
2004-01-29
British Library Electronic Table of Contents (United Kingdom)
In this work, we propose a conceptual distributed control framework for electrical grid integrated with distributed renewable energy generation systems in order to enable the development of the so-called ''smart electrical grid''. First, we introduce the key elements and their interactions in the proposed control architecture and discuss the design of the distributed control systems which are able to coordinate their actions to account for optimization considerations on the system operation. Subsequently, we focus on a specific wind/solar energy generation system connected to a reverse osmosis water desalination system and the electrical grid and design two supervisory predictive controllers via model predictive control to operate the integrated system taking into account short-term and lo...
2011-01-01
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