Why Kites Fly. Teacher Background for DSO for DoDDS Japan Day with Kites.

ERIC Educational Resources Information Center

Schlenker, Richard M.

This paper discusses the physical principles behind the flying ability of both kites and airplanes. This background material was developed for a program in which a Japanese kite maker conducts kite making and flying classes in the Japan School District Elementary Schools of the Department of Defense Dependents Schools (DoDDS), Pacific Region. The…

The taxonomic status of the white-tailed kite

USGS Publications Warehouse

Clark, W.S.; Banks, R.C.

1992-01-01

The White-tailed Kite (Elanus leucurus) of the Americas has been merged with the Black-shouldered (or Black-winged) Kite (E. caeruleus) of the Old World and the Australian Black-shouldered Kite (E. axillaris) by North American authorities (but not elsewhere), primarily because of similarity in plumage. However, American kites differ from Old World kites in greater size and weight, in proportions (relatively longer tail and smaller bill and feet), plumage pattern (particularly of juveniles), and in behavior. Here we argue that these characters are sufficiently distinctive to warrant recognition of E. leucurus at the species level.

An artificial perch to help Snail Kites handle an exotic Apple Snail

USGS Publications Warehouse

Pias, Kyle E.; Welch, Zach C.; Kitchens, Wiley M.

2012-01-01

In the United States, the Snail Kite (Rostrhamus sociabilis plumbeus) is a federally endangered species and restricted to the wetlands of south-central Florida where the current population numbers less than 1,500. The Snail Kite is an extreme dietary specialist, previously feeding almost exclusively on one species of snail, the Florida Apple Snail (Pomacea paludosa). Within the past decade, an exotic species of apple snail, the Island Apple Snail (Pomacea insularum), has become established on lakes in central Florida. Island Apple Snails are larger than the native Florida Apple Snails, and Snail Kites handle the exotic snails less efficiently. Juvenile Snail Kites, in particular, have lower daily energy balances while feeding on Island Apple Snails. An inexpensive, easy-to-construct platform was developed that would provide Snail Kites with a flat, stable surface on which to extract snails. The platform has the potential to reduce the difficulties Snail Kites experience when handling exotic snails, and may benefit the Snail Kite population as a whole. Initial observations indicate that Snail Kites use the platforms frequently, and snails extracted at the platforms are larger than snails extracted at other perches.

Offal dumping sites influence the relative abundance and roosting site selection of Black Kites (Milvus migrans govinda) in urban landscape: a study from Kolkata metropolis, India.

PubMed

Mazumdar, Subhendu; Ghose, Dipankar; Saha, Goutam Kumar

2017-12-14

Although Black Kites (Milvus migrans govinda) serve as major scavenging raptor in most of the urban areas, scientific studies on this important ecosystem service provider are almost non-existent in Indian context. The present study was carried out in a metropolis in eastern India to find out the factors influencing relative abundance and roosting site selection of Black Kites. Separate generalized linear models (GLMs) were performed considering encounter rate and roosting Black Kite abundance as response variables. The study conclusively indicated that encounter rates of Black Kites were significantly influenced by the presence of garbage dumps in its vicinity. Numbers of Black Kites were also higher in the roosting sites situated closer to garbage dumps and open spaces. In addition, expected counts of Black Kites significantly increased in roosting sites situated away from buildings and water bodies. However, built-up area and tree cover around the roosting sites had no influence on the abundance of Black Kites therein. With rapid urbanization and changing offal disposal patterns, our findings would be useful to ensure continued availability of food and roosting sites of Black Kites in urban areas.

Teaching ESL Content through Kite Making for Grades K-12.

ERIC Educational Resources Information Center

Alexander, N.

Ideas for teaching elementary and secondary students of English as a Second Language (ESL) through a unit on kites and kite-making are offered. First, unit objectives are outlined. These include objectives for cognitive skill development (classification, comparison), psychomotor skills (constructing a kite), mathematical operations (measuring,…

Effects of an exotic prey species on a native specialist: example of the snail kite

USGS Publications Warehouse

Cattau, Christopher E.; Martin, J.; Kitchens, Wiley M.

2010-01-01

Despite acknowledging that exotic species can exhibit tremendous influence over native populations, few case studies have clearly demonstrated the effects of exotic prey species on native predators. We examined the effects of the recently introduced island apple snail (Pomacea insularum) on the foraging behavior and energetics of the endangered snail kite (Rostrhamus sociabilis plumbeus) in Florida. We conducted time-activity budgets: (i) on kites foraging for native Florida apple snails (Pomacea paludosa) in major wetland units within the kites' range that had not been invaded by the exotic island apple snail and (ii) on kites foraging for exotic apple snails in Lake Tohopekaliga, the only major wetland utilized by the snail kite that had suffered a serious invasion of P. insularum. When foraging for P. insularum, snail kites dropped a greater proportion of snails, and they experienced increased handling times and decreased consumption rates; however, kites foraging for P. insularum also spent a smaller proportion of the day in flight. Estimates of net daily energy balances between kites feeding on P. insularum versus P. paludosa were comparable for adults, but juveniles experienced energetic deficiencies when feeding on the exotic snail. Due to this discrepancy, we hypothesize that wetlands invaded by P. insularum, such as Lake Tohopekaliga, may function as ecological traps for the snail kite in Florida by attracting breeding adults but simultaneously depressing juvenile survival. This study highlights the conservation implications and importance of elucidating the effects that exotic species have on native specialists, especially those that are endangered, because subtle influences on behavior may have significant population consequences.

Effects of an exotic prey species on a native specialist: Eexample of the snail kite

USGS Publications Warehouse

Cattau, Christopher E.; Martin, J.; Kitchens, W.M.

2010-01-01

Despite acknowledging that exotic species can exhibit tremendous influence over native populations, few case studies have clearly demonstrated the effects of exotic prey species on native predators. We examined the effects of the recently introduced island apple snail (Pomacea insularum) on the foraging behavior and energetics of the endangered snail kite (Rostrhamus sociabilis plumbeus) in Florida. We conducted time-activity budgets: (i) on kites foraging for native Florida apple snails (Pomacea paludosa) in major wetland units within the kites' range that had not been invaded by the exotic island apple snail and (ii) on kites foraging for exotic apple snails in Lake Tohopekaliga, the only major wetland utilized by the snail kite that had suffered a serious invasion of P. insularum. When foraging for P. insularum, snail kites dropped a greater proportion of snails, and they experienced increased handling times and decreased consumption rates; however, kites foraging for P. insularum also spent a smaller proportion of the day in flight. Estimates of net daily energy balances between kites feeding on P. insularum versus P. paludosa were comparable for adults, but juveniles experienced energetic deficiencies when feeding on the exotic snail. Due to this discrepancy, we hypothesize that wetlands invaded by P. insularum, such as Lake Tohopekaliga, may function as ecological traps for the snail kite in Florida by attracting breeding adults but simultaneously depressing juvenile survival. This study highlights the conservation implications and importance of elucidating the effects that exotic species have on native specialists, especially those that are endangered, because subtle influences on behavior may have significant population consequences. ?? 2009 Elsevier Ltd.

Let's Go Fly a Kite!

ERIC Educational Resources Information Center

Leonard, Jacqueline

2002-01-01

Introduces a weekend science program for early childhood and elementary school students. Uses kites to teach about lightening as a source of electricity and aerodynamics. Includes directions on how to make a kite. (YDS)

Exploring the effect of drought extent and interval on the Florida snail kite: Interplay between spatial and temporal scales

USGS Publications Warehouse

Mooij, Wolf M.; Bennetts, Robert E.; Kitchens, Wiley M.; DeAngelis, Donald L.

2002-01-01

The paper aims at exploring the viability of the Florida snail kite population under various drought regimes in its wetland habitat. The population dynamics of snail kites are strongly linked with the hydrology of the system due to the dependence of this bird species on one exclusive prey species, the apple snail, which is negatively affected by a drying out of habitat. Based on empirical evidence, it has been hypothesised that the viability of the snail kite population critically depends not only on the time interval between droughts, but also on the spatial extent of these droughts. A system wide drought is likely to result in reduced reproduction and increased mortality, whereas the birds can respond to local droughts by moving to sites where conditions are still favourable. This paper explores the implications of this hypothesis by means of a spatially-explicit individual-based model. The specific aim of the model is to study in a factorial design the dynamics of the kite population in relation to two scale parameters, the temporal interval between droughts and the spatial correlation between droughts. In the model high drought frequencies led to reduced numbers of kites. Also, habitat degradation due to prolonged periods of inundation led to lower predicted numbers of kites. Another main result was that when the spatial correlation between droughts was low, the model showed little variability in the predicted numbers of kites. But when droughts occurred mostly on a system wide level, environmental stochasticity strongly increased the stochasticity in kite numbers and in the worst case the viability of the kite population was seriously threatened.

From Kites through Cold War: The Evolution of United States Air Force Manned Airborne ISR

DTIC Science & Technology

2016-06-06

Spies: The Story of America’s First Spy Ring (New York, NY: Bantam Books, 2006). 4 Stephen W. Sears, Gettysburg (Boston, MA: Houghton Mifflin, 2003...When the war slipped into trench-based stalemate, manned airborne ISR became the unblinking eye that prevented freedom of movement for either side...of dried bamboo attached to them. When the wind blew through the bamboo, a sound similar to moans and screeches was created. According to the story

Fatal Wounds by "Manja" to a Motorbike Rider in Motion.

PubMed

Borkar, Jaydeo Laxman; Tumram, Nilesh Keshav; Ambade, Vipul Namdeorao; Dixit, Pradeep Gangadhar

2015-07-01

"Kite fights" are quite popular throughout Asia. Most kite variations, including the fighter kites of India, Pakistan, and Japan, are small, flat, roughly diamond-shaped kites composed of paper, with a tapered bamboo spine and a balanced bow. They are flown with the help of a "Manja," which is a thread made of cotton or nylon, and coated with fine glass powder using glue and other chemical adhesives to cut down opponent's kite string. The nylon "Manja" is particularly more dangerous, as it not only cuts down opponent's kite string but also causes bodily injuries to humans, which may be at times fatal. The pattern of injuries by Manja is underreported in literature. In the present case, the deceased had encountered fatal injuries by "Manja" while riding on his motorbike. This case discusses the pattern of injuries caused by Manja when the victims are in motion on their two-wheelers. © 2015 American Academy of Forensic Sciences.

Up, Up and Away.

ERIC Educational Resources Information Center

Markle, Sandra

1988-01-01

Kite flying as a fun class project is proposed as a way of letting students apply what they've learned about air. A design for a kite made from a trash bag is provided, as are kite flying tips and resources. (MT)

Exploring the temporal effects of seasonal water availability on the snail kite of Florida: Part III

USGS Publications Warehouse

Mooij, Wolf M.; Martin, Julien; Kitchens, Wiley M.; DeAngelis, Donald L.

2007-01-01

The Florida snail kite (Rostrhamus sociabilis) is an endangered raptor that occurs as an isolated population, currently of about 2,000 birds, in the wetlands of southern and central Florida, USA. Its exclusive prey species, the apple snail (Pomacea paludosa) is strongly influenced by seasonal changes in water abundance. Droughts during the snail kite breeding season have a direct negative effect on snail kite survival and reproduction, but droughts are also needed to maintain aquatic vegetation types favorable to snail kite foraging for snails. We used a spatially explicit matrix model to explore the effects of temporal variation in water levels on the viability of the snail kite population under different temporal drought regimes in its wetland breeding habitat. We focused on three aspects of variations in water levels that were likely to affect kites: (1) drought frequency; (2) drought duration; and (3) drought timing within the year. We modeled a 31-year historical scenario using four different scenarios in which the average water level was maintained constant, but the amplitude of water level fluctuations was modified. Our results reveal the complexity of the effects of temporal variation in water levels on snail kite population dynamics. Management implications of these results are discussed. In particular, management decisions should not be based on annual mean water levels alone, but must consider the intra-annual variability.

Everglade kites feed on nonsnail prey

USGS Publications Warehouse

Sykes, P.W.; Kale, H.W.

1974-01-01

The Everglade Kite (Rostrhamus sociabilis plumbeus) of Florida has been called snail hawk or snail kite because it was thought to feed exclusively on the soft parts of the freshwater apple snail (Pomacea paludosa) (Nicholson 1926, Howell 1932, Bent 1937, Snyder and Snyder 1969). Furthermore, the other three subspecies of this wide-ranging Neotropical raptor (Friedmann 1950) are known to feed only on species within the genus Pomacea (Haverschmidt 1962, 1970; Brown and Amadon 1968). We report here two different instances of kites feeding on nonsnail prey in Florida

KITE POWER FOR NAMIBIA, AFRICA

EPA Science Inventory

The Phase I WPI Kite Power Team consisted of eleven WPI students, Dr. David J. Olinger (PI), Dr. Jitendra of the Rohm and Haas Company, and Dale Perkins of Heifer International’s Overlook Farm. The work of the WPI Kite Power Team was completed in two student projects, a ...

14 CFR 101.7 - Hazardous operations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.7 Hazardous operations. (a) No person may operate any moored balloon, kite, amateur rocket, or... operating any moored balloon, kite, amateur rocket, or unmanned free balloon may allow an object to be...

14 CFR 101.7 - Hazardous operations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.7 Hazardous operations. (a) No person may operate any moored balloon, kite, amateur rocket, or... operating any moored balloon, kite, amateur rocket, or unmanned free balloon may allow an object to be...

14 CFR 101.7 - Hazardous operations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.7 Hazardous operations. (a) No person may operate any moored balloon, kite, amateur rocket, or... operating any moored balloon, kite, amateur rocket, or unmanned free balloon may allow an object to be...

14 CFR 101.7 - Hazardous operations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.7 Hazardous operations. (a) No person may operate any moored balloon, kite, amateur rocket, or... operating any moored balloon, kite, amateur rocket, or unmanned free balloon may allow an object to be...

14 CFR 101.7 - Hazardous operations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.7 Hazardous operations. (a) No person may operate any moored balloon, kite, amateur rocket, or... operating any moored balloon, kite, amateur rocket, or unmanned free balloon may allow an object to be...

Making a Kite: The "Very" First Flying Machine

ERIC Educational Resources Information Center

Mitts, Charles

2013-01-01

The kite design activity described in this article is "hands-on" and provides students the opportunity to learn and apply STEM concepts in the process of building and flying a traditional diamond-shaped bowed kite from scratch. Important components of the activity are that students read and follow instructions and lessons about the…

Go Fly a Kite

ERIC Educational Resources Information Center

Klopack, Ken

2009-01-01

This article describes an "art kite" activity. The idea is to construct and decorate a non-flying kite that they could display for an art exhibit. Through the activity, students learn to give and take suggestions from one another, improve the quality of their work and set a wonderful atmosphere of collaboration. (Contains 1 online resource.)

Flights of Imagination. An Introduction to Aerodynamics.

ERIC Educational Resources Information Center

Hosking, Wayne

The study and use of kites have contributed to science through the development of aeronautics. This document traces some of the history of kites and provides teachers and students with basic information about kite components and flight dynamics. The major portion of the book provides students with 18 projects which deal with: (1) shapes that will…

Swallow-tailed kite nesting in Texas: Past and present

Treesearch

Raymond E. Brown; J. Howard Williamson; Dan B. Boone

1997-01-01

The historical breeding range of the swallow-tailed kite (Elanoides forficatus) in the United States extended from the Carolinas and Tennessee south through Florida, and Wisconsin and Minnesota south through louisiana, and Nebraska to central and southeastern Texas (Cely, 1979; Johnsgard,. 1990). By 1900, the range of the swallow-tailed kite was...

mapKITE: a New Paradigm for Simultaneous Aerial and Terrestrial Geodata Acquisition and Mapping

NASA Astrophysics Data System (ADS)

Molina, P.; Blázquez, M.; Sastre, J.; Colomina, I.

2016-06-01

We introduce a new mobile, simultaneous terrestrial and aerial, geodata collection and post-processing method: mapKITE. By combining two mapping technologies such as terrestrial mobile mapping and unmanned aircraft aerial mapping, geodata are simultaneously acquired from air and ground. More in detail, a mapKITE geodata acquisition system consists on an unmanned aircraft and a terrestrial vehicle, which hosts the ground control station. By means of a real-time navigation system on the terrestrial vehicle, real-time waypoints are sent to the aircraft from the ground. By doing so, the aircraft is linked to the terrestrial vehicle through a "virtual tether," acting as a "mapping kite." In the article, we entail the concept of mapKITE as well as the various technologies and techniques involved, from aircraft guidance and navigation based on IMU and GNSS, optical cameras for mapping and tracking, sensor orientation and calibration, etc. Moreover, we report of a new measurement introduced in mapKITE, that is, point-and-scale photogrammetric measurements [of image coordinates and scale] for optical targets of known size installed on the ground vehicle roof. By means of accurate posteriori trajectory determination of the terrestrial vehicle, mapKITE benefits then from kinematic ground control points which are photogrametrically observed by point-and-scale measures. Initial results for simulated configurations show that these measurements added to the usual Integrated Sensor Orientation ones reduce or even eliminate the need of conventional ground control points -therefore, lowering mission costs- and enable selfcalibration of the unmanned aircraft interior orientation parameters in corridor configurations, in contrast to the situation of traditional corridor configurations. Finally, we report about current developments of the first mapKITE prototype, developed under the European Union Research and Innovation programme Horizon 2020. The first mapKITE mission will be held at the BCN Drone Center (Collsuspina, Moià, Spain) in mid 2016.

Nesting biology of Black-shouldered Kite (Elanus caeruleus) in oil palm landscape in Carey Island, Peninsular Malaysia.

PubMed

Ramli, Rosli; Fauzi, Aimi

2018-03-01

Black-shouldered Kite ( Elanus caeruleus ) is a well-known raptor that inhabits open areas such as oil palm plantation or paddy field. To determine preferable habitat and nesting site of Black-shouldered Kite in oil palm landscape, we conducted a study on Black-shouldered Kite's nesting biology in Carey Island, Selangor, Malaysia. We divided the island into six types of habitat and conducted road-side count of Black-shouldered Kite from April 2009 to February 2011. Whenever the Black-shouldered Kite was detected, we thoroughly searched the surrounding area for their nest. In total, we have recorded forty nests. The nests were built on 15 species of trees but most of the trees shared common physical characteristics. Some novice breeders also used oil palm tree as their nesting site. Structure and building materials of nests constructed on oil palm trees were different from nests built on other trees. Of all breeding attempts, only four nests which were located in residential area adjacent to young oil palm habitat were successful. Among important characteristics of successful nesting site include taller trees with strong branches and good leaf coverage. These trees not only protect nests from predator detection (except from other predatory birds) and physical environment but also facilitate Black-shouldered Kite's foraging activities by providing good vantage point.

Ever Fly a Tetrahedron?

ERIC Educational Resources Information Center

King, Kenneth

2004-01-01

Few things capture the spirit of spring like flying a kite. Watching a kite dance and sail across a cloud spotted sky is not only a visually appealing experience it also provides a foundation for studies in science and mathematics. Put simply, a kite is an airfoil surface that flies when the forces of lift and thrust are greater than the forces of…

Widespread supplementary feeding in domestic gardens explains the return of reintroduced Red Kites Milvus milvus to an urban area.

PubMed

Orros, Melanie E; Fellowes, Mark D E

2015-04-01

Reintroductions are commonly used to mitigate biodiversity loss. One prominent example is that of the Red Kite Milvus milvus , a charismatic raptor of conservation concern. This species has been reintroduced across the UK over the last 25 years following its near extinction after centuries of persecution. The species was not expected to recolonize urban areas; its historical association with human settlements is attributed to scavenging on human waste and refuse, a resource now greatly reduced on the streets of modern European cities. However, the species has become a common daytime visitor to a large conurbation centred on the town of Reading, southern England, approximately 20 km from the first English reintroduction site. Given a near-absence of breeding and roost sites, we investigated foraging opportunities and habitat associations that might explain use by Red Kites of this urban area. Surveys of discarded human foods and road-kill suggested that these could support at most 13-29 Kites per day. Face-to-face surveys of a cross-section of residents revealed that 4.5% (equivalent to 4349 households) provided supplementary food for Red Kites in their gardens. Using estimates of per-household resource provision from another study, we calculated that this is potentially sufficient to feed 142-320 Kites, a substantial proportion of the total estimated to visit the conurbation each day (between 140 and 440). Road transects found positive associations between Red Kites and residential areas. We suggest that the decision made by thousands of householders to provide supplementary food for Red Kites in their gardens is the primary factor explaining their daytime abundance in this urban area.

Playthings as Art Objects: Ideas and Resources. Kites and Sound Making Objects and Playing Cards and Dolls.

ERIC Educational Resources Information Center

City of Birmingham Polytechnic (England). Dept. of Art.

Five booklets focusing on playthings as art objects draw together information about historical, ethnographic, and play traditions of various cultures of the world. The first booklet provides an overview of ideas and resources about kites, sound making objects, playing cards, and dolls. The second booklet on kites discusses the distribution and…

Analysis of the NASA/MSFC airborne Doppler lidar results from San Gorgonio Pass, California

NASA Technical Reports Server (NTRS)

Cliff, W. C.; Skarda, J. R.; Renne, D. S.; Sandusky, W. F.

1985-01-01

The NASA/MSFC Airborne Doppler Lidar System was flown in July 1981 aboard the NASA/Ames Convair 990 on the east side of San Gorgonio Pass California, near Palm Springs, to measure and investigate the accelerated atmospheric wind field discharging from the pass. At this region, the maritime layer from the west coast accelerates through the pass and spreads out over the valley floor on the east side of the pass. The experiment was selected in order to study accelerated flow in and at the exit of the canyon. Ground truth wind data taken concurrently with the flight data were available from approximately 12 meteorological towers and 3 tala kites for limited comparison purposes. The experiment provided the first spatial data for ensemble averaging of spatial correlations to compute lateral and longitudinal length scales in the lateral and longitudinal directions for both components, and information on atmospheric flow in this region of interest from wind energy resource considerations.

Prey use and provisioning rates of urban-nesting Mississippi Kites in west Texas

USGS Publications Warehouse

Welch, Brandi C.; Boal, Clint W.

2015-01-01

Urban ecosystems are attractive to several raptor species, including the Mississippi Kite (Ictinia mississippiensis). To better understand the niche filled by urban-nesting Mississippi Kites, we observed nesting kites at 10 nests for a total of 269 hr during the breeding seasons of 2010 and 2011. We assessed prey delivery rates and prey use within and between years, evaluated the influences of nestling age, time of day, day of year, and local atmospheric conditions on delivery rates, and examined provisioning rates by male and female kites. A 62% decrease in the prey delivery rate, measured by the number of prey deliveries, from 2010 to 2011 was likely attributable to extreme heat and drought during the 2011 breeding season. However, total biomass of identified deliveries increased 38.9% in 2011 due to an increase in the percentage of avian prey (from 1% to 16% of identified deliveries). We suspect that differences in weather conditions between years influenced the type of prey delivered, and our modeling efforts indicated that year, nestling age, time of day, and temperature best explained the number of prey deliveries made per hour. On average, females delivered more prey items than males, but variability among nests suggested additional factors may influence parental effort. Our results suggest that Mississippi Kites exhibit prey switching under differing conditions.

Experimental Test of Preferences for an Invasive Prey by an Endangered Predator: Implications for Conservation.

PubMed

Wilcox, Rebecca C; Fletcher, Robert J

2016-01-01

Identifying impacts of exotic species on native populations is central to ecology and conservation. Although the effects of exotic predators on native prey have received much attention, the role of exotic prey on native predators is poorly understood. Determining if native predators actively prefer invasive prey over native prey has implications for interpreting invasion impacts, identifying the presence of evolutionary traps, and predator persistence. One of the world's most invasive species, Pomacea maculata, has recently established in portions of the endangered Everglade snail kite's (Rostrhamus sociabilis plumbeus) geographic range. Although these exotic snails could provide additional prey resources, they are typically much larger than the native snail, which can lead to lower foraging success and the potential for diminished energetic benefits in comparison to native snails. Nonetheless, snail kites frequently forage on exotic snails. We used choice experiments to evaluate snail kite foraging preference in relation to exotic species and snail size. We found that snail kites do not show a preference for native or exotic snails. Rather, snail kites generally showed a preference for medium-sized snails, the sizes reflective of large native snails. These results suggest that while snail kites frequently forage on exotic snails in the wild, this behavior is likely driven simply by the abundance of exotic snails rather than snail kites preferring exotics. This lack of preference offers insights to hypotheses regarding effects of exotic species, guidance regarding habitat and invasive species management, and illustrates how native-exotic relationships can be misleading in the absence of experimental tests of such interactions.

Natal location influences movement and survival of a spatially structured population of snail kites

USGS Publications Warehouse

Martin, J.; Kitchens, W.M.; Hines, J.E.

2007-01-01

Despite the accepted importance of the need to better understand how natal location affects movement decisions and survival of animals, robust estimates of movement and survival in relation to the natal location are lacking. Our study focuses on movement and survival related to the natal location of snail kites in Florida and shows that kites, in addition to exhibiting a high level of site tenacity to breeding regions, also exhibit particular attraction to their natal region. More specifically, we found that estimates of movement from post-dispersal regions were greater toward natal regions than toward non-natal regions (differences were significant for three of four regions). We also found that estimates of natal philopatry were greater than estimates of philopatry to non-natal regions (differences were statistically significant for two of four regions). A previous study indicated an effect of natal region on juvenile survival; in this study, we show an effect of natal region on adult survival. Estimates of adult survival varied among kites that were hatched in different regions. Adults experienced mortality rates characteristic of the region occupied at the time when survival was measured, but because there is a greater probability that kites will return to their natal region than to any other regions, their survival was ultimately influenced by their natal region. In most years, kites hatched in southern regions had greater survival probabilities than did kites hatched in northern regions. However, during a multiregional drought, one of the northern regions served as a refuge from drought, and during this perturbation, survival was greater for birds hatched in the north. Our study shows that natal location may be important in influencing the ecological dynamics of kites but also highlights the importance of considering temporal variation in habitat conditions of spatially structured systems when attempting to evaluate the conservation value of habitats.

The Ecology and Environmental Impact of Marshland and Estuaries

DTIC Science & Technology

1992-12-15

species of water snakes, blue runners , ribbon snakes, black snakes, and bull snakes, as well as water moccassins, rattlesnakes, copperheads, and coral...be encountered there that should receive special consideration is the swallow-tailed kite . Kites in general seem to be seriously declining in parts of...the southern U.S., and a couple have a tenuous hold on their environment or, in the case of the swallow-tailed kite , have an undetermined status

Comparison of white-tailed kite food web dynamics among various habitats in California using stable isotope analysis

USGS Publications Warehouse

Iko, W.M.; Kester, C.L.; Bern, C.R.; Stendell, R.C.; Rye, R.O.

2003-01-01

The White-tailed Kite (Elanus leucurus) was once a common raptor species in the southern United States. However, by the 1930s, the species was considered on the verge of extinction until the 1940s, when a trend towards recovery was apparent. These dramatic fluctuations may be related to changes in rodent prey base due to the conversion of native wetlands to agriculture. To investigate the effects of changes in habitat, land use practices, and prey base on kite populations, we collected tissue samples from kites, their prey, and vegetation at four different locations in California: Arcata, Coastal-Coniferous Forest; Davis, mixed Urban-Agricultural; Cosumnes, Mixed Wetland-Agriculture, and Santa Barbara, Coastal-Chaparral.

The feeding habits of the snail kite in Florida, USA

USGS Publications Warehouse

Sykes, P.W.

1987-01-01

The feeding habits of the Snail Kite (Rostrhamus sociabilis) were observed intermittently from 1967-1980 in Florida, USA. Approximately 97% of all observed foraging bouts were over marshes having sparse emergent vegetation. The visually-hunting kite was unable to forage over floating mats of exotic water hyacinth (Eichhornia crassipes). Male kites had shorter hunting bouts than females. For still-hunting, the birds' perches ranged from 0.15-4.6 m high and captures occurred an average of 5.8 m from perches. Females were significantly more successful (70%) for course-hunting than males (48%), but I found no difference for still-hunting. Birds tended to forage throughout the day, except for occasional inactive periods by some individuals during midday. On cooler days, foraging commenced slightly later in the morning than on warmer days. Kites probably capture freshwater apple snails (Pomacea paludosa) as deep as 16 cm. Capture rates for adults generally ranged from 1.7-3.4 snails per hour. Kites usually foraged over a common hunting area, and defense of foraging sites was rare. Handling of snails, from the kite's arrival at the feeding perch unit consumption, averaged 2.7 min, with no significant difference between sexes. However, adult females were more efficient at the extraction portion of this process than were adult males. Snails were usually extracted before being brought to the nest, except in the latter part of the nestling period when some snails were extracted at or near the nest and some were brought intact. Adults feed small chicks bill to bill, and both parents generally shared equally in care of the young, except at two nests where the females did 67% or more of the feeding. Mean length of snails taken by kites was 42.8 mm (range 25.2-71.3 n=697) and mean diameter was 45.8 mm (range 27.4-82.4, n=697). The most common size classes tkaen were 30-60 mm in length and diameter. Nutritional and gross energy values were determined for apple snails. Female snails with albumen glands removed (versus males or mixed samples of both sexes of complete tissue or with viscera removed) had the highest caloric value (.hivin.x=4.04 kcal/g, n=10). Kites cast pellets, a behavior documented here for the first time.

Density and habitat of breeding Swallow-tailed Kites in the lower Suwannee ecosystem, Florida

USGS Publications Warehouse

Sykes, P.W.; Kepler, C.B.; Litzenberger, K.L.; Sansing, H.R.; Lewis, E.T.R.; Hatfield, J.S.

1999-01-01

Historically the Swallow-tailed Kite (Elanoides forficatus) bred in the United States in at least 16 eastern states. Currently it is restricted to seven southeastern states, with most of its breeding range in Florida. Breeding Bird Surveys indicate a declining trend for this Neotropical migrant in most of Florida. Using a rapid survey technique at the Lower Suwannee NWR on 25-27 Mar. 1997, we scanned for kites from 16 sampling stations above the forest canopy, using 10X binoculars for 45 min per station. An effective detection distance of 2.4 km provided almost complete coverage of kite habitat (excluding salt marsh) on the refuge (14,620 ha) and in a 1.6-km buffer (13,526 ha). A mobile observation platform, extended to heights of 30-34 m provided an unobstructed view above the forest canopy where foraging bouts, feeding, courtship displays, and other activities by this species occur. This technique was found to be efficient in obtaining an estimate of potential breeding pairs. An estimated 19 breeding pairs were observed, with possibly five additional pairs, a density of at least one pair per 1173-1407 ha. There was no opportunity to search for nests so we were unable to correlate number of active nests with the number of kites observed, and linear nature of study area might concentrate birds, including nonbreeders, so our density of kites may or may not be typical for other areas. The refuge has a mosaic of 11 different habitats (7 forest types, freshwater and salt marshes, open water and urban/suburban) providing much linear edge to the matrix of different plant communities that range in height from less than 1 m to greater than 30 m. Such structure provides quality habitat for Swallow-tailed Kites.

String Theory - Using Kites for Introducing Remote Sensing and In-Situ Measurement Concepts

NASA Astrophysics Data System (ADS)

Bland, G.; Bydlowski, D.; Henry, A.

2016-12-01

Kites are often overlooked as a practical and accessible tool for gaining an aerial perspective. This perspective can be used as a proxy for the vantage points of space and aircraft, particularly when introducing the concepts of remote sensing and in-situ measurements that form the foundation of much of NASA's Earth science research. Kites combined with miniature cameras and instrumentation, can easily and affordably be used in formal and informal learning environments to demonstrate techniques and develop skills related to gathering information from above. Additionally, collaborative team work can play an important role, particularly in the form of synthesizing flight operations. Hands-on technology exploration can be a component as well, as there are numerous possibilities for creating sensor systems, line-handling techniques, and understanding kite flight itself.

14 CFR 101.5 - Operations in prohibited or restricted areas.

Code of Federal Regulations, 2012 CFR

2012-01-01

... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND... a moored balloon, kite, amateur rocket, or unmanned free balloon in a prohibited or restricted area...

14 CFR 101.5 - Operations in prohibited or restricted areas.

Code of Federal Regulations, 2011 CFR

2011-01-01

... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND... a moored balloon, kite, amateur rocket, or unmanned free balloon in a prohibited or restricted area...

14 CFR 101.5 - Operations in prohibited or restricted areas.

Code of Federal Regulations, 2010 CFR

2010-01-01

... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND... a moored balloon, kite, amateur rocket, or unmanned free balloon in a prohibited or restricted area...

14 CFR 101.5 - Operations in prohibited or restricted areas.

Code of Federal Regulations, 2014 CFR

2014-01-01

... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND... a moored balloon, kite, amateur rocket, or unmanned free balloon in a prohibited or restricted area...

14 CFR 101.5 - Operations in prohibited or restricted areas.

Code of Federal Regulations, 2013 CFR

2013-01-01

... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND... a moored balloon, kite, amateur rocket, or unmanned free balloon in a prohibited or restricted area...

The effect of changes in habitat conditions on the movement of juvenile Snail Kites Rostrhamus sociabilis

USGS Publications Warehouse

Bowling, Andrea C.; Martin, Julien; Kitchens, Wiley M.

2012-01-01

The degradation of habitats due to human activities is a major topic of interest for the conservation and management of wild populations. There is growing evidence that the Florida Everglades ecosystem continues to suffer from habitat degradation. After a period of recovery in the 1990s, the Snail Kite Rostrhamus sociabilis population suffered a substantial decline in 2001 and has not recovered since. Habitat degradation has been suggested as one of the primary reasons for this lack of recovery. As a consequence of the continued degradation of the Everglades, we hypothesized that this would have led to increased movement of juvenile Kites over time, as a consequence of the need to find more favourable habitat. We used multistate mark-recapture models to compare between-site movement probabilities of juvenile Snail Kites in the 1990s (1992–95; which corresponds to the period before the decline) and 2000s (2003–06; after the decline). Our analyses were based on an extensive radiotelemetry study (266 birds tracked monthly over the entire state of Florida for a total period of 6 years) and considered factors such as sex and age of marked individuals. There was evidence of increased movement of juvenile Snail Kites during the post-decline period from most of the wetland regions used historically by Kites. Higher movement rates may contribute to an increase in the probability of mortality of young individuals and could contribute to the observed declines.

Kite: Status of the External Metrology Testbed for SIM

NASA Technical Reports Server (NTRS)

Dekens, Frank G.; Alvarez-Salazar, Oscar; Azizi, Alireza; Moser, Steven; Nemati, Bijan; Negron, John; Neville, Timothy; Ryan, Daniel

2004-01-01

Kite is a system level testbed for the External Metrology system of the Space Interferometry Mission (SIM). The External Metrology System is used to track the fiducial that are located at the centers of the interferometer's siderostats. The relative changes in their positions needs to be tracked to tens of picometers in order to correct for thermal measurements, the Kite testbed was build to test both the metrology gauges and out ability to optically model the system at these levels. The Kite testbed is an over-constraint system where 6 lengths are measured, but only 5 are needed to determine the system. The agreement in the over-constrained length needs to be on the order of 140 pm for the SIM Wide-Angle observing scenario and 8 pm for the Narrow-Angle observing scenario. We demonstrate that we have met the Wide-Angle goal with our current setup. For the Narrow-Angle case, we have only reached the goal for on-axis observations. We describe the testbed improvements that have been made since our initial results, and outline the future Kite changes that will add further effects that SIM faces in order to make the testbed more SIM like.

Balloon Measurements of Electric Fields in Thunderstorms: A Modern Version of Benjamin Franklin's Kite

NASA Astrophysics Data System (ADS)

Marshall, T. C.; Stolzenburg, M.

2006-12-01

One of Benjamin Franklin's most famous experiments was the kite experiment, which showed that thunderstorms are electrically charged. It is not as commonly noted that the kite experiment was also one of the the first attempts to make an in situ measurement of any storm parameter. Franklin realized the importance of making measurements close to and within storms, and this realization has been shared by later atomspheric scientists. In this presentation we focus on a modern version of Franklin's kite--instrumented balloons--used for in situ measurements of electric field and other storm parameters. In particular, most of our knowledge of the charge structure inside thunderstorms is based on balloon soundings of electric field. Balloon measurements of storm electricity began with the work of Simpson and colleagues in the 1930's and 1940's. The next major instrumentation advances were made by Winn and colleagues in the 1970's and 1980's. Today's instruments are digital versions of the Winn design. We review the main instrument techniques that have allowed balloons to be the worthy successors to kites. We also discuss some of the key advances in our understanding of thunderstorm electrification made with in situ balloon-borne instruments.

A new android smartphone app for geospatial mapping from drones and kites

NASA Astrophysics Data System (ADS)

Anderson, Karen; Griffiths, Dave; Debell, Leon; Steve, Hancock; James, Duffy; Jamie, Shutler; Liam, Reinhardt; Griffiths, Amber; Threadgill, Katie

2016-04-01

This paper will describe the development, testing and deployment of a free-to-use, open-source, android-based smartphone application for capturing geo-tagged aerial photographs for grass-roots remote sensing (RS) and mapping applications. Historically, RS data have been acquired from sensors on platforms such as piloted aircraft or satellites but a new self-service, and to some extent, 'grassroots' (participatory and distributed) RS revolution is underway making use of drones and kites as platforms for proximal observations of environmental phenomena. There are a growing number of papers in the geosciences and in landscape ecology utilising such platforms for cost-effective, self-service acquisition of RS data. These platforms cannot carry the heavy payloads used on satellites or aircraft, but they offer a more flexible way of gathering responsive survey data, and their low flying capability means that very fine-grained data can be captured easily. The current scientific focus for drone- and kite-based aerial mapping relies on automatically-triggered camera systems, followed by complex post-processing algorithms (e.g. computer vision-based 'structure-from-motion' software) to convert the resulting aerial photography data into orthorectified maps and point clouds. Whilst these approaches generate high quality products, for many applications the complexity is a barrier to uptake. Wiring the camera to an autopilot trigger is non-trivial, and the post-processing stage demands expensive and complex software and high performance computing. For many basic mapping applications, the workflow is too complex and the detail in the products exceed what is really needed. We asked: what if a basic smartphone, with its plethora of on-board sensors (accelerometer, GPS, compass, camera) could be used to generate ready-to-use spatial data from lightweight aerial platforms such as drones or kites? We built an android application to test the capability of standard smartphones as remote sensing devices. The application uses a visual coding 'scheme blocks' framework, so that users can customise their own data capture tools in the field. In our presentation we will demonstrate the coding framework, and then we will show the results that were gathered when we used the app to collect data during test flights - utilising various kite and lightweight drone platforms. We have also developed a simple to use open-source geospatial toolkit to allow geographical information system (GIS)-ready GeoTIFF images to be processed from the metadata stored by the app. We will demonstrate how this works in our presentation. Two Android smartphones were used in testing - a high specification OnePlus One handset and a lower cost Acer Liquid Z3 handset. We will show that the best results were obtained with the higher specification phone when it was attached to a single line kite or to a gliding drone. Finally, we will use data collected using the app, over a farmyard to demonstrate the power of the resultant fine-grained products for a simple application - advising farmers about small-scale interventions they can make to improve the quality of water run-off from their farms. The app can be downloaded freely, and used wherever an Android smartphone and aerial platform are available to deliver rapid spatial data (e.g. disaster zones, in teaching or for grassroots democratic mapping). [https://play.google.com/store/apps/details?id=foam.uavtoolkit&hl=en

A numerical 4D Collision Risk Model

NASA Astrophysics Data System (ADS)

Schmitt, Pal; Culloch, Ross; Lieber, Lilian; Kregting, Louise

2017-04-01

With the growing number of marine renewable energy (MRE) devices being installed across the world, some concern has been raised about the possibility of harming mobile, marine fauna by collision. Although physical contact between a MRE device and an organism has not been reported to date, these novel sub-sea structures pose a challenge for accurately estimating collision risks as part of environmental impact assessments. Even if the animal motion is simplified to linear translation, ignoring likely evasive behaviour, the mathematical problem of establishing an impact probability is not trivial. We present a numerical algorithm to obtain such probability distributions using transient, four-dimensional simulations of a novel marine renewable device concept, Deep Green, Minesto's power plant and hereafter referred to as the 'kite' that flies in a figure-of-eight configuration. Simulations were carried out altering several configurations including kite depth, kite speed and kite trajectory while keeping the speed of the moving object constant. Since the kite assembly is defined as two parts in the model, a tether (attached to the seabed) and the kite, collision risk of each part is reported independently. By comparing the number of collisions with the number of collision-free simulations, a probability of impact for each simulated position in the cross- section of the area is considered. Results suggest that close to the bottom, where the tether amplitude is small, the path is always blocked and the impact probability is 100% as expected. However, higher up in the water column, the collision probability is twice as high in the mid line, where the tether passes twice per period than at the extremes of its trajectory. The collision probability distribution is much more complex in the upper end of the water column, where the kite and tether can simultaneously collide with the object. Results demonstrate the viability of such models, which can also incorporate empirical field data for assessing the probability of collision risk of animals with an MRE device under varying operating conditions.

Hanging On by a Thread

NASA Technical Reports Server (NTRS)

Morgan, Ray

2004-01-01

The first solar plane we developed at AeroVironment was named the Gossamer Penguin. The word "gossamer" was an apt description of the appearance of this strange-looking aircraft that had a structural weight of only 54 pounds, with a wing span of 71 feet. Much was sacrificed to save weight and maximize span, and this presented serious problems when handling the aircraft on the ground. The Penguin was barely strong enough to stay together in the light winds and low turbulence of the early and low turbulence of the early morning. Moving the Penguin back to the hangar at the end of a morning flight was much like walking a 71-foot span kite home from the park.

Influence of an extreme high water event on survival, reproduction, and distribution of snail kites in Florida, USA

USGS Publications Warehouse

Bennetts, R.E.; Kitchens, W.M.; Dreitz, V.J.

2002-01-01

Hydrology frequently has been reported as the environmental variable having the greatest influence on Florida snail kite (Rostrhamus sociabilis) populations. Although drought has received the most attention, high-water conditions also have been reported to affect kites. Years of high water generally have been reported to be favorable for nesting, although prolonged high water may be detrimental to sustaining suitable habitat. During 1994 and 1995, southern Florida experienced an extreme high water event. This event enabled us to compare survival, nesting success, number of young per successful nest, and spatial distribution of nesting before, during, and after the event. We found no evidence of an effect (either negative or positive) on survival of adult kites. In contrast, juvenile kites experienced the highest survival during the event, although our data suggest greater annual variability than can be explained by the event alone. We found no evidence of an effect of the high water event on nest success or number of young per successful nest. Nest success was highest during the event in the southern portion of the range but was quite similar to other years, both before and after the event. Our data do indicate a substantial shift in the spatial distribution of nesting birds. During the event, nesting activity shifted to higher elevations (i.e., shallower water) in the major nesting areas of the Everglades region. Nesting also occurred in Big Cypress National Preserve during the event, which is typically too dry to support nesting kites. Thus, our data indicate a potential short-term benefit of increased juvenile survival and an expansion of nesting habitat. However, the deterioration of habitat quality from prolonged high water precludes any recommendation for such conditions to be maintained for extended periods. ?? 2002, The Society of Wetland Scientists.

Kite-flying: a unique but dangerous mode of electrical injury in children.

PubMed

Tiwari, V K; Sharma, D

1999-09-01

A retrospective study was conducted to evaluate the cause of a sudden rise in number of pediatric admissions with electrical injuries at our centre during the year 1998. In evaluating the cause, six out of twelve admissions were found to be related to kite-flying which is a popular sport during the months of June, July, August and September. In two out of six cases current travelled directly through the string of the kite. In two others, flame burns occured following ignition of clothing. Another patient had contact with wire through a metal rod. In the last case, arcing pulled the hand of the patient leading to direct contact with wire. The average burns size was approximately 31% body surface area (BSA), with all patients having burns over the palmar aspect of at least one hand. No patient required amputation for the injuries. In this article, attention has been focussed on the various modes of electrical injuries associated with kite-flying and some measures have been advised to avoid such accidents.

Cluster of atherosclerosis in a captive population of black kites (Milvus migrans subsp.) in France and effect of nutrition on the plasma lipid profile.

PubMed

Facon, Charles; Beaufrere, Hugues; Gaborit, Christophe; Albaric, Olivier; Plassiart, Georges; Ammersbach, Melanie; Liegeois, Jean-Louis

2014-03-01

From January 2010 to March 2013, a captive colony of 83 black kites (Milvus migrans subsp.) in France experienced increased mortality related to atherosclerosis with an incidence of 4.4% per year. On histopathology, all kites had advanced atherosclerotic lesions, with several birds presenting abdominal hemorrhage and aortic rupture. In January 2012, a dietary change was instituted and consisted of introducing fish into the kites' diet. During the following 15 mo, the plasma lipid profile was monitored as well as body weight, food offered, and flight activity. Total and low-density lipoprotein cholesterol initially increased, but in December 2012 and March 2013, an overall decrease from initial values was observed. High-density lipoprotein cholesterol also increased during this period. Despite positive plasma lipid changes induced by dietary modifications, there was no decrease in mortality from atherosclerosis, which was probably associated with the severity of the atherosclerotic lesions at time of dietary management. However, owing to the long and progressive development of atherosclerotic lesions, long-term beneficial effects are probable. This report suggests that black kites are particularly susceptible to atherosclerosis and aortic dissection in captivity. To prevent degenerative diseases associated with captivity in birds of prey, species-specific lifestyle and dietary requirements and susceptibility to these diseases should be considered.

Hand Injuries by the Killer Kite Manja and Their Management.

PubMed

Mir, Mohd Altaf; Ali, Adil Mahmud; Yaseen, Mohd; Khan, Arshad Hafeez

2017-05-01

Although hand injuries due to kite strings seem to be trivial, these injuries could be serious enough to lose the function of hand. This case series in the division of Plastic and Reconstructive Surgery of our institution from August 2014 to January 2016 evaluated the clinic-etiological profile, severity and management of hand injuries due to kite strings assessed clinically and radiologically. Eleven patients reported kite related injuries during two years, and 5 presented during 17 months. Of 11 patients, 8 were male and 3 were female with a M:F ratio of 2.66:1. The majority of patients presented with the mean age of 19.9±4.27 years. Eight patients presented acutely to the emergency while 3 believed the injury to be trivial and had delayed presentation. Injuries in the right hand were 8 and 3 in the left hand. Seven patients had injuries in zone II of the hand while 4 presented with zone III injuries. Total number of injured digits was 14 (1.4±1.11), total number of injured tendons was 26 (2.36±2.18), only one patient had nerve injury (mean=0.09), and no patient had any major vessel injury. So strict attention to safety measures and parental/guardian supervision while flying kites can avoid many preventable injuries to life and limb and also let the sport be an enjoyable and safe.

Kite: status of the external metrology testbed for SIM

NASA Astrophysics Data System (ADS)

Dekens, Frank G.; Alvarez-Salazar, Oscar S.; Azizi, Alireza; Moser, Steven J.; Nemati, Bijan; Negron, John; Neville, Timothy; Ryan, Daniel

2004-10-01

Kite is a system level testbed for the External Metrology System of the Space Interferometry Mission (SIM). The External Metrology System is used to track the fiducials that are located at the centers of the interferometer's siderostats. The relative changes in their positions needs to be tracked to an accuracy of tens of picometers in order to correct for thermal deformations and attitude changes of the spacecraft. Because of the need for such high precision measurements, the Kite testbed was build to test both the metrology gauges and our ability to optically model the system at these levels. The Kite testbed is a redundant metrology truss, in which 6 lengths are measured, but only 5 are needed to define the system. The RMS error between the redundant measurements needs to be less than 140pm for the SIM Wide-Angle observing scenario and less than 8 pm for the Narrow-Angle observing scenario. With our current testbed layout, we have achieved an RMS of 85 pm in the Wide-Angle case, meeting the goal. For the Narrow-Angle case, we have reached 5.8 pm, but only for on-axis observations. We describe the testbed improvements that have been made since our initial results, and outline the future Kite changes that will add further effects that SIM faces in order to make the testbed more representative of SIM.

Total edge irregularity strength of (n,t)-kite graph

NASA Astrophysics Data System (ADS)

Winarsih, Tri; Indriati, Diari

2018-04-01

Let G(V, E) be a simple, connected, and undirected graph with vertex set V and edge set E. A total k-labeling is a map that carries vertices and edges of a graph G into a set of positive integer labels {1, 2, …, k}. An edge irregular total k-labeling λ :V(G)\\cup E(G)\\to \\{1,2,\\ldots,k\\} of a graph G is a labeling of vertices and edges of G in such a way that for any different edges e and f, weights wt(e) and wt(f) are distinct. The weight wt(e) of an edge e = xy is the sum of the labels of vertices x and y and the label of the edge e. The total edge irregularity strength of G, tes(G), is defined as the minimum k for which a graph G has an edge irregular total k-labeling. An (n, t)-kite graph consist of a cycle of length n with a t-edge path (the tail) attached to one vertex of a cycle. In this paper, we investigate the total edge irregularity strength of the (n, t)-kite graph, with n > 3 and t > 1. We obtain the total edge irregularity strength of the (n, t)-kite graph is tes((n, t)-kite) = \\lceil \\frac{n+t+2}{3}\\rceil .

Project KITES: Kids Interacting with Technology and Education Students.

ERIC Educational Resources Information Center

Taylor, Harriet G.; Stuhlmann, Janice M.

Faculty and administrators at the College of Education at Louisiana State University recognized the need to incorporate technology into all of their programs. Project KITES (Kids Interacting with Technology and Education Students) was developed to give students just beginning their professional education component real experiences with children…

Solar radio-transmitters on snail kites in Florida

USGS Publications Warehouse

Snyder, N.F.R.; Beissinger, S.R.; Fuller, M.R.

1989-01-01

The effectiveness and safety of one- and two-stage solar radio-transmitters in tracking the movements and survival of adult and fledgling Snail Kites (Rostrhamus sociabilis) were evaluated between 1979 and 1983 in southern Florida. Transmitters were attached to birds with back-pack arrangements using teflon ribbon straps. Accessory plastic shields minimized feather coverage of the solar cells. Intact transmitters were seen on birds up to 47 mo after installation. Operating lives ranged from 8 to 21 mo for one-stage, and 10 to 14 mo for two-stage transmitters. Because survival of adult and nestling radio-marked kites was high, we conclude that our transmitter-attachment method had little effect on the birds.

A tool for simulating collision probabilities of animals with marine renewable energy devices.

PubMed

Schmitt, Pál; Culloch, Ross; Lieber, Lilian; Molander, Sverker; Hammar, Linus; Kregting, Louise

2017-01-01

The mathematical problem of establishing a collision probability distribution is often not trivial. The shape and motion of the animal as well as of the the device must be evaluated in a four-dimensional space (3D motion over time). Earlier work on wind and tidal turbines was limited to a simplified two-dimensional representation, which cannot be applied to many new structures. We present a numerical algorithm to obtain such probability distributions using transient, three-dimensional numerical simulations. The method is demonstrated using a sub-surface tidal kite as an example. Necessary pre- and post-processing of the data created by the model is explained, numerical details and potential issues and limitations in the application of resulting probability distributions are highlighted.

Kite Aerial Photography (KAP) as a Tool for Field Teaching

ERIC Educational Resources Information Center

Sander, Lasse

2014-01-01

Kite aerial photography (KAP) is proposed as a creative tool for geography field teaching and as a medium to approach the complexity of readily available geodata. The method can be integrated as field experiment, surveying technique or group activity. The acquired aerial images can instantaneously be integrated in geographic information systems…

Interactive effects of senescence and natural disturbance on the annual survival probabilities of snail kites

USGS Publications Warehouse

Reichert, Brian E.; Martin, J.; Kendall, William L.; Cattau, Christopher E.; Kitchens, Wiley M.

2010-01-01

Individuals in wild populations face risks associated with both intrinsic (i.e. aging) and external (i.e. environmental) sources of mortality. Condition-dependent mortality occurs when there is an interaction between such factors; however, few studies have clearly demonstrated condition-dependent mortality and some have even argued that condition-dependent mortality does not occur in wild avian populations. Using large sample sizes (2084 individuals, 3746 re-sights) of individual-based longitudinal data collected over a 33 year period (1976-2008) on multiple cohorts, we used a capture-mark-recapture framework to model age-dependent survival in the snail kite Rostrhamus sociabilis plumbeus population in Florida. Adding to the growing amount of evidence for actuarial senescence in wild populations, we found evidence of senescent declines in survival probabilities in adult kites. We also tested the hypothesis that older kites experienced condition-dependent mortality during a range-wide drought event (2000-2002). The results provide convincing evidence that the annual survival probability of senescent kites was disproportionately affected by the drought relative to the survival probability of prime-aged adults. To our knowledge, this is the first evidence of condition-dependent mortality to be demonstrated in a wild avian population, a finding which challenges recent conclusions drawn in the literature. Our study suggests that senescence and condition-dependent mortality can affect the demography of wild avian populations. Accounting for these sources of variation may be particularly important to appropriately compute estimates of population growth rate, and probabilities of quasi-extinctions.

About Our Agency | National Oceanic and Atmospheric Administration

Science.gov Websites

our agency Mission & vision Our commitment to science Our history Leadership RDML Tim Gallaudet our evolving planet View our featured experts Our history A weather kite being prepared for launching with kite-reel house in the background. NOAA's history is an intrinsic part of the history of the

Exploring Adolescents' Multimodal Responses to "The Kite Runner": Understanding How Students Use Digital Media for Academic Purposes

ERIC Educational Resources Information Center

Jocius, Robin

2013-01-01

This qualitative study explores how adolescent high school students in an AP English class used multiple forms of media (the internet, digital video, slide show software, video editing tools, literary texts, and writing) to respond to and analyze a contemporary novel, "The Kite Runner". Using a multimodal analysis framework, the author explores…

Analysis of Hassan's Tragedy in "The Kite Runner" from the Three-Dimensional Ethical Perspective

ERIC Educational Resources Information Center

Yuan-yuan, Peng

2018-01-01

Hassan in "The Kite Runner" was brave, kind-hearted and loyal, but he still ended up with misery. From the three dimensional ethical perspective, Hassan's tragedy is not only greatly related to national and religious ethics, but also influenced by deformed family ethics. Thus it can be seen that national discrimination and religious…

The Artist Teacher Uses Proportions, the Math Teacher Helps Students Understand the How and Why, Fractions Fly the Kites

ERIC Educational Resources Information Center

Autin, Gwen H.

2007-01-01

Mathematics and art are often considered opposites in the traditional curriculum. In this project with fourth graders, mathematics and art provided a springboard for using fractions, in particular, the multiplication of fractions, using Chinese kites. The project began with a discussion of, "What does an artist really do in a mathematics…

MEASUREMENTS OF NON-METHANE VOLATILE ORGANIC COMPOUNDS IN THE LOWER TROPOSPHERE FROM TETHERED BALLOON AND KITE SAMPLING PLATFORMS BY INTERNAL STANDARD CALIBRATION USING AMBIENT CFC REFERENCE COMPOUNDS

EPA Science Inventory

A new analytical approach for the sampling and analysis of volatile organic compounds (VOCs) from sampling platforms used in the vertical profiling of the lower troposphere, such as kites, balloons, and remotely piloted vehicles will be developed. These sampling platforms a...

Environmental influences on the nesting phenology and productivity of Mississippi Kites (Ictinia mississippiensis)

USGS Publications Warehouse

Welch, Brandi C.; Boal, Clint W.; Skipper, Ben R.

2017-01-01

Identifying sources of annual variation in the reproductive success of a species may provide valuable insights into how the species may be affected by future environmental or climatic conditions. We examined annual variation in the nesting phenology, productivity, and apparent nest success of Mississippi Kites (Ictinia mississippiensis), a species common in urban areas in the southern Great Plains, from May through August. We monitored 498 Mississippi Kite nesting attempts in Lubbock, Texas, USA, between 2004 and 2015, from which we modeled daily survival rate as a function of local weather conditions, drought severity, and the state of the El Niño Southern Oscillation. We observed significant annual variation in median incubation initiation date (range = May 20 to June 5), the probability of nest success (range = 0.31–0.90), and productivity (range = 0.25–1.00 fledglings per nest). Our models of daily survival rate suggested that higher daily temperatures, severe storm events, extreme drought conditions, and La Niña events negatively influenced nest survival. These results suggest that increasing storm frequency and higher temperatures associated with climate change are likely to decrease the nesting success of Mississippi Kites in the southern Great Plains.

Demography, environmental uncertainty, and the evolution of mate desertion in the snail kite

USGS Publications Warehouse

Beissinger, S.R.

1986-01-01

The Snail Kite (Rostrhamus sociabilis), an endangered hawk, has a unique mating system in Florida (Beissinger and Snyder 1987): when food is abundant, males or females desert their mates at nearly equal frequency (ambisexual mate desertion) in the midst of a nesting cycle. I examined the demographic and environmental constraints selecting for a clutch size that permits one parent to desert, yet optimizes the number of offspring produced by each parent. Demographic studies, conducted from 1979-1983, indicated that kites have (1) a very high nest failure rate (?= 68%) due most often to unstable nest sites and predation, (2) a variable nesting season (5-10 mo/yr), (3) an early age of first reproduction for a bird this size (10 mo), (4) a high degree of iteroparity (double and potentially triple clutching within a season), and (5) unstable populations. Both nesting success and population size were directly related to Everglades water levels and resultant snail densities. Kites responded to large annual changes in food abundance, not by adjusting clutch size but by deserting their mates and presumably attempting to renest. Kite demographic traits appear to be adaptations to or results of an uncertain environment. Based on 67 yr of Everglades water levels, environmental predictability, measured by spectral analysis and Colwell's (1974) index, was low and influenced by water management regimes: (1) water levels were lowered, (2) annual variation in levels increased and annual cycles became stronger, (3) the period length of long-term drought-flood cycles shifted from 10 or more yr toward 5 yr, and (4) levels became a less predictive cue for favorable nesting conditions. A potential evolutionary pathway from biparental care to mate desertion in Snail Kites is proposed. It is unlikely that mate desertion evolved solely from a context of conflict between the sexes, because kite nesting success is so low that it is probably maladaptive for a parent to desert and jeopardize the survival of any of its first brood. Instead, mate desertion behavior probably evolved in response to a smaller average clutch size; this would allow females to be highly iteroparous and avoid the costs of overinvestment, and should be strongly favored in a highly uncertain environment. Analysis of clutches in museum collections suggests that an apparent decline in clutch size may have occurred in Florida during the past century. The potential for ambisexual mate desertion to occur in other vertebrates is during the past century. The potential for ambisexual mate desertion to occur in other vertebrates is examined.

Large HAWT wake measurement and analysis

NASA Technical Reports Server (NTRS)

Miller, A. H.; Wegley, H. L.; Buck, J. W.

1995-01-01

From the theoretical fluid dynamics point of view, the wake region of a large horizontal-axis wind turbine has been defined and described, and numerical models of wake behavior have been developed. Wind tunnel studies of single turbine wakes and turbine array wakes have been used to verify the theory and further refine the numerical models. However, the effects of scaling, rotor solidity, and topography on wake behavior are questions that remain unanswered. In the wind tunnel studies, turbines were represented by anything from scaled models to tea strainers or wire mesh disks whose solidity was equivalent to that of a typical wind turbine. The scale factor compensation for the difference in Reynolds number between the scale model and an actual turbine is complex, and not typically accounted for. Though it is wise to study the simpler case of wakes in flat topography, which can be easily duplicated in the wind tunnel, current indications are that wind turbine farm development is actually occurring in somewhat more complex terrain. Empirical wake studies using large horizontal-axis wind turbines have not been thoroughly composited, and, therefore, the results have not been applied to the well-developed theory of wake structure. The measurement programs have made use of both in situ sensor systems, such as instrumented towers, and remote sensors, such as kites and tethered, balloonborne anemometers. We present a concise overview of the work that has been performed, including our own, which is based on the philosophy that the MOD-2 turbines are probably their own best detector of both the momentum deficit and the induced turbulence effect downwind. Only the momentum deficit aspects of the wake/machine interactions have been addressed. Both turbine power output deficits and wind energy deficits as measured by the onsite meteorological towers have been analyzed from a composite data set. The analysis has also evidenced certain topographic influences on the operation of spatially diverse wind turbines.

Large HAWT wake measurement and analysis

NASA Astrophysics Data System (ADS)

Miller, A. H.; Wegley, H. L.; Buck, J. W.

1995-05-01

From the theoretical fluid dynamics point of view, the wake region of a large horizontal-axis wind turbine has been defined and described, and numerical models of wake behavior have been developed. Wind tunnel studies of single turbine wakes and turbine array wakes have been used to verify the theory and further refine the numerical models. However, the effects of scaling, rotor solidity, and topography on wake behavior are questions that remain unanswered. In the wind tunnel studies, turbines were represented by anything from scaled models to tea strainers or wire mesh disks whose solidity was equivalent to that of a typical wind turbine. The scale factor compensation for the difference in Reynolds number between the scale model and an actual turbine is complex, and not typically accounted for. Though it is wise to study the simpler case of wakes in flat topography, which can be easily duplicated in the wind tunnel, current indications are that wind turbine farm development is actually occurring in somewhat more complex terrain. Empirical wake studies using large horizontal-axis wind turbines have not been thoroughly composited, and, therefore, the results have not been applied to the well-developed theory of wake structure. The measurement programs have made use of both in situ sensor systems, such as instrumented towers, and remote sensors, such as kites and tethered, balloonborne anemometers. We present a concise overview of the work that has been performed, including our own, which is based on the philosophy that the MOD-2 turbines are probably their own best detector of both the momentum deficit and the induced turbulence effect downwind. Only the momentum deficit aspects of the wake/machine interactions have been addressed. Both turbine power output deficits and wind energy deficits as measured by the onsite meteorological towers have been analyzed from a composite data set. The analysis has also evidenced certain topographic influences on the operation of spatially diverse wind turbines.

Habitat Suitability Index Models: Black-shouldered kite

USGS Publications Warehouse

Faanes, Craig A.; Howard, Rebecca J.

1987-01-01

A review and synthesis of existing information were used to develop a model for evaluating black-shouldered kite habitat quality. The model is scaled to produce an index between 0 (unsuitable habitat) to 1.0 (optimal habitat). Habitat suitability index models are designed for use with the Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service. Guidelines for model application are provided.

IET. Snaptran. Flying a kite in the service of science. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

IET. Snaptran. Flying a kite in the service of science. Doug Wenzel and Jon Hurd obtain weather data on east side of IET as part of Snaptran experiment. tank building (TAN-627) and movable building (TAN-624) at left. Stack and ANP duct at right. Photographer: Farmer. Date: September 27, 1965. INEEL negative no. 65-4986 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

Influence of various land uses on windbreak selection by nesting Mississippi kites

USGS Publications Warehouse

Love, Diane; Grzybowski, Joseph A.; Knopf, Fritz L.

1985-01-01

Contemporary land-use practices have dramatically altered breeding habitats of birds of prey (Cramp, pp. 9-11 in World Conf. Birds of Prey, R. D. Chancellor, ed., ICPB, London, England, 1977). Some land uses appear to influence strongly both the nesting activity (White, Trans. North Am. Wild. Nat. Resour. Conf. 39:301-312, 1974) and abundance (Olendorff and Stoddart, pp. 44-48 in Management of Raptors, F. N. Jamerstrom, B. E. Harrel, and R. R. Olendorff, eds., Proc. Conf. Raptor Conserv. Tech., Raptor Rep. 2, Fort Collins, Colorado, 1974) of raptors. The Mississippi Kite (Ictinia mississippiensis) is a locally common raptor of the south-central plains of North America. In the prairie grasslands of western Oklahoma and south-western Kansas, kites commonly nest in tree plantings designed as windbreaks, irrespective of windbreak width, age, or tree species compositions (Parker, Ph.D. Diss., Univ. Kansas, Lawrence, Kansas, 1974; Love and Knopf, Proc. Ann. Meet. For. Comm. Great Plains Agric. Counc. 30:69-77, 1978). Much of the potential nesting habitat within this region, however, is not used by kits (Parker and Ogden, Am. Birds 33:119-129, 1979). In this paper, we assess the potential influence of various land-use practices on windbreak selection by nesting Mississippi Kites.

Importance of well-designed monitoring programs for the conservation of endangered species: case study of the Snail Kite

USGS Publications Warehouse

Martin, J.; Kitchens, W.M.; Hines, J.E.

2007-01-01

Monitoring natural populations is often a necessary step to establish the conservation status of species and to help improve management decisions. Nevertheless, many monitoring programs do not effectively address primary sources of variability in monitoring data, which ultimately may limit the utility of monitoring in identifying declines and improving management. To illustrate the importance of taking into account detectability and spatial variation, we used a recently proposed estimator of abundance (superpopulation estimator) to estimate population size of and number of young produced by the Snail Kite (Rostrhamus sociabilis plumbeus) in Florida. During the last decade, primary recovery targets set by the U.S. Fish and Wildlife Service for the Snail Kite that were based on deficient monitoring programs (i.e., uncorrected counts) were close to being met (by simply increasing search effort during count surveys). During that same period, the Snail Kite population declined dramatically (by 55% from 1997 to 2005) and the number of young decreased by 70% between 1992?1998 and 1999?2005. Our results provide a strong practical case in favor of the argument that investing a sufficient amount of time and resources into designing and implementing monitoring programs that carefully address detectability and spatial variation is critical for the conservation of endangered species.

Superpredator proximity and landscape characteristics alters nest site selection and breeding success of a subordinate predator.

PubMed

Atuo, Fidelis Akunke; O'Connell, Timothy John

2018-03-01

Selecting nesting habitat that minimizes predation risk but maximizes foraging success is one of the most important decisions in avian life history. This takes on added complexity when a predator is faced with the challenge of avoiding fellow predators. We assessed the importance of local and landscape vegetation, food abundance, and predation risk on nest site selection and nest survival in a subordinate raptor (Mississippi Kite; Ictinia mississippiensis) nesting in proximity to two superpredators, Red-tailed hawk (Buteo jamaicensis) and Great horned owl (Bubo virginianus). All three species nested in trees in a grassland landscape. In this landscape, kites favored upland trees and shrubs, avoiding their more typical riparian forest association elsewhere in the species' range. Compared to random conditions, kites selected nest sites with high tree density and more closed canopy in the surrounding area. Mississippi Kite selection was not related to food abundance but could be explained by the presence of superpredators (i.e., hawks and owls) selecting riparian woodland for their nests. Nest survival declined with proximity to superpredator nesting sites. Overall, our study demonstrates how landscape structure and superior predators shapes predation risk for subordinate predators. Our results emphasize the importance of spatial heterogeneity in presenting opportunities for subordinate predators to coexist in a landscape with important superpredators.

The epidemiology of injury among surfers, kite surfers and personal watercraft riders: wind and waves.

PubMed

Pikora, Terri J; Braham, Rebecca; Mills, Christina

2012-01-01

The objective of this review was to summarize the epidemiological literature for surfboard riding (surfing), kite surfing and personal watercraft (PWC) riding injuries and describe the incidence and nature of these injuries, common risk factors, and strategies for prevention. The databases searched for relevant publications included Medline, ScienceDirect, ProQuest International, PubMed, Academic Search Premier as well as Google Scholar to identify additional, non-indexed studies. Overall, there was a lack of good quality descriptive studies for these three sports and many of the studies reviewed involved the use of administrative datasets or case-series designs. Among the few studies to provide incidence estimates, there were inconsistencies in how injury was defined, the inclusion criteria, and the reporting of incidence rates, making comparisons within and between the sports difficult. While the reported incidence rates were generally low, head and lower extremity injuries were common across all three sports. Only two studies reported evidence for postulated risk factors. Bigger waves and surfing over rock or reef sea floor increased the risk of injury among competitive surfers, while older age and having more experience increased the risk of significant injuries among recreational surfers. No evaluations of preventative measures were identified. This review demonstrates the need for well-designed epidemiological research, especially studies that focus on the accurate measurement and description of incidence, nature, severity and circumstances of injuries. Once this has occurred, interventions targeted at reducing the incidence of injuries among these sports can be designed, implemented and evaluated. Copyright © 2012 S. Karger AG, Basel.

Autonomous Aerial Sensors for Wind Power Meteorology

NASA Astrophysics Data System (ADS)

Giebel, Gregor; Schmidt Paulsen, Uwe; Reuder, Joachim; La Cour-Harbo, Anders; Thomsen, Carsten; Bange, Jens; Buschmann, Marco

2010-05-01

This poster describes a new approach for measurements in wind power meteorology using small unmanned flying platforms. During a week of flying a lighter-than-air vehicle, two small electrically powered aeroplanes and a larger helicopter at the Risø test station at Høvsøre, we will compare wind speed measurements with fixed mast and LIDAR measurements, investigate optimal flight patterns for each measurement task, and measure other interesting meteorological features like the air-sea boundary in the vicinity of the wind farm. In order to prepare the measurement campaign, a workshop is held, soliciting input from various communities. Large-scale wind farms, especially offshore, need an optimisation between installed wind power density and the losses in the wind farm due to wake effects between the turbines. While the wake structure behind single wind turbines onshore is fairly well understood, there are different problems offshore, thought to be due mainly to the low turbulence. Good measurements of the wake and wake structure are not easy to come by, as the use of a met mast is static and expensive, while the use of remote sensing instruments either needs significant access to the turbine to mount an instrument, or is complicated to use on a ship due to the ship's own movement. In any case, a good LIDAR or SODAR will cost many tens of thousands of euros. Another current problem in wind energy is the coming generation of wind turbines in the 10-12 MW class, with tip heights of over 200 m. Very few measurement masts exist to verify our knowledge of atmospheric physics - all that is known is that the boundary layer description we used so far is not valid any more. Here, automated Unmanned Aerial Vehicles (UAVs) could be used as either an extension of current high masts or to build a network of very high ‘masts' in a region of complex terrain or coastal flow conditions. In comparison to a multitude of high masts, UAVs could be quite cost-effective. In order to test this assumption and to test the limits of UAVs for wind power meteorology, this project assembles four different UAVs from four participating groups. Risø will build a lighter-than-air kite with a long tether, Bergen University flies a derivative of the Funjet, a pusher airplane below 1 kg total weight, Mavionics or TU Braunschweig flies the Carolo, a 2m wide two prop model with a pitot tube on the nose, and Aalborg University will use a helicopter for their part. All those platforms will be flown during one week at the Danish national test station for large wind turbines at Høvsøre. The site is strongly instrumented, with 6 masts reaching up to 167m. The comparison of wind speed measurements from planes and fixed masts should give an indication of the accuracy of the measured wind field. A workshop is planned as preparation, where everyone with an interest in the program can give input.

The Coast Artillery Journal. Volume 58, Number 5, May 1923

DTIC Science & Technology

1923-05-01

defense by pursuit planes, antiaircraft artillery, machine guns and searchlights, and by captive balloon and kite en- tanglements in the rear areas...Airplane areas. 4. Balloon areas, containing balloon and kite entanglements with auxiliary searchlights, guns, and machine guns if available. 5. A belt of...liaison with company headquarters and the sections should be kept up by means of runners . d. The Section The section is the smallest tactical unit of

a Method for Simultaneous Aerial and Terrestrial Geodata Acquisition for Corridor Mapping

NASA Astrophysics Data System (ADS)

Molina, P.; Blázquez, M.; Sastre, J.; Colomina, I.

2015-08-01

In this paper, we present mapKITE, a new mobile, simultaneous terrestrial and aerial, geodata collection and post-processing method. On one side, the method combines a terrestrial mobile mapping system (TMMS) with an unmanned aerial mapping one, both equipped with remote sensing payloads (at least, a nadir-looking visible-band camera in the UA) by means of which aerial and terrestrial geodata are acquired simultaneously. This tandem geodata acquisition system is based on a terrestrial vehicle (TV) and on an unmanned aircraft (UA) linked by a 'virtual tether', that is, a mechanism based on the real-time supply of UA waypoints by the TV. By means of the TV-to-UA tether, the UA follows the TV keeping a specific relative TV-to-UA spatial configuration enabling the simultaneous operation of both systems to obtain highly redundant and complementary geodata. On the other side, mapKITE presents a novel concept for geodata post-processing favoured by the rich geometrical aspects derived from the mapKITE tandem simultaneous operation. The approach followed for sensor orientation and calibration of the aerial images captured by the UA inherits the principles of Integrated Sensor Orientation (ISO) and adds the pointing-and-scaling photogrammetric measurement of a distinctive element observed in every UA image, which is a coded target mounted on the roof of the TV. By means of the TV navigation system, the orientation of the TV coded target is performed and used in the post-processing UA image orientation approach as a Kinematic Ground Control Point (KGCP). The geometric strength of a mapKITE ISO network is therefore high as it counts with the traditional tie point image measurements, static ground control points, kinematic aerial control and the new point-and-scale measurements of the KGCPs. With such a geometry, reliable system and sensor orientation and calibration and eventual further reduction of the number of traditional ground control points is feasible. The different technical concepts, challenges and breakthroughs behind mapKITE are presented in this paper, such as the TV-to-UA virtual tether and the use of KGCP measurements for UA sensor orientation. In addition, the use in mapKITE of new European GNSS signals such as the Galileo E5 AltBOC is discussed. Because of the critical role of GNSS technologies and the potential impact on the corridor mapping market, the European Commission and the European GNSS Agency, in the frame of the European Union Framework Programme for Research and Innovation "Horizon 2020," have recently awarded the "mapKITE" project to an international consortium of organizations coordinated by GeoNumerics S.L.

Individual Movement Strategies Revealed through Novel Clustering of Emergent Movement Patterns

NASA Astrophysics Data System (ADS)

Valle, Denis; Cvetojevic, Sreten; Robertson, Ellen P.; Reichert, Brian E.; Hochmair, Hartwig H.; Fletcher, Robert J.

2017-03-01

Understanding movement is critical in several disciplines but analysis methods often neglect key information by adopting each location as sampling unit, rather than each individual. We introduce a novel statistical method that, by focusing on individuals, enables better identification of temporal dynamics of connectivity, traits of individuals that explain emergent movement patterns, and sites that play a critical role in connecting subpopulations. We apply this method to two examples that span movement networks that vary considerably in size and questions: movements of an endangered raptor, the snail kite (Rostrhamus sociabilis plumbeus), and human movement in Florida inferred from Twitter. For snail kites, our method reveals substantial differences in movement strategies for different bird cohorts and temporal changes in connectivity driven by the invasion of an exotic food resource, illustrating the challenge of identifying critical connectivity sites for conservation in the presence of global change. For human movement, our method is able to reliably determine the origin of Florida visitors and identify distinct movement patterns within Florida for visitors from different places, providing near real-time information on the spatial and temporal patterns of tourists. These results emphasize the need to integrate individual variation to generate new insights when modeling movement data.

Supplementary feeding and endoparasites in threatened avian scavengers: Coprologic evidence from red kites in their wintering stronghold.

PubMed

Blanco, Guillermo; Cardells, Jesús; Garijo-Toledo, María M

2017-05-01

Many obligate and facultative avian scavengers are increasingly dependent on food provided in supplementary feeding stations (SFS), which are managed for the conservation of these species. Deliberate feeding can influence disease-related host demography and population dynamics through physiological changes and density-dependent parasite acquisition and transmission, but information on this threat to avian scavengers is scarce. Due to their effects on host aggregation and density, we hypothesised that the predictability and concentration of food in SFS can exacerbate parasite infection. This hypothesis was tested by comparing the prevalence, richness, abundance and mixed infection of endoparasites (coccidia and helminths) in red kites Milvus milvus foraging on livestock carcasses (mostly of pigs and poultry) in overcrowded and confined conditions at SFS, relative to those foraging alone or in small groups on wild prey unevenly randomly distributed within large areas during winter, mostly wild rabbits (Oryctolagus cuniculus). No clear differences were found between areas with and without SFS in the prevalence and abundance of oocyst of Eimeria. This coccidian genus appears to include parasites of the prey rather than the raptors, thus representing parasite transport or pseudo-parasitism rather than actual parasitism in the kites. A higher prevalence and richness of helminths, as well as mixed infections with several phyla, was found in kites exploiting SFS than in those feeding on wild prey in the area without SFS. The unsanitary conditions derived from the stack of livestock carcasses and the contamination of carrion with the faeces of multiple scavenger hosts can increase the accumulation and persistence of helminths eggs and intermediate hosts. The regular use and frequent confinement of large numbers of red kites at SFS can promote the spread of parasites to a large proportion of the European breeding population distributed across Spain during the winter. We encourage that carcasses of free roaming livestock can be left in the countryside, as well as the conservation management of wildlife exploited as food by red kites (especially wild rabbits), to attempt avoiding overcrowded and confined conditions at SFS. Further research is required to assess the impact of deliberate feeding on the spread of parasites and other disease agents in the threatened species SFS are intended to favour. Copyright © 2017 Elsevier Inc. All rights reserved.

Affinity for natal environments by dispersers impacts reproduction and explains geographical structure of a highly mobile bird.

PubMed

Fletcher, Robert J; Robertson, Ellen P; Wilcox, Rebecca C; Reichert, Brian E; Austin, James D; Kitchens, Wiley M

2015-09-07

Understanding dispersal and habitat selection behaviours is central to many problems in ecology, evolution and conservation. One factor often hypothesized to influence habitat selection by dispersers is the natal environment experienced by juveniles. Nonetheless, evidence for the effect of natal environment on dispersing, wild vertebrates remains limited. Using 18 years of nesting and mark-resight data across an entire North American geographical range of an endangered bird, the snail kite (Rostrhamus sociabilis), we tested for natal effects on breeding-site selection by dispersers and its consequences for reproductive success and population structure. Dispersing snail kites were more likely to nest in wetlands of the same habitat type (lacustrine or palustrine) as their natal wetland, independent of dispersal distance, but this preference declined with age and if individuals were born during droughts. Importantly, dispersing kites that bred in natal-like habitats had lower nest success and productivity than kites that did not. These behaviours help explain recently described population connectivity and spatial structure across their geographical range and reveal that assortative breeding is occurring, where birds are more likely to breed with individuals born in the same wetland type as their natal habitat. Natal environments can thus have long-term and large-scale effects on populations in nature, even in highly mobile animals. © 2015 The Author(s).

Can Ingestion of Lead Shot and Poisons Change Population Trends of Three European Birds: Grey Partridge, Common Buzzard, and Red Kite?

PubMed Central

Meyer, Carolyn B.; Meyer, Joseph S.; Francisco, Alex B.; Holder, Jennifer; Verdonck, Frederik

2016-01-01

Little is known about the magnitude of the effects of lead shot ingestion alone or combined with poisons (e.g., in bait or seeds/granules containing pesticides) on population size, growth, and extinction of non-waterbird avian species that ingest these substances. We used population models to create example scenarios demonstrating how changes in these parameters might affect three susceptible species: grey partridge (Perdix perdix), common buzzard (Buteo buteo), and red kite (Milvus milvus). We added or subtracted estimates of mortality due to lead shot ingestion (4–16% of mortality, depending on species) and poisons (4–46% of mortality) reported in the UK or France to observed mortality of studied populations after models were calibrated to observed population trends. Observed trends were decreasing for partridge (in continental Europe), stable for buzzard (in Germany), and increasing for red kite (in Wales). Although lead shot ingestion and poison at modeled levels did not change the trend direction for the three species, they reduced population size and slowed population growth. Lead shot ingestion at modeled rates reduced population size of partridges by 10%, and when combined with bait and pesticide poisons, by 18%. For buzzards, decrease in mean population size by lead shot and poisons combined was much smaller (≤ 1%). The red kite population has been recovering; however, modeled lead shot ingestion reduced its annual growth rate from 6.5% to 4%, slowing recovery. If mortality from poisoned baits could be removed, the kite population could potentially increase at a rapid annual rate of 12%. The effects are somewhat higher if ingestion of these substances additionally causes sublethal reproductive impairment. These results have uncertainty but suggest that declining or recovering populations are most sensitive to lead shot or poison ingestion, and removal of poisoned baits can have a positive impact on recovering raptor populations that frequently feed on carrion. PMID:26799815

Development of a Novel Escherichia coli-Kocuria Shuttle Vector Using the Cryptic pKPAL3 Plasmid from K. palustris IPUFS-1 and Its Utilization in Producing Enantiopure (S)-Styrene Oxide.

PubMed

Toda, Hiroshi; Itoh, Nobuya

2017-01-01

The novel cryptic pKPAL3 plasmid was isolated from the Gram-positive microorganism Kocuria palustris IPUFS-1 and characterized in detail. pKPAL3 is a circular plasmid that is 4,443 bp in length. Open reading frame (ORF) and homology search analyses indicated that pKPAL3 possesses four ORFs; however, there were no replication protein coding genes predicted in the plasmid. Instead, there were two nucleotide sequence regions that showed significant identities with untranslated regions of K. rhizophila DC2201 (NBRC 103217) genomic sequences, and these sequences were essential for autonomous replication of pKPAL3 in Kocuria cells. Based on these findings, we constructed the novel Escherichia coli - Kocuria shuttle vectors pKITE301 (kanamycin resistant) and pKITE303 (thiostrepton resistant) from pKPAL3. The copy numbers of the constructed shuttle vectors were estimated to be 20 per cell, and they exhibited low segregation stability in Kocuria transformant cells in the absence of antibiotics. Moreover, constructed vectors showed compatibility with the other K. rhizophila shuttle vector pKITE103. We successfully expressed multiple heterologous genes, including the styrene monooxygenase gene from Rhodococcus sp. ST-10 ( rhsmo ) and alcohol dehydrogenase gene from Leifsonia sp. S749 ( lsadh ), in K . rhizophila DC2201 using the pKITE301P and pKITE103P vectors under the control of the glyceraldehyde 3-phosphate dehydrogenase ( gapdh ) promotor. The RhSMO-LSADH co-expressing K. rhizophila was used as a biocatalyst in an organic solvent-water biphasic reaction system to efficiently convert styrene into ( S )-styrene oxide with 99% ee in the presence of 2-propanol as a hydrogen donor. The product concentration of the reaction in the organic solvent reached 235 mM after 30 h under optimum conditions. Thus, we demonstrated that this novel shuttle vector is useful for developing biocatalysts based on organic solvent-tolerant Kocuria cells.

Can Ingestion of Lead Shot and Poisons Change Population Trends of Three European Birds: Grey Partridge, Common Buzzard, and Red Kite?

PubMed

Meyer, Carolyn B; Meyer, Joseph S; Francisco, Alex B; Holder, Jennifer; Verdonck, Frederik

2016-01-01

Little is known about the magnitude of the effects of lead shot ingestion alone or combined with poisons (e.g., in bait or seeds/granules containing pesticides) on population size, growth, and extinction of non-waterbird avian species that ingest these substances. We used population models to create example scenarios demonstrating how changes in these parameters might affect three susceptible species: grey partridge (Perdix perdix), common buzzard (Buteo buteo), and red kite (Milvus milvus). We added or subtracted estimates of mortality due to lead shot ingestion (4-16% of mortality, depending on species) and poisons (4-46% of mortality) reported in the UK or France to observed mortality of studied populations after models were calibrated to observed population trends. Observed trends were decreasing for partridge (in continental Europe), stable for buzzard (in Germany), and increasing for red kite (in Wales). Although lead shot ingestion and poison at modeled levels did not change the trend direction for the three species, they reduced population size and slowed population growth. Lead shot ingestion at modeled rates reduced population size of partridges by 10%, and when combined with bait and pesticide poisons, by 18%. For buzzards, decrease in mean population size by lead shot and poisons combined was much smaller (≤ 1%). The red kite population has been recovering; however, modeled lead shot ingestion reduced its annual growth rate from 6.5% to 4%, slowing recovery. If mortality from poisoned baits could be removed, the kite population could potentially increase at a rapid annual rate of 12%. The effects are somewhat higher if ingestion of these substances additionally causes sublethal reproductive impairment. These results have uncertainty but suggest that declining or recovering populations are most sensitive to lead shot or poison ingestion, and removal of poisoned baits can have a positive impact on recovering raptor populations that frequently feed on carrion.

First Solar Power Sail Demonstration by IKAROS

NASA Astrophysics Data System (ADS)

Mori, Osamu; Sawada, Hirotaka; Funase, Ryu; Morimoto, Mutsuko; Endo, Tatsuya; Yamamoto, Takayuki; Tsuda, Yuichi; Kawakatsu, Yasuhiro; Kawaguchi, Jun'ichiro; Miyazaki, Yasuyuki; Shirasawa, Yoji; Demonstration Team; Solar Sail Working Group, Ikaros

The Japan Aerospace Exploration Agency (JAXA) will make the world's first solar power sail craft demonstration of photon propulsion and thin film solar power generation during its interplanetary cruise by IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun). The spacecraft deploys and spans a membrane of 20 meters in diameter taking the advantage of the spin centrifugal force. The spacecraft weighs approximately 310kg, launched together with the agency's Venus Climate Orbiter, AKATSUKI in May 2010. This will be the first actual solar sail flying an interplanetary voyage.

The Kilauea 1974 Flow: Quantitative Morphometry of Lava Flows using Low Altitude Aerial Image Data using a Kite-based Platform in the Field

NASA Astrophysics Data System (ADS)

Scheidt, S. P.; Whelley, P.; Hamilton, C.; Bleacher, J. E.; Garry, W. B.

2015-12-01

The December 31, 1974 lava flow from Kilauea Caldera, Hawaii within the Hawaii Volcanoes National Park was selected for field campaigns as a terrestrial analog for Mars in support of NASA Planetary Geology and Geophysics (PGG) research and the Remote, In Situ and Synchrotron Studies for Science and Exploration (RIS4E) node of the Solar System Exploration Research Virtual Institute (SSERVI) program). The lava flow was a rapidly emplaced unit that was strongly influenced by existing topography, which favored the formation of a tributary lava flow system. The unit includes a diverse range of surface textures (e.g., pāhoehoe, ´áā, and transitional lavas), and structural features (e.g., streamlined islands, pits, and interactions with older tumuli). However, these features are generally below the threshold of visibility within previously acquired airborne and spacecraft data. In this study, we have generated unique, high-resolution digital images using low-altitude Kite Aerial Photography (KAP) system during field campaigns in 2014 and 2015 (National Park Service permit #HAVO-2012-SCI-0025). The kite-based mapping platform (nadir-viewing) and a radio-controlled gimbal (allowing pointing) provided similar data as from an unmanned aerial vehicle (UAV), but with longer flight time, larger total data volumes per sortie, and fewer regulatory challenges and cost. Images acquired from KAP and UAVs are used to create orthomosaics and DEMs using Multi-View Stereo-Photogrammetry (MVSP) software. The 3-Dimensional point clouds are extremely dense, resulting in a grid resolution of < 2 cm. Airborne Light Detection and Ranging (LiDAR) / Terrestrial Laser Scanning (TLS) data have been collected for these areas and provide a basis of comparison or "ground truth" for the photogrammetric data. Our results show a good comparison with LiDAR/TLS data, each offering their own unique advantages and potential for data fusion.

Detecting population-environmental interactions with mismatched time series data.

PubMed

Ferguson, Jake M; Reichert, Brian E; Fletcher, Robert J; Jager, Henriëtte I

2017-11-01

Time series analysis is an essential method for decomposing the influences of density and exogenous factors such as weather and climate on population regulation. However, there has been little work focused on understanding how well commonly collected data can reconstruct the effects of environmental factors on population dynamics. We show that, analogous to similar scale issues in spatial data analysis, coarsely sampled temporal data can fail to detect covariate effects when interactions occur on timescales that are fast relative to the survey period. We propose a method for modeling mismatched time series data that couples high-resolution environmental data to low-resolution abundance data. We illustrate our approach with simulations and by applying it to Florida's southern Snail kite population. Our simulation results show that our method can reliably detect linear environmental effects and that detecting nonlinear effects requires high-resolution covariate data even when the population turnover rate is slow. In the Snail kite analysis, our approach performed among the best in a suite of previously used environmental covariates explaining Snail kite dynamics and was able to detect a potential phenological shift in the environmental dependence of Snail kites. Our work provides a statistical framework for reliably detecting population-environment interactions from coarsely surveyed time series. An important implication of this work is that the low predictability of animal population growth by weather variables found in previous studies may be due, in part, to how these data are utilized as covariates. © 2017 by the Ecological Society of America.

Detecting population–environmental interactions with mismatched time series data

PubMed Central

Ferguson, Jake M.; Reichert, Brian E.; Fletcher, Robert J.; Jager, Henriëtte I.

2017-01-01

Time series analysis is an essential method for decomposing the influences of density and exogenous factors such as weather and climate on population regulation. However, there has been little work focused on understanding how well commonly collected data can reconstruct the effects of environmental factors on population dynamics. We show that, analogous to similar scale issues in spatial data analysis, coarsely sampled temporal data can fail to detect covariate effects when interactions occur on timescales that are fast relative to the survey period. We propose a method for modeling mismatched time series data that couples high-resolution environmental data to low-resolution abundance data. We illustrate our approach with simulations and by applying it to Florida’s southern Snail kite population. Our simulation results show that our method can reliably detect linear environmental effects and that detecting nonlinear effects requires high-resolution covariate data even when the population turnover rate is slow. In the Snail kite analysis, our approach performed among the best in a suite of previously used environmental covariates explaining Snail kite dynamics and was able to detect a potential phenological shift in the environmental dependence of Snail kites. Our work provides a statistical framework for reliably detecting population–environment interactions from coarsely surveyed time series. An important implication of this work is that the low predictability of animal population growth by weather variables found in previous studies may be due, in part, to how these data are utilized as covariates. PMID:28759123

Winter habitat associations of diurnal raptors in Californias Central Valley

USGS Publications Warehouse

Pandolrno, E.R.; Herzog, M.P.; Hooper, S.L.; Smith, Z.

2011-01-01

The wintering raptors of California's Central Valley are abundant and diverse. Despite this, little information exists on the habitats used by these birds in winter. We recorded diurnal raptors along 19 roadside survey routes throughout the Central Valley for three consecutive winters between 2007 and 2010. We obtained data sufficient to determine significant positive and negative habitat associations for the White-tailed Kite (Elanus leucurus), Bald Eagle {Haliaeetus leucocephalus), Northern Harrier (Circus cyaneus), Red-tailed Hawk (Buteo jamaicensis), Ferruginous Hawk (Buteo regalis), Rough-legged Hawk (Buteo lagopus), American Kestrel (Falco sparverius), and Prairie Falcon (Falco mexicanus). The Prairie Falcon and Ferruginous and Rough-legged hawks showed expected strong positive associations with grasslands. The Bald Eagle and Northern Harrier were positively associated not only with wetlands but also with rice. The strongest positive association for the White-tailed Kite was with wetlands. The Red-tailed Hawk was positively associated with a variety of habitat types but most strongly with wetlands and rice. The American Kestrel, Northern Harrier, and White-tailed Kite were positively associated with alfalfa. Nearly all species were negatively associated with urbanized landscapes, orchards, and other intensive forms of agriculture. The White-tailed Kite, Northern Harrier, Redtailed Hawk, Ferruginous Hawk, and American Kestrel showed significant negative associations with oak savanna. Given the rapid conversion of the Central Valley to urban and intensive agricultural uses over the past few decades, these results have important implications for conservation of these wintering raptors in this region.

Hang Gliders

NASA Technical Reports Server (NTRS)

1981-01-01

Francis M. Rogallo and his wife Gertrude researched flexible controllable fabric airfoils with a delta, V-shaped, configuration for use on inexpensive private aircraft. They were issued a flex-wing patent and refined their designs. Development of Rogallo wings, used by U.S. Moyes, Inc. substantially broadened the flexible airfoil technology base which originated from NASA's reentry parachute. The Rogallo technology, particularly the airfoil frame was incorporated in the design of a kite by John Dickenson. The Dickenson kite served as prototype for the Australian Moyes line of hang gliders. Company no longer exists.

Using kites for 3-D mapping of gullies at decimetre-resolution over several square kilometres: a case study on the Kamech catchment, Tunisia

NASA Astrophysics Data System (ADS)

Feurer, Denis; Planchon, Olivier; Amine El Maaoui, Mohamed; Ben Slimane, Abir; Rached Boussema, Mohamed; Pierrot-Deseilligny, Marc; Raclot, Damien

2018-06-01

Monitoring agricultural areas threatened by soil erosion often requires decimetre topographic information over areas of several square kilometres. Airborne lidar and remotely piloted aircraft system (RPAS) imagery have the ability to provide repeated decimetre-resolution and -accuracy digital elevation models (DEMs) covering these extents, which is unrealistic with ground surveys. However, various factors hamper the dissemination of these technologies in a wide range of situations, including local regulations for RPAS and the cost for airborne laser systems and medium-format RPAS imagery. The goal of this study is to investigate the ability of low-tech kite aerial photography to obtain DEMs with decimetre resolution and accuracy that permit 3-D descriptions of active gullying in cultivated areas of several square kilometres. To this end, we developed and assessed a two-step workflow. First, we used both heuristic experimental approaches in field and numerical simulations to determine the conditions that make a photogrammetric flight possible and effective over several square kilometres with a kite and a consumer-grade camera. Second, we mapped and characterised the entire gully system of a test catchment in 3-D. We showed numerically and experimentally that using a thin and light line for the kite is key for a complete 3-D coverage over several square kilometres. We thus obtained a decimetre-resolution DEM covering 3.18 km2 with a mean error and standard deviation of the error of +7 and 22 cm respectively, hence achieving decimetre accuracy. With this data set, we showed that high-resolution topographic data permit both the detection and characterisation of an entire gully system with a high level of detail and an overall accuracy of 74 % compared to an independent field survey. Kite aerial photography with simple but appropriate equipment is hence an alternative tool that has been proven to be valuable for surveying gullies with sub-metric details in a square-kilometre-scale catchment. This case study suggests that access to high-resolution topographic data on these scales can be given to the community, which may help facilitate a better understanding of gullying processes within a broader spectrum of conditions.

High-resolution combined global gravity field modelling: Solving large kite systems using distributed computational algorithms

NASA Astrophysics Data System (ADS)

Zingerle, Philipp; Fecher, Thomas; Pail, Roland; Gruber, Thomas

2016-04-01

One of the major obstacles in modern global gravity field modelling is the seamless combination of lower degree inhomogeneous gravity field observations (e.g. data from satellite missions) with (very) high degree homogeneous information (e.g. gridded and reduced gravity anomalies, beyond d/o 1000). Actual approaches mostly combine such data only on the basis of the coefficients, meaning that previously for both observation classes (resp. models) a spherical harmonic analysis is done independently, solving dense normal equations (NEQ) for the inhomogeneous model and block-diagonal NEQs for the homogeneous. Obviously those methods are unable to identify or eliminate effects as spectral leakage due to band limitations of the models and non-orthogonality of the spherical harmonic base functions. To antagonize such problems a combination of both models on NEQ-basis is desirable. Theoretically this can be achieved using NEQ-stacking. Because of the higher maximum degree of the homogeneous model a reordering of the coefficient is needed which leads inevitably to the destruction of the block diagonal structure of the appropriate NEQ-matrix and therefore also to the destruction of simple sparsity. Hence, a special coefficient ordering is needed to create some new favorable sparsity pattern leading to a later efficient computational solving method. Such pattern can be found in the so called kite-structure (Bosch, 1993), achieving when applying the kite-ordering to the stacked NEQ-matrix. In a first step it is shown what is needed to attain the kite-(NEQ)system, how to solve it efficiently and also how to calculate the appropriate variance information from it. Further, because of the massive computational workload when operating on large kite-systems (theoretically possible up to about max. d/o 100.000), the main emphasis is put on to the presentation of special distributed algorithms which may solve those systems parallel on an indeterminate number of processes and are therefore suitable for the application on supercomputers (such as SuperMUC). Finally, (if time or space) some in-detail problems are shown that occur when dealing with high degree spherical harmonic base functions (mostly due to instabilities of Legendre polynomials), introducing also an appropriate solution for each.

Development of a Novel Escherichia coli–Kocuria Shuttle Vector Using the Cryptic pKPAL3 Plasmid from K. palustris IPUFS-1 and Its Utilization in Producing Enantiopure (S)-Styrene Oxide

PubMed Central

Toda, Hiroshi; Itoh, Nobuya

2017-01-01

The novel cryptic pKPAL3 plasmid was isolated from the Gram-positive microorganism Kocuria palustris IPUFS-1 and characterized in detail. pKPAL3 is a circular plasmid that is 4,443 bp in length. Open reading frame (ORF) and homology search analyses indicated that pKPAL3 possesses four ORFs; however, there were no replication protein coding genes predicted in the plasmid. Instead, there were two nucleotide sequence regions that showed significant identities with untranslated regions of K. rhizophila DC2201 (NBRC 103217) genomic sequences, and these sequences were essential for autonomous replication of pKPAL3 in Kocuria cells. Based on these findings, we constructed the novel Escherichia coli–Kocuria shuttle vectors pKITE301 (kanamycin resistant) and pKITE303 (thiostrepton resistant) from pKPAL3. The copy numbers of the constructed shuttle vectors were estimated to be 20 per cell, and they exhibited low segregation stability in Kocuria transformant cells in the absence of antibiotics. Moreover, constructed vectors showed compatibility with the other K. rhizophila shuttle vector pKITE103. We successfully expressed multiple heterologous genes, including the styrene monooxygenase gene from Rhodococcus sp. ST-10 (rhsmo) and alcohol dehydrogenase gene from Leifsonia sp. S749 (lsadh), in K. rhizophila DC2201 using the pKITE301P and pKITE103P vectors under the control of the glyceraldehyde 3-phosphate dehydrogenase (gapdh) promotor. The RhSMO–LSADH co-expressing K. rhizophila was used as a biocatalyst in an organic solvent–water biphasic reaction system to efficiently convert styrene into (S)-styrene oxide with 99% ee in the presence of 2-propanol as a hydrogen donor. The product concentration of the reaction in the organic solvent reached 235 mM after 30 h under optimum conditions. Thus, we demonstrated that this novel shuttle vector is useful for developing biocatalysts based on organic solvent-tolerant Kocuria cells. PMID:29230202

[Repairing severe cicatricial contracture deformity in web-space by kite-like incision combined with full-thickness skin grafting].

PubMed

Liang, Liming; Chai, Jiake; Jia, Xiaoming; Wang, Yirong; Meng, Suyu; Liu, Tao

2012-12-01

To investigate the effectiveness of repairing severe cicatricial contracture deformity in the web-space by kite-like incision combined with full-thickness skin grafting. Between June 2008 and September 2011, 31 patients (87 web-spaces) with severe cicatricial contracture deformities in the web-spaces were treated. There were 24 males and 7 females, aged 5-43 years (median, 22 years). The causes of injuries were flame burn (26 cases), scald (3 cases), electric arc burn (1 case), and chemical burn (1 case). The degree of burn was deep second degree (14 cases) and third degree (17 cases). The interval time from injury to operation was 10 months to 17 years (median, 2.2 years). The kite-like incision was marked on the scar in the web-space. The rhombic scar between the adjacent metacarpophalangeal joints was excised, and cicatricial contracture was released completely. The secondary wound in the web-space was repaired with full-thickness autogeneic skin grafting. The secondary wound at donor site was directly sutured. All full-thickness skin grafts survived well. The incisions at donor sites healed primarily. Of 31 patients, 29 (82 web-spaces) were followed up 6-18 months (mean, 13 months). The sizes and depths of reconstructed web-spaces were similar to those of normal ones. No secondary cicatricial contracture was observed, and the function of fingers recovered well. The short-term effectiveness is satisfactory by kite-like incision combined with full-thickness skin grafting for repairing severe cicatricial contracture deformities in the web-space, while the long-term effectiveness needs further observation.

Visual abilities in two raptors with different ecology.

PubMed

Potier, Simon; Bonadonna, Francesco; Kelber, Almut; Martin, Graham R; Isard, Pierre-François; Dulaurent, Thomas; Duriez, Olivier

2016-09-01

Differences in visual capabilities are known to reflect differences in foraging behaviour even among closely related species. Among birds, the foraging of diurnal raptors is assumed to be guided mainly by vision but their foraging tactics include both scavenging upon immobile prey and the aerial pursuit of highly mobile prey. We studied how visual capabilities differ between two diurnal raptor species of similar size: Harris's hawks, Parabuteo unicinctus, which take mobile prey, and black kites, Milvus migrans, which are primarily carrion eaters. We measured visual acuity, foveal characteristics and visual fields in both species. Visual acuity was determined using a behavioural training technique; foveal characteristics were determined using ultra-high resolution spectral-domain optical coherence tomography (OCT); and visual field parameters were determined using an ophthalmoscopic reflex technique. We found that these two raptors differ in their visual capacities. Harris's hawks have a visual acuity slightly higher than that of black kites. Among the five Harris's hawks tested, individuals with higher estimated visual acuity made more horizontal head movements before making a decision. This may reflect an increase in the use of monocular vision. Harris's hawks have two foveas (one central and one temporal), while black kites have only one central fovea and a temporal area. Black kites have a wider visual field than Harris's hawks. This may facilitate the detection of conspecifics when they are scavenging. These differences in the visual capabilities of these two raptors may reflect differences in the perceptual demands of their foraging behaviours. © 2016. Published by The Company of Biologists Ltd.

Extreme weather and experience influence reproduction in an endangered bird

USGS Publications Warehouse

Reichert, Brian E.; Cattau, Christopher E.; Fletcher, Robert J.; Kendall, William L.; Kitchens, Wiley M.

2012-01-01

Using a 14-year time series spanning large variation in climatic conditions and the entirety of a population's breeding range, we estimated the effects of extreme weather conditions (drought) on the state-specific probabilities of breeding and survival of an endangered bird, the Florida Snail Kite (Rostrhamus sociabilis plumbeus). Our analysis accounted for uncertainty in breeding status assignment, a common source of uncertainty that is often ignored when states are based on field observations. Breeding probabilities in adult kites (>1 year of age) decreased during droughts, whereas the probability of breeding in young kites (1 year of age) tended to increase. Individuals attempting to breed showed no evidence of reduced future survival. Although population viability analyses of this species and other species often implicitly assume that all adults will attempt to breed, we find that breeding probabilities were significantly <1 for all 13 estimable years considered. Our results suggest that experience is an important factor determining whether or not individuals attempt to breed during harsh environmental conditions and that reproductive effort may be constrained by an individual's quality and/or despotic behavior among individuals attempting to breed.

The kick with the kite: an analysis of kite surfing related off shore rescue missions in Cape Town, South Africa

PubMed Central

Exadaktylos, A; Sclabas, G; Blake, I; Swemmer, K; McCormick, G; Erasmus, P; Muhm, M; Curatolo, M

2005-01-01

Methods: The observation period for this study started on October 1, 2003 and ended on May 1, 2004 and included 30 air rescue missions. Data and information were collected prospectively. Results: The Air Mercy Service in Cape Town Province responded to 30 requests for help. Twenty five accidents were attributed to inability to detach the kite from the harness. Injuries occurred in five incidents and included fractures of the upper arm, ribs and ankle, and lacerations and contusions to the head and neck. Two patients suffered from hypothermia and one experienced severe exhaustion. All surfers were rescued successfully and there were no fatal accidents. Discussion: The risk potential of this new sport is unclear. Dangerous situations can occur despite proper training and safety precautions due to unpredictable conditions and difficulties with equipment. Safety should be stressed. Surfers should sailing with a fellow kiter and should wear a life vest. More efforts must be taken to make this booming new water sport safer. PMID:15849279

Status of the everglade kite in Florida--1968-1978

USGS Publications Warehouse

Sykes, P.W.

1979-01-01

The population status of the Everglade Kite (Rostrhamus sociabils plumbeus) was studied in Florida from 1968 through 1978. Sixty-four nestlings (40% of known fledged young) were leg-banded with unique color combinations, and of these, 17.2% were seen 1 or more years after they were banded. Kites were capable of breeding at 3 years of age or possibly younger. The population was nomadic; its sex ratio unknown. From 1968 through 1976 breeding success was determined for 175 nests, of which 48% were successful: 161 young were fledged, x = 20.1 per year, or 1.9 per successful nest (N = 84). The percentage of successful nests ranged from 17.1 (N = 35) in 1974 to 84.6 (N = 13) in 1968 (x= 54.1 per year). From 1968 through 1976 there was a significant increase (r = 0.685, P < 0.05) in the number of nests ohserved (excluding 1971, and reproduction was not studied in 1977 and 1978). The mortality rate for young in the nest was 41%. Some individuals live for at least 8+ years. The mean number of kites for 10 annual censuses was 120.2 with a range of 65 (1972) to 267 (1978). The severe drought of 1971 resulted in a significant decrease in the population for that year and 1972, with no nesting attempts being observed in the dry year. From 1974 through 1978 the population increased significantly (r = 0.92, P < 0.025), apparently the result of favorable water conditions and increased food supply. The loss of suitable habitat is the major problem facing the species in Florida. A high water level is essential, as this affects food supply and its availability, as well as nesting success.

Spatio-temporal variation in age structure and abundance of the endangered snail kite: Pooling across regions masks a declining and aging population

USGS Publications Warehouse

Reichert, Brian E.; Kendall, William L.; Fletcher, Robert J.; Kitchens, Wiley M.

2016-01-01

While variation in age structure over time and space has long been considered important for population dynamics and conservation, reliable estimates of such spatio-temporal variation in age structure have been elusive for wild vertebrate populations. This limitation has arisen because of problems of imperfect detection, the potential for temporary emigration impacting assessments of age structure, and limited information on age. However, identifying patterns in age structure is important for making reliable predictions of both short- and long-term dynamics of populations of conservation concern. Using a multistate superpopulation estimator, we estimated region-specific abundance and age structure (the proportion of individuals within each age class) of a highly endangered population of snail kites for two separate regions in Florida over 17 years (1997–2013). We find that in the southern region of the snail kite—a region known to be critical for the long-term persistence of the species—the population has declined significantly since 1997, and during this time, it has increasingly become dominated by older snail kites (> 12 years old). In contrast, in the northern region—a region historically thought to serve primarily as drought refugia—the population has increased significantly since 2007 and age structure is more evenly distributed among age classes. Given that snail kites show senescence at approximately 13 years of age, where individuals suffer higher mortality rates and lower breeding rates, these results reveal an alarming trend for the southern region. Our work illustrates the importance of accounting for spatial structure when assessing changes in abundance and age distribution and the need for monitoring of age structure in imperiled species.

Effects of natal departure and water level on survival of juvenile snail kites (Rostrhamus sociabilis) in Florida

USGS Publications Warehouse

Dreitz, V.J.; Kitchens, W.M.; DeAngelis, D.L.

2004-01-01

Survival rate from fledging to breeding, or juvenile survival, is an important source of variation in lifetime reproductive success in birds. Therefore, determining the relationship between juvenile survival and environmental factors is essential to understanding fitness consequences of reproduction in many populations. With increases in density of individuals and depletion of food resources, quality of most habitats deteriorates during the breeding season. Individuals respond by dispersing in search of food resources. Therefore, to understand the influence of environmental factors on juvenile survival, it is also necessary to know how natal dispersal influences survival of juveniles. We examined effects of various environmental factors and natal dispersal behavior on juvenile survival of endangered Snail Kites (Rostrhamus sociabilis) in central and southern Florida, using a generalized estimating equations (GEEs) approach and model selection criteria. Our results suggested yearly effects and an influence of age and monthly minimum hydrologic levels on juvenile Snail Kite survival. Yearly variation in juvenile survival has been reported by other studies, and other reproductive components of Snail Kites also exhibit such variation. Age differences in juvenile survival have also been seen in other species during the juvenile period. Our results demonstrate a positive relationship between water levels and juvenile survival. We suggest that this is not a direct linear relationship, such that higher water means higher juvenile survival. The juvenile period is concurrent with onset of the wet season in the ecosystem we studied, and rainfall increases as juveniles age. For management purposes, we believe that inferences suggesting increasing water levels during the fledging period will increase juvenile survival may have short-term benefits but lead to long-term declines in prey abundance and possibly wetland vegetation structure.

Monitoring agricultural rodenticide use and secondary exposure of raptors in Scotland.

PubMed

Hughes, J; Sharp, E; Taylor, M J; Melton, L; Hartley, G

2013-08-01

Despite the documented risk of secondary poisoning to non-target species by anticoagulant rodenticides there is no statutory post-approval monitoring of their use in the UK. This paper presents results from two Scottish monitoring schemes for the period 2000-2010; recording rodenticide use on arable farms and the presence of residues in raptor carcasses. More than three quarters of arable farms used anticoagulant rodenticides; predominately the second generation compounds difenacoum and bromadiolone. There was widespread exposure to anticoagulant rodenticides in liver tissues of the raptor species tested and the residues encountered generally reflected agricultural use patterns. As found in other studies, Red Kites (Milvus milvus) appeared to be particularly vulnerable to rodenticide exposure, 70 % of those sampled (n = 114) contained residues and 10 % died as a result of rodenticide ingestion. More unexpectedly, sparrowhawks (Accipiter nisus), which prey almost exclusively on birds, had similar exposure rates to species which prey on rodents. Although, with the exception of kites, confirmed mortality from rodenticides was low, the widespread exposure recorded is concerning. Particularly when coupled with a lack of data about the sub-lethal effects of these compounds. This raises questions regarding whether statutory monitoring of use is needed; both to address whether there are deficiencies in compliance with approval conditions or whether the recommended risk management procedures are themselves adequate to protect non-target wildlife.

Sitnikov problem in the cyclic kite configuration

NASA Astrophysics Data System (ADS)

Shahbaz Ullah, M.; Bhatnagar, K. B.; Hassan, M. R.

2014-12-01

This manuscript deals with the development of the series solutions of the Sitnikov kite configuration by the methods given of Lindstedt-Poincarė, using Green's function and MacMillan. Next we have developed averaged equation of motion by applying the Van der Pol transformation and averaging technique of Guckenheimer and Holmes (Nonlinear oscillations, dynamical system bifurcations of vector fields. Springer, Berlin, 1983). In addition to the resonance criterion at the 3/2 commensurability we have chosen ω=2 n/3, n=2, ω is the angular velocity of the coordinate system. Lastly the periodicity of the solutions has been examined by the Poincarė section.

Bothrigaster variolaris (Trematoda: Cyclocoelidae) infection in two Florida snail kites (Rostrhamus sociabilis plumbeus)

USGS Publications Warehouse

Cole, Rebecca A.; Thomas, Nancy J.; Roderick, Constance L.

1995-01-01

Two Florida snail kites (Rostrhamus sociabilis plumbeus, Say) collected in August and December 1993 from Osceola County (28 degrees 15'N, 81 degrees 17'W) and Glades County (26 degrees 45'N, 81 degrees 10'W), Florida (USA), respectively, were infected with Bothrigaster variolaris (Trematoda: Cyclocoelidae); this parasite has not been reported previously from birds in the United States. One bird, a fledgling female, harbored 270 specimens of B. variolaris; the helminths caused airsacculitis and bronchitis, possible contributing factors in the death of this bird. The other bird, a subadult female, was infected with 40 trematodes and had gross and microscopic lesions consistent with trauma as the cause of death.

Picometer Level Modeling of a Shared Vertex Double Corner Cube in the Space Interferometry Mission Kite Testbed

NASA Technical Reports Server (NTRS)

Kuan, Gary M.; Dekens, Frank G.

2006-01-01

The Space Interferometry Mission (SIM) is a microarcsecond interferometric space telescope that requires picometer level precision measurements of its truss and interferometer baselines. Single-gauge metrology errors due to non-ideal physical characteristics of corner cubes reduce the angular measurement capability of the science instrument. Specifically, the non-common vertex error (NCVE) of a shared vertex, double corner cube introduces micrometer level single-gauge errors in addition to errors due to dihedral angles and reflection phase shifts. A modified SIM Kite Testbed containing an articulating double corner cube is modeled and the results are compared to the experimental testbed data. The results confirm modeling capability and viability of calibration techniques.

The use of resighting data to estimate the rate of population growth of the snail kite in Florida

USGS Publications Warehouse

Dreitz, V.J.; Nichols, J.D.; Hines, J.E.; Bennetts, R.E.; Kitchens, W.M.; DeAngelis, D.L.

2002-01-01

The rate of population growth (lambda) is an important demographic parameter used to assess the viability of a population and to develop management and conservation agendas. We examined the use of resighting data to estimate lambda for the snail kite population in Florida from 1997-2000. The analyses consisted of (1) a robust design approach that derives an estimate of lambda from estimates of population size and (2) the Pradel (1996) temporal symmetry (TSM) approach that directly estimates lambda using an open-population capture-recapture model. Besides resighting data, both approaches required information on the number of unmarked individuals that were sighted during the sampling periods. The point estimates of lambda differed between the robust design and TSM approaches, but the 95% confidence intervals overlapped substantially. We believe the differences may be the result of sparse data and do not indicate the inappropriateness of either modelling technique. We focused on the results of the robust design because this approach provided estimates for all study years. Variation among these estimates was smaller than levels of variation among ad hoc estimates based on previously reported index statistics. We recommend that lambda of snail kites be estimated using capture-resighting methods rather than ad hoc counts.

Pesticide concentrations in snail kite eggs and nestlings in Florida

USGS Publications Warehouse

Sykes, P.W.

1985-01-01

From 1970-1977, unhatched snail kite eggs and young that were found dead at nests in Florida were analyzed by gas chromatography for residues of organochlorine pollutants. The 1970 and 1974 material showed measurable amounts of p,p'-DDE, p,p'-DDD, p,p'-DDT, and dieldrin. Dieldrin and polychlorinated biphenyl (PCB) residues were less than 0.1 ppm in the eggs and were detected in only one sample of muscle tissue at 0.11 ppm. Concentrations in ppm wet weight of p,p'-DDE, p,p' DDD, p,p'-DDT, dieldrin, and PCB for two samples of muscle and three of brain tissue (all 1977 material) were not detected at the limit of quantification (0.05 ppm).

Inclusion of pressure and flow in a new 3D MHD equilibrium code

NASA Astrophysics Data System (ADS)

Raburn, Daniel; Fukuyama, Atsushi

2012-10-01

Flow and nonsymmetric effects can play a large role in plasma equilibria and energy confinement. A concept for such a 3D equilibrium code was developed and presented in 2011. The code is called the Kyoto ITerative Equilibrium Solver (KITES) [1], and the concept is based largely on the PIES code [2]. More recently, the work-in-progress KITES code was used to calculate force-free equilibria. Here, progress and results on the inclusion of pressure and flow in the code are presented. [4pt] [1] Daniel Raburn and Atsushi Fukuyama, Plasma and Fusion Research: Regular Articles, 7:240381 (2012).[0pt] [2] H. S. Greenside, A. H. Reiman, and A. Salas, J. Comput. Phys, 81(1):102-136 (1989).

Feasibility study of wind-generated electricity for rural applications in southwestern Ohio

NASA Astrophysics Data System (ADS)

Kohring, G. W.

The parameters associated with domestic production of wind generated electricity for direct use by small farms and rural homes in the southwestern Ohio region are discussed. The project involves direct utility interfaced electricity generation from a horizontal axis, down-wind, fixed pitch, wind powered induction generator system. Goals of the project are to determine: the ability to produce useful amounts of domestic wind generated electricity in the southwestern Ohio region; economic justification for domestic wind generated electrical production; and the potential of domestic wind generated electricity for reducing dependence on non-renewable energy resources in the southwestern Ohio region.

Power Smoothing and MPPT for Grid-connected Wind Power Generation with Doubly Fed Induction Generator

NASA Astrophysics Data System (ADS)

Kai, Takaaki; Tanaka, Yuji; Kaneda, Hirotoshi; Kobayashi, Daichi; Tanaka, Akio

Recently, doubly fed induction generator (DFIG) and synchronous generator are mostly applied for wind power generation, and variable speed control and power factor control are executed for high efficiently for wind energy capture and high quality for power system voltage. In variable speed control, a wind speed or a generator speed is used for maximum power point tracking. However, performances of a wind generation power fluctuation due to wind speed variation have not yet investigated for those controls. The authors discuss power smoothing by those controls for the DFIG inter-connected to 6.6kV distribution line. The performances are verified using power system simulation software PSCAD/EMTDC for actual wind speed data and are examined from an approximate equation of wind generation power fluctuation for wind speed variation.

Photoelectron spectroscopy and density functional theory study of TiAlO(y) (-) (y=1-3) and TiAl(2)O(y) (-) (y=2-3) clusters.

PubMed

Zhang, Zeng-Guang; Xu, Hong-Guang; Zhao, Yuchao; Zheng, Weijun

2010-10-21

Small titanium-aluminum oxide clusters, TiAlO(y) (-) (y=1-3) and TiAl(2)O(y) (-) (y=2-3), were studied by using anion photoelectron spectroscopy. The adiabatic detachment energies of TiAlO(y) (-) (y=1-3) were estimated to be 1.11±0.05, 1.70±0.08, and 2.47±0.08eV based on their photoelectron spectra; those of TiAl(2)O(2) (-) and TiAl(2)O(3) (-) were estimated to be 1.17±0.08 and 2.2±0.1eV, respectively. The structures of these clusters were determined by comparison of density functional calculations with the experimental results. The structure of TiAlO(-) is nearly linear with the O atom in the middle. That of TiAlO(2) (-) is a kite-shaped structure. TiAlO(3) (-) has a kite-shaped TiAlO(2) unit with the third O atom attaching to the Ti atom. TiAl(2)O(2) (-) has two nearly degenerate Al-O-Ti-O-Al chain structures that can be considered as cis and trans forms. TiAl(2)O(3) (-) has two low-lying isomers, kite structure and book structure. The structures of these clusters indicate that the Ti atom tends to bind to more O atoms.

77 FR 22569 - Interconnection of the Grande Prairie Wind Farm, Holt County, NE

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-16

... operations and maintenance building. Grande Prairie Wind would site wind turbine generators and supporting... wind turbines. Permanent disturbance for each wind turbine generator location would be approximately 0.25 acres. Grande Prairie Wind is considering a variety of wind turbine generator types, with...

Methods and apparatus for cooling wind turbine generators

DOEpatents

Salamah, Samir A [Niskayuna, NY; Gadre, Aniruddha Dattatraya [Rexford, NY; Garg, Jivtesh [Schenectady, NY; Bagepalli, Bharat Sampathkumaran [Niskayuna, NY; Jansen, Patrick Lee [Alplaus, NY; Carl, Jr., Ralph James

2008-10-28

A wind turbine generator includes a stator having a core and a plurality of stator windings circumferentially spaced about a generator longitudinal axis. A rotor is rotatable about the generator longitudinal axis, and the rotor includes a plurality of magnetic elements coupled to the rotor and cooperating with the stator windings. The magnetic elements are configured to generate a magnetic field and the stator windings are configured to interact with the magnetic field to generate a voltage in the stator windings. A heat pipe assembly thermally engaging one of the stator and the rotor to dissipate heat generated in the stator or rotor.

Large eddy simulation of the tidal power plant deep green using the actuator line method

NASA Astrophysics Data System (ADS)

Fredriksson, S. T.; Broström, G.; Jansson, M.; Nilsson, H.; Bergqvist, B.

2017-12-01

Tidal energy has the potential to provide a substantial part of the sustainable electric power generation. The tidal power plant developed by Minesto, called Deep Green, is a novel technology using a ‘flying’ kite with an attached turbine, moving at a speed several times higher than the mean flow. Multiple Deep Green power plants will eventually form arrays, which require knowledge of both flow interactions between individual devices and how the array influences the surrounding environment. The present study uses large eddy simulations (LES) and an actuator line model (ALM) to analyze the oscillating turbulent boundary layer flow in tidal currents without and with a Deep Green power plant. We present the modeling technique and preliminary results so far.

Conservation of the Red Kite Milvus milvus (Aves: Accipitriformes) Is Not Affected by the Establishment of a Broad Hybrid Zone with the Black Kite Milvus migrans migrans in Central Europe

PubMed Central

Matušík, Hynek; Pfeiffer, Thomas; Nachtigall, Winfried; Bizos, Jiří; Šimčíková, Daniela; Literák, Ivan

2016-01-01

Among Accipitriformes sensu stricto, only a few species have been reported to form hybrid zones; these include the red kite Milvus milvus and black kite Milvus migrans migrans. M. milvus is endemic to the western Palearctic and has an estimated total population of 20–24,000 breeding pairs. The species was in decline until the 1970s due to persecution and has declined again since the 1990s due to ingestion of rodenticide-treated baits, illegal poisoning and changes in agricultural practices, particularly in its core range. Whereas F1 M. milvus × M. migr. migrans hybrid offspring have been found, F2 and F3 hybrids have only rarely been reported, with low nesting success rates of F1 hybrids and partial hybrid sterility likely playing a role. Here, we analyzed the mitochondrial (CO1 and CytB) and nuclear (Myc) DNA loci of 184 M. milvus, 124 M. migr. migrans and 3 F1 hybrid individuals collected across central Europe. In agreement with previous studies, we found low heterozygosity in M. milvus regardless of locus. We found that populations of both examined species were characterized by a high gene flow within populations, with all of the major haplotypes distributed across the entire examined area. Few haplotypes displayed statistically significant aggregation in one region over another. We did not find mitochondrial DNA of one species in individuals with the plumage of the other species, except in F1 hybrids, which agrees with Haldane´s Rule. It remains to be investigated by genomic methods whether occasional gene flow occurs through the paternal line, as the examined Myc gene displayed only marginal divergence between M. milvus and M. migr. migrans. The central European population of M. milvus is clearly subject to free intraspecific gene flow, which has direct implications when considering the origin of individuals in M. milvus re-introduction programs. PMID:27463515

Analysis of wind energy generation possibilities with various rotor types at disadvantageous wind condition zones

NASA Astrophysics Data System (ADS)

Bieniek, Andrzej

2017-10-01

The paper describe possibilities of energy generation using various rotor types but especially with multi-blade wind engine operates in the areas with unfavourable wind condition. The paper presents also wind energy conversion estimation results presented based on proposed solution of multi-blade wind turbine of outer diameter of 4 m. Based on the wind distribution histogram from the disadvantage wind condition zones (city of Basel) and taking into account design and estimated operating indexes of the considered wind engine rotor an annual energy generation was estimated. Also theoretical energy generation using various types of wind turbines operates at disadvantage wind conditions zones were estimated and compared. The conducted analysis shows that introduction of multi-blade wind rotor instead of the most popular 3- blades or vertical axis rotors results of about 5% better energy generation. Simultaneously there are energy production also at very disadvantages wind condition at wind speed lower then 4 m s-1. Based on considered construction of multi-blade wind engine the rise of rotor mounting height from 10 to 30 m results with more then 300 % better results in terms of electric energy generation.

14 CFR 101.23 - General operating limitations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.23 General operating limitations. (a) You must operate an amateur rocket in...

14 CFR 101.1 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General... intended to be flown at the end of a rope or cable. (3) Any amateur rocket except aerial firework displays...

14 CFR 101.23 - General operating limitations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.23 General operating limitations. (a) You must operate an amateur rocket in...

14 CFR 101.23 - General operating limitations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.23 General operating limitations. (a) You must operate an amateur rocket in...

14 CFR 101.23 - General operating limitations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.23 General operating limitations. (a) You must operate an amateur rocket in...

14 CFR 101.1 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General... intended to be flown at the end of a rope or cable. (3) Any amateur rocket except aerial firework displays...

14 CFR 101.1 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General... intended to be flown at the end of a rope or cable. (3) Any amateur rocket except aerial firework displays...

14 CFR 101.1 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General... intended to be flown at the end of a rope or cable. (3) Any amateur rocket except aerial firework displays...

14 CFR 101.23 - General operating limitations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.23 General operating limitations. (a) You must operate an amateur rocket in...

14 CFR 101.1 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General... intended to be flown at the end of a rope or cable. (3) Any amateur rocket except aerial firework displays...

ARE660 Wind Generator: Low Wind Speed Technology for Small Turbine Development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robert W. Preus; DOE Project Officer - Keith Bennett

2008-04-23

This project is for the design of a wind turbine that can generate most or all of the net energy required for homes and small businesses in moderately windy areas. The purpose is to expand the current market for residential wind generators by providing cost effective power in a lower wind regime than current technology has made available, as well as reduce noise and improve reliability and safety. Robert W. Preus’ experience designing and/or maintaining residential wind generators of many configurations helped identify the need for an improved experience of safety for the consumer. Current small wind products have unreliablemore » or no method of stopping the wind generator in fault or high wind conditions. Consumers and their neighbors do not want to hear their wind generators. In addition, with current technology, only sites with unusually high wind speeds provide payback times that are acceptable for the on-grid user. Abundant Renewable Energy’s (ARE) basic original concept for the ARE660 was a combination of a stall controlled variable speed small wind generator and automatic fail safe furling for shutdown. The stall control for a small wind generator is not novel, but has not been developed for a variable speed application with a permanent magnet alternator (PMA). The fail safe furling approach for shutdown has not been used to our knowledge.« less

Simulation for Grid Connected Wind Turbines with Fluctuating

NASA Astrophysics Data System (ADS)

Ye, Ying; Fu, Yang; Wei, Shurong

This paper establishes the whole dynamic model of wind turbine generator system which contains the wind speed model and DFIG wind turbines model .A simulation sample based on the mathematical models is built by using MATLAB in this paper. Research are did on the performance characteristics of doubly-fed wind generators (DFIG) which connected to power grid with three-phase ground fault and the disturbance by gust and mixed wind. The capacity of the wind farm is 9MW which consists of doubly-fed wind generators (DFIG). Simulation results demonstrate that the three-phase ground fault occurs on grid side runs less affected on the stability of doubly-fed wind generators. However, as a power source, fluctuations of the wind speed will run a large impact on stability of double-fed wind generators. The results also show that if the two disturbances occur in the meantime, the situation will be very serious.

Wind energy conversion system

DOEpatents

Longrigg, Paul

1987-01-01

The wind energy conversion system includes a wind machine having a propeller connected to a generator of electric power, the propeller rotating the generator in response to force of an incident wind. The generator converts the power of the wind to electric power for use by an electric load. Circuitry for varying the duty factor of the generator output power is connected between the generator and the load to thereby alter a loading of the generator and the propeller by the electric load. Wind speed is sensed electro-optically to provide data of wind speed upwind of the propeller, to thereby permit tip speed ratio circuitry to operate the power control circuitry and thereby optimize the tip speed ratio by varying the loading of the propeller. Accordingly, the efficiency of the wind energy conversion system is maximized.

Doubly fed induction generator wind turbines with fuzzy controller: a survey.

PubMed

Sathiyanarayanan, J S; Kumar, A Senthil

2014-01-01

Wind energy is one of the extraordinary sources of renewable energy due to its clean character and free availability. With the increasing wind power penetration, the wind farms are directly influencing the power systems. The majority of wind farms are using variable speed wind turbines equipped with doubly fed induction generators (DFIG) due to their advantages over other wind turbine generators (WTGs). Therefore, the analysis of wind power dynamics with the DFIG wind turbines has become a very important research issue, especially during transient faults. This paper presents fuzzy logic control of doubly fed induction generator (DFIG) wind turbine in a sample power system. Fuzzy logic controller is applied to rotor side converter for active power control and voltage regulation of wind turbine.

Shape-designed frustration by local polymorphism in a near-equilibrium colloidal glass.

PubMed

Zhao, Kun; Mason, Thomas G

2015-09-29

We show that hard, convex, lithographic, prismatic kite platelets, each having three 72° vertices and one 144° vertex, preferentially form a disordered and arrested 2D glass when concentrated quasi-statically in a monolayer while experiencing thermal Brownian fluctuations. By contrast with 2D systems of other hard convex shapes, such as squares, rhombs, and pentagons, which readily form crystals at high densities, 72° kites retain a liquid-like disordered structure that becomes frozen-in as their long-time translational and rotational diffusion become highly bounded, yielding a 2D colloidal glass. This robust glass-forming propensity arises from competition between highly diverse few-particle local polymorphic configurations (LPCs) that have incommensurate features and symmetries. Thus, entropy maximization is consistent with the preservation of highly diverse LPCs en route to the arrested glass.

Parathion poisoning of Mississippi kites in Oklahoma

USGS Publications Warehouse

Franson, J. Christian

1994-01-01

Parathion(phosphorothioic acid O, O-diethyl O-[4-nitrophenyl] ester) is a broad spectrum organophosphorus insecticide, used on a variety of crops and occasionally for mosquito control, and is highly toxic to birds (Smith 1987). Intentional poisoning with parathion is reported to have killed more than 8000 red-winged blackbirds (Agelaius phoeniceus), common grackles (Quiscalus quiscula), brown-headed cowbirds (Molothrus ater) and European starlings (Sturnus vulgaris) in two separate instances (Stone et al. 1984). Use of parathion on wheat fields has resulted in the mortality of about 1600 Canada geese (Branta canadensis) and other waterfowl in one instance (White et al. 1982) and about 200 Canada geese in another (Flickinger et al. 1991). More than 200 laughing gulls (Larus atricilla) died near cotton fields treated with parathion (White et al. 1979). Secondary poisoning of raptors resulting from the consumption of prey exposed to parathion, has been reported experimentally and in the field. Stone et al. (1984) found two dead red-tailed hawks (Buteo jamaicensis), a Cooper's hawk (Accipiter cooperii) and an American kestrel (Falco sparverius) that had fed on blackbirds killed by parathion. One of four American kestrels died after being fed cricket frogs (Acris crepitans) that had been exposed to 10ppm parathion for 96 hr (Fleming et al. 1982). The Mississippi kite (Ictinia mississippensis) is highly insectivorous (Brown and Amadon 1968) and is thus subject to secondary poisoning resulting from consumption of insects exposed to pesticides. I report here an instance of secondary parathion poisoning in wild Mississippi kites.

Effect of wind turbine generator model and siting on wind power changes out of large WECS arrays

NASA Technical Reports Server (NTRS)

Schleuter, R. A.; Park, G. L.; Lotfalian, M.; Dorsey, J.; Shayanfar, H.

1981-01-01

Methods of reducing the WECS generation change through selection of the wind turbine model for each site, selection of an appropriate siting configuration, and wind array controls are discussed. An analysis of wind generation change from an echelon and a farm for passage of a thunderstorm is presented. Reduction of the wind generation change over ten minutes is shown to reduce the increase in spinning reserve, unloadable generation and load following requirements on unit commitment when significant WECS generation is present and the farm penetration constraint is satisfied. Controls on the blade pitch angle of all wind turbines in an array or a battery control are shown to reduce both the wind generation change out of an array and the effective farm penetration in anticipation of a storm so that the farm penetration constraint may be satisfied.

76 FR 74072 - Endangered and Threatened Wildlife and Plants; Incidental Take Permit Application; Habitat...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-30

... operating the Kaheawa Pastures Wind Energy Generation Facility (KWPI wind farm) for generating electricity... the Kaheawa Pastures Wind Energy Generation Facility (KWPI wind farm) for generating electricity on... generates electricity on Maui. The Service listed the Hawaiian petrel as endangered on March 11, 1967 (32 FR...

An optimal design of coreless direct-drive axial flux permanent magnet generator for wind turbine

NASA Astrophysics Data System (ADS)

Ahmed, D.; Ahmad, A.

2013-06-01

Different types of generators are currently being used in wind power technology. The commonly used are induction generator (IG), doubly-fed induction generator (DFIG), electrically excited synchronous generator (EESG) and permanent magnet synchronous generator (PMSG). However, the use of PMSG is rapidly increasing because of advantages such as higher power density, better controllability and higher reliability. This paper presents an innovative design of a low-speed modular, direct-drive axial flux permanent magnet (AFPM) generator with coreless stator and rotor for a wind turbine power generation system that is developed using mathematical and analytical methods. This innovative design is implemented in MATLAB / Simulink environment using dynamic modelling techniques. The main focus of this research is to improve efficiency of the wind power generation system by investigating electromagnetic and structural features of AFPM generator during its operation in wind turbine. The design is validated by comparing its performance with standard models of existing wind power generators. The comparison results demonstrate that the proposed model for the wind power generator exhibits number of advantages such as improved efficiency with variable speed operation, higher energy yield, lighter weight and better wind power utilization.

Modeling long correlation times using additive binary Markov chains: Applications to wind generation time series.

PubMed

Weber, Juliane; Zachow, Christopher; Witthaut, Dirk

2018-03-01

Wind power generation exhibits a strong temporal variability, which is crucial for system integration in highly renewable power systems. Different methods exist to simulate wind power generation but they often cannot represent the crucial temporal fluctuations properly. We apply the concept of additive binary Markov chains to model a wind generation time series consisting of two states: periods of high and low wind generation. The only input parameter for this model is the empirical autocorrelation function. The two-state model is readily extended to stochastically reproduce the actual generation per period. To evaluate the additive binary Markov chain method, we introduce a coarse model of the electric power system to derive backup and storage needs. We find that the temporal correlations of wind power generation, the backup need as a function of the storage capacity, and the resting time distribution of high and low wind events for different shares of wind generation can be reconstructed.

Modeling long correlation times using additive binary Markov chains: Applications to wind generation time series

NASA Astrophysics Data System (ADS)

Weber, Juliane; Zachow, Christopher; Witthaut, Dirk

2018-03-01

Wind power generation exhibits a strong temporal variability, which is crucial for system integration in highly renewable power systems. Different methods exist to simulate wind power generation but they often cannot represent the crucial temporal fluctuations properly. We apply the concept of additive binary Markov chains to model a wind generation time series consisting of two states: periods of high and low wind generation. The only input parameter for this model is the empirical autocorrelation function. The two-state model is readily extended to stochastically reproduce the actual generation per period. To evaluate the additive binary Markov chain method, we introduce a coarse model of the electric power system to derive backup and storage needs. We find that the temporal correlations of wind power generation, the backup need as a function of the storage capacity, and the resting time distribution of high and low wind events for different shares of wind generation can be reconstructed.

Doubly Fed Induction Generator Wind Turbines with Fuzzy Controller: A Survey

PubMed Central

Sathiyanarayanan, J. S.; Senthil Kumar, A.

2014-01-01

Wind energy is one of the extraordinary sources of renewable energy due to its clean character and free availability. With the increasing wind power penetration, the wind farms are directly influencing the power systems. The majority of wind farms are using variable speed wind turbines equipped with doubly fed induction generators (DFIG) due to their advantages over other wind turbine generators (WTGs). Therefore, the analysis of wind power dynamics with the DFIG wind turbines has become a very important research issue, especially during transient faults. This paper presents fuzzy logic control of doubly fed induction generator (DFIG) wind turbine in a sample power system. Fuzzy logic controller is applied to rotor side converter for active power control and voltage regulation of wind turbine. PMID:25028677

Go Fly a Tetrahedron!

ERIC Educational Resources Information Center

Cowens, John

1995-01-01

Describes a science unit used in a fourth-grade class to teach students about Bernoulli's law of flight, the similarity of tetrahedrons to birds, and the construction of tetrahedron kites. Also includes thought-provoking math questions for students. (MDM)

Plans and status of the NASA-Lewis Research Center wind energy project

NASA Technical Reports Server (NTRS)

Thomas, R.; Puthoff, R.; Savino, J.; Johnson, W.

1975-01-01

Wind energy is investigated as a source of energy. The wind energy program that is managed by the NASA-Lewis Research Center is described. The Lewis Research Center's Wind Power Office, its organization, plans, and status are discussed. Major elements of the wind power project included are: an experimental 100 kW wind-turbine generator; first generation industry-built and user-operated wind turbine generators; and supporting research and technology tasks.

Power Maximization Control of Variable Speed Wind Generation System Using Permanent Magnet Synchronous Generator

NASA Astrophysics Data System (ADS)

Morimoto, Shigeo; Nakamura, Tomohiko; Takeda, Yoji

This paper proposes the sensorless output power maximization control of the wind generation system. A permanent magnet synchronous generator (PMSG) is used as a variable speed generator in the proposed system. The generator torque is suitably controlled according to the generator speed and thus the power from a wind turbine settles down on the maximum power point by the proposed MPPT control method, where the information of wind velocity is not required. Moreover, the maximum available generated power is obtained by the optimum current vector control. The current vector of PMSG is optimally controlled according to the generator speed and the required torque in order to minimize the losses of PMSG considering the voltage and current constraints. The proposed wind power generation system can be achieved without mechanical sensors such as a wind velocity detector and a position sensor. Several experimental results show the effectiveness of the proposed control method.

Engineering handbook on the atmospheric environmental guidelines for use in wind turbine generator development

NASA Technical Reports Server (NTRS)

Frost, W.; Long, B. H.; Turner, R. E.

1978-01-01

The guidelines are given in the form of design criteria relative to wind speed, wind shear, turbulence, wind direction, ice and snow loading, and other climatological parameters which include rain, hail, thermal effects, abrasive and corrosive effects, and humidity. This report is a presentation of design criteria in an engineering format which can be directly input to wind turbine generator design computations. Guidelines are also provided for developing specialized wind turbine generators or for designing wind turbine generators which are to be used in a special region of the United States.

Effect of accuracy of wind power prediction on power system operator

NASA Technical Reports Server (NTRS)

Schlueter, R. A.; Sigari, G.; Costi, T.

1985-01-01

This research project proposed a modified unit commitment that schedules connection and disconnection of generating units in response to load. A modified generation control is also proposed that controls steam units under automatic generation control, fast responding diesels, gas turbines and hydro units under a feedforward control, and wind turbine array output under a closed loop array control. This modified generation control and unit commitment require prediction of trend wind power variation one hour ahead and the prediction of error in this trend wind power prediction one half hour ahead. An improved meter for predicting trend wind speed variation is developed. Methods for accurately simulating the wind array power from a limited number of wind speed prediction records was developed. Finally, two methods for predicting the error in the trend wind power prediction were developed. This research provides a foundation for testing and evaluating the modified unit commitment and generation control that was developed to maintain operating reliability at a greatly reduced overall production cost for utilities with wind generation capacity.

Real-time simulation of a Doubly-Fed Induction Generator based wind power system on eMEGASimRTM Real-Time Digital Simulator

NASA Astrophysics Data System (ADS)

Boakye-Boateng, Nasir Abdulai

The growing demand for wind power integration into the generation mix prompts the need to subject these systems to stringent performance requirements. This study sought to identify the required tools and procedures needed to perform real-time simulation studies of Doubly-Fed Induction Generator (DFIG) based wind generation systems as basis for performing more practical tests of reliability and performance for both grid-connected and islanded wind generation systems. The author focused on developing a platform for wind generation studies and in addition, the author tested the performance of two DFIG models on the platform real-time simulation model; an average SimpowerSystemsRTM DFIG wind turbine, and a detailed DFIG based wind turbine using ARTEMiSRTM components. The platform model implemented here consists of a high voltage transmission system with four integrated wind farm models consisting in total of 65 DFIG based wind turbines and it was developed and tested on OPAL-RT's eMEGASimRTM Real-Time Digital Simulator.

Market protocols in ERCOT and their effect on wind generation

DOE PAGES

Sioshansi, Ramteen; Hurlbut, David

2009-08-22

Integrating wind generation into power systems and wholesale electricity markets presents unique challenges due to the characteristics of wind power, including its limited dispatchability, variability in generation, difficulty in forecasting resource availability, and the geographic location of wind resources. Texas has had to deal with many of these issues beginning in 2002 when it restructured its electricity industry and introduced aggressive renewable portfolio standards that helped spur major investments in wind generation. In this paper we discuss the issues that have arisen in designing market protocols that take account of these special characteristics of wind generation and survey the regulatorymore » and market rules that have been developed in Texas. We discuss the perverse incentives some of the rules gave wind generators to overschedule generation in order to receive balancing energy payments, and steps that have been taken to mitigate those incentive effects. Lastly, we discuss more recent steps taken by the market operator and regulators to ensure transmission capacity is available for new wind generators that are expected to come online in the future.« less

Evaluating the impacts of real-time pricing on the usage of wind generation

DOE PAGES

Sioshansi, Ramteen; Short, Walter

2009-02-13

One of the impediments to large-scale use of wind generation within power systems is its nondispatchability and variable and uncertain real-time availability. Operating constraints on conventional generators such as minimum generation points, forbidden zones, and ramping limits as well as system constraints such as power flow limits and ancillary service requirements may force a system operator to curtail wind generation in order to ensure feasibility. Furthermore, the pattern of wind availability and electricity demand may not allow wind generation to be fully utilized in all hours. One solution to these issues, which could reduce these inflexibilities, is the use ofmore » real-time pricing (RTP) tariffs which can both smooth-out the diurnal load pattern in order to reduce the impact of binding unit operating and system constraints on wind utilization, and allow demand to increase in response to the availability of costless wind generation. As a result, we use and analyze a detailed unit commitment model of the Texas power system with different estimates of demand elasticities to demonstrate the potential increases in wind generation from implementing RTP.« less

Aviation. Teacher Resources.

ERIC Educational Resources Information Center

2001

This teacher's guide contains information, lesson plans, and diverse student learning activities focusing on aviation. The guide is divided into seven sections: (1) "Drawing Activities" (Airmail Art; Eyewitness; Kite Power); (2) "Geography" (U.S. Airports); (3) "Information" (Aviation Alphabet; Glossary; Four Forces…

Infants Can Study Air Science.

ERIC Educational Resources Information Center

Ward, Alan

1983-01-01

Provided are activities and demonstrations which can be used to teach infants about the nature of air, uses of air, and objects that fly in the air. The latter include airships, hot-air balloons, kites, parachutes, airplanes, and Hovercraft. (JN)

Methods and apparatus for rotor load control in wind turbines

DOEpatents

Moroz, Emilian Mieczyslaw

2006-08-22

A wind turbine having a rotor, at least one rotor blade, and a plurality of generators, of which a first generator is configured to provide power to an electric grid and a second generator is configured to provide power to the wind turbine during times of grid loss. The wind turbine is configured to utilize power provided by the second generator to reduce loads on the wind turbine during times of grid loss.

Wind Energy Conference, Boulder, Colo., April 9-11, 1980, Technical Papers

NASA Astrophysics Data System (ADS)

1980-03-01

Papers are presented concerning the technology, and economics of wind energy conversion systems. Specific topics include the aerodynamic analysis of the Darrieus rotor, the numerical calculation of the flow near horizontal-axis wind turbine rotors, the calculation of dynamic wind turbine rotor loads, markets for wind energy systems, an oscillating-wing windmill, wind tunnel tests of wind rotors, wind turbine generator wakes, the application of a multi-speed electrical generator to wind turbines, the feasibility of wind-powered systems for dairy farms, and wind characteristics over uniform and complex terrain. Attention is also given to performance tests of the DOE/NASA MOD-1 2000-kW wind turbine generator, the assessment of utility-related test data, offshore wind energy conversion systems, and the optimization of wind energy utilization economics through load management.

Probability density function characterization for aggregated large-scale wind power based on Weibull mixtures

DOE PAGES

Gomez-Lazaro, Emilio; Bueso, Maria C.; Kessler, Mathieu; ...

2016-02-02

Here, the Weibull probability distribution has been widely applied to characterize wind speeds for wind energy resources. Wind power generation modeling is different, however, due in particular to power curve limitations, wind turbine control methods, and transmission system operation requirements. These differences are even greater for aggregated wind power generation in power systems with high wind penetration. Consequently, models based on one-Weibull component can provide poor characterizations for aggregated wind power generation. With this aim, the present paper focuses on discussing Weibull mixtures to characterize the probability density function (PDF) for aggregated wind power generation. PDFs of wind power datamore » are firstly classified attending to hourly and seasonal patterns. The selection of the number of components in the mixture is analyzed through two well-known different criteria: the Akaike information criterion (AIC) and the Bayesian information criterion (BIC). Finally, the optimal number of Weibull components for maximum likelihood is explored for the defined patterns, including the estimated weight, scale, and shape parameters. Results show that multi-Weibull models are more suitable to characterize aggregated wind power data due to the impact of distributed generation, variety of wind speed values and wind power curtailment.« less

Maximum wind energy extraction strategies using power electronic converters

NASA Astrophysics Data System (ADS)

Wang, Quincy Qing

2003-10-01

This thesis focuses on maximum wind energy extraction strategies for achieving the highest energy output of variable speed wind turbine power generation systems. Power electronic converters and controls provide the basic platform to accomplish the research of this thesis in both hardware and software aspects. In order to send wind energy to a utility grid, a variable speed wind turbine requires a power electronic converter to convert a variable voltage variable frequency source into a fixed voltage fixed frequency supply. Generic single-phase and three-phase converter topologies, converter control methods for wind power generation, as well as the developed direct drive generator, are introduced in the thesis for establishing variable-speed wind energy conversion systems. Variable speed wind power generation system modeling and simulation are essential methods both for understanding the system behavior and for developing advanced system control strategies. Wind generation system components, including wind turbine, 1-phase IGBT inverter, 3-phase IGBT inverter, synchronous generator, and rectifier, are modeled in this thesis using MATLAB/SIMULINK. The simulation results have been verified by a commercial simulation software package, PSIM, and confirmed by field test results. Since the dynamic time constants for these individual models are much different, a creative approach has also been developed in this thesis to combine these models for entire wind power generation system simulation. An advanced maximum wind energy extraction strategy relies not only on proper system hardware design, but also on sophisticated software control algorithms. Based on literature review and computer simulation on wind turbine control algorithms, an intelligent maximum wind energy extraction control algorithm is proposed in this thesis. This algorithm has a unique on-line adaptation and optimization capability, which is able to achieve maximum wind energy conversion efficiency through continuously improving the performance of wind power generation systems. This algorithm is independent of wind power generation system characteristics, and does not need wind speed and turbine speed measurements. Therefore, it can be easily implemented into various wind energy generation systems with different turbine inertia and diverse system hardware environments. In addition to the detailed description of the proposed algorithm, computer simulation results are presented in the thesis to demonstrate the advantage of this algorithm. As a final confirmation of the algorithm feasibility, the algorithm has been implemented inside a single-phase IGBT inverter, and tested with a wind simulator system in research laboratory. Test results were found consistent with the simulation results. (Abstract shortened by UMI.)

A study on the power generation potential of mini wind turbine in east coast of Peninsular Malaysia

NASA Astrophysics Data System (ADS)

Basrawi, Firdaus; Ismail, Izwan; Ibrahim, Thamir Khalil; Idris, Daing Mohamad Nafiz Daing; Anuar, Shahrani

2017-03-01

A small-scale wind turbine is an attractive renewable energy source, but its economic viability depends on wind speed. The aim of this study is to determine economic viability of small-scale wind turbine in East Coast of Peninsular Malaysia. The potential energy generated has been determined by wind speed data and power curved of. Hourly wind speed data of Kuantan throughout 2015 was collected as the input. Then, a model of wind turbine was developed based on a commercial a 300W mini wind turbine. It was found that power generation is 3 times higher during northeast monsoon season at 15 m elevation. This proved that the northeast monsoon season has higher potential in generating power by wind turbine in East Coast of Peninsular Malaysia. However, only a total of 153.4 kWh/year of power can be generated at this condition. The power generator utilization factor PGUI or capacity ratio was merely 0.06 and it is not technically viable. By increasing the height of wind turbine to 60 m elevation, power generation amount drastically increased to 344 kWh/year, with PGUI of 0.13. This is about two-thirds of PGUI for photovoltaic technology which is 0.21 at this site. If offshore condition was considered, power generation amount further increased to 1,328 kWh/year with PGUI of 0.51. Thus, for a common use of mini wind turbine that is usually installed on-site at low elevation, it has low power generation potential. But, if high elevation as what large wind turbine needed is implemented, it is technically viable option in East Coast of Peninsular Malaysia.

Quantifying the Impact of Background Atmospheric Stability on Air-Ice-Ocean Interactions the Arctic Ocean During the Fall Freeze-Up

NASA Astrophysics Data System (ADS)

Guest, P. S.; Persson, O. P. G.; Blomquist, B.; Fairall, C. W.

2016-02-01

"Background" stability refers to the effect of vertical virtual temperature variations above the surface layer on fluxes within the surface layer. This is different from the classical surface layer stability quantified by the Obhukhov length scale. In most locations, changes in the background stability do not have a significant direct impact on surface fluxes. However in polar regions, where there is usually a strong low-level temperature inversion capping the boundary layer, changes in background stability can have big impacts on surface fluxes. Therefore, in the Arctic, there is potential for a positive feedback effect between ice cover and surface wind speed (and momentum flux) due to the background stability effects. As the surface becomes more ice free, heat fluxes from the surface weaken the temperature inversion which in turn increases the surface wind speed which further increases the surface turbulent heat fluxes and removes more sea ice by melting or advection. It is not clear how important feedbacks involving the background stability are during the fall freeze up of the Arctic Ocean; that will be the focus of this study. As part of an ONR-sponsored cruise in the fall of 2015 to examine sea state and boundary layer processes in the Beaufort Sea on the R/V Sikuliaq, the authors will perform a variety of surface layer and upper level atmospheric measurements of temperature, humidity and wind vector using ship platform instruments, radiosonde weather balloons, tethered balloons, kites, and miniature quad-rotor unmanned aerial vehicles. In addition, the authors will deploy a full suite of turbulent and radiational flux measurements from the vessel. These measurements will be used to quantify the impact of changing surface conditions on atmospheric structure and vice-versa. The goal is to directly observe how the surface and atmosphere above the surface layer interact and feedback with each other through radiational and turbulent fluxes.

Three essays on the effect of wind generation on power system planning and operations

NASA Astrophysics Data System (ADS)

Davis, Clay Duane

While the benefits of wind generation are well known, some drawbacks are still being understood as wind power is integrated into the power grid at increasing levels. The primary difference between wind generation and other forms of generation is the intermittent, and somewhat unpredictable, aspect of this resource. The somewhat uncontrollable aspect of wind generation makes it important to consider the relationship between this resource and load, and also how the operation of other non-wind generation resources may be affected. The three essays that comprise this dissertation focus on these and other important issues related to wind generation; leading to an improved understanding of how to better plan for and utilize this resource. The first essay addresses the cost of increased levels of installed wind capacity from both a capacity planning and economic dispatch perspective to arrive at the total system cost of installing a unit of wind capacity. This total includes not only the cost of the wind turbine and associated infrastructure, but also the cost impact an additional unit of wind capacity has on the optimal mix and operation of other generating units in the electricity supply portfolio. The results of the model showed that for all wind expansion scenarios, wind capacity is not cost-effective regardless of the level of the wind production tax credit and carbon prices that were considered. Larger levels of installed wind capacity result in reduced variable cost, but this reduction is not able to offset increases in capital cost, as a unit of installed wind capacity does not result in an equal reduction in other non-wind capacity needs. The second essay develops a methodology to better handle unexpected short term fluctuations in wind generation within the existing power system. The methodology developed in this essay leads to lower expected costs by anticipating and planning for fluctuations in wind generation by focusing on key constraints in the system. The modified methodology achieves expected costs for the UC-ED problem that are as low as the full stochastic model and markedly lower than the deterministic model. The final essay focuses on valuing energy storage located at a wind site through multiple revenue streams, where energy storage is valued from the perspective of a profit maximizing investor. Given the current state of battery storage technology, a battery capacity of zero is optimal in the setting considered in this essay. The results presented in this essay are dependent on a technological breakthrough that substantially reduces battery cost and conclude that allowing battery storage to simultaneously participate in multiple wholesale markets is optimal relative to participating in any one market alone. Also, co-locating battery storage and wind provides value by altering the optimal transmission line capacity to the battery and wind site. This dissertation considers problems of wind integration from an economic perspective and builds on existing work in this area. The economics of wind integration and utilization are important because wind generation levels are already significant and will likely become more so in the future. While this dissertation adds to the existing literature, additional work is needed in this area to ensure wind generation adds as much value to the overall system as possible.

Smart pitch control strategy for wind generation system using doubly fed induction generator

NASA Astrophysics Data System (ADS)

Raza, Syed Ahmed

A smart pitch control strategy for a variable speed doubly fed wind generation system is presented in this thesis. A complete dynamic model of DFIG system is developed. The model consists of the generator, wind turbine, aerodynamic and the converter system. The strategy proposed includes the use of adaptive neural network to generate optimized controller gains for pitch control. This involves the generation of controller parameters of pitch controller making use of differential evolution intelligent technique. Training of the back propagation neural network has been carried out for the development of an adaptive neural network. This tunes the weights of the network according to the system states in a variable wind speed environment. Four cases have been taken to test the pitch controller which includes step and sinusoidal changes in wind speeds. The step change is composed of both step up and step down changes in wind speeds. The last case makes use of scaled wind data collected from the wind turbine installed at King Fahd University beach front. Simulation studies show that the differential evolution based adaptive neural network is capable of generating the appropriate control to deliver the maximum possible aerodynamic power available from wind to the generator in an efficient manner by minimizing the transients.

Neural network based control of Doubly Fed Induction Generator in wind power generation

NASA Astrophysics Data System (ADS)

Barbade, Swati A.; Kasliwal, Prabha

2012-07-01

To complement the other types of pollution-free generation wind energy is a viable option. Previously wind turbines were operated at constant speed. The evolution of technology related to wind systems industry leaded to the development of a generation of variable speed wind turbines that present many advantages compared to the fixed speed wind turbines. In this paper the phasor model of DFIG is used. This paper presents a study of a doubly fed induction generator driven by a wind turbine connected to the grid, and controlled by artificial neural network ANN controller. The behaviour of the system is shown with PI control, and then as controlled by ANN. The effectiveness of the artificial neural network controller is compared to that of a PI controller. The SIMULINK/MATLAB simulation for Doubly Fed Induction Generator and corresponding results and waveforms are displayed.

Careers in Wind Energy

ERIC Educational Resources Information Center

Liming, Drew; Hamilton, James

2011-01-01

As a common form of renewable energy, wind power is generating more than just electricity. It is increasingly generating jobs for workers in many different occupations. Many workers are employed on wind farms: areas where groups of wind turbines produce electricity from wind power. Wind farms are frequently located in the midwestern, western, and…

Analyzing Effects of Turbulence on Power Generation Using Wind Plant Monitoring Data: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, J.; Chowdhury, S.; Hodge, B. M.

2014-01-01

In this paper, a methodology is developed to analyze how ambient and wake turbulence affects the power generation of a single wind turbine within an array of turbines. Using monitoring data from a wind power plant, we selected two sets of wind and power data for turbines on the edge of the wind plant that resemble (i) an out-of-wake scenario (i.e., when the turbine directly faces incoming winds) and (ii) an in-wake scenario (i.e., when the turbine is under the wake of other turbines). For each set of data, two surrogate models were then developed to represent the turbine powermore » generation (i) as a function of the wind speed; and (ii) as a function of the wind speed and turbulence intensity. Support vector regression was adopted for the development of the surrogate models. Three types of uncertainties in the turbine power generation were also investigated: (i) the uncertainty in power generation with respect to the published/reported power curve, (ii) the uncertainty in power generation with respect to the estimated power response that accounts for only mean wind speed; and (iii) the uncertainty in power generation with respect to the estimated power response that accounts for both mean wind speed and turbulence intensity. Results show that (i) under the same wind conditions, the turbine generates different power between the in-wake and out-of-wake scenarios, (ii) a turbine generally produces more power under the in-wake scenario than under the out-of-wake scenario, (iii) the power generation is sensitive to turbulence intensity even when the wind speed is greater than the turbine rated speed, and (iv) there is relatively more uncertainty in the power generation under the in-wake scenario than under the out-of-wake scenario.« less

Wind noise under a pine tree canopy.

PubMed

Raspet, Richard; Webster, Jeremy

2015-02-01

It is well known that infrasonic wind noise levels are lower for arrays placed in forests and under vegetation than for those in open areas. In this research, the wind noise levels, turbulence spectra, and wind velocity profiles are measured in a pine forest. A prediction of the wind noise spectra from the measured meteorological parameters is developed based on recent research on wind noise above a flat plane. The resulting wind noise spectrum is the sum of the low frequency wind noise generated by the turbulence-shear interaction near and above the tops of the trees and higher frequency wind noise generated by the turbulence-turbulence interaction near the ground within the tree layer. The convection velocity of the low frequency wind noise corresponds to the wind speed above the trees while the measurements showed that the wind noise generated by the turbulence-turbulence interaction is near stationary and is generated by the slow moving turbulence adjacent to the ground. Comparison of the predicted wind noise spectrum with the measured wind noise spectrum shows good agreement for four measurement sets. The prediction can be applied to meteorological estimates to predict the wind noise under other pine forests.

Kansas Wind Energy Consortium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gruenbacher, Don

2015-12-31

This project addresses both fundamental and applied research problems that will help with problems defined by the DOE “20% Wind by 2030 Report”. In particular, this work focuses on increasing the capacity of small or community wind generation capabilities that would be operated in a distributed generation approach. A consortium (KWEC – Kansas Wind Energy Consortium) of researchers from Kansas State University and Wichita State University aims to dramatically increase the penetration of wind energy via distributed wind power generation. We believe distributed generation through wind power will play a critical role in the ability to reach and extend themore » renewable energy production targets set by the Department of Energy. KWEC aims to find technical and economic solutions to enable widespread implementation of distributed renewable energy resources that would apply to wind.« less

Flapping wing applied to wind generators

NASA Astrophysics Data System (ADS)

Colidiuc, Alexandra; Galetuse, Stelian; Suatean, Bogdan

2012-11-01

The new conditions at the international level for energy source distributions and the continuous increasing of energy consumption must lead to a new alternative resource with the condition of keeping the environment clean. This paper offers a new approach for a wind generator and is based on the theoretical aerodynamic model. This new model of wind generator helped me to test what influences would be if there will be a bird airfoil instead of a normal wind generator airfoil. The aim is to calculate the efficiency for the new model of wind generator. A representative direction for using the renewable energy is referred to the transformation of wind energy into electrical energy, with the help of wind turbines; the development of such systems lead to new solutions based on high efficiency, reduced costs and suitable to the implementation conditions.

14 CFR 91.1 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Applicability. 91.1 Section 91.1 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC... prescribes rules governing the operation of aircraft (other than moored balloons, kites, unmanned rockets...

14 CFR 91.1 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Applicability. 91.1 Section 91.1 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC... prescribes rules governing the operation of aircraft (other than moored balloons, kites, unmanned rockets...

14 CFR 101.11 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Applicability. 101.11 Section 101.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.11 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Applicability. 101.11 Section 101.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.33 - Operating limitations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Operating limitations. 101.33 Section 101.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.11 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Applicability. 101.11 Section 101.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.31 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Applicability. 101.31 Section 101.31 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.33 - Operating limitations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Operating limitations. 101.33 Section 101.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.31 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Applicability. 101.31 Section 101.31 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.31 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Applicability. 101.31 Section 101.31 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.31 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Applicability. 101.31 Section 101.31 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.13 - Operating limitations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Operating limitations. 101.13 Section 101.13 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.13 - Operating limitations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Operating limitations. 101.13 Section 101.13 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.13 - Operating limitations.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Operating limitations. 101.13 Section 101.13 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.11 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Applicability. 101.11 Section 101.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.33 - Operating limitations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Operating limitations. 101.33 Section 101.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.33 - Operating limitations.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Operating limitations. 101.33 Section 101.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.31 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Applicability. 101.31 Section 101.31 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.13 - Operating limitations.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Operating limitations. 101.13 Section 101.13 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.33 - Operating limitations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Operating limitations. 101.33 Section 101.33 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.13 - Operating limitations.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Operating limitations. 101.13 Section 101.13 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.11 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Applicability. 101.11 Section 101.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

Capacity expansion model of wind power generation based on ELCC

NASA Astrophysics Data System (ADS)

Yuan, Bo; Zong, Jin; Wu, Shengyu

2018-02-01

Capacity expansion is an indispensable prerequisite for power system planning and construction. A reasonable, efficient and accurate capacity expansion model (CEM) is crucial to power system planning. In most current CEMs, the capacity of wind power generation is considered as boundary conditions instead of decision variables, which may lead to curtailment or over construction of flexible resource, especially at a high renewable energy penetration scenario. This paper proposed a wind power generation capacity value(CV) calculation method based on effective load-carrying capability, and a CEM that co-optimizes wind power generation and conventional power sources. Wind power generation is considered as decision variable in this model, and the model can accurately reflect the uncertainty nature of wind power.

76 FR 52966 - Kawailoa Wind Energy Generation Facility, Oahu, HI; Draft Habitat Conservation Plan and Draft...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-24

.... The proposed facility will consist of 30 wind turbine generators (WTGs), a maintenance building, an... sandvicensis), and Hawaiian hoary bat, which have collided with the wind turbine structures at this existing 30... (collisions with wind turbine generators). In addition to the anticipated take by the project, predator...

75 FR 60102 - South Dakota PrairieWinds Project (DOE/EIS-0418)

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-29

... feature 101 wind turbine generators; 6,000 square-foot operations and maintenance building and fence... generation facility that would feature 101 wind turbine generators; 6,000 square-foot operations and... turbine generators, operations and maintenance building and fence perimeter, underground communication...

Emissions impacts of wind and energy storage in a market environment.

PubMed

Sioshansi, Ramteen

2011-12-15

This study examines the emissions impacts of adding wind and energy storage to a market-based electric power system. Using Texas as a case study, we demonstrate that market power can greatly effect the emissions benefits of wind, due to most of the coal-fired generation being owned by the two dominant firms. Wind tends to have less emissions benefits when generators exercise market power, since coal-fired generation is withheld from the market and wind displaces natural gas-fired generators. We also show that storage can have greater negative emissions impacts in the presence of wind than if only storage is added to the system. This is due to wind increasing on- and off-peak electricity price differences, which increases the amount that storage and coal-fired generation are used. We demonstrate that this effect is exacerbated by market power.

Power quality control of an autonomous wind-diesel power system based on hybrid intelligent controller.

PubMed

Ko, Hee-Sang; Lee, Kwang Y; Kang, Min-Jae; Kim, Ho-Chan

2008-12-01

Wind power generation is gaining popularity as the power industry in the world is moving toward more liberalized trade of energy along with public concerns of more environmentally friendly mode of electricity generation. The weakness of wind power generation is its dependence on nature-the power output varies in quite a wide range due to the change of wind speed, which is difficult to model and predict. The excess fluctuation of power output and voltages can influence negatively the quality of electricity in the distribution system connected to the wind power generation plant. In this paper, the authors propose an intelligent adaptive system to control the output of a wind power generation plant to maintain the quality of electricity in the distribution system. The target wind generator is a cost-effective induction generator, while the plant is equipped with a small capacity energy storage based on conventional batteries, heater load for co-generation and braking, and a voltage smoothing device such as a static Var compensator (SVC). Fuzzy logic controller provides a flexible controller covering a wide range of energy/voltage compensation. A neural network inverse model is designed to provide compensating control amount for a system. The system can be optimized to cope with the fluctuating market-based electricity price conditions to lower the cost of electricity consumption or to maximize the power sales opportunities from the wind generation plant.

78 FR 6316 - Big Blue Wind Farm, LLC, et al.; Notice of Effectiveness of Exempt Wholesale Generator Status

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-30

... Wind Farm, LLC, et al.; Notice of Effectiveness of Exempt Wholesale Generator Status Docket Nos. Big Blue Wind Farm, LLC EG13-1-000 Calpine Bosque Energy Center, LLC EG13-2-000 Homer City Generation, L.P EG13-3-000 Texas Dispatchable Wind 1, LLC EG13-4-000 Blue Creek Wind Farm LLC EG13-5-000 Take notice...

Large wind turbines: A utility option for the generation of electricity

NASA Technical Reports Server (NTRS)

Robbins, W. H.; Thomas, R. L.; Baldwin, D. H.

1980-01-01

The wind resource is such that wind energy generation has the potential to save 6-7 quads of energy nationally. Thus, the Federal Government is sponsoring and encouraging the development of cost effective and reliable wind turbines. One element of the Federal Wind Energy Programs, Large Horizontal Axis Wind Turbine Development, is managed by the NASA Lewis Research Center for the Department of Energy. There are several ongoing wind system development projects oriented primarily toward utility application within this program element. In addition, a comprehensive technology program supporting the wind turbine development projects is being conducted. An overview is presented of the NASA activities with emphasis on application of large wind turbines for generation of electricity by utility systems.

Technology Performance Report: Duke Energy Notrees Wind Storage Demonstration Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wehner, Jeff; Mohler, David; Gibson, Stuart

2015-11-01

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

14 CFR 101.19 - Rapid deflation device.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Rapid deflation device. 101.19 Section 101.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.19 - Rapid deflation device.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Rapid deflation device. 101.19 Section 101.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.15 - Notice requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Notice requirements. 101.15 Section 101.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.37 - Notice requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Notice requirements. 101.37 Section 101.37 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.15 - Notice requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Notice requirements. 101.15 Section 101.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.19 - Rapid deflation device.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Rapid deflation device. 101.19 Section 101.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.19 - Rapid deflation device.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Rapid deflation device. 101.19 Section 101.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.37 - Notice requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Notice requirements. 101.37 Section 101.37 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.15 - Notice requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Notice requirements. 101.15 Section 101.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.39 - Balloon position reports.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Balloon position reports. 101.39 Section 101.39 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.37 - Notice requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Notice requirements. 101.37 Section 101.37 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.39 - Balloon position reports.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Balloon position reports. 101.39 Section 101.39 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.39 - Balloon position reports.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Balloon position reports. 101.39 Section 101.39 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.39 - Balloon position reports.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Balloon position reports. 101.39 Section 101.39 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.15 - Notice requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Notice requirements. 101.15 Section 101.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.37 - Notice requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Notice requirements. 101.37 Section 101.37 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.15 - Notice requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Notice requirements. 101.15 Section 101.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Moored...

14 CFR 101.37 - Notice requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Notice requirements. 101.37 Section 101.37 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS...

14 CFR 101.39 - Balloon position reports.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Balloon position reports. 101.39 Section 101.39 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.19 - Rapid deflation device.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Rapid deflation device. 101.19 Section 101.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

40 CFR 53.42 - Generation of test atmospheres for wind tunnel tests.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Generation of test atmospheres for wind... Testing Performance Characteristics of Methods for PM10 § 53.42 Generation of test atmospheres for wind... particle delivery system shall consist of a blower system and a wind tunnel having a test section of...

40 CFR 53.42 - Generation of test atmospheres for wind tunnel tests.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 5 2011-07-01 2011-07-01 false Generation of test atmospheres for wind... Testing Performance Characteristics of Methods for PM10 § 53.42 Generation of test atmospheres for wind... particle delivery system shall consist of a blower system and a wind tunnel having a test section of...

Local inertial oscillations in the surface ocean generated by time-varying winds

NASA Astrophysics Data System (ADS)

Chen, Shengli; Polton, Jeff A.; Hu, Jianyu; Xing, Jiuxing

2015-12-01

A new relationship is presented to give a review study on the evolution of inertial oscillations in the surface ocean locally generated by time-varying wind stress. The inertial oscillation is expressed as the superposition of a previous oscillation and a newly generated oscillation, which depends upon the time-varying wind stress. This relationship is employed to investigate some idealized wind change events. For a wind series varying temporally with different rates, the induced inertial oscillation is dominated by the wind with the greatest variation. The resonant wind, which rotates anti-cyclonically at the local inertial frequency with time, produces maximal amplitude of inertial oscillations, which grows monotonically. For the wind rotating at non-inertial frequencies, the responses vary periodically, with wind injecting inertial energy when it is in phase with the currents, but removing inertial energy when it is out of phase. The wind rotating anti-cyclonically with time is much more favorable to generate inertial oscillations than the cyclonic rotating wind. The wind with a frequency closer to the inertial frequency generates stronger inertial oscillations. For a diurnal wind, the induced inertial oscillation is dependent on latitude and is most significant at 30 °. This relationship is also applied to examine idealized moving cyclones. The inertial oscillation is much stronger on the right-hand side of the cyclone path than on the left-hand side (in the northern hemisphere). This is due to the wind being anti-cyclonic with time on the right-hand side, but cyclonic on the other side. The inertial oscillation varies with the cyclone translation speed. The optimal translation speed generating the greatest inertial oscillations is 2 m/s at the latitude of 10 ° and gradually increases to 6 m/s at the latitude of 30 °.

Synchronous Generators with Superconductive Excitation Windings,

DTIC Science & Technology

1983-07-27

AD-Al3i 832 SYNCHRONOUS GENERATORS WITH SUPERCONDUCTIVE EXCITATION i/i WINDINGS(U) FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OH W PASZEK ET AL. 27...1.1 FTD-ID(RS)T-1087-83 FOREIGN TECHNOLOGY DIVISION SYNCHRONOUS GENERATORS WITH SUPERCONDUCTIVE EXCITATION WINDINGS by W. Paszek and A. Rozycki DTIC...MICROFICHE NR: FTD-83-C-000906 j.r.voiFor SYNCHRONOUS GENERATORS WITH SUPERCONDUCTIVE T EXCITATION WINDINGS 0;~f~on~ SJustification By: W./Paszek and A

Plans and status of the NASA-Lewis Research Center wind energy project

NASA Technical Reports Server (NTRS)

Thomas, R.; Puthoff, R.; Savino, J.; Johnson, W.

1975-01-01

This report describes that portion of the national five-year wind energy program that is being managed by the NASA-Lewis Research Center for the ERDA. The Lewis Research Center's Wind Power Office, its organization and plans and status are briefly described. The three major elements of the wind energy project at Lewis are the experimental 100 kW wind-turbine generator; the first generation industry-built and user-operated wind turbine generators; and the supporting research and technology tasks which are each briefly described.

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

PubMed Central

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

2015-01-01

Wind turbines remove kinetic energy from the atmospheric flow, which reduces wind speeds and limits generation rates of large wind farms. These interactions can be approximated using a vertical kinetic energy (VKE) flux method, which predicts that the maximum power generation potential is 26% of the instantaneous downward transport of kinetic energy using the preturbine climatology. We compare the energy flux method to the Weather Research and Forecasting (WRF) regional atmospheric model equipped with a wind turbine parameterization over a 105 km2 region in the central United States. The WRF simulations yield a maximum generation of 1.1 We⋅m−2, whereas the VKE method predicts the time series while underestimating the maximum generation rate by about 50%. Because VKE derives the generation limit from the preturbine climatology, potential changes in the vertical kinetic energy flux from the free atmosphere are not considered. Such changes are important at night when WRF estimates are about twice the VKE value because wind turbines interact with the decoupled nocturnal low-level jet in this region. Daytime estimates agree better to 20% because the wind turbines induce comparatively small changes to the downward kinetic energy flux. This combination of downward transport limits and wind speed reductions explains why large-scale wind power generation in windy regions is limited to about 1 We⋅m−2, with VKE capturing this combination in a comparatively simple way. PMID:26305925

77 FR 55829 - Western Area Power Administration; Grapevine Canyon Wind Project Record of Decision (DOE/EIS-0427)

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-11

... megawatts of electricity from wind turbine generators (WTGs). The proposed project includes a wind energy... about the installation of red flashing lights on wind turbine generators per Federal Aviation... DEPARTMENT OF ENERGY Western Area Power Administration; Grapevine Canyon Wind Project Record of...

Effect of autoclaving on the surfaces of TiN -coated and conventional nickel-titanium rotary instruments.

PubMed

Spagnuolo, G; Ametrano, G; D'Antò, V; Rengo, C; Simeone, M; Riccitiello, F; Amato, M

2012-12-01

To evaluate the effects of repeated autoclave sterilization cycles on surface topography of conventional nickel-titanium ( NiTi ) and titanium nitride ( TiN )-coated rotary instruments. A total of 60 NiTi rotary instruments, 30 ProTaper (Dentsply Maillefer) and 30 TiN -coated AlphaKite (Komet/Gebr. Brasseler), were analysed. Instruments were evaluated in the as-received condition and after 1, 5 and 10 sterilization cycles. After sterilization, the samples were observed using scanning electron microscope (SEM), and surface chemical analysis was performed on each instrument with energy dispersive X-ray spectroscopy (EDS). Moreover, the samples were analysed by atomic force microscopy (AFM), and roughness average (Ra) and the root mean square value (RMS) of the scanned surface profiles were recorded. Data were analysed by means of anova followed by Tukey's test. Scanning electron microscope observations revealed the presence of pitting and deep milling marks in all instruments. EDS analysis confirmed that both types of instruments were composed mainly of nickel and titanium, whilst AlphaKite had additional nitride. After multiple autoclave sterilization cycles, SEM examinations revealed an increase in surface alterations, and EDS values indicated changes in chemical surface composition in all instruments. Ra and RMS values of ProTaper significantly increased after 5 (P = 0.006) and 10 cycles (P = 0.002) with respect to the as-received instruments, whilst AlphaKite showed significant differences compared with the controls after 10 cycles (P = 0.03). Multiple autoclave sterilization cycles modified the surface topography and chemical composition of conventional and TiN -coated NiTi rotary instruments. © 2012 International Endodontic Journal.

Decoration Increases the Conspicuousness of Raptor Nests

PubMed Central

Canal, David; Mulero-Pázmány, Margarita; Negro, Juan José; Sergio, Fabrizio

2016-01-01

Avian nests are frequently concealed or camouflaged, but a number of species builds noticeable nests or use conspicuous materials for nest decoration. In most cases, nest decoration has a role in mate choice or provides thermoregulatory or antiparasitic benefits. In territorial species however, decorations may serve additional or complementary functions, such as extended phenotypic signaling of nest-site occupancy and social status to potential intruders. The latter may benefit both signaler and receiver by minimizing the risk of aggressive interactions, especially in organisms with dangerous weaponry. Support for this hypothesis was recently found in a population of black kites (Milvus migrans), a territorial raptor that decorates its nest with white artificial materials. However, the crucial assumption that nest decorations increased nest-site visibility to conspecifics was not assessed, a key aspect given that black kite nests may be well concealed within the canopy. Here, we used an unmanned aircraft system to take pictures of black kite nests, with and without an experimentally placed decoration, from different altitudes and distances simulating the perspective of a flying and approaching, prospecting intruder. The pictures were shown to human volunteers through a standardized routine to determine whether detection rates varied according the nest decoration status and distance. Decorated nests consistently showed a higher detection frequency and a lower detection-latency, compared to undecorated versions of the same nests. Our results confirm that nest decoration in this species may act as a signaling medium that enhances nest visibility for aerial receivers, even at large distances. This finding complements previous work on this communication system, which showed that nest decoration was a threat informing trespassing conspecifics on the social dominance, territory quality and fighting capabilities of the signaler. PMID:27455066

Decoration Increases the Conspicuousness of Raptor Nests.

PubMed

Canal, David; Mulero-Pázmány, Margarita; Negro, Juan José; Sergio, Fabrizio

2016-01-01

Avian nests are frequently concealed or camouflaged, but a number of species builds noticeable nests or use conspicuous materials for nest decoration. In most cases, nest decoration has a role in mate choice or provides thermoregulatory or antiparasitic benefits. In territorial species however, decorations may serve additional or complementary functions, such as extended phenotypic signaling of nest-site occupancy and social status to potential intruders. The latter may benefit both signaler and receiver by minimizing the risk of aggressive interactions, especially in organisms with dangerous weaponry. Support for this hypothesis was recently found in a population of black kites (Milvus migrans), a territorial raptor that decorates its nest with white artificial materials. However, the crucial assumption that nest decorations increased nest-site visibility to conspecifics was not assessed, a key aspect given that black kite nests may be well concealed within the canopy. Here, we used an unmanned aircraft system to take pictures of black kite nests, with and without an experimentally placed decoration, from different altitudes and distances simulating the perspective of a flying and approaching, prospecting intruder. The pictures were shown to human volunteers through a standardized routine to determine whether detection rates varied according the nest decoration status and distance. Decorated nests consistently showed a higher detection frequency and a lower detection-latency, compared to undecorated versions of the same nests. Our results confirm that nest decoration in this species may act as a signaling medium that enhances nest visibility for aerial receivers, even at large distances. This finding complements previous work on this communication system, which showed that nest decoration was a threat informing trespassing conspecifics on the social dominance, territory quality and fighting capabilities of the signaler.

Stabilization of Wind Energy Conversion System with Hydrogen Generator by Using EDLC Energy Storage System

NASA Astrophysics Data System (ADS)

Shishido, Seiji; Takahashi, Rion; Murata, Toshiaki; Tamura, Junji; Sugimasa, Masatoshi; Komura, Akiyoshi; Futami, Motoo; Ichinose, Masaya; Ide, Kazumasa

The spread of wind power generation is progressed hugely in recent years from a viewpoint of environmental problems including global warming. Though wind power is considered as a very prospective energy source, wind power fluctuation due to the random fluctuation of wind speed has still created some problems. Therefore, research has been performed how to smooth the wind power fluctuation. This paper proposes Energy Capacitor System (ECS) for the smoothing of wind power which consists of Electric Double-Layer Capacitor (EDLC) and power electronics devices and works as an electric power storage system. Moreover, hydrogen has received much attention in recent years from a viewpoint of exhaustion problem of fossil fuel. Therefore it is also proposed that a hydrogen generator is installed at the wind farm to generate hydrogen. In this paper, the effectiveness of the proposed system is verified by the simulation analyses using PSCAD/EMTDC.

Power Control for Direct-Driven Permanent Magnet Wind Generator System with Battery Storage

PubMed Central

Guang, Chu Xiao; Ying, Kong

2014-01-01

The objective of this paper is to construct a wind generator system (WGS) loss model that addresses the loss of the wind turbine and the generator. It aims to optimize the maximum effective output power and turbine speed. Given that the wind generator system has inertia and is nonlinear, the dynamic model of the wind generator system takes the advantage of the duty of the Buck converter and employs feedback linearization to design the optimized turbine speed tracking controller and the load power controller. According to that, this paper proposes a dual-mode dynamic coordination strategy based on the auxiliary load to reduce the influence of mode conversion on the lifetime of the battery. Optimized speed and power rapid tracking as well as the reduction of redundant power during mode conversion have gone through the test based on a 5 kW wind generator system test platform. The generator output power as the capture target has also been proved to be efficient. PMID:25050405

Power control for direct-driven permanent magnet wind generator system with battery storage.

PubMed

Guang, Chu Xiao; Ying, Kong

2014-01-01

The objective of this paper is to construct a wind generator system (WGS) loss model that addresses the loss of the wind turbine and the generator. It aims to optimize the maximum effective output power and turbine speed. Given that the wind generator system has inertia and is nonlinear, the dynamic model of the wind generator system takes the advantage of the duty of the Buck converter and employs feedback linearization to design the optimized turbine speed tracking controller and the load power controller. According to that, this paper proposes a dual-mode dynamic coordination strategy based on the auxiliary load to reduce the influence of mode conversion on the lifetime of the battery. Optimized speed and power rapid tracking as well as the reduction of redundant power during mode conversion have gone through the test based on a 5 kW wind generator system test platform. The generator output power as the capture target has also been proved to be efficient.

Regional Wave Climates along Eastern Boundary Currents

NASA Astrophysics Data System (ADS)

Semedo, Alvaro; Soares, Pedro

2016-04-01

Two types of wind-generated gravity waves coexist at the ocean surface: wind sea and swell. Wind sea waves are waves under growing process. These young growing waves receive energy from the overlaying wind and are strongly coupled to the local wind field. Waves that propagate away from their generation area and no longer receive energy input from the local wind are called swell. Swell waves can travel long distances across entire ocean basins. A qualitative study of the ocean waves from a locally vs. remotely generation perspective is important, since the air sea interaction processes is strongly modulated by waves and vary accordingly to the prevalence of wind sea or swell waves in the area. A detailed climatology of wind sea and swell waves along eastern boundary currents (EBC; California Current, Canary Current, in the Northern Hemisphere, and Humboldt Current, Benguela Current, and Western Australia Current, in the Southern Hemisphere), based on the ECMWF (European Centre for Medium-Range Weather Forecasts) ERA-Interim reanalysis will be presented. The wind regime along EBC varies significantly from winter to summer. The high summer wind speeds along EBC generate higher locally generated wind sea waves, whereas lower winter wind speeds in these areas, along with stronger winter extratropical storms far away, lead to a predominance of swell waves there. In summer, the coast parallel winds also interact with coastal headlands, increasing the wind speed through a process called "expansion fan", which leads to an increase in the height of locally generated waves downwind of capes and points. Hence the spatial patterns of the wind sea or swell regional wave fields are shown to be different from the open ocean along EBC, due to coastal geometry and fetch dimensions. Swell waves will be shown to be considerably more prevalent and to carry more energy in winter along EBC, while in summer locally generated wind sea waves are either more comparable to swell waves or, particularly in the lee of headlands, or even more prevalent and more energized than swell. This study is part of the WRCP-JCOMM COWCLIP (Coordinated Ocean Wave Climate Project) effort.

Performance ‘S’ Type Savonius Wind Turbine with Variation of Fin Addition on Blade

NASA Astrophysics Data System (ADS)

Pamungkas, S. F.; Wijayanto, D. S.; Saputro, H.; Widiastuti, I.

2018-01-01

Wind power has been receiving attention as the new energy resource in addressing the ecological problems of burning fossil fuels. Savonius wind rotor is a vertical axis wind turbines (VAWT) which has relatively simple structure and low operating speed. These characteristics make it suitable for areas with low average wind speed as in Indonesia. To identify the performance of Savonius rotor in generating electrical energy, this research experimentally studied the effect of fin addition for the ‘S’ shape of Savonius VAWT. The fin is added to fill the space in the blade in directing the wind flow. This rotor has two turbine blades, a rotor diameter of 1.1 m and rotor height of 1.4 m, used pulley transmission system with 1:4.2 multiplication ratio, and used a generator type PMG 200 W. The research was conducted during dry season by measuring the wind speed in the afternoon. The average wind speed in the area is 2.3 m/s with the maximum of 4.5 m/s. It was found that additional fin significantly increase the ability of Savonius rotor VAWT to generate electrical energy shown by increasing of electrical power. The highest power generated is 13.40 Watt at a wind speed of 4.5 m/s by adding 1 (one) fin in the blade. It increased by 22.71% from the rotor blade with no additional fin. However, increasing number of fins in the blade was not linearly increase the electrical power generated. The wind rotor blade with 4 additional fins is indicated has the lowest performance, generating only 10.80 Watt electrical power, accounted lower than the one generated by no fin-rotor blade. By knowing the effect of the rotor shape, the rotor dimension, the addition of fin, transmission, and generator used, it is possible to determine alternative geometry design in increasing the electrical power generated by Savonius wind turbine.

Design and comparative analysis of 10 MW class superconducting wind power generators according to different types of superconducting wires

NASA Astrophysics Data System (ADS)

Sung, Hae-Jin; Kim, Gyeong-Hun; Kim, Kwangmin; Park, Minwon; Yu, In-Keun; Kim, Jong-Yul

2013-11-01

Wind turbine concepts can be classified into the geared type and the gearless type. The gearless type wind turbine is more attractive due to advantages of simplified drive train and increased energy yield, and higher reliability because the gearbox is omitted. In addition, this type resolves the weight issue of the wind turbine with the light weight of gearbox. However, because of the low speed operation, this type has disadvantage such as the large diameter and heavy weight of generator. Super-Conducting (SC) wind power generator can reduce the weight and volume of a wind power system. Properties of superconducting wire are very different from each company. This paper considers the design and comparative analysis of 10 MW class SC wind power generators according to different types of SC wires. Super-Conducting Synchronous Generators (SCSGs) using YBCO and Bi-2223 wires are optimized by an optimal method. The magnetic characteristics of the SCSGs are investigated using the finite elements method program. The optimized specifications of the SCSGs are discussed in detail, and the optimization processes can be used effectively to develop large scale wind power generation systems.

Impact of wind generator infed on dynamic performance of a power system

NASA Astrophysics Data System (ADS)

Alam, Md. Ahsanul

Wind energy is one of the most prominent sources of electrical energy in the years to come. A tendency to increase the amount of electricity generation from wind turbine can be observed in many countries. One of the major concerns related to the high penetration level of the wind energy into the existing power grid is its influence on power system dynamic performance. In this thesis, the impact of wind generation system on power system dynamic performance is investigated through detailed dynamic modeling of the entire wind generator system considering all the relevant components. Nonlinear and linear models of a single machine as well as multimachine wind-AC system have been derived. For the dynamic model of integrated wind-AC system, a general transformation matrix is determined for the transformation of machine and network quantities to a common reference frame. Both time-domain and frequency domain analyses on single machine and multimachine systems have been carried out. The considered multimachine systems are---A 4 machine 12 bus system, and 10 machine 39 bus New England system. Through eigenvalue analysis, impact of asynchronous wind system on overall network damping has been quantified and modes responsible for the instability have been identified. Over with a number of simulation studies it is observed that for a induction generator based wind generation system, the fixed capacitor located at the generator terminal cannot normally cater for the reactive power demand during the transient disturbances like wind gust and fault on the system. For weak network connection, system instability may be initiated because of induction generator terminal voltage collapse under certain disturbance conditions. Incorporation of dynamic reactive power compensation scheme through either variable susceptance control or static compensator (STATCOM) is found to improve the dynamic performance significantly. Further improvement in transient profile has been brought in by supporting STATCOM with bulk energy storage devices. Two types of energy storage system (ESS) have been considered---battery energy storage system, and supercapacitor based energy storage system. A decoupled P -- Q control strategy has been implemented on STATCOM/ESS. It is observed that wind generators when supported by STATCOM/ESS can achieve significant withstand capability in the presence of grid fault of reasonable duration. It experiences almost negligible rotor speed variation, maintains constant terminal voltage, and resumes delivery of smoothed (almost transient free) power to the grid immediately after the fault is cleared. Keywords: Wind energy, induction generator, dynamic performance of wind generators, energy storage system, decoupled P -- Q control, multimachine system.

14 CFR 101.3 - Waivers.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Waivers. 101.3 Section 101.3 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.3...

14 CFR 101.35 - Equipment and marking requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Equipment and marking requirements. 101.35 Section 101.35 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.3 - Waivers.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Waivers. 101.3 Section 101.3 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.3...

14 CFR 101.3 - Waivers.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Waivers. 101.3 Section 101.3 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.3...

14 CFR 101.3 - Waivers.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Waivers. 101.3 Section 101.3 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.3...

14 CFR 101.35 - Equipment and marking requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Equipment and marking requirements. 101.35 Section 101.35 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.3 - Waivers.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Waivers. 101.3 Section 101.3 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS General § 101.3...

14 CFR 101.17 - Lighting and marking requirements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Lighting and marking requirements. 101.17 Section 101.17 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.17 - Lighting and marking requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Lighting and marking requirements. 101.17 Section 101.17 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.35 - Equipment and marking requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Equipment and marking requirements. 101.35 Section 101.35 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.17 - Lighting and marking requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Lighting and marking requirements. 101.17 Section 101.17 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.17 - Lighting and marking requirements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Lighting and marking requirements. 101.17 Section 101.17 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.35 - Equipment and marking requirements.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Equipment and marking requirements. 101.35 Section 101.35 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.35 - Equipment and marking requirements.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Equipment and marking requirements. 101.35 Section 101.35 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

14 CFR 101.17 - Lighting and marking requirements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Lighting and marking requirements. 101.17 Section 101.17 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE...

Perspectives on Science Writing.

ERIC Educational Resources Information Center

Krieghbaum, Hillier

Science journalism in the United States can be traced back to at least 1690 when a newspaper called "Publick Occurrences" included two paragraphs of medical writing in one issue. In 1752, the "Pennsylvania Gazette" carried an account by Benjamin Franklin of his "electric kite" experiment. Since then, inventions and…

A New Dimension for Earth Science Learning

NASA Astrophysics Data System (ADS)

Bland, G.; Henry, A.; Bydlowski, D.

2017-12-01

NASA Science Objectives include capturing the global view of Earth from space. This unique perspective is often augmented by instrumented research aircraft, to provide in-situ and remote sensing observations in support of the world picture. Our "Advancing Earth Research Observations with Kites and Atmospheric /Terrestrial Sensors" (AEROKATS) project aims to bring this novel and exciting perspective into the hands of learners young and old. The practice of using instrumented kites as surrogate satellites and aircraft is gaining momentum, as our team undertakes the technical, operational, and scientific challenges in preparations to bring new and easy-to-field tools to broad audiences. The third dimension in spatial perception ("up") has previously been difficult to effectively incorporate in learning and local-scale research activities. AEROKATS brings simple to use instrumented aerial systems into the hands of students, educators, and scientists, with the tangible benefits of detailed, high resolution measurements and observations directly applicable to real-world studies of the environments around us.

Summary of atmospheric wind design criteria for wind energy conversion system development

NASA Technical Reports Server (NTRS)

Frost, W.; Turner, R. E.

1979-01-01

Basic design values are presented of significant wind criteria, in graphical format, for use in the design and development of wind turbine generators for energy research. It is a condensed version of portions of the Engineering Handbook on the Atmospheric Environmental Guidelines for Use in Wind Turbine Generator Development.

Novel design configurations for permanent magnet wind generators

NASA Astrophysics Data System (ADS)

Chen, Yicheng

2004-12-01

The aim of this research is to search for optimal designs of permanent magnet (PM) wind generators of different topologies. The dissertation deals with the development of analytical design equations and formulas for PM wind generators of different topologies, including equivalent magnetic circuit model for magnets, calculation of leakage flux, influence of d-q axis armature reaction, flux waveform analysis, as well as performance verification. 3-D and simplified 2-D finite element analysis is used to enhance the design precision, by which analytical formulas are modified. A new and improved formula is proposed for lamination loss calculations, based on a large experimental data set provided by steel manufacturers. The temperature stability of NdFeB magnets is analyzed and some proposals for eliminating irreversible demagnetization are presented. Two existing experimental machines are used to validate the design equations. The genetic algorithms are used to investigate the multi-objective design optimization of PM wind generators for a high efficiency and light-weight design. The reasoning behind the selection of the objective functions, design variables and constraints are given as guidance for the PM wind generator optimum design. The implementation of the genetic algorithm is also given. A comparison of PM wind generators of different topologies is presented. Conclusions are drawn for topology selections of PM wind generators. The group of soft magnetic composites (SMC) has recently been expanded by the introduction of new materials with significantly improved frequency properties. This has made SMC a viable alternative to steel laminations for a range of new applications, especially axial-flux wind generators. The isotropic nature of the SMC combined with the unique shaping possibilities opens up new design solutions for axial-flux wind generators. Through careful design, an axial-flux PM wind generator with SMC core is built and tested, demonstrating the advantages of better performance, reduced size and weight, fewer parts and lower cost.

Turbulent Extreme Event Simulations for Lidar-Assisted Wind Turbine Control

NASA Astrophysics Data System (ADS)

Schlipf, David; Raach, Steffen

2016-09-01

This work presents a wind field generator which allows to shape wind fields in the time domain while maintaining the spectral properties. This is done by an iterative generation of wind fields and by minimizing the error between wind characteristics of the generated wind fields and desired values. The method leads towards realistic ultimate load calculations for lidar-assisted control. This is demonstrated by fitting a turbulent wind field to an Extreme Operating Gust. The wind field is then used to compare a baseline feedback controller alone against a combined feedback and feedforward controller using simulated lidar measurements. The comparison confirms that the lidar-assisted controller is still able to significantly reduce the ultimate loads on the tower base under this more realistic conditions.

Design of a 3 kW wind turbine generator with thin airfoil blades

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ameku, Kazumasa; Nagai, Baku M.; Roy, Jitendro Nath

2008-09-15

Three blades of a 3 kW prototype wind turbine generator were designed with thin airfoil and a tip speed ratio of 3. The wind turbine has been controlled via two control methods: the variable pitch angle and by regulation of the field current of the generator and examined under real wind conditions. The characteristics of the thin airfoil, called ''Seven arcs thin airfoil'' named so because the airfoil is composed of seven circular arcs, are analyzed with the airfoil design and analysis program XFOIL. The thin airfoil blade is designed and calculated by blade element and momentum theory. The performancemore » characteristics of the machine such as rotational speed, generator output as well as stability for wind speed changes are described. In the case of average wind speeds of 10 m/s and a maximum of 19 m/s, the automatically controlled wind turbine ran safely through rough wind conditions and showed an average generator output of 1105 W and a power coefficient 0.14. (author)« less

Development of large wind energy power generation system

NASA Technical Reports Server (NTRS)

1985-01-01

The background and development of an experimental 100 kW wind-energy generation system are described, and the results of current field tests are presented. The experimental wind turbine is a two-bladed down-wind horizontal axis propeller type with a 29.4 m diameter rotor and a tower 28 m in height. The plant was completed in March, 1983, and has been undergoing trouble-free tests since then. The present program calls for field tests during two years from fiscal 1983 to 1984. The development of technologies relating to the linkage and operation of wind-energy power generation system networks is planned along with the acquisition of basic data for the development of a large-scale wind energy power generation system.

Use of wind turbines to generate electricity for highway buildings.

DOT National Transportation Integrated Search

1983-01-01

To determine the feasibility of using wind turbines to generate electrical power, measurements of wind speeds were made for a period of one year at three installations of the Virginia Department of Highways and Transportation. Unfortunately, the wind...

Wind power. [electricity generation

NASA Technical Reports Server (NTRS)

Savino, J. M.

1975-01-01

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

Wind Generators

NASA Technical Reports Server (NTRS)

1989-01-01

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

Wind turbine/generator set and method of making same

DOEpatents

Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.

2013-06-04

A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle via a bearing assembly. The wind rotor hub includes an opening having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity inside the wind rotor hub. The spindle is attached to a turret supported by a tower. Each of the spindle, turret and tower has an interior cavity that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.

Wind turbine/generator set having a stator cooling system located between stator frame and active coils

DOEpatents

Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.

2012-11-13

A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle via a bearing assembly. The wind rotor hub includes an opening having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity inside the wind rotor hub. The spindle is attached to a turret supported by a tower. Each of the spindle, turret and tower has an interior cavity that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.

Introduction to Voigt's wind power plant. [energy conversion efficiency

NASA Technical Reports Server (NTRS)

Tompkin, J.

1973-01-01

The design and operation of a 100 kilowatt wind driven generator are reported. Its high speed three-bladed turbine operates at a height of 50 meters. Blades are rigidly connected to the hub and turbine revolutions change linearly with wind velocity, maintaining a constant speed ratio of blade tip velocity to wind velocity over the full predetermined wind range. Three generators installed in the gondola generate either dc or ac current. Based on local wind conditions, the device has a maximum output of 720 kilowatts at a wind velocity of 16 meters per second. Total electrical capacity is 750 kilowatts, and power output per year is 2,135,000 kilowatt/hours.

NASA Tech Briefs, April 2012

NASA Technical Reports Server (NTRS)

2012-01-01

Topics include: Computational Ghost Imaging for Remote Sensing; Digital Architecture for a Trace Gas Sensor Platform; Dispersed Fringe Sensing Analysis - DFSA; Indium Tin Oxide Resistor-Based Nitric Oxide Microsensors; Gas Composition Sensing Using Carbon Nanotube Arrays; Sensor for Boundary Shear Stress in Fluid Flow; Model-Based Method for Sensor Validation; Qualification of Engineering Camera for Long-Duration Deep Space Missions; Remotely Powered Reconfigurable Receiver for Extreme Environment Sensing Platforms; Bump Bonding Using Metal-Coated Carbon Nanotubes; In Situ Mosaic Brightness Correction; Simplex GPS and InSAR Inversion Software; Virtual Machine Language 2.1; Multi-Scale Three-Dimensional Variational Data Assimilation System for Coastal Ocean Prediction; Pandora Operation and Analysis Software; Fabrication of a Cryogenic Bias Filter for Ultrasensitive Focal Plane; Processing of Nanosensors Using a Sacrificial Template Approach; High-Temperature Shape Memory Polymers; Modular Flooring System; Non-Toxic, Low-Freezing, Drop-In Replacement Heat Transfer Fluids; Materials That Enhance Efficiency and Radiation Resistance of Solar Cells; Low-Cost, Rugged High-Vacuum System; Static Gas-Charging Plug; Floating Oil-Spill Containment Device; Stemless Ball Valve; Improving Balance Function Using Low Levels of Electrical Stimulation of the Balance Organs; Oxygen-Methane Thruster; Lunar Navigation Determination System - LaNDS; Launch Method for Kites in Low-Wind or No-Wind Conditions; Supercritical CO2 Cleaning System for Planetary Protection and Contamination Control Applications; Design and Performance of a Wideband Radio Telescope; Finite Element Models for Electron Beam Freeform Fabrication Process Autonomous Information Unit for Fine-Grain Data Access Control and Information Protection in a Net-Centric System; Vehicle Detection for RCTA/ANS (Autonomous Navigation System); Image Mapping and Visual Attention on the Sensory Ego-Sphere; HyDE Framework for Stochastic and Hybrid Model-Based Diagnosis; and IMAGESEER - IMAGEs for Education and Research.

Wind energy: A renewable energy option

NASA Technical Reports Server (NTRS)

Zimmerman, J. S.

1977-01-01

Wind turbine generator research programs administered by the Energy Research and Development Administration are examined. The design and operation of turbine demonstration models are described. Wind assessments were made to determine the feasibility of using wind generated power for various parts of the country.

Method and apparatus for wind turbine air gap control

DOEpatents

Grant, James Jonathan; Bagepalli, Bharat Sampathkumaran; Jansen, Patrick Lee; DiMascio, Paul Stephen; Gadre, Aniruddha Dattatraya; Qu, Ronghai

2007-02-20

Methods and apparatus for assembling a wind turbine generator are provided. The wind turbine generator includes a core and a plurality of stator windings circumferentially spaced about a generator longitudinal axis, a rotor rotatable about the generator longitudinal axis wherein the rotor includes a plurality of magnetic elements coupled to a radially outer periphery of the rotor such that an airgap is defined between the stator windings and the magnetic elements and the plurality of magnetic elements including a radially inner periphery having a first diameter. The wind turbine generator also includes a bearing including a first member in rotatable engagement with a radially inner second member, the first member including a radially outer periphery, a diameter of the radially outer periphery of the first member being substantially equal to the first diameter, the rotor coupled to the stator through the bearing such that a substantially uniform airgap is maintained.

Wind and solar powered turbine

NASA Technical Reports Server (NTRS)

Wells, I. D.; Koh, J. L.; Holmes, M. (Inventor)

1984-01-01

A power generating station having a generator driven by solar heat assisted ambient wind is described. A first plurality of radially extendng air passages direct ambient wind to a radial flow wind turbine disposed in a centrally located opening in a substantially disc-shaped structure. A solar radiation collecting surface having black bodies is disposed above the fist plurality of air passages and in communication with a second plurality of radial air passages. A cover plate enclosing the second plurality of radial air passages is transparent so as to permit solar radiation to effectively reach the black bodies. The second plurality of air passages direct ambient wind and thermal updrafts generated by the black bodies to an axial flow turbine. The rotating shaft of the turbines drive the generator. The solar and wind drien power generating system operates in electrical cogeneration mode with a fuel powered prime mover.

Wind Velocity and Position Sensor-less Operation for PMSG Wind Generator

NASA Astrophysics Data System (ADS)

Senjyu, Tomonobu; Tamaki, Satoshi; Urasaki, Naomitsu; Uezato, Katsumi; Funabashi, Toshihisa; Fujita, Hideki

Electric power generation using non-conventional sources is receiving considerable attention throughout the world. Wind energy is one of the available non-conventional energy sources. Electrical power generation using wind energy is possible in two ways, viz. constant speed operation and variable speed operation using power electronic converters. Variable speed power generation is attractive, because maximum electric power can be generated at all wind velocities. However, this system requires a rotor speed sensor, for vector control purpose, which increases the cost of the system. To alleviate the need of rotor speed sensor in vector control, we propose a new sensor-less control of PMSG (Permanent Magnet Synchronous Generator) based on the flux linkage. We can estimate the rotor position using the estimated flux linkage. We use a first-order lag compensator to obtain the flux linkage. Furthermore‚we estimate wind velocity and rotation speed using a observer. The effectiveness of the proposed method is demonstrated thorough simulation results.

The value of improved wind power forecasting: Grid flexibility quantification, ramp capability analysis, and impacts of electricity market operation timescales

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Qin; Wu, Hongyu; Florita, Anthony R.

The value of improving wind power forecasting accuracy at different electricity market operation timescales was analyzed by simulating the IEEE 118-bus test system as modified to emulate the generation mixes of the Midcontinent, California, and New England independent system operator balancing authority areas. The wind power forecasting improvement methodology and error analysis for the data set were elaborated. Production cost simulation was conducted on the three emulated systems with a total of 480 scenarios, considering the impacts of different generation technologies, wind penetration levels, and wind power forecasting improvement timescales. The static operational flexibility of the three systems was comparedmore » through the diversity of generation mix, the percentage of must-run baseload generators, as well as the available ramp rate and the minimum generation levels. The dynamic operational flexibility was evaluated by the real-time upward and downward ramp capacity. Simulation results show that the generation resource mix plays a crucial role in evaluating the value of improved wind power forecasting at different timescales. In addition, the changes in annual operational electricity generation costs were mostly influenced by the dominant resource in the system. Lastly, the impacts of pumped-storage resources, generation ramp rates, and system minimum generation level requirements on the value of improved wind power forecasting were also analyzed.« less

The value of improved wind power forecasting: Grid flexibility quantification, ramp capability analysis, and impacts of electricity market operation timescales

DOE PAGES

Wang, Qin; Wu, Hongyu; Florita, Anthony R.; ...

2016-11-11

The value of improving wind power forecasting accuracy at different electricity market operation timescales was analyzed by simulating the IEEE 118-bus test system as modified to emulate the generation mixes of the Midcontinent, California, and New England independent system operator balancing authority areas. The wind power forecasting improvement methodology and error analysis for the data set were elaborated. Production cost simulation was conducted on the three emulated systems with a total of 480 scenarios, considering the impacts of different generation technologies, wind penetration levels, and wind power forecasting improvement timescales. The static operational flexibility of the three systems was comparedmore » through the diversity of generation mix, the percentage of must-run baseload generators, as well as the available ramp rate and the minimum generation levels. The dynamic operational flexibility was evaluated by the real-time upward and downward ramp capacity. Simulation results show that the generation resource mix plays a crucial role in evaluating the value of improved wind power forecasting at different timescales. In addition, the changes in annual operational electricity generation costs were mostly influenced by the dominant resource in the system. Lastly, the impacts of pumped-storage resources, generation ramp rates, and system minimum generation level requirements on the value of improved wind power forecasting were also analyzed.« less

Wind speed reductions by large-scale wind turbine deployments lower turbine efficiencies and set low generation limits.

PubMed

Miller, Lee M; Kleidon, Axel

2016-11-29

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

Wind speed reductions by large-scale wind turbine deployments lower turbine efficiencies and set low generation limits

PubMed Central

Miller, Lee M.; Kleidon, Axel

2016-01-01

Wind turbines generate electricity by removing kinetic energy from the atmosphere. Large numbers of wind turbines are likely to reduce wind speeds, which lowers estimates of electricity generation from what would be presumed from unaffected conditions. Here, we test how well wind power limits that account for this effect can be estimated without explicitly simulating atmospheric dynamics. We first use simulations with an atmospheric general circulation model (GCM) that explicitly simulates the effects of wind turbines to derive wind power limits (GCM estimate), and compare them to a simple approach derived from the climatological conditions without turbines [vertical kinetic energy (VKE) estimate]. On land, we find strong agreement between the VKE and GCM estimates with respect to electricity generation rates (0.32 and 0.37 We m−2) and wind speed reductions by 42 and 44%. Over ocean, the GCM estimate is about twice the VKE estimate (0.59 and 0.29 We m−2) and yet with comparable wind speed reductions (50 and 42%). We then show that this bias can be corrected by modifying the downward momentum flux to the surface. Thus, large-scale limits to wind power use can be derived from climatological conditions without explicitly simulating atmospheric dynamics. Consistent with the GCM simulations, the approach estimates that only comparatively few land areas are suitable to generate more than 1 We m−2 of electricity and that larger deployment scales are likely to reduce the expected electricity generation rate of each turbine. We conclude that these atmospheric effects are relevant for planning the future expansion of wind power. PMID:27849587

76 FR 76153 - Notice of Effectiveness of Exempt Wholesale Generator Status; Caney River Wind Project, LLC...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-06

...] Notice of Effectiveness of Exempt Wholesale Generator Status; Caney River Wind Project, LLC, Mesquite Solar 1, LLC, Copper Crossing Solar LLC, Copper Mountain Solar 1, LLC, Pinnacle Wind, LLC, Bellevue Solar, LLC, Yamhill Solar, LLC, Osage Wind, LLC, Minco Wind II, LLC Take notice that during the month of...

Charles L. Brewer Distinguished Teaching of Psychology Award.

PubMed

2014-01-01

The American Psychological Foundation (APF) Charles L. Brewer Award for Distinguished Teaching of Psychology recognizes an outstanding career contribution to the teaching of psychology. The 2014 recipient of the Charles L. Brewer Distinguished Teaching of Psychology Award is Mary E. Kite. 2014 APA, all rights reserved

14 CFR 101.21 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.21 Applicability. (a) This subpart applies to operating unmanned rockets. However, a person operating an unmanned rocket within a restricted area must comply with § 101.25(b)(7)(ii) and with any...

14 CFR 101.21 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.21 Applicability. (a) This subpart applies to operating unmanned rockets. However, a person operating an unmanned rocket within a restricted area must comply with § 101.25(b)(7)(ii) and with any...

14 CFR 101.21 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.21 Applicability. (a) This subpart applies to operating unmanned rockets. However, a person operating an unmanned rocket within a restricted area must comply with § 101.25(b)(7)(ii) and with any...

14 CFR 101.21 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.21 Applicability. (a) This subpart applies to operating unmanned rockets. However, a person operating an unmanned rocket within a restricted area must comply with § 101.25(b)(7)(ii) and with any...

14 CFR 101.21 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.21 Applicability. (a) This subpart applies to operating unmanned rockets. However, a person operating an unmanned rocket within a restricted area must comply with § 101.25(b)(7)(ii) and with any...

Wind Generation Feasibility Study in Bethel, AK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tom Humphrey, YKHC; Lance Kincaid, EMCOR Energy & Technologies

2004-07-31

This report studies the wind resources in the Yukon-Kuskokwim Health Corporation (YKHC) region, located in southwestern Alaska, and the applicability of wind generation technologies to YKHC facilities.

Wind Power Generation Design Considerations.

DTIC Science & Technology

1984-12-01

DISTRIBUTION 4 I o ....................................... . . . e . * * TABLES Number Page I Wind Turbine Characteristics II 0- 2 Maximum Economic Life II 3...Ratio of Blade Tip Speed to Wind Speed 10 4 Interference with Microwave and TV Reception by Wind Turbines 13 5 Typical Flow Patterns Over Two...18 * 12 Annual Mean Wind Power Density 21 5 FIGURES (Cont’d) Number Page 13 Wind - Turbine /Generator Types Currently Being Tested on Utility Sites 22 14

Kaman 40 kW wind turbine generator - control system dynamics

NASA Technical Reports Server (NTRS)

Perley, R.

1981-01-01

The generator design incorporates an induction generator for application where a utility line is present and a synchronous generator for standalone applications. A combination of feed forward and feedback control is used to achieve synchronous speed prior to connecting the generator to the load, and to control the power level once the generator is connected. The dynamics of the drive train affect several aspects of the system operation. These were analyzed to arrive at the required shaft stiffness. The rotor parameters that affect the stability of the feedback control loop vary considerably over the wind speed range encountered. Therefore, the controller gain was made a function of wind speed in order to maintain consistent operation over the whole wind speed range. The velocity requirement for the pitch control mechanism is related to the nature of the wind gusts to be encountered, the dynamics of the system, and the acceptable power fluctuations and generator dropout rate. A model was developed that allows the probable dropout rate to be determined from a statistical model of wind gusts and the various system parameters, including the acceptable power fluctuation.

Utility experience with two demonstration wind turbine generators

NASA Astrophysics Data System (ADS)

Wehrey, M. C.

Edison has committed 360 MW of nameplate generating capacity to wind energy by year 1990 in its long-range generation plan. To reach this goal the Company's wind energy program focuses on three areas: the continuous evaluation of the wind resource, the hands-on demonstration of wind turbine generators (WTG) and an association with wind park developers. Two demonstration WTGs have been installed and operated at Edison's Wind Energy Center near Palm Springs, California: a 3 MW horizontal axis Bendix/Schachle WTG and a 500 kW vertical axis Alcoa WTG. They are part of a one to two year test program during which the performance of the WTGs will be evaluated, their system operation and environmental impact will be assessed and the design criteria of future WTGs will be identified. Edison's experience with these two WTGs is summarized and the problems encountered with the operation of the two machines are discussed.

Stability Augmentation of Wind Farm using Variable Speed Permanent Magnet Synchronous Generator

NASA Astrophysics Data System (ADS)

Rosyadi, Marwan; Muyeen, S. M.; Takahashi, Rion; Tamura, Junji

This paper presents a new control strategy of variable speed permanent magnet wind generator for stability augmentation of wind farm including fixed speed wind turbine with Induction Generator (IG). A new control scheme is developed for two levels back-to-back converters of Permanent Magnet Synchronous Generator (PMSG), by which both active and reactive powers delivered to the grid can be controlled easily. To avoid the converter damage, the DC link protection controller is also proposed in order to protect the dc link circuit during fault condition. To evaluate the control capability of the proposed controllers, simulations are performed on two model systems composed of wind farms connected to an infinite bus. From transient and steady state analyses by using PSCAD/EMTDC, it is concluded that the proposed control scheme is very effective to improve the stability of wind farm for severe network disturbance and randomly fluctuating wind speed.

Utility experience with two demonstration wind turbine generators

NASA Technical Reports Server (NTRS)

Wehrey, M. C.

1982-01-01

Edison has committed 360 MW of nameplate generating capacity to wind energy by year 1990 in its long-range generation plan. To reach this goal the Company's wind energy program focuses on three areas: the continuous evaluation of the wind resource, the hands-on demonstration of wind turbine generators (WTG) and an association with wind park developers. Two demonstration WTGs have been installed and operated at Edison's Wind Energy Center near Palm Springs, California: a 3 MW horizontal axis Bendix/Schachle WTG and a 500 kW vertical axis Alcoa WTG. They are part of a one to two year test program during which the performance of the WTGs will be evaluated, their system operation and environmental impact will be assessed and the design criteria of future WTGs will be identified. Edison's experience with these two WTGs is summarized and the problems encountered with the operation of the two machines are discussed.

Asynchrony of wind and hydropower resources in Australia.

PubMed

Gunturu, Udaya Bhaskar; Hallgren, Willow

2017-08-18

Wind and hydropower together constitute nearly 80% of the renewable capacity in Australia and their resources are collocated. We show that wind and hydro generation capacity factors covary negatively at the interannual time scales. Thus, the technology diversity mitigates the variability of renewable power generation at the interannual scales. The asynchrony of wind and hydropower resources is explained by the differential impact of the two modes of the El Ni˜no Southern Oscillation - canonical and Modoki - on the wind and hydro resources. Also, the Modoki El Ni˜no and the Modoki La Ni˜na phases have greater impact. The seasonal impact patterns corroborate these results. As the proportion of wind power increases in Australia's energy mix, this negative covariation has implications for storage capacity of excess wind generation at short time scales and for generation system adequacy at the longer time scales.

Generating Variable Wind Profiles and Modeling Their Effects on Small-Arms Trajectories

DTIC Science & Technology

2016-04-01

ARL-TR-7642 ● APR 2016 US Army Research Laboratory Generating Variable Wind Profiles and Modeling Their Effects on Small-Arms... Wind Profiles and Modeling Their Effects on Small-Arms Trajectories by Timothy A Fargus Weapons and Materials Research Directorate, ARL...Generating Variable Wind Profiles and Modeling Their Effects on Small-Arms Trajectories 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Jie; Jain, Rishabh; Hodge, Bri-Mathias

A data-driven methodology is developed to analyze how ambient and wake turbulence affect the power generation of wind turbine(s). Using supervisory control and data acquisition (SCADA) data from a wind plant, we select two sets of wind velocity and power data for turbines on the edge of the plant that resemble (i) an out-of-wake scenario and (ii) an in-wake scenario. For each set of data, two surrogate models are developed to represent the turbine(s) power generation as a function of (i) the wind speed and (ii) the wind speed and turbulence intensity. Three types of uncertainties in turbine(s) power generationmore » are investigated: (i) the uncertainty in power generation with respect to the reported power curve; (ii) the uncertainty in power generation with respect to the estimated power response that accounts for only mean wind speed; and (iii) the uncertainty in power generation with respect to the estimated power response that accounts for both mean wind speed and turbulence intensity. Results show that (i) the turbine(s) generally produce more power under the in-wake scenario than under the out-of-wake scenario with the same wind speed; and (ii) there is relatively more uncertainty in the power generation under the in-wake scenario than under the out-of-wake scenario.« less

Simulation studies of multiple large wind turbine generators on a utility network

NASA Technical Reports Server (NTRS)

Gilbert, L. J.; Triezenberg, D. M.

1979-01-01

The potential electrical problems that may be inherent in the inertia of clusters of wind turbine generators and an electric utility network were investigated. Preliminary and limited results of an analog simulation of two MOD-2 wind generators tied to an infinite bus indicate little interaction between the generators and between the generators and the bus. The system demonstrated transient stability for the conditions considered.

Renewable energy and sustainable communities: Alaska's wind generator experience.

PubMed

Konkel, R Steven

2013-01-01

In 1984, the Alaska Department of Commerce and Economic Development (DCED) issued the State's first inventory/economic assessment of wind generators, documenting installed wind generator capacity and the economics of replacing diesel-fuel-generated electricity. Alaska's wind generation capacity had grown from hundreds of installed kilowatts to over 15.3 megawatts (MW) by January 2012. This article reviews data and conclusions presented in "Alaska's Wind Energy Systems; Inventory and Economic Assessment" (1). (Alaska Department of Commerce and Economic Development, S. Konkel, 1984). It provides a foundation and baseline for understanding the development of this renewable energy source. Today's technologies have evolved at an astonishing pace; a typical generator in an Alaska wind farm now is likely rated at 1.5-MW capacity, compared to the single-kilowatt (kW) machines present in 1984. Installed capacity has mushroomed, illustrated by Unalakleet's 600-kW wind farm dwarfing the original three 10-kW machines included in the 1984 inventory. Kodiak Electric had three 1.5-MW turbines installed at Pillar Mountain in 2009, with three additional turbines of 4.5-MW capacity installed in 2012. Utilities now actively plan for wind generation and compete for state funding. State of Alaska energy policy provides the context for energy project decision-making. Substantial renewable energy fund (REF) awards--$202,000,000 to date for 227 REF projects in the first 5 cycles of funding--along with numerous energy conservation programs--are now in place. Increasing investment in wind is driven by multiple factors. Stakeholders have interests both in public policy and meeting private investment objectives. Wind generator investors should consider project economics and potential impacts of energy decisions on human health. Specifically this article considers: changing environmental conditions in remote Alaska villages, impacts associated with climate change on human health, progress in better understanding wind energy potential through resource assessments and new tools for detailed feasibility and project planning, need for comprehensive monitoring and data analysis, and state funding requirements and opportunity costs. The energy policy choices ahead for Alaska will have important implications for Arctic population health, especially for those villages whose relatively small size and remote locations make energy a key component of subsistence lifestyles and community sustainability. Wind generation can contribute to meeting renewable energy goals and is a particularly important resource for rural and remote Alaskan communities currently dependent on diesel fuel for generating electricity and heat.

Smoothing Control of Wind Farm Output by Using Kinetic Energy of Variable Speed Wind Power Generators

NASA Astrophysics Data System (ADS)

Sato, Daiki; Saitoh, Hiroumi

This paper proposes a new control method for reducing fluctuation of power system frequency through smoothing active power output of wind farm. The proposal is based on the modulation of rotaional kinetic energy of variable speed wind power generators through power converters between permanent magnet synchronous generators (PMSG) and transmission lines. In this paper, the proposed control is called Fluctuation Absorption by Flywheel Characteristics control (FAFC). The FAFC can be easily implemented by adding wind farm output signal to Maximum Power Point Tracking control signal through a feedback control loop. In order to verify the effectiveness of the FAFC control, a simulation study was carried out. In the study, it was assumed that the wind farm consisting of PMSG type wind power generator and induction machine type wind power generaotors is connected with a power sysem. The results of the study show that the FAFC control is a useful method for reducing the impacts of wind farm output fluctuation on system frequency without additional devices such as secondary battery.

Assessment of Wind Resource in the Palk Strait using Different Methods

NASA Astrophysics Data System (ADS)

Gupta, T.; Khan, F.; Baidya Roy, S.; Miller, L.

2017-12-01

The Government of India has proposed a target of 60 GW in grid power from the wind by the year 2022. The Palk Strait is one of the potential offshore wind power generation sites in India. It is a 65-135 km wide and 135 km long channel lying between the south eastern tip of India and northern Sri Lanka. The complex terrain bounding the two sides of the strait leads to enhanced wind speed and reduced variability in the wind direction. Here, we compare 3 distinct methodologies for estimating the generation rates for a hypothetical offshore wind farm array located in the strait. The methodologies include: 1) traditional wind power density model that ignores the effect of turbine interactions on generation rates; 2) the PARK wake model; and 3) a high resolution weather model (WRF) with a wind turbine parameterization. Using the WRF model as our baseline, we find that the simple model overestimates generation by an order-of-magnitude, while the wake model underestimates generation rates by about 5%. The reason for these differences relates to the influence of wind turbines on the atmospheric flow, wherein, the WRF model is able to capture the effect of both the complex terrain and wind turbine atmospheric boundary layer interactions. Lastly, a model evaluation is conducted which shows that 10m wind speeds and directions from WRF are comparable with the satellite data. Hence, we conclude from the study that each of these methodologies may have merit, but should a wind farm is deployed in such a complex terrain, we expect the WRF method to give better estimates of wind resource assessment capturing the physical processes emerging due to the interactions between offshore wind farm and the surrounding terrain.

Design and aero-acoustic analysis of a counter-rotating wind turbine

NASA Astrophysics Data System (ADS)

Agrawal, Vineesh V.

Wind turbines have become an integral part of the energy business because they are one of the most economical and reliable sources of renewable energy. Conventional wind turbines are capable of capturing less than half of the energy present in the wind. Hence, to make the wind turbines more efficient, it is important to increase their performance. A horizontal axis wind turbine with multiple rotors is one concept that can achieve a higher power conversion rate. Also, a concern for wind energy is the noise generated by wind turbines. Hence, an investigation into the acoustic behavior of a multi-rotor horizontal axis wind turbine is required. In response to the need of a wind turbine design with higher power coefficient, a unique design of a counter-rotating horizontal axis wind turbine (CR-HAWT) is proposed. The Blade Element Momentum (BEM) theory is used to aerodynamically design the blades of the two rotors. Modifications are made to the BEM theory to accommodate the interaction of the two rotors. The tower effect on the noise generation of the downwind rotor is investigated. Predictions are made for the total noise generated by the wind turbine at its design operating conditions. A total power coefficient of 65.2% is predicted for the proposed CR-HAWT design. A low tip speed ratio is chosen to minimize the noise generation. The aeroacoustic analysis of the CR-HAWT shows that the noise generated at its design operating conditions is within an acceptable range. Thus, the CR-HAWT is predicted to be a quiet wind turbine with a high power coefficient, making it highly desirable for small wind turbine applications.

Empirical Analysis of the Variability of Wind Generation in India: Implications for Grid Integration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phadke, Amol; Abhyankar, NIkit; Rao, Poorvi

We analyze variability in load and wind generation in India to assess its implications for grid integration of large scale wind projects using actual wind generation and load data from two states in India, Karnataka and Tamil Nadu. We compare the largest variations in load and net load (load ?wind, i.e., load after integrating wind) that the generation fleet has to meet. In Tamil Nadu, where wind capacity is about 53percent of the peak demand, we find that the additional variation added due to wind over the current variation in load is modest; if wind penetration reaches 15percent and 30percentmore » by energy, the additional hourly variation is less than 0.5percent and 4.5percent of the peak demand respectively for 99percent of the time. For wind penetration of 15percent by energy, Tamil Nadu system is found to be capable of meeting the additional ramping requirement for 98.8percent of the time. Potential higher uncertainty in net load compared to load is found to have limited impact on ramping capability requirements of the system if coal plants can me ramped down to 50percent of their capacity. Load and wind aggregation in Tamil Nadu and Karnataka is found to lower the variation by at least 20percent indicating the benefits geographic diversification. These findings suggest modest additional flexible capacity requirements and costs for absorbing variation in wind power and indicate that the potential capacity support (if wind does not generate enough during peak periods) may be the issue that has more bearing on the economics of integrating wind« less

Lessons from wind policy in Portugal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peña, Ivonne; L. Azevedo, Inês; Marcelino Ferreira, Luís António Fialho

Wind capacity and generation grew rapidly in several European countries, such as Portugal. Wind power adoption in Portugal began in the early 2000s, incentivized by a continuous feed-in tariff policy mechanism, coupled with public tenders for connection licenses in 2001, 2002, and 2005. These policies led to an enormous success in terms of having a large share of renewables providing electricity services: wind alone accounts today for ~23.5% of electricity demand in Portugal. We explain the reasons wind power became a key part of Portugal's strategy to comply with European Commission climate and energy goals, and provide a detailed reviewmore » of the wind feed-in tariff mechanism. We describe the actors involved in wind power production growth. We estimate the environmental and energy dependency gains achieved through wind power generation, and highlight the correlation between wind electricity generation and electricity exports. Finally, we compare the Portuguese wind policies with others countries' policy designs and discuss the relevance of a feed-in tariff reform for subsequent wind power additions.« less

Discussion on mass concrete construction of wind turbine generator foundation

NASA Astrophysics Data System (ADS)

Shang, Liang; Wu, Chaoxiang; Yin, Xiaoyong

2018-04-01

Wind power is one of the main power sources currently. China has rich wind power resources, wind power plants are developed faster and faster. However, China wind power construction started late, which is lack of relevant experience technology. It is easy to produce quality problems. The key to the construction quality of wind power plant is the construction quality of mass concrete construction. Therefore, construction technology and quality control of wind turbine generator foundation mass concrete are discussed and analyzed in the paper.

Wind Energy Resource Atlas of the Dominican Republic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elliott, D.; Schwartz, M.; George, R.

2001-10-01

The Wind Energy Resource Atlas of the Dominican Republic identifies the wind characteristics and the distribution of the wind resource in this country. This major project is the first of its kind undertaken for the Dominican Republic. The information contained in the atlas is necessary to facilitate the use of wind energy technologies, both for utility-scale power generation and off-grid wind energy applications. A computerized wind mapping system developed by NREL generated detailed wind resource maps for the entire country. This technique uses Geographic Information Systems (GIS) to produce high-resolution (1-square kilometer) annual average wind resource maps.

Economically Feasible Potentials for Wind Power in China and the US

NASA Astrophysics Data System (ADS)

Lu, X.; McElroy, M. B.; Chris, N. P.; Tchou, J.

2011-12-01

The present study is intended to explore the economic feasible potentials for wind energy in China and the U.S. subject to their policy systems for renewable energy. These two countries were chosen as subject locales for three reasons: first, they are the two largest countries responsible for energy consumption and CO2 emissions; second, these two countries have the largest installed capacities and the fastest annual growth of wind power in the world; third, China and the U.S. have adopted two distinct but representative incentive policies to accelerate exploitation of the renewable energy source from wind. Investments in large-scale wind farms in China gain privileges from the concession policy established under China's Renewable Energy Law. The electricity generated from wind can be sold at a guaranteed price for a concession period (typically the first ten operational years of a wind farm) to ensure the profitability of the wind farm development. The effectiveness of this policy has been evidenced by the swift growth of total installed capacities for wind power over the past five years in China. A spatial financial model was developed to evaluate the bus-bar prices of wind-generated electricity in China following this wind concession policy. The results indicated that wind could accommodate all of the demand for electricity projected for 2030 assuming a guaranteed bus-bar price of 7.6 U.S. Cents per kWh over the concession period. It is noteworthy that the prices of wind-generated electricity could be as cheap as conventional power generation in the years following the concession period. The power market in the U.S. is more deregulated and electricity is normally traded in a bidding process an hour to a day ahead of real time. Accordingly, the market-oriented policy instrument of PTC subsidies was instituted in the U.S. to ensure the competitiveness of wind power compared to the conventional power generation in the regional power markets. The spatial financial model developed for previous analysis of wind energy in China was tailored to simulate the relevant investment environments for U.S. wind projects. A particular problem was investigated as to how the profitability and competitiveness of onshore wind power in the U.S. would be influenced by PTC subsidy levels varying from 0 to 4 cents per kWh. The results suggested that the current PTC level (2.1 cent per kWh) is at a critical point in determining the competitiveness of wind-generated electricity under normal costs. Setting system integration challenges aside, the potential for profitable wind-generated electricity could accommodate more than seven times U.S. electricity demand at the current PTC subsidy. Similar to the concession policy adopted in China, PTC subsidies are only available for the first ten years following the initiation of wind farms; wind power would still offer a renewable energy source for profitable electricity generation during the post-PTC period.

Dynamics and stability of wind turbine generators

NASA Technical Reports Server (NTRS)

Hinrichsen, E. N.; Nolan, P. J.

1981-01-01

Synchronous and induction generators are considered. A comparison is made between wind turbines, steam, and hydro units. The unusual phenomena associated with wind turbines are emphasized. The general control requirements are discussed, as well as various schemes for torsional damping such as speed sensitive stabilizer and blade pitch control. Integration between adjacent wind turbines in a wind farm is also considered.

75 FR 11530 - Crystal Lake Wind III, LLC, et al.; Notice of Effectiveness of Exempt Wholesale Generator Status

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-11

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Crystal Lake Wind III, LLC, et al.; Notice of Effectiveness of Exempt Wholesale Generator Status March 4, 2010. Docket Nos. Crystal Lake Wind III, LLC EG10-6-000 GardenGarden Wind, LLC EG10-7-000 Star Point Wind Project LLC EG10-8-000...

77 FR 20378 - Combined Notice of Filings #2

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-04

... Generator Status of Ensign Wind, LLC. Filed Date: 3/27/12. Accession Number: 20120327-5056. Comments Due: 5... of Self-Certification of Exempt Wholesale Generator Status of Tuscola Bay Wind, LLC. Filed Date: 3/27.... Applicants: Minco Wind III, LLC. Description: Notice of Self-Certification of Exempt Wholesale Generator...

Assessing the Structural, Driver and Economic Impacts of Traffic Pole Mounted Wind Power Generator and Solar Panel Hybrid System

DOT National Transportation Integrated Search

2012-06-01

This project evaluates the physical and economic feasibility of using existing traffic infrastructure to mount wind power : generators. Some possible places to mount a light weight wind generator and solar panel hybrid system are: i) Traffic : signal...

75 FR 74042 - Intent To Prepare an Environmental Impact Statement and To Conduct Scoping Meetings...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-30

... proposed Project would consist of up to 100 wind turbine generators with a combined total generating... its wind generation turbines and related facilities. Available overview information indicates this... process for the wind turbine strings and associated facilities considered sensitive resources, and the...

Simulation and study of power quality issues in a fixed speed wind farm substation.

PubMed

Magesh, T; Chellamuthu, C

2015-01-01

Power quality issues associated with the fixed speed wind farm substation located at Coimbatore district are investigated as the wind generators are tripping frequently. The investigations are carried out using two power quality analyzers, Fluke 435 and Dranetz PX5.8, with one of them connected at group control breaker of the 110 kV feeder and the other at the selected 0.69 kV generator busbar during the period of maximum power generation. From the analysis of the recorded data it is found that sag, swell, and transients are the major events which are responsible for the tripping of the generators. In the present study, simulation models for wind, turbine, shaft, pitch mechanism, induction generator, and grid are developed using DIgSILENT. Using the turbine characteristics, a two-dimensional lookup table is designed to generate a reference pitch angle necessary to simulate the power curve of the passive stall controlled wind turbine. Various scenarios and their effects on the performance of the wind farm are studied and validated with the recorded data and waveforms. The simulation model will be useful for the designers for planning and development of the wind farm before implementation.

Simulation and Study of Power Quality Issues in a Fixed Speed Wind Farm Substation

PubMed Central

Magesh, T.; Chellamuthu, C.

2015-01-01

Power quality issues associated with the fixed speed wind farm substation located at Coimbatore district are investigated as the wind generators are tripping frequently. The investigations are carried out using two power quality analyzers, Fluke 435 and Dranetz PX5.8, with one of them connected at group control breaker of the 110 kV feeder and the other at the selected 0.69 kV generator busbar during the period of maximum power generation. From the analysis of the recorded data it is found that sag, swell, and transients are the major events which are responsible for the tripping of the generators. In the present study, simulation models for wind, turbine, shaft, pitch mechanism, induction generator, and grid are developed using DIgSILENT. Using the turbine characteristics, a two-dimensional lookup table is designed to generate a reference pitch angle necessary to simulate the power curve of the passive stall controlled wind turbine. Various scenarios and their effects on the performance of the wind farm are studied and validated with the recorded data and waveforms. The simulation model will be useful for the designers for planning and development of the wind farm before implementation. PMID:25950016

On the Role of Interchange Reconnection in the Generation of the Slow Solar Wind

NASA Astrophysics Data System (ADS)

Edmondson, J. K.

2012-11-01

The heating of the solar corona and therefore the generation of the solar wind, remain an active area of solar and heliophysics research. Several decades of in situ solar wind plasma observations have revealed a rich bimodal solar wind structure, well correlated with coronal magnetic field activity. Therefore, the reconnection processes associated with the large-scale dynamics of the corona likely play a major role in the generation of the slow solar wind flow regime. In order to elucidate the relationship between reconnection-driven coronal magnetic field structure and dynamics and the generation of the slow solar wind, this paper reviews the observations and phenomenology of the solar wind and coronal magnetic field structure. The geometry and topology of nested flux systems, and the (interchange) reconnection process, in the context of coronal physics is then explained. Once these foundations are laid out, the paper summarizes several fully dynamic, 3D MHD calculations of the global coronal system. Finally, the results of these calculations justify a number of important implications and conclusions on the role of reconnection in the structural dynamics of the coronal magnetic field and the generation of the solar wind.

Power control and management of the grid containing largescale wind power systems

NASA Astrophysics Data System (ADS)

Aula, Fadhil Toufick

The ever increasing demand for electricity has driven many countries toward the installation of new generation facilities. However, concerns such as environmental pollution and global warming issues, clean energy sources, high costs associated with installation of new conventional power plants, and fossil fuels depletion have created many interests in finding alternatives to conventional fossil fuels for generating electricity. Wind energy is one of the most rapidly growing renewable power sources and wind power generations have been increasingly demanded as an alternative to the conventional fossil fuels. However, wind power fluctuates due to variation of wind speed. Therefore, large-scale integration of wind energy conversion systems is a threat to the stability and reliability of utility grids containing these systems. They disturb the balance between power generation and consumption, affect the quality of the electricity, and complicate load sharing and load distribution managing and planning. Overall, wind power systems do not help in providing any services such as operating and regulating reserves to the power grid. In order to resolve these issues, research has been conducted in utilizing weather forecasting data to improve the performance of the wind power system, reduce the influence of the fluctuations, and plan power management of the grid containing large-scale wind power systems which consist of doubly-fed induction generator based energy conversion system. The aims of this research, my dissertation, are to provide new methods for: smoothing the output power of the wind power systems and reducing the influence of their fluctuations, power managing and planning of a grid containing these systems and other conventional power plants, and providing a new structure of implementing of latest microprocessor technology for controlling and managing the operation of the wind power system. In this research, in order to reduce and smooth the fluctuations, two methods are presented. The first method is based on a de-loaded technique while the other method is based on utilizing multiple storage facilities. The de-loaded technique is based on characteristics of the power of a wind turbine and estimation of the generated power according to weather forecasting data. The technique provides a reference power by which the wind power system will operate and generate a smooth power. In contrast, utilizing storage facilities will allow the wind power system to operate at its maximum tracking power points' strategy. Two types of energy storages are considered in this research, battery energy storage system (BESS) and pumped-hydropower storage system (PHSS), to suppress the output fluctuations and to support the wind power system to follow the system load demands. Furthermore, this method provides the ability to store energy when there is a surplus of the generated power and to reuse it when there is a shortage of power generation from wind power systems. Both methods are new in terms of utilizing of the techniques and wind speed data. A microprocessor embedded system using an IntelRTM Atom(TM) processor is presented for controlling the wind power system and for providing the remote communication for enhancing the operation of the individual wind power system in a wind farm. The embedded system helps the wind power system to respond and to follow the commands of the central control of the power system. Moreover, it enhances the performance of the wind power system through self-managing, self-functioning, and self-correcting. Finally, a method of system power management and planning is modeled and studied for a grid containing large-scale wind power systems. The method is based on a new technique through constructing a new load demand curve (NLDC) from merging the estimation of generated power from wind power systems and forecasting of the load. To summarize, the methods and their results presented in this dissertation, enhance the operation of the large-scale wind power systems and reduce their drawbacks on the operation of the power grid.

Dual stator winding variable speed asynchronous generator: optimal design and experiments

NASA Astrophysics Data System (ADS)

Tutelea, L. N.; Deaconu, S. I.; Popa, G. N.

2015-06-01

In the present paper is carried out a theoretical and experimental study of dual stator winding squirrel cage asynchronous generator (DSWA) behavior in the presence of saturation regime (non-sinusoidal) due to the variable speed operation. The main aims are the determination of the relations of calculating the equivalent parameters of the machine windings to optimal design using a Matlab code. Issue is limited to three phase range of double stator winding cage-induction generator of small sized powers, the most currently used in the small adjustable speed wind or hydro power plants. The tests were carried out using three-phase asynchronous generator having rated power of 6 [kVA].

Design, manufacturing and tests of first cryogen-free MgB2 prototype coils for offshore wind generators

NASA Astrophysics Data System (ADS)

Sarmiento, G.; Sanz, S.; Pujana, A.; Merino, J. M.; Iturbe, R.; Apiñaniz, S.; Nardelli, D.; Marino, I.

2014-05-01

Although renewable sector has started to take advantage of the offshore wind energy recently, the development is very intense. Turbines reliability, size, and cost are key aspects for the wind industry, especially in marine locations. A superconducting generator will allow a significant reduction in terms of weight and size, but cost and reliability are two aspects to deal with. MgB2 wire is presented as one promising option to be used in superconducting coils for wind generators. This work shows the experimental results in first cryogen-free MgB2 prototype coils, designed according to specific requirements of TECNALIA's wind generator concept.

Effect of Dimension and Shape of Magnet on the Performance AC Generator with Translation Motion

NASA Astrophysics Data System (ADS)

Indriani, A.; Dimas, S.; Hendra

2018-02-01

The development of power plants using the renewable energy sources is very rapid. Renewable energy sources used solar energy, wind energy, ocean wave energy and other energy. All of these renewable energy sources require a processing device or a change of motion system to become electrical energy. One processing device is a generator which have work principle of converting motion (mechanical) energy into electrical energy with rotary shaft, blade and other motion components. Generator consists of several types of rotation motion and linear motion (translational). The generator have components such as rotor, stator and anchor. In the rotor and stator having magnet and winding coil as an electric generating part of the electric motion force. Working principle of AC generator with linear motion (translation) also apply the principle of Faraday that is using magnetic induction which change iron magnet to produce magnetic flux. Magnetic flux is captured by the stator to be converted into electrical energy. Linear motion generators consist of linear induction machine, wound synchronous machine field, and permanent magnet synchronous [1]. Performance of synchronous generator of translation motion is influenced by magnet type, magnetic shape, coil winding, magnetic and coil spacing and others. In this paper focus on the neodymium magnet with varying shapes, number of coil windings and gap of magnetic distances. This generator work by using pneumatic mechanism (PLTGL) for power plants system. Result testing of performance AC generator translation motion obtained that maximum voltage, current and power are 63 Volt for diameter winding coil 0.15 mm, number of winding coil 13000 and distance of magnet 20 mm. For effect shape of magnet, maximum voltage happen on rectangle magnet 30x20x5 mm with 4.64 Volt. Voltage and power on effect of diameter winding coil is 14.63 V and 17.82 W at the diameter winding coil 0.7 and number of winding coil is 1260 with the distance of magnet 25 mm.

Variable Frequency Operations of an Offshore Wind Power Plant with HVDC-VSC: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

2011-12-01

In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated. Based on DOE study, wind power generation may reach 330 GW by 2030 at the level of penetration of 20% of the total energy production. From this amount of wind power, 54 GW of wind power will be generated at offshore wind power plants. The deployment of offshore wind power plants requires power transmission from the plant to the load center inland. Since this power transmissionmore » requires submarine cable, there is a need to use High-Voltage Direct Current (HVDC) transmission. Otherwise, if the power is transmitted via alternating current, the reactive power generated by the cable capacitance may cause an excessive over voltage in the middle of the transmission distance which requires unnecessary oversized cable voltage breakdown capability. The use of HVDC is usually required for transmission distance longer than 50 kilometers of submarine cables to be economical. The use of HVDC brings another advantage; it is capable of operating at variable frequency. The inland substation will be operated to 60 Hz synched with the grid, the offshore substation can be operated at variable frequency, thus allowing the wind power plant to be operated at constant Volt/Hz. In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated.« less

A study on the required performance of a 2G HTS wire for HTS wind power generators

NASA Astrophysics Data System (ADS)

Sung, Hae-Jin; Park, Minwon; Go, Byeong-Soo; Yu, In-Keun

2016-05-01

YBCO or REBCO coated conductor (2G) materials are developed for their superior performance at high magnetic field and temperature. Power system applications based on high temperature superconducting (HTS) 2G wire technology are attracting attention, including large-scale wind power generators. In particular, to solve problems associated with the foundations and mechanical structure of offshore wind turbines, due to the large diameter and heavy weight of the generator, an HTS generator is suggested as one of the key technologies. Many researchers have tried to develop feasible large-scale HTS wind power generator technologies. In this paper, a study on the required performance of a 2G HTS wire for large-scale wind power generators is discussed. A 12 MW class large-scale wind turbine and an HTS generator are designed using 2G HTS wire. The total length of the 2G HTS wire for the 12 MW HTS generator is estimated, and the essential prerequisites of the 2G HTS wire based generator are described. The magnetic field distributions of a pole module are illustrated, and the mechanical stress and strain of the pole module are analysed. Finally, a reasonable price for 2G HTS wire for commercialization of the HTS generator is suggested, reflecting the results of electromagnetic and mechanical analyses of the generator.

Transient Stability of the US Western Interconnection with High Wind and Solar Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, Kara; Miller, Nicholas W.; Shao, Miaolei

The addition of large amounts of wind and solar generation to bulk power systems that are traditionally subject to operating constraints set by transient limitations is the subject of considerable concern in the industry. The US Western Interconnection (WI) is expected to experience substantial additional growth in both wind and solar generation. These plants will, to some extent, displace large central station thermal generation, both coal and gas-fired, which have traditionally helped maintain stability. This paper reports the results of a study that investigated the transient stability of the WI with high penetrations of wind and solar generation. The mainmore » goals of this work were to (1) create a realistic, baseline model of the WI, (2) test selected transient stability events, (3) investigate the impact of large amounts of wind and solar generation, and (4) examine means to improve performance.« less

Air: Simple Experiments for Young Scientists.

ERIC Educational Resources Information Center

White, Larry

This book contains simple experiments through which students explore air and its properties. Some of the topics discussed include alternative energy, bacteria, carbon dioxide, motion, weather, and flight. Experiments include: blowing a balloon up in a bottle; seeing air in water; making a lunch-bag kite, weather vanes, and paper glider;…

Award-Winning Books: A Selected List for Teens.

ERIC Educational Resources Information Center

Dayton, Sandra

1984-01-01

Lists adolescent fiction and nonfiction titles that received Boston Globe/Horn Book Award, Carnegie Medal, Child Study Children's Book Committee at Bank Street College Award, Christopher Award, Edgar Allen Poe Award, Golden Kite Award, Nebula Award, and National Book Award/American Book Award. Each entry includes bibliographic information and…

14 CFR 101.22 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.22 Definitions. The following definitions apply to this subpart: (a) Class 1—Model Rocket means an amateur rocket that: (1) Uses no more than 125 grams (4.4 ounces) of propellant; (2) Uses a...

14 CFR 101.22 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.22 Definitions. The following definitions apply to this subpart: (a) Class 1—Model Rocket means an amateur rocket that: (1) Uses no more than 125 grams (4.4 ounces) of propellant; (2) Uses a...

14 CFR 101.22 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.22 Definitions. The following definitions apply to this subpart: (a) Class 1—Model Rocket means an amateur rocket that: (1) Uses no more than 125 grams (4.4 ounces) of propellant; (2) Uses a...

14 CFR 101.22 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.22 Definitions. The following definitions apply to this subpart: (a) Class 1—Model Rocket means an amateur rocket that: (1) Uses no more than 125 grams (4.4 ounces) of propellant; (2) Uses a...

14 CFR 101.22 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.22 Definitions. The following definitions apply to this subpart: (a) Class 1—Model Rocket means an amateur rocket that: (1) Uses no more than 125 grams (4.4 ounces) of propellant; (2) Uses a...

77 FR 46428 - Combined Notice of Filings #2

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-03

... Generator Status of Spinning Spur Wind LLC. Filed Date: 7/27/12. Accession Number: 20120727-5038. Comments... II Wind Farm LLC, Fowler Ridge III Wind Farm LLC, Fowler Ridge Wind Farm LLC, Goshen Phase II, LLC... that the Commission received the following exempt wholesale generator filings: Docket Numbers: EG12-93...

78 FR 9682 - Combined Notice of Filings #2

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-11

... Wholesale Generator Status of Niagara Wind Power, LLC. Filed Date: 1/31/13. Accession Number: 20130131-5139... Bay Wind, LLC, Vasco Winds, LLC, Victory Garden Phase IV, LLC, Waymart Wind Farm, L.P., Wessington... that the Commission received the following exempt wholesale generator filings: Docket Numbers: EG13-15...

Benefit-cost methodology study with example application of the use of wind generators

NASA Technical Reports Server (NTRS)

Zimmer, R. P.; Justus, C. G.; Mason, R. M.; Robinette, S. L.; Sassone, P. G.; Schaffer, W. A.

1975-01-01

An example application for cost-benefit methodology is presented for the use of wind generators. The approach adopted for the example application consisted of the following activities: (1) surveying of the available wind data and wind power system information, (2) developing models which quantitatively described wind distributions, wind power systems, and cost-benefit differences between conventional systems and wind power systems, and (3) applying the cost-benefit methodology to compare a conventional electrical energy generation system with systems which included wind power generators. Wind speed distribution data were obtained from sites throughout the contiguous United States and were used to compute plant factor contours shown on an annual and seasonal basis. Plant factor values (ratio of average output power to rated power) are found to be as high as 0.6 (on an annual average basis) in portions of the central U. S. and in sections of the New England coastal area. Two types of wind power systems were selected for the application of the cost-benefit methodology. A cost-benefit model was designed and implemented on a computer to establish a practical tool for studying the relative costs and benefits of wind power systems under a variety of conditions and to efficiently and effectively perform associated sensitivity analyses.

Wind, Wave, and Tidal Energy Without Power Conditioning

NASA Technical Reports Server (NTRS)

Jones, Jack A.

2013-01-01

Most present wind, wave, and tidal energy systems require expensive power conditioning systems that reduce overall efficiency. This new design eliminates power conditioning all, or nearly all, of the time. Wind, wave, and tidal energy systems can transmit their energy to pumps that send high-pressure fluid to a central power production area. The central power production area can consist of a series of hydraulic generators. The hydraulic generators can be variable displacement generators such that the RPM, and thus the voltage, remains constant, eliminating the need for further power conditioning. A series of wind blades is attached to a series of radial piston pumps, which pump fluid to a series of axial piston motors attached to generators. As the wind is reduced, the amount of energy is reduced, and the number of active hydraulic generators can be reduced to maintain a nearly constant RPM. If the axial piston motors have variable displacement, an exact RPM can be maintained for all, or nearly all, wind speeds. Analyses have been performed that show over 20% performance improvements with this technique over conventional wind turbines

Energy Storage on the Grid and the Short-term Variability of Wind

NASA Astrophysics Data System (ADS)

Hittinger, Eric Stephen

Wind generation presents variability on every time scale, which must be accommodated by the electric grid. Limited quantities of wind power can be successfully integrated by the current generation and demand-side response mix but, as deployment of variable resources increases, the resulting variability becomes increasingly difficult and costly to mitigate. In Chapter 2, we model a co-located power generation/energy storage block composed of wind generation, a gas turbine, and fast-ramping energy storage. A scenario analysis identifies system configurations that can generate power with 30% of energy from wind, a variability of less than 0.5% of the desired power level, and an average cost around $70/MWh. While energy storage technologies have existed for decades, fast-ramping grid-level storage is still an immature industry and is experiencing relatively rapid improvements in performance and cost across a variety of technologies. Decreased capital cost, increased power capability, and increased efficiency all would improve the value of an energy storage technology and each has cost implications that vary by application, but there has not yet been an investigation of the marginal rate of technical substitution between storage properties. The analysis in chapter 3 uses engineering-economic models of four emerging fast-ramping energy storage technologies to determine which storage properties have the greatest effect on cost-of-service. We find that capital cost of storage is consistently important, and identify applications for which power/energy limitations are important. In some systems with a large amount of wind power, the costs of wind integration have become significant and market rules have been slowly changing in order to internalize or control the variability of wind generation. Chapter 4 examines several potential market strategies for mitigating the effects of wind variability and estimate the effect that each strategy would have on the operation and profitability of wind farms. We find that market scenarios using existing price signals to motivate wind to reduce variability allow wind generators to participate in variability reduction when the market conditions are favorable, and can reduce short-term (30-minute) fluctuations while having little effect on wind farm revenue.

Wind energy developments in the 20th century

NASA Technical Reports Server (NTRS)

Vargo, D. J.

1974-01-01

Wind turbine systems for generating electrical power have been tested in many countries. Representative examples of turbines which have produced from 100 to 1250 kW are described. The advantages of wind energy consist of its being a nondepleting, nonpolluting, and free fuel source. Its disadvantages relate to the variability of wind and the high installation cost per kilowatt of capacity of wind turbines when compared to other methods of electric-power generation. High fuel costs and potential resource scarcity have led to a five-year joint NASA-NSF program to study wind energy. The program will study wind energy conversion and storage systems with respect to cost effectiveness, and will attempt to estimate national wind-energy potential and develop techniques for generator site selection. The studies concern a small-systems (50-250 kW) project, a megawatt-systems (500-3000 kW) project, supporting research and technology, and energy storage. Preliminary economic analyses indicate that wind-energy conversion can be competitive in high-average-wind areas.

Wind energy utilization: A bibliography with abstracts - Cumulative volume 1944/1974

NASA Technical Reports Server (NTRS)

1975-01-01

Bibliography, up to 1974 inclusive, of articles and books on utilization of wind power in energy generation. Worldwide literature is surveyed, and short abstracts are provided in many cases. The citations are grouped by subject: (1) general; (2) utilization; (3) wind power plants; (4) wind power generators (rural, synchronous, remote station); (5) wind machines (motors, pumps, turbines, windmills, home-built); (6) wind data and properties; (7) energy storage; and (8) related topics (control and regulation devices, wind measuring devices, blade design and rotors, wind tunnel simulation, aerodynamics). Gross-referencing is aided by indexes of authors, corporate sources, titles, and keywords.

Motion picture history of the erection and operation of the Smith-Putnam wind generator

NASA Technical Reports Server (NTRS)

Wilcox, C.

1973-01-01

A color movie presentation is discussed that presents the various stages in assemblying the major subsystems of a synchronous wind generator, such as installing the rotor blades and the rotating platform at the top of the tower. In addition scenes are shown of the wind generator in operation.

76 FR 23198 - Segregation of Lands-Renewable Energy

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-26

... could be used to carry the power generated from a specific wind or solar energy ROW project, and the... included in a pending or future wind or solar energy generation right- of-way (ROW) application, or public lands identified by the BLM for a potential future wind or solar energy generation ROW authorization...

Wind-Driven Ecological Flow Regimes Downstream from Hydropower Dams

NASA Astrophysics Data System (ADS)

Kern, J.; Characklis, G. W.

2012-12-01

Conventional hydropower can be turned on and off quicker and less expensively than thermal generation (coal, nuclear, or natural gas). These advantages enable hydropower utilities to respond to rapid fluctuations in energy supply and demand. More recently, a growing renewable energy sector has underlined the need for flexible generation capacity that can complement intermittent renewable resources such as wind power. While wind power entails lower variable costs than other types of generation, incorporating it into electric power systems can be problematic. Due to variable and unpredictable wind speeds, wind power is difficult to schedule and must be used when available. As a result, integrating large amounts of wind power into the grid may result in atypical, swiftly changing demand patterns for other forms of generation, placing a premium on sources that can be rapidly ramped up and down. Moreover, uncertainty in wind power forecasts will stipulate increased levels of 'reserve' generation capacity that can respond quickly if real-time wind supply is less than expected. These changes could create new hourly price dynamics for energy and reserves, altering the short-term financial signals that hydroelectric dam operators use to schedule water releases. Traditionally, hourly stream flow patterns below hydropower dams have corresponded in a very predictable manner to electricity demand, whose primary factors are weather (hourly temperature) and economic activity (workday hours). Wind power integration has the potential to yield more variable, less predictable flows at hydro dams, flows that at times could resemble reciprocal wind patterns. An existing body of research explores the impacts of standard, demand-following hydroelectric dams on downstream ecological flows; but weighing the benefits of increased reliance on wind power against further impacts to ecological flows may be a novel challenge for the environmental community. As a preliminary step in meeting this challenge, the following study was designed to investigate the potential for wind power integration to alter riparian flow regimes below hydroelectric dams. A hydrological model of a three-dam cascade in the Roanoke River basin (Virginia, USA) is interfaced with a simulated electricity market (i.e. a unit commitment problem) representing the Dominion Zone of PJM Interconnection. Incorporating forecasts of electricity demand, hydro capacity and wind availability, a mixed-integer optimization program minimizes the system cost of meeting hourly demand and reserve requirements by means of a diverse generation portfolio (e.g. nuclear, fossil, hydro, and biomass). A secondary 'balancing' energy market is executed if real-time wind generation is less than the day-ahead forecast, calling upon reserved generation resources to meet the supply shortfall. Hydropower release schedules are determined across a range of wind development scenarios (varying wind's fraction of total installed generating capacity, as well as its geographical source region). Flow regimes for each wind development scenario are compared against both historical and simulated flows under current operations (negligible wind power), as well as simulated natural flows (dam removal), in terms of ecologically relevant flow metrics. Results quantify the ability of wind power development to alter within-week stream flows downstream from hydropower dams.

Serially-Connected Compensator for Eliminating the Unbalanced Three-Phase Voltage Impact on Wind Turbine Generators: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Z.; Hsu, P.; Muljadi, E.

2015-04-06

Untransposed transmission lines, unbalanced tap changer operations, and unbalanced loading in weak distribution lines can cause unbalanced-voltage conditions. The resulting unbalanced voltage at the point of interconnection affects proper gird integration and reduces the lifetime of wind turbines due to power oscillations, torque pulsations, mechanical stresses, energy losses, and uneven and overheating of the generator stator winding. This work investigates the dynamic impact of unbalanced voltage on the mechanical and electrical components of integrated Fatigue, Aerodynamics, Structures, and Turbulence (FAST) wind turbine generation systems (WTGs) of Type 1 (squirrel-cage induction generator) and Type 3 (doubly-fed induction generator). To alleviate thismore » impact, a serially-connected compensator for a three-phase power line is proposed to balance the wind turbine-side voltage. Dynamic simulation studies are conducted in MATLAB/Simulink to compare the responses of these two types of wind turbine models under normal and unbalanced-voltage operation conditions and demonstrate the effectiveness of the proposed compensator.« less

A Serially-Connected Compensator for Eliminating the Unbalanced Three-Phase Voltage Impact on Wind Turbine Generators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Ziping; Hsu, Ping; Muljadi, Eduard

2015-10-05

Untransposed transmission lines, unbalanced tap changer operations, and unbalanced loading in weak distribution lines can cause unbalanced-voltage conditions. The resulting unbalanced voltage at the point of interconnection affects proper gird integration and reduces the lifetime of wind turbines due to power oscillations, torque pulsations, mechanical stresses, energy losses, and uneven and overheating of the generator stator winding. This work investigates the dynamic impact of unbalanced voltage on the mechanical and electrical components of integrated Fatigue, Aerodynamics, Structures, and Turbulence (FAST) wind turbine generation systems (WTGs) of Type 1 (squirrel-cage induction generator) and Type 3 (doubly-fed induction generator). To alleviate thismore » impact, a serially-connected compensator for a three-phase power line is proposed to balance the wind turbine-side voltage. Dynamic simulation studies are conducted in MATLAB/Simulink to compare the responses of these two types of wind turbine models under normal and unbalanced-voltage operation conditions and demonstrate the effectiveness of the proposed compensator.« less

Energy optimization for a wind DFIG with flywheel energy storage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamzaoui, Ihssen, E-mail: hamzaoui-ihssen2000@yahoo.fr; Laboratory of Instrumentation, Faculty of Electronics and Computer, University of Khemis Miliana, Ain Defla; Bouchafaa, Farid, E-mail: fbouchafa@gmail.com

2016-07-25

The type of distributed generation unit that is the subject of this paper relates to renewable energy sources, especially wind power. The wind generator used is based on a double fed induction Generator (DFIG). The stator of the DFIG is connected directly to the network and the rotor is connected to the network through the power converter with three levels. The objective of this work is to study the association a Flywheel Energy Storage System (FESS) in wind generator. This system is used to improve the quality of electricity provided by wind generator. It is composed of a flywheel; anmore » induction machine (IM) and a power electronic converter. A maximum power tracking technique « Maximum Power Point Tracking » (MPPT) and a strategy for controlling the pitch angle is presented. The model of the complete system is developed in Matlab/Simulink environment / to analyze the results from simulation the integration of wind chain to networks.« less

Research on Operation Strategy for Bundled Wind-thermal Generation Power Systems Based on Two-Stage Optimization Model

NASA Astrophysics Data System (ADS)

Sun, Congcong; Wang, Zhijie; Liu, Sanming; Jiang, Xiuchen; Sheng, Gehao; Liu, Tianyu

2017-05-01

Wind power has the advantages of being clean and non-polluting and the development of bundled wind-thermal generation power systems (BWTGSs) is one of the important means to improve wind power accommodation rate and implement “clean alternative” on generation side. A two-stage optimization strategy for BWTGSs considering wind speed forecasting results and load characteristics is proposed. By taking short-term wind speed forecasting results of generation side and load characteristics of demand side into account, a two-stage optimization model for BWTGSs is formulated. By using the environmental benefit index of BWTGSs as the objective function, supply-demand balance and generator operation as the constraints, the first-stage optimization model is developed with the chance-constrained programming theory. By using the operation cost for BWTGSs as the objective function, the second-stage optimization model is developed with the greedy algorithm. The improved PSO algorithm is employed to solve the model and numerical test verifies the effectiveness of the proposed strategy.

Field-circuit analysis and measurements of a single-phase self-excited induction generator

NASA Astrophysics Data System (ADS)

Makowski, Krzysztof; Leicht, Aleksander

2017-12-01

The paper deals with a single-phase induction machine operating as a stand-alone self-excited single-phase induction generator for generation of electrical energy from renewable energy sources. By changing number of turns and size of wires in the auxiliary stator winding, an improvement of performance characteristics of the generator were obtained as regards no-load and load voltage of the stator windings as well as stator winding currents of the generator. Field-circuit simulation models of the generator were developed using Flux2D software package for the generator with shunt capacitor in the main stator winding. The obtained results have been validated experimentally at the laboratory setup using the single-phase capacitor induction motor of 1.1 kW rated power and 230 V voltage as a base model of the generator.

Control of large wind turbine generators connected to utility networks

NASA Technical Reports Server (NTRS)

Hinrichsen, E. N.

1983-01-01

This is an investigation of the control requirements for variable pitch wind turbine generators connected to electric power systems. The requirements include operation in very small as well as very large power systems. Control systems are developed for wind turbines with synchronous, induction, and doubly fed generators. Simulation results are presented. It is shown how wind turbines and power system controls can be integrated. A clear distinction is made between fast control of turbine torque, which is a peculiarity of wind turbines, and slow control of electric power, which is a traditional power system requirement.

Lewis Research Center studies of multiple large wind turbine generators on a utility network

NASA Technical Reports Server (NTRS)

Gilbert, L. J.; Triezenberg, D. M.

1979-01-01

A NASA-Lewis program to study the anticipated performance of a wind turbine generator farm on an electric utility network is surveyed. The paper describes the approach of the Lewis Wind Energy Project Office to developing analysis capabilities in the area of wind turbine generator-utility network computer simulations. Attention is given to areas such as, the Lewis Purdue hybrid simulation, an independent stability study, DOE multiunit plant study, and the WEST simulator. Also covered are the Lewis mod-2 simulation including analog simulation of a two wind turbine system and comparison with Boeing simulation results, and gust response of a two machine model. Finally future work to be done is noted and it is concluded that the study shows little interaction between the generators and between the generators and the bus.

Long-term variability of wind patterns at hub-height over Texas

NASA Astrophysics Data System (ADS)

Jung, J.; Jeon, W.; Choi, Y.; Souri, A.

2017-12-01

Wind energy is getting more attention because of its environmentally friendly attributes. Texas is a state with significant capacity and number of wind turbines. Wind power generation is significantly affected by wind patterns, and it is important to understand this seasonal and decadal variability for long-term power generation from wind turbines. This study focused on the trends of changes in wind pattern and its strength at two hub-heights (80 m and 110 m) over 30-years (1986 to 2015). We only analyzed summer data(June to September) because of concentrated electricity usage in Texas. We extracted hub-height wind data (U and V components) from the three-hourly National Centers for Environmental Prediction-North American Regional Reanalysis (NCEP-NARR) and classified wind patterns properly by using nonhierarchical K-means method. Hub-height wind patterns in summer seasons of 1986 to 2015 were classified in six classes at day and seven classes at night. Mean wind speed was 4.6 ms-1 at day and 5.4 ms-1 at night, but showed large variability in time and space. We combined each cluster's frequencies and wind speed tendencies with large scale atmospheric circulation features and quantified the amount of wind power generation.

Wind turbine generators having wind assisted cooling systems and cooling methods

DOEpatents

Bagepalli, Bharat [Niskayuna, NY; Barnes, Gary R [Delanson, NY; Gadre, Aniruddha D [Rexford, NY; Jansen, Patrick L [Scotia, NY; Bouchard, Jr., Charles G.; Jarczynski, Emil D [Scotia, NY; Garg, Jivtesh [Cambridge, MA

2008-09-23

A wind generator includes: a nacelle; a hub carried by the nacelle and including at least a pair of wind turbine blades; and an electricity producing generator including a stator and a rotor carried by the nacelle. The rotor is connected to the hub and rotatable in response to wind acting on the blades to rotate the rotor relative to the stator to generate electricity. A cooling system is carried by the nacelle and includes at least one ambient air inlet port opening through a surface of the nacelle downstream of the hub and blades, and a duct for flowing air from the inlet port in a generally upstream direction toward the hub and in cooling relation to the stator.

Capacity Adequacy and Revenue Sufficiency in Electricity Markets With Wind Power

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levin, Todd; Botterud, Audun

2015-05-01

We present a computationally efficient mixed-integer program (MIP) that determines optimal generator expansion decisions, as well as periodic unit commitment and dispatch. The model is applied to analyze the impact of increasing wind power capacity on the optimal generation mix and the profitability of thermal generators. In a case study, we find that increasing wind penetration reduces energy prices while the prices for operating reserves increase. Moreover, scarcity pricing for operating reserves through reserve shortfall penalties significantly impacts the prices and profitability of thermal generators. Without scarcity pricing, no thermal units are profitable, however scarcity pricing can ensure profitability formore » peaking units at high wind penetration levels. Capacity payments can also ensure profitability, but the payments required for baseload units to break even increase with the amount of wind power. The results indicate that baseload units are most likely to experience revenue sufficiency problems when wind penetration increases and new baseload units are only developed when natural gas prices are high and wind penetration is low.« less

Generation of Kappa Distributions in Solar Wind at 1 au

NASA Astrophysics Data System (ADS)

Livadiotis, G.; Desai, M. I.; Wilson, L. B., III

2018-02-01

We examine the generation of kappa distributions in the solar wind plasma near 1 au. Several mechanisms are mentioned in the literature, each characterized by a specific relationship between the solar wind plasma features, the interplanetary magnetic field (IMF), and the kappa index—the parameter that governs the kappa distributions. This relationship serves as a signature condition that helps the identification of the mechanism in the plasma. In general, a mechanism that generates kappa distributions involves a single or a series of stochastic or physical processes that induces local correlations among particles. We identify three fundamental solar wind plasma conditions that can generate kappa distributions, noted as (i) Debye shielding, (ii) frozen IMF, and (iii) temperature fluctuations, each one prevailing in different scales of solar wind plasma and magnetic field properties. Moreover, our findings show that the kappa distributions, and thus, their generating mechanisms, vary significantly with solar wind features: (i) the kappa index has different dependence on the solar wind speed for slow and fast modes, i.e., slow wind is characterized by a quasi-constant kappa index, κ ≈ 4.3 ± 0.7, while fast wind exhibits kappa indices that increase with bulk speed; (ii) the dispersion of magnetosonic waves is more effective for lower kappa indices (i.e., further from thermal equilibrium); and (iii) the kappa and polytropic indices are positively correlated, as it was anticipated by the theory.

Renewable energy and sustainable communities: Alaska's wind generator experience†

PubMed Central

Konkel, R. Steven

2013-01-01

Background In 1984, the Alaska Department of Commerce and Economic Development (DCED) issued the State's first inventory/economic assessment of wind generators, documenting installed wind generator capacity and the economics of replacing diesel-fuel-generated electricity. Alaska's wind generation capacity had grown from hundreds of installed kilowatts to over 15.3 megawatts (MW) by January 2012. Method This article reviews data and conclusions presented in “Alaska's Wind Energy Systems; Inventory and Economic Assessment” (1). (Alaska Department of Commerce and Economic Development, S. Konkel, 1984). It provides a foundation and baseline for understanding the development of this renewable energy source. Results Today's technologies have evolved at an astonishing pace; a typical generator in an Alaska wind farm now is likely rated at 1.5-MW capacity, compared to the single-kilowatt (kW) machines present in 1984. Installed capacity has mushroomed, illustrated by Unalakleet's 600-kW wind farm dwarfing the original three 10-kW machines included in the 1984 inventory. Kodiak Electric had three 1.5-MW turbines installed at Pillar Mountain in 2009, with three additional turbines of 4.5-MW capacity installed in 2012. Utilities now actively plan for wind generation and compete for state funding. Discussion State of Alaska energy policy provides the context for energy project decision-making. Substantial renewable energy fund (REF) awards – $202,000,000 to date for 227 REF projects in the first 5 cycles of funding – along with numerous energy conservation programs – are now in place. Increasing investment in wind is driven by multiple factors. Stakeholders have interests both in public policy and meeting private investment objectives. Wind generator investors should consider project economics and potential impacts of energy decisions on human health. Specifically this article considers:changing environmental conditions in remote Alaska villages,impacts associated with climate change on human health,progress in better understanding wind energy potential through resource assessments and new tools for detailed feasibility and project planning,need for comprehensive monitoring and data analysis, andstate funding requirements and opportunity costs. Conclusion The energy policy choices ahead for Alaska will have important implications for Arctic population health, especially for those villages whose relatively small size and remote locations make energy a key component of subsistence lifestyles and community sustainability. Wind generation can contribute to meeting renewable energy goals and is a particularly important resource for rural and remote Alaskan communities currently dependent on diesel fuel for generating electricity and heat. PMID:23971014

76 FR 2365 - Notice of Effectiveness of Exempt Wholesale Generator Status

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-13

... Wholesale Generator Status January 6, 2011. Docket No. Ashtabula Wind III, LLC EG11-1-000 Iberdrola Renewables, Inc EG11-2-000 Flat Water Wind Farm, LLC EG11-3-000 Wildorado Wind Two, LLC EG11-4-000 Sandy Ridge Wind, LLC EG11-5-000 AES ES Deepwater, LLC EG11-6-000 Elk City II Wind, LLC EG11-7-000 Take notice...

Utility interconnection issues for wind power generation

NASA Technical Reports Server (NTRS)

Herrera, J. I.; Lawler, J. S.; Reddoch, T. W.; Sullivan, R. L.

1986-01-01

This document organizes the total range of utility related issues, reviews wind turbine control and dynamic characteristics, identifies the interaction of wind turbines to electric utility systems, and identifies areas for future research. The material is organized at three levels: the wind turbine, its controls and characteristics; connection strategies as dispersed or WPSs; and the composite issue of planning and operating the electric power system with wind generated electricity.

Status of Sundstrand research

NASA Technical Reports Server (NTRS)

Bateman, Don

1991-01-01

Wind shear detection status is presented in the form of view-graphs. The following subject areas are covered: second generation detection (Q-bias, gamma bias, temperature biases, maneuvering flight modulation, and altitude modulation); third generation wind shear detection (use wind shear computation to augment flight path and terrain alerts, modulation of alert thresholds based on wind/terrain data base, incorporate wind shear/terrain alert enhancements from predictive sensor data); and future research and development.

Matrix Converter Interface for a Wind Energy Conversion System: Issues and Limitations

NASA Astrophysics Data System (ADS)

Patki, Chetan; Agarwal, Vivek

2009-08-01

Variable speed grid connected wind energy systems sometimes involve AC-AC power electronic interface between the generator and the grid. Matrix converter is an attractive option for such applications. Variable speed of the wind generator demands variable voltage variable frequency at the generator terminal. Matrix converter is used in this work to generate such a supply. Also, matrix converter can be appropriately controlled to compensate the grid for non-linear, reactive loads. However, any change of power factor on the grid side reflects on the voltage magnitude on the wind generator side. It is highlighted that this may contradict the maximum power point tracking control requirements. All the results of this work are presented.

Wind turbine wake visualization and characteristics analysis by Doppler lidar.

PubMed

Wu, Songhua; Liu, Bingyi; Liu, Jintao; Zhai, Xiaochun; Feng, Changzhong; Wang, Guining; Zhang, Hongwei; Yin, Jiaping; Wang, Xitao; Li, Rongzhong; Gallacher, Daniel

2016-05-16

Wind power generation is growing fast as one of the most promising renewable energy sources that can serve as an alternative to fossil fuel-generated electricity. When the wind turbine generator (WTG) extracts power from the wind, the wake evolves and leads to a considerable reduction in the efficiency of the actual power generation. Furthermore, the wake effect can lead to the increase of turbulence induced fatigue loads that reduce the life time of WTGs. In this work, a pulsed coherent Doppler lidar (PCDL) has been developed and deployed to visualize wind turbine wakes and to characterize the geometry and dynamics of wakes. As compared with the commercial off-the-shelf coherent lidars, the PCDL in this work has higher updating rate of 4 Hz and variable physical spatial resolution from 15 to 60 m, which improves its capability to observation the instantaneous turbulent wind field. The wind speed estimation method from the arc scan technique was evaluated in comparison with wind mast measurements. Field experiments were performed to study the turbulent wind field in the vicinity of operating WTGs in the onshore and offshore wind parks from 2013 to 2015. Techniques based on a single and a dual Doppler lidar were employed for elucidating main features of turbine wakes, including wind velocity deficit, wake dimension, velocity profile, 2D wind vector with resolution of 10 m, turbulence dissipation rate and turbulence intensity under different conditions of surface roughness. The paper shows that the PCDL is a practical tool for wind energy research and will provide a significant basis for wind farm site selection, design and optimization.

Wind farms production: Control and prediction

NASA Astrophysics Data System (ADS)

El-Fouly, Tarek Hussein Mostafa

Wind energy resources, unlike dispatchable central station generation, produce power dependable on external irregular source and that is the incident wind speed which does not always blow when electricity is needed. This results in the variability, unpredictability, and uncertainty of wind resources. Therefore, the integration of wind facilities to utility electrical grid presents a major challenge to power system operator. Such integration has significant impact on the optimum power flow, transmission congestion, power quality issues, system stability, load dispatch, and economic analysis. Due to the irregular nature of wind power production, accurate prediction represents the major challenge to power system operators. Therefore, in this thesis two novel models are proposed for wind speed and wind power prediction. One proposed model is dedicated to short-term prediction (one-hour ahead) and the other involves medium term prediction (one-day ahead). The accuracy of the proposed models is revealed by comparing their results with the corresponding values of a reference prediction model referred to as the persistent model. Utility grid operation is not only impacted by the uncertainty of the future production of wind farms, but also by the variability of their current production and how the active and reactive power exchange with the grid is controlled. To address this particular task, a control technique for wind turbines, driven by doubly-fed induction generators (DFIGs), is developed to regulate the terminal voltage by equally sharing the generated/absorbed reactive power between the rotor-side and the gridside converters. To highlight the impact of the new developed technique in reducing the power loss in the generator set, an economic analysis is carried out. Moreover, a new aggregated model for wind farms is proposed that accounts for the irregularity of the incident wind distribution throughout the farm layout. Specifically, this model includes the wake effect and the time delay of the incident wind speed of the different turbines on the farm, and to simulate the fluctuation in the generated power more accurately and more closer to real-time operation. Recently, wind farms with considerable output power ratings have been installed. Their integrating into the utility grid will substantially affect the electricity markets. This thesis investigates the possible impact of wind power variability, wind farm control strategy, wind energy penetration level, wind farm location, and wind power prediction accuracy on the total generation costs and close to real time electricity market prices. These issues are addressed by developing a single auction market model for determining the real-time electricity market prices.

Percy Thomas wind generator designs

NASA Technical Reports Server (NTRS)

Lines, C. W.

1973-01-01

The technical and economic feasibilities of constructing a windpowered generator with a capacity of 2,000 to 4,000 kilowatt are considered. Possible benefits of an integrated wind generating electric energy source in an electric utility network are elaborated. Applications of a windpowered waterpump, including its use as a pumping source for hydroelectric pump storage operations, are also mentioned. It is concluded that the greatest potential of the wind generator is to generate heat directly and not conversion to electricity and then to heat.

Analysis and discussion on anti-thunder scheme of wind power generation system

NASA Astrophysics Data System (ADS)

Sun, Shuguang

2017-01-01

Anti-thunder scheme of wind power generation system is discussed in this paper. Through the research and analysis on the harm of the thunder, division of lightning protection zone and lightning protection measures are put forward, which has a certain practical significance on the design and application of wind power generation system.

Power Control of New Wind Power Generation System with Induction Generator Excited by Voltage Source Converter

NASA Astrophysics Data System (ADS)

Morizane, Toshimitsu; Kimura, Noriyuki; Taniguchi, Katsunori

This paper investigates advantages of new combination of the induction generator for wind power and the power electronic equipment. Induction generator is popularly used for the wind power generation. The disadvantage of it is impossible to generate power at the lower rotor speed than the synchronous speed. To compensate this disadvantage, expensive synchronous generator with the permanent magnets is sometimes used. In proposed scheme, the diode rectifier is used to convert the real power from the induction generator to the intermediate dc voltage, while only the reactive power necessary to excite the induction generator is supplied from the voltage source converter (VSC). This means that the rating of the expensive VSC is minimized and total cost of the wind power generation system is decreased compared to the system with synchronous generator. Simulation study to investigate the control strategy of proposed system is performed. The results show the reduction of the VSC rating is prospective.

Increasing power generation in horizontal axis wind turbines using optimized flow control

NASA Astrophysics Data System (ADS)

Cooney, John A., Jr.

In order to effectively realize future goals for wind energy, the efficiency of wind turbines must increase beyond existing technology. One direct method for achieving increased efficiency is by improving the individual power generation characteristics of horizontal axis wind turbines. The potential for additional improvement by traditional approaches is diminishing rapidly however. As a result, a research program was undertaken to assess the potential of using distributed flow control to increase power generation. The overall objective was the development of validated aerodynamic simulations and flow control approaches to improve wind turbine power generation characteristics. BEM analysis was conducted for a general set of wind turbine models encompassing last, current, and next generation designs. This analysis indicated that rotor lift control applied in Region II of the turbine power curve would produce a notable increase in annual power generated. This was achieved by optimizing induction factors along the rotor blade for maximum power generation. In order to demonstrate this approach and other advanced concepts, the University of Notre Dame established the Laboratory for Enhanced Wind Energy Design (eWiND). This initiative includes a fully instrumented meteorological tower and two pitch-controlled wind turbines. The wind turbines are representative in their design and operation to larger multi-megawatt turbines, but of a scale that allows rotors to be easily instrumented and replaced to explore new design concepts. Baseline data detailing typical site conditions and turbine operation is presented. To realize optimized performance, lift control systems were designed and evaluated in CFD simulations coupled with shape optimization tools. These were integrated into a systematic design methodology involving BEM simulations, CFD simulations and shape optimization, and selected experimental validation. To refine and illustrate the proposed design methodology, a complete design cycle was performed for the turbine model incorporated in the wind energy lab. Enhanced power generation was obtained through passive trailing edge shaping aimed at reaching lift and lift-to-drag goals predicted to optimize performance. These targets were determined by BEM analysis to improve power generation characteristics and annual energy production (AEP) for the wind turbine. A preliminary design was validated in wind tunnel experiments on a 2D rotor section in preparation for testing in the full atmospheric environment of the eWiND Laboratory. These tests were performed for the full-scale geometry and atmospheric conditions. Upon making additional improvements to the shape optimization tools, a series of trailing edge additions were designed to optimize power generation. The trailing edge additions were predicted to increase the AEP by up to 4.2% at the White Field site. The pieces were rapid-prototyped and installed on the wind turbine in March, 2014. Field tests are ongoing.

78 FR 760 - Potential Commercial Leasing for Wind Power on the Outer Continental Shelf (OCS) Offshore New...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-04

... Offshore Wind Collaborative,'' a public-private entity consisting of NYPA, the Long Island Power Authority... Island-New York City Offshore Wind Project'', is designed to generate at least 350 megawatts (MW) of electricity from offshore wind resources, with the ability to expand generation capacity to as much as 700 MW...

76 FR 61735 - Incidental Take Permit; Auwahi Wind Energy Generation Facility, Maui, HI; Draft Habitat...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-05

.... The proposed facility will consist of eight wind turbine generators (WTGs), a maintenance building, an... indicates that the Hawaiian hoary bat flies in the area proposed for wind turbine development, and that the... Hawaiian hoary bat are known to have collided with the existing wind turbine structures at the 30- megawatt...

Induction generators for Wind Energy Conversion Systems. Part I: review of induction generator with squirrel cage rotor. Part II: the Double Output Induction Generator (DOIG). Progress report, July-December 1975

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jayadev, T.S.

1976-02-01

The application of induction generators in Wind Energy Conversion Systems (WECS) is described. The conventional induction generator, which is an induction machine with a squirrel cage rotor, had been used in large wind power plants in Europe, but has not caught much attention until now by designers of large systems in this country. The induction generator with a squirrel cage rotor is described and useful design techniques to build induction generators for wind energy application are outlined. The Double Output Induction Generator (DOIG) - so called because power is fed into the grid from the stator, as well as themore » rotor is described. It is a wound rotor induction machine with power electronics to convert rotor slip frequency power to that of line frequency.« less

Effect of pole number and slot number on performance of dual rotor permanent magnet wind power generator using ferrite magnets

NASA Astrophysics Data System (ADS)

Xu, Peifeng; Shi, Kai; Sun, Yuxin; Zhua, Huangqiu

2017-05-01

Dual rotor permanent magnet (DRPM) wind power generator using ferrite magnets has the advantages of low cost, high efficiency, and high torque density. How to further improve the performance and reduce the cost of the machine by proper choice of pole number and slot number is an important problem to be solved when performing preliminarily design a DRPM wind generator. This paper presents a comprehensive performance comparison of a DRPM wind generator using ferrite magnets with different slot and pole number combinations. The main winding factors are calculated by means of the star of slots. Under the same machine volume and ferrite consumption, the flux linkage, back-electromotive force (EMF), cogging torque, output torque, torque pulsation, and losses are investigated and compared using finite element analysis (FEA). The results show that the slot and pole number combinations have an important impact on the generator properties.

Optimized Generator Designs for the DTU 10-MW Offshore Wind Turbine using GeneratorSE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sethuraman, Latha; Maness, Michael; Dykes, Katherine

Compared to land-based applications, offshore wind imposes challenges for the development of next generation wind turbine generator technology. Direct-drive generators are believed to offer high availability, efficiency, and reduced operation and maintenance requirements; however, previous research suggests difficulties in scaling to several megawatts or more in size. The resulting designs are excessively large and/or massive, which are major impediments to transportation logistics, especially for offshore applications. At the same time, geared wind turbines continue to sustain offshore market growth through relatively cheaper and lightweight generators. However, reliability issues associated with mechanical components in a geared system create significant operation andmore » maintenance costs, and these costs make up a large portion of overall system costs offshore. Thus, direct-drive turbines are likely to outnumber their gear-driven counterparts for this market, and there is a need to review the costs or opportunities of building machines with different types of generators and examining their competitiveness at the sizes necessary for the next generation of offshore wind turbines. In this paper, we use GeneratorSE, the National Renewable Energy Laboratory's newly developed systems engineering generator sizing tool to estimate mass, efficiency, and the costs of different generator technologies satisfying the electromagnetic, structural, and basic thermal design requirements for application in a very large-scale offshore wind turbine such as the Technical University of Denmark's (DTU) 10-MW reference wind turbine. For the DTU reference wind turbine, we use the previously mentioned criteria to optimize a direct-drive, radial flux, permanent-magnet synchronous generator; a direct-drive electrically excited synchronous generator; a medium-speed permanent-magnet generator; and a high-speed, doubly-fed induction generator. Preliminary analysis of leveled costs of energy indicate that for large turbines, the cost of permanent magnets and reliability issues associated with brushes in electrically excited machines are the biggest deterrents for building direct-drive systems. The advantage of medium-speed permanent-magnet machines over doubly-fed induction generators is evident, yet, variability in magnet prices and solutions to address reliability issues associated with gearing and brushes can change this outlook. This suggests the need to potentially pursue fundamentally new innovations in generator designs that help avoid high capital costs but still have significant reliability related to performance.« less

Optimized Generator Designs for the DTU 10-MW Offshore Wind Turbine using GeneratorSE: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sethuraman, Latha; Maness, Michael; Dykes, Katherine

Compared to land-based applications, offshore wind imposes challenges for the development of next generation wind turbine generator technology. Direct-drive generators are believed to offer high availability, efficiency, and reduced operation and maintenance requirements; however, previous research suggests difficulties in scaling to several megawatts or more in size. The resulting designs are excessively large and/or massive, which are major impediments to transportation logistics, especially for offshore applications. At the same time, geared wind turbines continue to sustain offshore market growth through relatively cheaper and lightweight generators. However, reliability issues associated with mechanical components in a geared system create significant operation andmore » maintenance costs, and these costs make up a large portion of overall system costs offshore. Thus, direct-drive turbines are likely to outnumber their gear-driven counterparts for this market, and there is a need to review the costs or opportunities of building machines with different types of generators and examining their competitiveness at the sizes necessary for the next generation of offshore wind turbines. In this paper, we use GeneratorSE, the National Renewable Energy Laboratory's newly developed systems engineering generator sizing tool to estimate mass, efficiency, and the costs of different generator technologies satisfying the electromagnetic, structural, and basic thermal design requirements for application in a very large-scale offshore wind turbine such as the Technical University of Denmark's (DTU) 10-MW reference wind turbine. For the DTU reference wind turbine, we use the previously mentioned criteria to optimize a direct-drive, radial flux, permanent-magnet synchronous generator; a direct-drive electrically excited synchronous generator; a medium-speed permanent-magnet generator; and a high-speed, doubly-fed induction generator. Preliminary analysis of leveled costs of energy indicate that for large turbines, the cost of permanent magnets and reliability issues associated with brushes in electrically excited machines are the biggest deterrents for building direct-drive systems. The advantage of medium-speed permanent-magnet machines over doubly-fed induction generators is evident, yet, variability in magnet prices and solutions to address reliability issues associated with gearing and brushes can change this outlook. This suggests the need to potentially pursue fundamentally new innovations in generator designs that help avoid high capital costs but still have significant reliability related to performance.« less

? stability of wind turbine switching control

NASA Astrophysics Data System (ADS)

Palejiya, Dushyant; Shaltout, Mohamed; Yan, Zeyu; Chen, Dongmei

2015-01-01

In order to maximise the wind energy capture, wind turbines are operated at variable speeds. Depending on the wind speed, a turbine switches between two operating modes: a low wind speed mode and a high wind speed mode. During the low wind speed mode, the control objective is to maximise wind energy capture by controlling both the blade pitch angle and the electrical generator torque. During the high wind speed mode, the control goal is to maintain the rated power generation by only adjusting the blade pitch angle. This paper establishes the stability criteria for the switching operation of wind turbines using ? gain under the nonlinear control framework. Also, the performance of the wind turbine system is analysed by using the step response, a well-known measure for second-order linear systems.

NWTC Aerodynamics Studies Improve Energy Capture and Lower Costs of Wind-Generated Electricity

DOE Office of Scientific and Technical Information (OSTI.GOV)

2015-08-01

Researchers at the National Wind Technology Center (NWTC) at the National Renewable Energy Laboratory (NREL) have expanded wind turbine aerodynamic research from blade and rotor aerodynamics to wind plant and atmospheric inflow effects. The energy capture from wind plants is dependent on all of these aerodynamic interactions. Research at the NWTC is crucial to understanding how wind turbines function in large, multiple-row wind plants. These conditions impact the cumulative fatigue damage of turbine structural components that ultimately effect the useful lifetime of wind turbines. This work also is essential for understanding and maximizing turbine and wind plant energy production. Bothmore » turbine lifetime and wind plant energy production are key determinants of the cost of wind-generated electricity.« less

Potential of neuro-fuzzy methodology to estimate noise level of wind turbines

NASA Astrophysics Data System (ADS)

Nikolić, Vlastimir; Petković, Dalibor; Por, Lip Yee; Shamshirband, Shahaboddin; Zamani, Mazdak; Ćojbašić, Žarko; Motamedi, Shervin

2016-01-01

Wind turbines noise effect became large problem because of increasing of wind farms numbers since renewable energy becomes the most influential energy sources. However, wind turbine noise generation and propagation is not understandable in all aspects. Mechanical noise of wind turbines can be ignored since aerodynamic noise of wind turbine blades is the main source of the noise generation. Numerical simulations of the noise effects of the wind turbine can be very challenging task. Therefore in this article soft computing method is used to evaluate noise level of wind turbines. The main goal of the study is to estimate wind turbine noise in regard of wind speed at different heights and for different sound frequency. Adaptive neuro-fuzzy inference system (ANFIS) is used to estimate the wind turbine noise levels.

Improving Energy Security for Air Force Installations

DTIC Science & Technology

2015-09-01

Wind power is a mature technology, with wind turbines first being used for electricity in the late 19th century. The Air Force operates two wind ...company, and the military unit receives energy credits back on its bill. Two concepts are important when considering the turbine size for a wind ...generation and consumption must remain balanced for a grid, so wind turbines are rarely used as a sole energy source since power is only generated

Impacts of Wind and Solar on Fossil-Fueled Generators: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lew, D.; Brinkman, G.; Kumar, N.

2012-08-01

High penetrations of wind and solar power will impact the operations of the remaining generators on the power system. Regional integration studies have shown that wind and solar may cause fossil-fueled generators to cycle on and off and ramp down to part load more frequently and potentially more rapidly. Increased cycling, deeper load following, and rapid ramping may result in wear-and-tear impacts on fossil-fueled generators that lead to increased capital and maintenance costs, increased equivalent forced outage rates, and degraded performance over time. Heat rates and emissions from fossil-fueled generators may be higher during cycling and ramping than during steady-statemore » operation. Many wind and solar integration studies have not taken these increased cost and emissions impacts into account because data have not been available. This analysis considers the cost and emissions impacts of cycling and ramping of fossil-fueled generation to refine assessments of wind and solar impacts on the power system.« less

Transient Stability and Frequency Response of the US Western Interconnection Under Conditions of High Wind and Solar Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Nicholas W.; Shao, Miaolei; Pajic, Slobodan

The addition of large amounts of wind and solar generation to bulk power systems that are traditionally subject to operating constraints set by transient stability and frequency response limitations is the subject of considerable concern in the industry. The US Western Interconnection (WI) is expected to experience substantial additional growth in both wind and solar generation. These plants will, to some extent, displace large central station thermal generation, both coal and gas-fired, which have traditionally helped maintain stability. This paper reports the results of a study that investigated the transient stability and frequency response of the WI with high penetrationsmore » of wind and solar generation. The main goals of this work were to (1) create a realistic, baseline model of the WI, (2) test selected transient stability and frequency events, (3) investigate the impact of large amounts of wind and solar generation, and (4) examine means to improve performance.« less

The Coast Artillery Journal. Volume 58, Number 2, February 1923

DTIC Science & Technology

1923-02-01

firing mechanism block with a fresh primer in place. No.5 acted as a powder runner between the powder pit and No.2. Nos. 6 and 7 carried the loading...obstruct these routes. Xumerous passive obstructions have been conceived: metallic cables raised and maintained in the air by kites ; cables shot into the

The Status of Infantry TOW, LAW, and Dragon Training in USAREUR.

DTIC Science & Technology

1977-11-01

TOW duties (guard, CQ runner , etc.); (b) Permanent assignment to other than TOW duties; (c) medical and dental appointments and drug and alcohol abuse...in training areas would be most helpful, and a third said American tanks and ve- hicles could be mocked-up to look like enemy targets and that kites

76 FR 36482 - Proposed Flood Elevation Determinations

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-22

... Marian. WPA Canal Tributary 1 Approximately 1,612 None + 71 City of St. Cloud, feet upstream of the... Kite Avenue. WPA Canal Tributary 1-1 At the WPA Canal None + 75 City of St. Cloud, Tributary 1..., FL 34741. City of St. Cloud Maps are available for inspection at City Hall, Public Works Department...

Examining Risk-Taking Behavior and Sensation Seeking Requirement in Extreme Athletes

ERIC Educational Resources Information Center

Agilonu, Ali; Bastug, Gulsum; Mutlu, Tonguc Osman; Pala, Adem

2017-01-01

Extreme sports are sport branches which include actions, adventures, risks and difficulties more rather than other sports. Special materials are used in sport branches such as surfing, kite surfing, sailing, snowboarding, paragliding, diving, mountaineering, motor sports and adrenaline release is more rather than in other sport branches. On the…

14 CFR 101.27 - ATC notification for all launches.

Code of Federal Regulations, 2013 CFR

2013-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.27 ATC notification for all launches. No person may operate an unmanned rocket other than a Class 1—Model Rocket unless that person gives the following information to the FAA...

14 CFR 101.27 - ATC notification for all launches.

Code of Federal Regulations, 2010 CFR

2010-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.27 ATC notification for all launches. No person may operate an unmanned rocket other than a Class 1—Model Rocket unless that person gives the following information to the FAA...

14 CFR 101.27 - ATC notification for all launches.

Code of Federal Regulations, 2014 CFR

2014-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.27 ATC notification for all launches. No person may operate an unmanned rocket other than a Class 1—Model Rocket unless that person gives the following information to the FAA...

14 CFR 101.27 - ATC notification for all launches.

Code of Federal Regulations, 2012 CFR

2012-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.27 ATC notification for all launches. No person may operate an unmanned rocket other than a Class 1—Model Rocket unless that person gives the following information to the FAA...

14 CFR 101.27 - ATC notification for all launches.

Code of Federal Regulations, 2011 CFR

2011-01-01

... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES MOORED BALLOONS, KITES, AMATEUR ROCKETS AND UNMANNED FREE BALLOONS Amateur Rockets § 101.27 ATC notification for all launches. No person may operate an unmanned rocket other than a Class 1—Model Rocket unless that person gives the following information to the FAA...

Afghanistan and Multiculturalism in Khaled Hosseini's Novels: Study of Place and Diversity

ERIC Educational Resources Information Center

Agnello, Mary F.; Todd, Reese H.; Olaniran, Bolanle; Lucey, Thomas A.

2009-01-01

Purpose: The purpose of this paper is to frame Khaled Hosseini's novels, "The Kite Runner" and "A Thousand Splendid Suns", as literature to expand and enhance the American secondary curriculum with multicultural themes based on Afghanistan as a geographical and cultural place in a dynamic, diverse, and complex world more…

In "Other" Words: Some Thoughts on the Transferability of Collocations

ERIC Educational Resources Information Center

Odlin, Terence

2011-01-01

In discussions of cross-linguistic influence (also known as language transfer), the focus is usually on the influence of a particular structure in a particular instance of language contact, for instance, the negative transfer of serial verbs by Vietnamese learners of English: "She has managed to rise the kite fly over the tallest…

Status of wind-energy conversion

NASA Technical Reports Server (NTRS)

Thomas, R. L.; Savino, J. M.

1973-01-01

The utilization of wind energy is technically feasible as evidenced by the many past demonstrations of wind generators. The cost of energy from the wind has been high compared to fossil fuel systems. A sustained development effort is needed to obtain economical systems. The variability of the wind makes it an unreliable source on a short-term basis. However, the effects of this variability can be reduced by storage systems or connecting wind generators to fossil fuel systems, hydroelectric systems, or dispersing them throughout a large grid network. The NSF and NASA-Lewis Research Center have sponsored programs for the utilization of wind energy.

Wind turbine generator interaction with conventional diesel generators on Block Island, Rhode Island. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Wilreker, V. F.; Stiller, P. H.; Scott, G. W.; Kruse, V. J.; Smith, R. F.

1984-01-01

Primary results are summarized for a three-part study involving the effects of connecting a MOD-OA wind turbine generator to an isolated diesel power system. The MOD-OA installation considered was the third of four experimental nominal 200 kW wind turbines connected to various utilities under the Federal Wind Energy Program and was characterized by the highest wind energy penetration levels of four sites. The study analyses address: fuel displacement, dynamic interaction, and three modes of reactive power control. These analyses all have as their basis the results of the data acquisition program conducted on Block Island, Rhode Island.

Mate desertion in the snail kite

USGS Publications Warehouse

Beissinger, S.R.; Snyder, N.F.R.

1988-01-01

Mate desertion during the breeding cycle was documented at 28 of 36 (78%) snail kite, Rostrhamus sociabilis nests in Florida between 1979 and 1983. Offspring mortality occurred at only one deserted nest, however. Parents that were deserted by their mates continued to care for their young until independence (3?5 additional weeks) and provided snails at a rate similar to that of both parents combined before desertion. Males and females deserted with nearly equal frequency, except in 1982 when more females deserted. No desertion occurred during drought years, whereas desertion occurred at nearly every nest during favourable conditions. The occurrence of mate desertion was generally related to indirect measures of snail abundance: foraging range, snail delivery rates to the young and growth rates. Small broods were deserted more frequently by females than by males and tended to be deserted earlier than large ones. After desertion, deserters had the opportunity to re-mate and nest again since breeding seasons were commonly lengthy, but whether they did so was impossible to determine conclusively in most cases. The deserted bird sometimes incurred increased energetic costs and lost breeding opportunities during periods of monoparental care.

Space-Spurred Metallized Materials

NASA Technical Reports Server (NTRS)

1990-01-01

Spurred R&D toward improved vacuum metallizing techniques led to an extensive line of commercial products, from insulated outdoor garments to packaging for foods, from wall coverings to window shades, from life rafts to candy wrappings, reflective blankets to photographic reflectors. Metallized Products, Inc. (MPI) was one of the companies that worked with NASA in development of the original space materials. MPI markets its own metallized products and supplies materials to other manufacturers. One of the most widely used MPI products is TXG laminate. An example is a reflective kite, the S.O.S. Signal Kite that can be flown as high as 200 feet to enhance radar and visual detectability. It offers a boon to campers, hikers, mountain climbers and boaters. It is produced by Solar Reflections, Inc. The company also markets a solar reflective hat. Another example is by Pro-Tektion, Inc. to provide protection for expensive musical equipment that have sensitive electronic components subject to damage from the heat of stage lights, dust, or rain at outdoor concerts. MP supplied the material and acceptance of the covers by the sound industry has been excellent.

Reconstructing historical habitat data with predictive models Read More: http://www.esajournals.org/doi/abs/10.1890/13-0327.1

USGS Publications Warehouse

Zweig, Christa L.; Kitchens, Wiley M.

2014-01-01

Historical vegetation data are important to ecological studies, as many structuring processes operate at long time scales, from decades to centuries. Capturing the pattern of variability within a system (enough to declare a significant change from past to present) relies on correct assumptions about the temporal scale of the processes involved. Sufficient long-term data are often lacking, and current techniques have their weaknesses. To address this concern, we constructed multistate and artificial neural network models (ANN) to provide fore- and hindcast vegetation communities considered critical foraging habitat for an endangered bird, the Florida Snail Kite (Rostrhamus sociabilis). Multistate models were not able to hindcast due to our data not satisfying a detailed balance requirement for time reversibility in Markovian dynamics. Multistate models were useful for forecasting and providing environmental variables for the ANN. Results from our ANN hindcast closely mirrored the population collapse of the Snail Kite population using only environmental data to inform the model. The parallel between the two gives us confidence in the hindcasting results and their use in future demographic models.

Wet and wild: results from a pilot study assessing injuries among recreational water users in Western Australia.

PubMed

Pikora, T J; Braham, R; Hill, C; Mills, C

2011-06-01

To identify, describe and compare injuries among three water sport activities: kite surfing (KS), personal watercraft (PWC) and towed water sports (TWS). The study was a cross sectional, online survey. The setting was on Perth, Western Australia's popular beaches and riverbanks. Main outcome measures were number of injuries and level of severity; level of exposure and protection measures. Overall, 43% reported at least one injury in the past 12 months, a rate of 22.3 injuries per 100 h. Kite surfers were more likely to report an injury than PWC or TWS. One-half of injuries occurred while on the water. Most injuries were caused by landing awkwardly (56%) and/or trying new tricks (41%). Despite 90% of respondents having used at least one personal protective equipment (PPE) item, half (49%) reported always using a personal floatation device. This study provided information on KS, PWC and TWS injuries as well as a range of safety behaviours. It is recommended that these results form the basis of further research to reduce injury rates and encourage the use of PPE items.

Efficiency of the DOMUS 750 vertical-axis wind turbine

NASA Astrophysics Data System (ADS)

Hallock, Kyle; Rasch, Tyler; Ju, Guoqiang; Alonso-Marroquin, Fernando

2017-06-01

The aim of this paper is to present some preliminary results on the efficiency of a wind turbine for an off-grid housing unit. To generate power, the unit uses a photovoltaic solar array and a vertical-axis wind turbine (VAWT). The existing VAWT was analysed to improve efficiency and increase power generation. There were found to be two main sources of inefficiency: 1. the 750W DC epicyclic generator performed poorly in low winds, and 2. the turbine blades wobbled, allowing for energy loss due to off-axis rotation. A 12V DC permanent magnet alternator was chosen that met the power requirements of the housing unit and would generate power at lower wind speeds. A support bracket was designed to prevent the turbine blades from wobbling.

1 MVA HTS-2G Generator for Wind Turbines

NASA Astrophysics Data System (ADS)

Kovalev, K. L.; Poltavets, V. N.; Ilyasov, R. I.; Verzhbitsky, L. G.; Kozub, S. S.

2017-10-01

The calculation, design simulations and design performance of 1 MVA HTS-2G (second-generation high-temperature superconductor) Generator for Wind Turbines were done in 2013-2014 [1]. The results of manufacturing and testing of 1 MVA generator are presented in the article. HTS-2G field coils for the rotor were redesigned, fabricated and tested. The tests have shown critical current of the coils, 41-45 A (self field within the ferromagnetic core, T = 77 K), which corresponds to the current of short samples at self field. Application of the copper inner frame on the pole has improved internal cooling conditions of HTS coil windings and reduced the magnetic field in the area, thereby increased the critical current value. The original construction of the rotor with a rotating cryostat was developed, which decreases the thermal in-flow to the rotor. The stator of 1 MW HTS-2G generator has been manufactured. In order to improve the specific weight of the generator, the wave (harmonic drive) multiplier was used, which provides increasing RPM from 15 RPM up to 600 RPM. The total mass of the multiplier and generator is significantly smaller compared to traditional direct-drive wind turbines generators [2-7]. Parameters of the multiplier and generator were chosen based on the actual parameters of wind turbines, namely: 15 RPM, power is 1 MVA. The final test of the assembled synchronous generator with HTS-2G field coils for Wind Turbines with output power 1 MVA was completed during 2015.

78 FR 77343 - Small Business Size Standards: Utilities

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-23

... (such as solar, wind, biomass, geothermal) as well as other industries, where power generation is...: namely NAICS 221114 (Solar Electric Power Generation), NAICS 221115 (Wind Electric Power Generation... Electric Power 4 million 250 employees. Generation. megawatt hours. [[Page 77348

Mod-5A wind turbine generator program design report. Volume 3: Final design and system description, book 1

NASA Technical Reports Server (NTRS)

1984-01-01

The design, development and analysis of the 7.3 MW MOD-5A wind turbine generator is documented. Volume 3, book 1 describes the performance and characteristics of the MOD-5A wind turbine generator in its final configuration. Each subsystem - the rotor, drivetrain, nacelle, tower and foundation is described in detail.

Design, economic and system considerations of large wind-driven generators

NASA Technical Reports Server (NTRS)

Jorgensen, G. E.; Lotker, M.; Meier, R. C.; Brierley, D.

1976-01-01

The increased search for alternative energy sources has lead to renewed interest and studies of large wind-driven generators. This paper presents the results and considerations of such an investigation. The paper emphasizes the concept selection of wind-driven generators, system optimization, control system design, safety aspects, economic viability on electric utility systems and potential electric system interfacing problems.

Western Wind and Solar Integration Study Phase 3A: Low Levels of Synchronous Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Nicholas W.; Leonardi, Bruno; D'Aquila, Robert

The stability of the North American electric power grids under conditions of high penetrations of wind and solar is a significant concern and possible impediment to reaching renewable energy goals. The 33% wind and solar annual energy penetration considered in this study results in substantial changes to the characteristics of the bulk power system. This includes different power flow patterns, different commitment and dispatch of existing synchronous generation, and different dynamic behavior from wind and solar generation. The Western Wind and Solar Integration Study (WWSIS), sponsored by the U.S. Department of Energy, is one of the largest regional solar andmore » wind integration studies to date. In multiple phases, it has explored different aspects of the question: Can we integrate large amounts of wind and solar energy into the electric power system of the West? The work reported here focused on the impact of low levels of synchronous generation on the transient stability performance in one part of the region in which wind generation has displaced synchronous thermal generation under highly stressed, weak system conditions. It is essentially an extension of WWSIS-3. Transient stability, the ability of the power system to maintain synchronism among all elements following disturbances, is a major constraint on operations in many grids, including the western U.S. and Texas systems. These constraints primarily concern the performance of the large-scale bulk power system. But grid-wide stability concerns with high penetrations of wind and solar are still not thoroughly understood. This work focuses on 'traditional' fundamental frequency stability issues, such as maintaining synchronism, frequency, and voltage. The objectives of this study are to better understand the implications of low levels of synchronous generation and a weak grid on overall system performance by: 1) Investigating the Western Interconnection under conditions of both high renewable generation (e.g., wind and solar) and low synchronous generation (e.g., significant coal power plant decommitment or retirement); and 2) Analyzing both the large-scale stability of the Western Interconnection and regional stability issues driven by more geographically dispersed renewable generation interacting with a transmission grid that evolved with large, central station plants at key nodes. As noted above, the work reported here is an extension of the research performed in WWSIS-3.« less

Costs of solar and wind power variability for reducing CO2 emissions.

PubMed

Lueken, Colleen; Cohen, Gilbert E; Apt, Jay

2012-09-04

We compare the power output from a year of electricity generation data from one solar thermal plant, two solar photovoltaic (PV) arrays, and twenty Electric Reliability Council of Texas (ERCOT) wind farms. The analysis shows that solar PV electricity generation is approximately one hundred times more variable at frequencies on the order of 10(-3) Hz than solar thermal electricity generation, and the variability of wind generation lies between that of solar PV and solar thermal. We calculate the cost of variability of the different solar power sources and wind by using the costs of ancillary services and the energy required to compensate for its variability and intermittency, and the cost of variability per unit of displaced CO(2) emissions. We show the costs of variability are highly dependent on both technology type and capacity factor. California emissions data were used to calculate the cost of variability per unit of displaced CO(2) emissions. Variability cost is greatest for solar PV generation at $8-11 per MWh. The cost of variability for solar thermal generation is $5 per MWh, while that of wind generation in ERCOT was found to be on average $4 per MWh. Variability adds ~$15/tonne CO(2) to the cost of abatement for solar thermal power, $25 for wind, and $33-$40 for PV.

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

NASA Astrophysics Data System (ADS)

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

2016-07-01

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

Control Strategies for Smoothing of Output Power of Wind Energy Conversion Systems

NASA Astrophysics Data System (ADS)

Pratap, Alok; Urasaki, Naomitsu; Senju, Tomonobu

2013-10-01

This article presents a control method for output power smoothing of a wind energy conversion system (WECS) with a permanent magnet synchronous generator (PMSG) using the inertia of wind turbine and the pitch control. The WECS used in this article adopts an AC-DC-AC converter system. The generator-side converter controls the torque of the PMSG, while the grid-side inverter controls the DC-link and grid voltages. For the generator-side converter, the torque command is determined by using the fuzzy logic. The inputs of the fuzzy logic are the operating point of the rotational speed of the PMSG and the difference between the wind turbine torque and the generator torque. By means of the proposed method, the generator torque is smoothed, and the kinetic energy stored by the inertia of the wind turbine can be utilized to smooth the output power fluctuations of the PMSG. In addition, the wind turbines shaft stress is mitigated compared to a conventional maximum power point tracking control. Effectiveness of the proposed method is verified by the numerical simulations.

Optimizing Wind And Hydropower Generation Within Realistic Reservoir Operating Policy

NASA Astrophysics Data System (ADS)

Magee, T. M.; Clement, M. A.; Zagona, E. A.

2012-12-01

Previous studies have evaluated the benefits of utilizing the flexibility of hydropower systems to balance the variability and uncertainty of wind generation. However, previous hydropower and wind coordination studies have simplified non-power constraints on reservoir systems. For example, some studies have only included hydropower constraints on minimum and maximum storage volumes and minimum and maximum plant discharges. The methodology presented here utilizes the pre-emptive linear goal programming optimization solver in RiverWare to model hydropower operations with a set of prioritized policy constraints and objectives based on realistic policies that govern the operation of actual hydropower systems, including licensing constraints, environmental constraints, water management and power objectives. This approach accounts for the fact that not all policy constraints are of equal importance. For example target environmental flow levels may not be satisfied if it would require violating license minimum or maximum storages (pool elevations), but environmental flow constraints will be satisfied before optimizing power generation. Additionally, this work not only models the economic value of energy from the combined hydropower and wind system, it also captures the economic value of ancillary services provided by the hydropower resources. It is recognized that the increased variability and uncertainty inherent with increased wind penetration levels requires an increase in ancillary services. In regions with liberalized markets for ancillary services, a significant portion of hydropower revenue can result from providing ancillary services. Thus, ancillary services should be accounted for when determining the total value of a hydropower system integrated with wind generation. This research shows that the end value of integrated hydropower and wind generation is dependent on a number of factors that can vary by location. Wind factors include wind penetration level, variability due to geographic distribution of wind resources, and forecast error. Electric power system factors include the mix of thermal generation resources, available transmission, demand patterns, and market structures. Hydropower factors include relative storage capacity, reservoir operating policies and hydrologic conditions. In addition, the wind, power system, and hydropower factors are often interrelated because stochastic weather patterns can simultaneously influence wind generation, power demand, and hydrologic inflows. One of the central findings is that the sensitivity of the model to changes cannot be performed one factor at a time because the impact of the factors is highly interdependent. For example, the net value of wind generation may be very sensitive to changes in transmission capacity under some hydrologic conditions, but not at all under others.

Effects of wind energy generation and white-nose syndrome on the viability of the Indiana bat

USGS Publications Warehouse

Erickson, Richard A.; Thogmartin, Wayne E.; Diffendorfer, James E.; Russell, Robin E.; Szymanski, Jennifer A.

2016-01-01

Wind energy generation holds the potential to adversely affect wildlife populations. Species-wide effects are difficult to study and few, if any, studies examine effects of wind energy generation on any species across its entire range. One species that may be affected by wind energy generation is the endangered Indiana bat (Myotis sodalis), which is found in the eastern and midwestern United States. In addition to mortality from wind energy generation, the species also faces range-wide threats from the emerging infectious fungal disease, white-nose syndrome (WNS). White-nose syndrome, caused by Pseudogymnoascus destructans, disturbs hibernating bats leading to high levels of mortality. We used a spatially explicit full-annual-cycle model to investigate how wind turbine mortality and WNS may singly and then together affect population dynamics of this species. In the simulation, wind turbine mortality impacted the metapopulation dynamics of the species by causing extirpation of some of the smaller winter colonies. In general, effects of wind turbines were localized and focused on specific spatial subpopulations. Conversely, WNS had a depressive effect on the species across its range. Wind turbine mortality interacted with WNS and together these stressors had a larger impact than would be expected from either alone, principally because these stressors together act to reduce species abundance across the spectrum of population sizes. Our findings illustrate the importance of not only prioritizing the protection of large winter colonies as is currently done, but also of protecting metapopulation dynamics and migratory connectivity.

Effects of wind energy generation and white-nose syndrome on the viability of the Indiana bat.

PubMed

Erickson, Richard A; Thogmartin, Wayne E; Diffendorfer, Jay E; Russell, Robin E; Szymanski, Jennifer A

2016-01-01

Wind energy generation holds the potential to adversely affect wildlife populations. Species-wide effects are difficult to study and few, if any, studies examine effects of wind energy generation on any species across its entire range. One species that may be affected by wind energy generation is the endangered Indiana bat ( Myotis sodalis ), which is found in the eastern and midwestern United States. In addition to mortality from wind energy generation, the species also faces range-wide threats from the emerging infectious fungal disease, white-nose syndrome (WNS). White-nose syndrome, caused by Pseudogymnoascus destructans , disturbs hibernating bats leading to high levels of mortality. We used a spatially explicit full-annual-cycle model to investigate how wind turbine mortality and WNS may singly and then together affect population dynamics of this species. In the simulation, wind turbine mortality impacted the metapopulation dynamics of the species by causing extirpation of some of the smaller winter colonies. In general, effects of wind turbines were localized and focused on specific spatial subpopulations. Conversely, WNS had a depressive effect on the species across its range. Wind turbine mortality interacted with WNS and together these stressors had a larger impact than would be expected from either alone, principally because these stressors together act to reduce species abundance across the spectrum of population sizes. Our findings illustrate the importance of not only prioritizing the protection of large winter colonies as is currently done, but also of protecting metapopulation dynamics and migratory connectivity.

Investigating the effect of increased wind generation capacity on investment in transmission infrastructure

NASA Astrophysics Data System (ADS)

Braswell, Michael G.

The transmission network that connects electricity generators with consumers is a critical yet often-overlooked component of the nation's electrical power infrastructure. However, the transmission grid has suffered from chronic underinvestment in recent decades due to various economic and regulatory factors that impede timely and efficient investments in transmission. One factor that might help offset these obstacles to transmission is the growth in wind power generation. The assumption among many in the electrical power industry is that wind power investments necessarily require greater investment in transmission due to the fact that wind power is a geographically-restricted resource and cannot always be situated close to areas of high electricity demand. However, to date there have been few, if any, empirical studies to verify this connection. This paper discusses a state-by-state empirical study exploring the relationship between increased wind generation capacity and the level of investment in transmission infrastructure. This study begins with the hypothesis that increases in installed wind generation capacity, in combination with other policies that promote wind energy more generally, should result in higher levels of transmission investment. Using data from the Federal Energy Regulatory Commission (FERC) and the American Wind Energy Association (AWEA), this paper develops regression models suggesting that wind investment has a small but distinct positive impact on transmission investment. This paper then explores the effects of other state renewable energy promotion policies, and discusses the policy implications of these findings.

Is There a Future for Nuclear Power? Wind and Emission Reduction Targets in Fossil-Fuel Alberta

PubMed Central

Duan, Jun; Lynch, Rachel

2016-01-01

This paper explores the viability of relying on wind power to replace upwards of 60% of electricity generation in Alberta that would be lost if coal-fired generation is phased out. Using hourly wind data from 17 locations across Alberta, we are able to simulate the potential wind power output available to the Alberta grid when modern, 3.5 MW-capacity wind turbines are spread across the province. Using wind regimes for the years 2006 through 2015, we find that available wind power is less than 60% of installed capacity 98% of the time, and below 30% of capacity 74% of the time. There is only a small amount of correlation between wind speeds at different locations, but yet it remains necessary to rely on fossil fuel generation. Then, based on the results from a grid allocation model, we find that CO2 emissions can be reduced by about 30%, but only through a combination of investment in wind energy and reliance on purchases of hydropower from British Columbia. Only if nuclear energy is permitted into the generation mix would Alberta be able to meet its CO2-emissions reduction target in the electricity sector. With nuclear power, emissions can be reduced by upwards of 85%. PMID:27902712

Is There a Future for Nuclear Power? Wind and Emission Reduction Targets in Fossil-Fuel Alberta.

PubMed

van Kooten, G Cornelis; Duan, Jun; Lynch, Rachel

2016-01-01

This paper explores the viability of relying on wind power to replace upwards of 60% of electricity generation in Alberta that would be lost if coal-fired generation is phased out. Using hourly wind data from 17 locations across Alberta, we are able to simulate the potential wind power output available to the Alberta grid when modern, 3.5 MW-capacity wind turbines are spread across the province. Using wind regimes for the years 2006 through 2015, we find that available wind power is less than 60% of installed capacity 98% of the time, and below 30% of capacity 74% of the time. There is only a small amount of correlation between wind speeds at different locations, but yet it remains necessary to rely on fossil fuel generation. Then, based on the results from a grid allocation model, we find that CO2 emissions can be reduced by about 30%, but only through a combination of investment in wind energy and reliance on purchases of hydropower from British Columbia. Only if nuclear energy is permitted into the generation mix would Alberta be able to meet its CO2-emissions reduction target in the electricity sector. With nuclear power, emissions can be reduced by upwards of 85%.

77 FR 9225 - Notice of Effectiveness of Exempt Wholesale Generator Status

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-16

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Notice of Effectiveness of Exempt Wholesale Generator Status Docket Nos. Fire Island Wind, LLC EG12-9-000 Kaheawa Wind Power II, LLC EG12-12-000 Broken Bow Wind, LLC EG12-13-000 Crofton Bluffs Wind, LLC EG12-14-000 NRG Texas Power LLC EG12-15...

Systems Engineering Publications | Wind | NREL

Science.gov Websites

Different Turbine Heights. AIAA SciTech Forum: 35th Wind Energy Symposium, Grapevine, Texas, doi:10.2514 Tool for Variable-Speed Wind Turbine Generators. NREL/TP-5000-66462, doi:10.2514/6.2017-1619. Seturaman Turbine using GeneratorSE. AIAA SciTech Forum: 35th Wind Energy Symposium, Grapevine, Texas, doi:10.2172

Analysis of the electrical harmonic characteristics of a slip recovery variable speed generating system for wind turbine applications

NASA Astrophysics Data System (ADS)

Herrera, J. I.; Reddoch, T. W.

1988-02-01

Variable speed electric generating technology can enhance the general use of wind energy in electric utility applications. This enhancement results from two characteristic properties of variable speed wind turbine generators: an improvement in drive train damping characteristics, which results in reduced structural loading on the entire wind turbine system, and an improvement in the overall efficiency by using a more sophisticated electrical generator. Electronic converter systems are the focus of this investigation -- in particular, the properties of a wound-rotor induction generator with the slip recovery system and direct-current link converter. Experience with solid-state converter systems in large wind turbines is extremely limited. This report presents measurements of electrical performances of the slip recovery system and is limited to the terminal characteristics of the system. Variable speed generating systems working effectively in utility applications will require a satisfactory interface between the turbine/generator pair and the utility network. The electrical testing described herein focuses largely on the interface characteristics of the generating system. A MOD-O wind turbine was connected to a very strong system; thus, the voltage distortion was low and the total harmonic distortion in the utility voltage was less than 3 percent (within the 5 percent limit required by most utilities). The largest voltage component of a frequency below 60 Hz was 40 dB down from the 60-Hz less than component.

Development of large, horizontal-axis wind turbines

NASA Technical Reports Server (NTRS)

Baldwin, D. H.; Kennard, J.

1985-01-01

A program to develop large, horizontal-axis wind turbines is discussed. The program is directed toward developing the technology for safe, reliable, environmentally acceptable large wind turbines that can generate a significant amount of electricity at costs competitive with those of conventional electricity-generating systems. In addition, these large wind turbines must be fully compatible with electric utility operations and interface requirements. Several ongoing projects in large-wind-turbine development are directed toward meeting the technology requirements for utility applications. The machines based on first-generation technology (Mod-OA and Mod-1) successfully completed their planned periods of experimental operation in June, 1982. The second-generation machines (Mod-2) are in operation at selected utility sites. A third-generation machine (Mod-5) is under contract. Erection and initial operation of the Mod-5 in Hawaii should take place in 1986. Each successive generation of technology increased reliability and energy capture while reducing the cost of electricity. These advances are being made by gaining a better understanding of the system-design drivers, improving the analytical design tools, verifying design methods with operating field data, and incorporating new technology and innovative designs. Information is given on the results from the first- and second-generation machines (Mod-OA, - 1, and -2), the status of the Department of Interior, and the status of the third-generation wind turbine (Mod-5).

Characterization of fecal vancomycin-resistant enterococci with acquired and intrinsic resistance mechanisms in wild animals, Spain.

PubMed

Lozano, Carmen; Gonzalez-Barrio, David; Camacho, Maria Cruz; Lima-Barbero, Jose Francisco; de la Puente, Javier; Höfle, Ursula; Torres, Carmen

2016-11-01

The objectives were to evaluate the presence of vancomycin-resistant enterococci with acquired (VRE-a) and intrinsic (VRE-i) resistance mechanisms in fecal samples from different wild animals, and analyze their phenotypes and genotypes of antimicrobial resistance. A total of 348 cloacal/rectal samples from red-legged partridges (127), white storks (81), red kites (59), and wild boars (81) (June 2014/February 2015) were inoculated in Slanetz-Bartley agar supplemented with vancomycin (4 μg/mL). We investigated the susceptibility to 12 antimicrobials and the presence of 19 antimicrobial resistance and five virulence genes. In addition, we performed multilocus sequence typing, detection of IS16 and studied Tn1546 structure. One VRE-a isolate was identified in one wild boar. This isolate was identified as Enterococcus faecium, harbored vanA gene included into Tn1546 (truncated with IS1542/IS1216), and belonged to the new ST993. This isolate contained the erm(A), erm(B), tet(M), dfrG, and dfrK genes. Neither element IS16 nor the studied virulence genes were detected. Ninety-six VRE-i isolates were identified (89 Enterococcus gallinarum and seven Enterococcus casseliflavus), with the following prevalence: red kites (71.2 %), white storks (46.9 %), red-legged partridges (7.9 %), and wild boars (4.9 %). Most E. gallinarum isolates showed resistance to tetracycline (66.3 %) and/or erythromycin (46.1 %). High-level resistance to aminoglycosides was present among our VRE-i isolates: kanamycin (22.9 %), streptomycin (11.5 %), and gentamicin (9.4 %). In general, VRE-i isolates of red kites showed higher rates of resistance for non-glycopeptide agents than those of other animal species. The dissemination of acquired resistance mechanisms in natural environments could have implications in the global spread of resistance with public health implications.

A kite-based approach for water-vapor lidar calibration and application to multi-platform intercomparison in the Western Mediterranean during ChArMEx/ADRIMED

NASA Astrophysics Data System (ADS)

Totems, Julien; Chazette, Patrick; Dulac, François; Hassanzadeh, Sahar

2015-04-01

In the framework of the ADRIMED campaign included in the ChArMEx (Chemistry Aerosol Mediterranean Experiment) research program, performed in June 2013 in the western Mediterranean, the mobile Water vapor Aerosol LIdar (WALI) developed by LSCE was deployed at Cap d'en Font on the island of Menorca (Spain). Alongside an elastic backscatter channel, it features depolarization, N2- and H2O-Raman channels, the two latter yielding profiles of atmospheric water vapor mixing ratio (WVMR). The water content thus provided by the lidar is essential to validate models or satellite water vapor products for meteorological purposes. It also proved to be very helpful in characterizing particle types and sources, especially for the multi-layer situations observed during the ChArMEx/ADRIMED special observation period. Beforehand, however, a precise calibration of the WVMR had to be done on-site. Balloon rawindsoundings performed by CNES were available about 10 km off-site on Saint-Lluis aerodrome or 100 km away on Majorca for this purpose, but strong inhomogeneities in the WVMR observed under 2 km altitude prevent an accurate calibration and the determination of the lidar overlap factor, which biases WVMR retrieval under 300 m. Instead, we propose the use of a lightweight Pressure-Temperature-Relative Humidity (PTU) sound carried under a simple kite to perform a co-localized sounding. Modern kites indeed combine the advantages of an easy deployment and the possibility of longer, more precise soundings in the low troposphere. After showing that this approach leads to calibration with less than 2% error from 80 m altitude, we validate it against rawindsounding WVMR profiles, with very good agreement at high altitude. We also present further comparisons between the lidar-derived WVMR and the one given by meteorological model reanalyses (AROME, ECMWF) or satellite inversion products (IASI).

Predator versus Prey: Locust Looming-Detector Neuron and Behavioural Responses to Stimuli Representing Attacking Bird Predators

PubMed Central

Santer, Roger D.; Rind, F. Claire; Simmons, Peter J.

2012-01-01

Many arthropods possess escape-triggering neural mechanisms that help them evade predators. These mechanisms are important neuroethological models, but they are rarely investigated using predator-like stimuli because there is often insufficient information on real predator attacks. Locusts possess uniquely identifiable visual neurons (the descending contralateral movement detectors, DCMDs) that are well-studied looming motion detectors. The DCMDs trigger ‘glides’ in flying locusts, which are hypothesised to be appropriate last-ditch responses to the looms of avian predators. To date it has not been possible to study glides in response to stimuli simulating bird attacks because such attacks have not been characterised. We analyse video of wild black kites attacking flying locusts, and estimate kite attack speeds of 10.8±1.4 m/s. We estimate that the loom of a kite’s thorax towards a locust at these speeds should be characterised by a relatively low ratio of half size to speed (l/|v|) in the range 4–17 ms. Peak DCMD spike rate and gliding response occurrence are known to increase as l/|v| decreases for simple looming shapes. Using simulated looming discs, we investigate these trends and show that both DCMD and behavioural responses are strong to stimuli with kite-like l/|v| ratios. Adding wings to looming discs to produce a more realistic stimulus shape did not disrupt the overall relationships of DCMD and gliding occurrence to stimulus l/|v|. However, adding wings to looming discs did slightly reduce high frequency DCMD spike rates in the final stages of object approach, and slightly delay glide initiation. Looming discs with or without wings triggered glides closer to the time of collision as l/|v| declined, and relatively infrequently before collision at very low l/|v|. However, the performance of this system is in line with expectations for a last-ditch escape response. PMID:23209660

Is it feasible to diagnose catheter-related candidemia without catheter withdrawal?

PubMed

Fernández-Cruz, Ana; Martín-Rabadán, Pablo; Suárez-Salas, Marisol; Rojas-Wettig, Loreto; Pérez, María Jesús; Guinea, Jesús; Guembe, María; Peláez, Teresa; Sánchez-Carrillo, Carlos; Bouza, Emilio

2014-07-01

Many bloodstream infections (BSI) in patients with central venous catheters (CVC) are not catheter-related (CR). Assessment of catheter involvement without catheter withdrawal has not been studied in candidemia. We assessed the value of conservative techniques to evaluate catheters as the origin of candidemia in patients with CVC in a prospective cohort study (superficial Gram stain and culture, Kite technique (Gram stain and culture of the first 1 cm blood drawn from the CVC), proportion of positive blood cultures (PPBCs), differential time to positivity (DTP), and minimal time to positivity (MTP)). All catheters were cultured at withdrawal. From June 2008 to January 2012, 22 cases fulfilled the inclusion criteria. CR-candidemia (CRC) was confirmed in 10. Validity values for predicting CRC were: superficial Gram stain (S, 30%; Sp, 81.83%; PPV, 60%; NPV, 56.3%; Ac, 57.1%), superficial cultures (S, 40%; Sp, 75%; PPV, 57.1%; NPV, 60%; Ac, 59.1%), Kite Gram stain (S, 33.3%; Sp, 66.7%; PPV, 50%; NPV, 50%; Ac, 50%), Kite culture (S, 80%; Sp, 66.7%; PPV, 66.7%; NPV, 80%; Ac, 72.7%), PPBC (S, 50%; Sp, 41.7%; PPV, 41.7%; NPV, 50.0%; Ac, 45.5%), DTP (S, 100%; Sp, 33.3%; PPV, 55.6%; NPV, 100%; Ac, 63.6%), and MTTP (S, 70%; Sp, 58.3%; PPV, 58.3%; NPV, 70%; Ac, 63.6%). While combinations of two tests improved sensitivity and NPV, more than two tests did not improve validity values. Classic tests to assess CR-BSI caused by bacteria cannot be reliably used to diagnose CRC. Combinations of tests could be useful, but more and larger studies are required. © The Author 2014. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Wild Birds, Frequent Carriers of Extended-Spectrum β-Lactamase (ESBL) Producing Escherichia coli of CTX-M and SHV-12 Types.

PubMed

Alcalá, Leticia; Alonso, Carla Andrea; Simón, Carmen; González-Esteban, Chabier; Orós, Jesús; Rezusta, Antonio; Ortega, Carmelo; Torres, Carmen

2016-11-01

To get a better insight into the role of birds as reservoirs of extended-spectrum β-lactamase (ESBL) and plasmidic AmpC β-lactamase (pAmpC) Escherichia coli producers, 100 fecal samples belonging to 15 different wild avian species from Northern Spain were analyzed. Cefotaxime-resistant (CTX R ) E. coli isolates were identified in 16 of the 100 tested birds, which corresponded to 9 animal species (Gyps fulvus-griffon vulture, Larus michahellis-yellow-legged gull, Milvus migrans-black kite, Milvus milvus-red kite, Ciconia ciconia-white stork, Sturnus unicolor-spotless starling, Aquila chrysaetos-golden eagle, Cuculus canorus-common cuckoo, Tyto alba-barn owl). Fifteen isolates harbored ESBL or pAmpC-encoding genes (number of isolates): bla SHV-12 (9), bla CTX-M-1 (3), bla CTX-M-14 (2), and bla CMY-2 (1). The last CTX R isolate presented a -42-point-mutation in the chromosomal ampC promoter. Eleven out of 15 ESBL/pAmpC E. coli isolates were multiresistant (most common resistance phenotype: β-lactams-quinolones-tetracycline-sulfamethoxazole/trimethoprim). A plasmid-mediated quinolone resistance determinant (qnrS1) was identified in one E. coli from a barn owl. High genetic diversity was observed among ESBL/pAmpC E. coli isolates, with 12 different sequence types (STs), including several strains of STs frequently detected among human clinical isolates (ST38/D, ST131/B2, ST155/B1, ST10/A). The ST131 isolate belonged to the emergent ciprofloxacin-resistant H30R subclone. This study reveals a high percentage of bird as carriers of ESBL/pAmpC E. coli isolates in Spain, highlighting the elevated rate among storks, kites, and vultures. Wild birds can contribute to the global spread of ESBL/pAmpC-producing E. coli in natural ecosystems.

An Analysis of Effect of Water Resources Constraint on Energy Production in Turkey

DTIC Science & Technology

2012-12-01

wind turbines usually have two or three blades and, because winds above the ground tend to be faster and less turbulent than those near the surface... turbines are mounted on tall towers to capture the most energy. As the blades turn, the central shaft spins a generator to make electricity. Wind ... turbines a placed at sites with strong and steady winds (about 20 km/hour) can economically generate electricity without producing pollutants. Wind

National-Scale Wind Resource Assessment for Power Generation (Presentation)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baring-Gould, E. I.

2013-08-01

This presentation describes the current standards for conducting a national-scale wind resource assessment for power generation, along with the risk/benefit considerations to be considered when beginning a wind resource assessment. The presentation describes changes in turbine technology and viable wind deployment due to more modern turbine technology and taller towers and shows how the Philippines national wind resource assessment evolved over time to reflect changes that arise from updated technologies and taller towers.

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

NASA Astrophysics Data System (ADS)

Jarquin-Laguna, A.

2016-09-01

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

Evaluating the Impacts of Real-Time Pricing on the Cost and Value of Wind Generation

DOE PAGES

Siohansi, Ramteen

2010-05-01

One of the costs associated with integrating wind generation into a power system is the cost of redispatching the system in real-time due to day-ahead wind resource forecast errors. One possible way of reducing these redispatch costs is to introduce demand response in the form of real-time pricing (RTP), which could allow electricity demand to respond to actual real-time wind resource availability using price signals. A day-ahead unit commitment model with day-ahead wind forecasts and a real-time dispatch model with actual wind resource availability is used to estimate system operations in a high wind penetration scenario. System operations are comparedmore » to a perfect foresight benchmark, in which actual wind resource availability is known day-ahead. The results show that wind integration costs with fixed demands can be high, both due to real-time redispatch costs and lost load. It is demonstrated that introducing RTP can reduce redispatch costs and eliminate loss of load events. Finally, social surplus with wind generation and RTP is compared to a system with neither and the results demonstrate that introducing wind and RTP into a market can result in superadditive surplus gains.« less

NREL Triples Previous Estimates of U.S. Wind Power Potential (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The National Renewable Energy Laboratory (NREL) recently released new estimates of the U.S. potential for wind-generated electricity, using advanced wind mapping and validation techniques to triple previous estimates of the size of the nation's wind resources. The new study, conducted by NREL and AWS TruePower, finds that the contiguous 48 states have the potential to generate up to 37 million gigawatt-hours annually. In comparison, the total U.S. electricity generation from all sources was roughly 4 million gigawatt-hours in 2009.

Frequency Regulation and Oscillation Damping Contributions of Variable-Speed Wind Generators in the U.S. Eastern Interconnection (EI)

DOE PAGES

Liu, Yong; Gracia, Jose R,; King, Jr, Thomas J.; ...

2014-05-16

The U.S. Eastern Interconnection (EI) is one of the largest electric power grids in the world and is expected to have difficulties in dealing with frequency regulation and oscillation damping issues caused by the increasing wind power. On the other side, variable-speed wind generators can actively engage in frequency regulation or oscillation damping with supplementary control loops. This paper creates a 5% wind power penetration simulation scenario based on the 16 000-bus EI system dynamic model and developed the user-defined wind electrical control model in PSS (R) E that incorporates additional frequency regulation and oscillation damping control loops. We evaluatedmore » the potential contributions of variable-speed wind generations to the EI system frequency regulation and oscillation damping, and simulation results demonstrate that current and future penetrations of wind power are promising in the EI system frequency regulation and oscillation damping.« less

Anisotropic Solar Wind Sputtering of the Lunar Surface Induced by Crustal Magnetic Anomalies

NASA Technical Reports Server (NTRS)

Poppe, A. R.; Sarantos, M.; Halekas, J. S.; Delory, G. T.; Saito, Y.; Nishino, M.

2014-01-01

The lunar exosphere is generated by several processes each of which generates neutral distributions with different spatial and temporal variability. Solar wind sputtering of the lunar surface is a major process for many regolith-derived species and typically generates neutral distributions with a cosine dependence on solar zenith angle. Complicating this picture are remanent crustal magnetic anomalies on the lunar surface, which decelerate and partially reflect the solar wind before it strikes the surface. We use Kaguya maps of solar wind reflection efficiencies, Lunar Prospector maps of crustal field strengths, and published neutral sputtering yields to calculate anisotropic solar wind sputtering maps. We feed these maps to a Monte Carlo neutral exospheric model to explore three-dimensional exospheric anisotropies and find that significant anisotropies should be present in the neutral exosphere depending on selenographic location and solar wind conditions. Better understanding of solar wind/crustal anomaly interactions could potentially improve our results.

Maximum capacity model of grid-connected multi-wind farms considering static security constraints in electrical grids

NASA Astrophysics Data System (ADS)

Zhou, W.; Qiu, G. Y.; Oodo, S. O.; He, H.

2013-03-01

An increasing interest in wind energy and the advance of related technologies have increased the connection of wind power generation into electrical grids. This paper proposes an optimization model for determining the maximum capacity of wind farms in a power system. In this model, generator power output limits, voltage limits and thermal limits of branches in the grid system were considered in order to limit the steady-state security influence of wind generators on the power system. The optimization model was solved by a nonlinear primal-dual interior-point method. An IEEE-30 bus system with two wind farms was tested through simulation studies, plus an analysis conducted to verify the effectiveness of the proposed model. The results indicated that the model is efficient and reasonable.

Integration of permanent magnet synchronous generator wind turbines into power grid

NASA Astrophysics Data System (ADS)

Abedini, Asghar

The world is seeing an ever-increasing demand for electrical energy. The future growth of electrical power generation needs to be a mix of technologies including fossil fuels, hydro, nuclear, wind, and solar. The federal and state energy agencies have taken several proactive steps to increase the share of renewable energy in the total generated electrical power. In 2005, 11.1% of the total 1060 GW electricity generation capacity was from Renewable Energy Sources (RES) in the US. The power capacity portfolio included 9.2% from hydroelectric, 0.87% from wind, and 0.7% from biomass. Other renewable power capacity included 2.8 GW of geothermal, 0.4 GW of solar thermal, and 0.2 GW of solar PV. Although the share of renewable energy sources is small compared with the total power capacity, they are experiencing a high and steady growth. The US is leading the world in wind energy growth with a 27% increase in 2006 and a projected 26% increase in 2007, according to the American Wind Energy Association (AWEA). The US Department of Energy benchmarked a goal to meet 5% of the nation's energy need by launching the Wind Powering America (WPA) program. Although renewable energy sources have many benefits, their utilization in the electrical grid does not come without cost. The higher penetration of RES has introduced many technical and non-technical challenges, including power quality, reliability, safety and protection, load management, grid interconnections and control, new regulations, and grid operation economics. RES such as wind and PV are also intermittent in nature. The energy from these sources is available as long as there is wind or sunlight. However, these are energies that are abundant in the world and the power generated from these sources is pollution free. Due to high price of foundation of wind farms, employing variable speed wind turbines to maximize the extracted energy from blowing wind is more beneficial. On the other hand, since wind power is intermittent, integrating energy storage systems with wind farms has attracted a lot of attention. These two subjects are addressed in this dissertation in detail. Permanent Magnet Synchronous Generators (PMSG) are used in variable speed wind turbines. In this thesis, the dynamic of the PMSG is investigated and a power electronic converter is designed to integrate the wind turbine to the grid. The risks of PMSG wind turbines such as low voltage ride through and short circuits, are assessed and the methods of mitigating the risks are discussed. In the second section of the thesis, various methods of smoothing wind turbine output power are explained and compared. Two novel methods of output power smoothing are analyzed: Rotor inertia and Super capacitors. The advantages and disadvantages of each method are explained and the dynamic model of each method is developed. The performance of the system is evaluated by simulating the wind turbine system in each method. The concepts of the methods of smoothing wind power can be implemented in other types of wind turbines such as Doubly Fed Induction Generator (DFIG) wind turbines.

Tropospheric Wind Monitoring During Day-of-Launch Operations for National Aeronautics and Space Administration's Space Shuttle Program

NASA Technical Reports Server (NTRS)

Decker, Ryan K.; Leach, Richard

2004-01-01

The Environments Group at the National Aeronautics and Space Administration's Marshall Space Flight Center (NASA/MSFC) monitors the winds aloft at Kennedy Space Center (KSC) during the countdown for all Space Shuttle launches. Assessment of tropospheric winds is used to support the ascent phase of launch. Three systems at KSC are used to generate independent tropospheric wind profiles prior to launch; 1) high resolution Jimsphere balloon system, 2) 50-MHz Doppler Radar Wind Profiler (DRWP) and 3) low resolution radiosonde system. Data generated by the systems are used to assess spatial and temporal wind variability during launch countdown to ensure wind change observed does not violate wind change criteria constraints.

76 FR 47573 - Notice of Effectiveness of Exempt Wholesale Generator Status

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-05

...-000 Sherbino II Wind Farm LLC EG11-87-000 Tanner Street Generation, LLC EG11-88-000 Inversiones E... Wholesale Generator Status Docket Nos. Bayonne Energy Center, LLC EG11-80-000 Long Island Solar Farm, LLC EG11-81-000 Evergreen Gen Lead, LLC EG11-82-000 Alta Wind IV Owner Lessor A EG11-83-000 Alta Wind IV...

FEM Simulation of Small Wind Power Generating System Using PMSG

NASA Astrophysics Data System (ADS)

Kesamaru, Katsumi; Ohno, Yoshihiro; Sonoda, Daisuke

The paper describes a new approach to simulate the small wind power generating systems using PMSG, in which the output is connected to constant resistive load, such as heaters, through the rectifier and the dc chopper. The dynamics of the wind power generating system is presented, and it is shown by simulation results that this approach is useful for system dynamics, such as starting phenomena.

Mod-5A wind turbine generator program design report. Volume 2: Conceptual and preliminary design, book 2

NASA Technical Reports Server (NTRS)

1984-01-01

The design, development and analysis of the 7.3 MW MOD-5A wind tunnel generator is documented. There are four volumes. In Volume 2, book 2 the requirements and criteria for the design are presented. The development tests, which determined or characterized many of the materials and components of the wind turbine generator, are described.

77 FR 48138 - Topaz Solar Farms LLC; High Plains Ranch II, LLC; Bethel Wind Energy LLC; Rippey Wind Energy LLC...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-13

... Ranch II, LLC; Bethel Wind Energy LLC; Rippey Wind Energy LLC; Pacific Wind, LLC; Colorado Highlands Wind, LLC; Shooting Star Wind Project, LLC; Notice of Effectiveness of Exempt Wholesale Generator or...

Background and system description of the Mod 1 wind turbine generator

NASA Technical Reports Server (NTRS)

Ernst, E. H.

1978-01-01

The Mod-1 wind turbine considered is a large utility-class machine, operating in the high wind regime, which has the potential for generation of utility grade power at costs competitive with other alternative energy sources. A Mod-1 wind turbine generator (WTG) description is presented, taking into account the two variable-pitch steel blades of the rotor, the drive train, power generation/control, the Nacelle structure, and the yaw drive. The major surface elements of the WTG are the ground enclosure, the back-up battery system, the step-up transformer, elements of the data system, cabling, area lighting, and tower foundation. The final system weight (rotor, Nacelle, and tower) is expected to be about 650,000 pounds. The WTG will be capable of delivering 1800 kW to the utility grid in a wind-speed above 25 mph.

Status of wind-energy conversion

NASA Technical Reports Server (NTRS)

Thomas, R. L.; Savino, J. M.

1973-01-01

The utilization of wind energy is technically feasible as evidenced by the many past demonstrations of wind generators. The cost of energy from the wind has been high compared to fossil fuel systems; a sustained development effort is needed to obtain economical systems. The variability of the wind makes it an unreliable source on a short term basis. However, the effects of this variability can be reduced by storage systems or connecting wind generators to: (1) fossil fuel systems; (2) hydroelectric systems; or (3) dispersing them throughout a large grid network. Wind energy appears to have the potential to meet a significant amount of our energy needs.

A solid-state controller for a wind-driven slip-ring induction generator

NASA Astrophysics Data System (ADS)

Velayudhan, C.; Bundell, J. H.; Leary, B. G.

1984-08-01

The three-phase induction generator appears to become the preferred choice for wind-powered systems operated in parallel with existing power systems. A problem arises in connection with the useful operating speed range of the squirrel-cage machine, which is relatively narrow, as, for instance, in the range from 1 to 1.15. Efficient extraction of energy from a wind turbine, on the other hand, requires a speed range, perhaps as large as 1 to 3. One approach for 'matching' the generator to the turbine for the extraction of maximum power at any usable wind speed involves the use of a slip-ring induction machine. The power demand of the slip-ring machine can be matched to the available output from the wind turbine by modifying the speed-torque characteristics of the generator. A description is presented of a simple electronic rotor resistance controller which can optimize the power taken from a wind turbine over the full speed range.

Level-crossing statistics of the horizontal wind speed in the planetary surface boundary layer

NASA Astrophysics Data System (ADS)

Edwards, Paul J.; Hurst, Robert B.

2001-09-01

The probability density of the times for which the horizontal wind remains above or below a given threshold speed is of some interest in the fields of renewable energy generation and pollutant dispersal. However there appear to be no analytic or conceptual models which account for the observed power law form of the distribution of these episode lengths over a range of over three decades, from a few tens of seconds to a day or more. We reanalyze high resolution wind data and demonstrate the fractal character of the point process generated by the wind speed level crossings. We simulate the fluctuating wind speed by a Markov process which approximates the characteristics of the real (non-Markovian) wind and successfully generates a power law distribution of episode lengths. However, fundamental questions concerning the physical basis for this behavior and the connection between the properties of a continuous-time stochastic process and the fractal statistics of the point process generated by its level crossings remain unanswered.

76 FR 76397 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-07

..., Dry Lake Wind Power, LLC, Dry Lake Wind Power II LLC, Elk River Windfarm, LLC, Elm Creek Wind, LLC..., Flying Cloud Power Partners, LLC, Hardscrabble Wind Power LLC, Hay Canyon Wind LLC, Juniper Canyon Wind Power LLC, Klamath Energy LLC, Klamath Generation LLC, Klondike Wind Power LLC, Klondike Wind Power II...

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

NASA Astrophysics Data System (ADS)

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

2017-01-01

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

A 20-KW Wind Energy Conversion System (WECS) at the Marine Corps Air Station, Kaneohe, Hawaii.

DTIC Science & Technology

1983-01-01

of propellers and that vertical-axis wind turbines would be more efficient. Several turbines such as the Darrieus and gyro-mill, of this type are... wind turbines , wind systems siting, alternate energy systems, remote site power generation. 20 ABSTRACT (Con!,,u,. - r r... .. do I(3 lI - d #,d e...Corps Air Station (MCAS) Kaneohe Bay, Hawaii. The wind turbine generator chosen for the evaluation was a horizontal-axis-propeller- downwind rotor

Influence of winding construction on starter-generator thermal processes

NASA Astrophysics Data System (ADS)

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

2018-01-01

Dynamic processes in starter-generators features high winding are overcurrent. It can lead to insulation overheating and fault operation mode. For hybrid and electric vehicles, new high efficiency construction of induction machines windings is proposed. Stator thermal processes need be considered in the most difficult operation modes. The article describes construction features of new compact stator windings, electromagnetic and thermal models of processes in stator windings and explains the influence of innovative construction on thermal processes. Models are based on finite element method.

76 FR 65716 - Notice of Effectiveness of Exempt Wholesale Generator Status

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-24

... South, LLC EG11-104-000 Gratiot County Wind LLC EG11-105-000 Invenergy Wind Development Michigan LLC EG11-106-000 Trinity Hills Wind Farm LLC EG11-107-000 High Plains Ranch II, LLC EG11-108-000 Double ``C... Wholesale Generator Status Docket No. Michigan Wind 2, LLC EG11-100-000 Bishop Hill Energy LLC EG11-101-000...

78 FR 57173 - Notice of Availability of the Record of Decision for the Mohave County Wind Farm Project, Mohave...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-17

... generated by the Project. The approved Project includes up to 243 wind turbine generators and associated..., operation, maintenance, and decommissioning of the Project to BP Wind Energy; and for the BLM to issue a ROW...; AZA32315AA] Notice of Availability of the Record of Decision for the Mohave County Wind Farm Project, Mohave...

77 FR 35423 - Notice of Availability of the Record of Decision for the Ocotillo Express LLC's Ocotillo Wind...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-13

... as originally proposed would have consisted of 155 wind turbines (1.6 to 3.0 MW each) on 12,436 acres... the Refined Project, which involves the construction and operation of 112 wind turbines at the project... of the wind generation facility consisting of: up to 112 turbines with a generating capacity of 315...

The General Electric MOD-1 wind turbine generator program

NASA Technical Reports Server (NTRS)

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

1979-01-01

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

Superconducting light generator for large offshore wind turbines

NASA Astrophysics Data System (ADS)

Sanz, S.; Arlaban, T.; Manzanas, R.; Tropeano, M.; Funke, R.; Kováč, P.; Yang, Y.; Neumann, H.; Mondesert, B.

2014-05-01

Offshore wind market demands higher power rate and reliable turbines in order to optimize capital and operational cost. These requests are difficult to overcome with conventional generator technologies due to a significant weight and cost increase with the scaling up. Thus superconducting materials appears as a prominent solution for wind generators, based on their capacity to held high current densities with very small losses, which permits to efficiently replace copper conductors mainly in the rotor field coils. However the state-of-the-art superconducting generator concepts still seem to be expensive and technically challenging for the marine environment. This paper describes a 10 MW class novel direct drive superconducting generator, based on MgB2 wires and a modular cryogen free cooling system, which has been specifically designed for the offshore wind industry needs.

76 FR 72402 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-23

...-772-003. Applicants: ExxonMobil Baton Rouge Complex. Description: ExxonMobil Entities submits their... Bethlehem, LLC, Calpine Mid-Atlantic Generation, LLC, Calpine Mid Merit, LLC, Calpine New Jersey Generation... City Generation, L.P., Forward WindPower, LLC, Lookout WindPower, LLC, Midwest Generation, LLC...

Indexed semi-Markov process for wind speed modeling.

NASA Astrophysics Data System (ADS)

Petroni, F.; D'Amico, G.; Prattico, F.

2012-04-01

The increasing interest in renewable energy leads scientific research to find a better way to recover most of the available energy. Particularly, the maximum energy recoverable from wind is equal to 59.3% of that available (Betz law) at a specific pitch angle and when the ratio between the wind speed in output and in input is equal to 1/3. The pitch angle is the angle formed between the airfoil of the blade of the wind turbine and the wind direction. Old turbine and a lot of that actually marketed, in fact, have always the same invariant geometry of the airfoil. This causes that wind turbines will work with an efficiency that is lower than 59.3%. New generation wind turbines, instead, have a system to variate the pitch angle by rotating the blades. This system able the wind turbines to recover, at different wind speed, always the maximum energy, working in Betz limit at different speed ratios. A powerful system control of the pitch angle allows the wind turbine to recover better the energy in transient regime. A good stochastic model for wind speed is then needed to help both the optimization of turbine design and to assist the system control to predict the value of the wind speed to positioning the blades quickly and correctly. The possibility to have synthetic data of wind speed is a powerful instrument to assist designer to verify the structures of the wind turbines or to estimate the energy recoverable from a specific site. To generate synthetic data, Markov chains of first or higher order are often used [1,2,3]. In particular in [1] is presented a comparison between a first-order Markov chain and a second-order Markov chain. A similar work, but only for the first-order Markov chain, is conduced by [2], presenting the probability transition matrix and comparing the energy spectral density and autocorrelation of real and synthetic wind speed data. A tentative to modeling and to join speed and direction of wind is presented in [3], by using two models, first-order Markov chain with different number of states, and Weibull distribution. All this model use Markov chains to generate synthetic wind speed time series but the search for a better model is still open. Approaching this issue, we applied new models which are generalization of Markov models. More precisely we applied semi-Markov models to generate synthetic wind speed time series. In a previous work we proposed different semi-Markov models, showing their ability to reproduce the autocorrelation structures of wind speed data. In that paper we showed also that the autocorrelation is higher with respect to the Markov model. Unfortunately this autocorrelation was still too small compared to the empirical one. In order to overcome the problem of low autocorrelation, in this paper we propose an indexed semi-Markov model. More precisely we assume that wind speed is described by a discrete time homogeneous semi-Markov process. We introduce a memory index which takes into account the periods of different wind activities. With this model the statistical characteristics of wind speed are faithfully reproduced. The wind is a very unstable phenomenon characterized by a sequence of lulls and sustained speeds, and a good wind generator must be able to reproduce such sequences. To check the validity of the predictive semi-Markovian model, the persistence of synthetic winds were calculated, then averaged and computed. The model is used to generate synthetic time series for wind speed by means of Monte Carlo simulations and the time lagged autocorrelation is used to compare statistical properties of the proposed models with those of real data and also with a time series generated though a simple Markov chain. [1] A. Shamshad, M.A. Bawadi, W.M.W. Wan Hussin, T.A. Majid, S.A.M. Sanusi, First and second order Markov chain models for synthetic generation of wind speed time series, Energy 30 (2005) 693-708. [2] H. Nfaoui, H. Essiarab, A.A.M. Sayigh, A stochastic Markov chain model for simulating wind speed time series at Tangiers, Morocco, Renewable Energy 29 (2004) 1407-1418. [3] F. Youcef Ettoumi, H. Sauvageot, A.-E.-H. Adane, Statistical bivariate modeling of wind using first-order Markov chain and Weibull distribution, Renewable Energy 28 (2003) 1787-1802.

Generation of Wind Waves in the Persian Gulf: A Numerical Investigation

NASA Astrophysics Data System (ADS)

Liao, Y.; Kaihatu, J. M.

2010-12-01

The Persian Gulf is a long shallow basin located between the Arabian Peninsula and Iran. Wind-wave generation processes in the region are often affected by the shamal, a strong wind caused by the passage of cold fronts over the mountains of Turkey and Kurdistan. This can set up sudden energetic wind seas, hampering marine traffic. It is not immediately clear whether present wind-wave models can predict this intense, short-term growth and evolution under these conditions. Furthermore, few wave measurements or models studies have been performed in this area. In advance of a wind-wave generation experiment to be conducted off the Qatar coast, we performed a climatological study of the wind wave environment in the Persian Gulf. Using the SWAN wave model as a baseline of the state of the art, five years (2004-2008)of wind field model hindcasts from COAMPS are used as forcing.To investigate the sensitivity of the results to bathymetry, the climatological analysis was run twice more, with refraction or wave breaking deactivated, in turn. The results do not show significant differences with and without refraction, which implies the wind-wave process in Persian Gulf is less dominated by the variation of bathymetry. However the results show that a large amount of wave is dissipated by wave breaking. Wide, flat and shallow bathymetry in Persian Gulf results in a long-fetch scenario, particularly for waves arriving from the northwest. It implies that long period wind-generated waves can be fully generated in this region. Wave height is therefore fully grown by the long-fetch condition, so as to lead in higher possibility of wave breaking and energy dissipation.

Wind power: The new energy policy 1

NASA Astrophysics Data System (ADS)

1991-10-01

Increasing use of renewable energy sources is an important aspect of the new energy policy of the State government of Schleswig-Holstein. Technical and industrial innovation are involved. By expanding and developing these regionally available inexhaustible energy sources to generate electricity and heat, we are contributing to environmental protection and helping to reduce adverse affects on the climate. We are also taking our limited resources into account and expanding energy generation in a logical manner. Wind energy is the most attractive renewable energy source for Schleswig-Holstein because our State is well known for its strong winds and constant fresh breeze. For this reason the State government has made expansion of wind energy one of its primary areas of emphasis. The goals of our promotion measures includes ongoing technical and engineering development of wind energy facilities, increasing the level of use of the wind, and increasing the percentage of wind energy used for power generation. This brochure is intended to demonstrate the significance and possibilities of wind energy for our State, to outline the legal requirements for erecting wind energy facilities, and to explain the many promotion measures. It represents a favorable breeze for wind.

Electrostatic Solitary Waves in the Solar Wind: Evidence for Instability at Solar Wind Current Sheets

NASA Technical Reports Server (NTRS)

Malaspina, David M.; Newman, David L.; Wilson, Lynn Bruce; Goetz, Keith; Kellogg, Paul J.; Kerstin, Kris

2013-01-01

A strong spatial association between bipolar electrostatic solitary waves (ESWs) and magnetic current sheets (CSs) in the solar wind is reported here for the first time. This association requires that the plasma instabilities (e.g., Buneman, electron two stream) which generate ESWs are preferentially localized to solar wind CSs. Distributions of CS properties (including shear angle, thickness, solar wind speed, and vector magnetic field change) are examined for differences between CSs associated with ESWs and randomly chosen CSs. Possible mechanisms for producing ESW-generating instabilities at solar wind CSs are considered, including magnetic reconnection.

Electric Grid Expansion Planning with High Levels of Variable Generation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hadley, Stanton W.; You, Shutang; Shankar, Mallikarjun

2016-02-01

Renewables are taking a large proportion of generation capacity in U.S. power grids. As their randomness has increasing influence on power system operation, it is necessary to consider their impact on system expansion planning. To this end, this project studies the generation and transmission expansion co-optimization problem of the US Eastern Interconnection (EI) power grid with a high wind power penetration rate. In this project, the generation and transmission expansion problem for the EI system is modeled as a mixed-integer programming (MIP) problem. This study analyzed a time series creation method to capture the diversity of load and wind powermore » across balancing regions in the EI system. The obtained time series can be easily introduced into the MIP co-optimization problem and then solved robustly through available MIP solvers. Simulation results show that the proposed time series generation method and the expansion co-optimization model and can improve the expansion result significantly after considering the diversity of wind and load across EI regions. The improved expansion plan that combines generation and transmission will aid system planners and policy makers to maximize the social welfare. This study shows that modelling load and wind variations and diversities across balancing regions will produce significantly different expansion result compared with former studies. For example, if wind is modeled in more details (by increasing the number of wind output levels) so that more wind blocks are considered in expansion planning, transmission expansion will be larger and the expansion timing will be earlier. Regarding generation expansion, more wind scenarios will slightly reduce wind generation expansion in the EI system and increase the expansion of other generation such as gas. Also, adopting detailed wind scenarios will reveal that it may be uneconomic to expand transmission networks for transmitting a large amount of wind power through a long distance in the EI system. Incorporating more details of renewables in expansion planning will inevitably increase the computational burden. Therefore, high performance computing (HPC) techniques are urgently needed for power system operation and planning optimization. As a scoping study task, this project tested some preliminary parallel computation techniques such as breaking down the simulation task into several sub-tasks based on chronology splitting or sample splitting, and then assigning these sub-tasks to different cores. Testing results show significant time reduction when a simulation task is split into several sub-tasks for parallel execution.« less

Army Communicator. Volume 30, Number 3, Summer 2005

DTIC Science & Technology

2005-01-01

radio is an IP phone. coffee runner for the brigade signal officer and need to understand the Signal commander’s role in the big picture. We as...111th (center front), LTC Kite , 54th BN CDR (center back), PV2 Harrington, Guidon Bearer A/280th (center front), 1SG Fields, A/280th (right back

Blindness to Curvature and Blindness to Illusory Curvature.

PubMed

Bertamini, Marco; Kitaoka, Akiyoshi

2018-01-01

We compare two versions of two known phenomena, the Curvature blindness and the Kite mesh illusions, to highlight how similar manipulations lead to blindness to curvature and blindness to illusory curvature, respectively. The critical factor is a change in luminance polarity; this factor interferes with the computation of curvature along the contour, for both real and illusory curvature.

Kite Aerial Photography as a Tool for Remote Sensing

ERIC Educational Resources Information Center

Sallee, Jeff; Meier, Lesley R.

2010-01-01

As humans, we perform remote sensing nearly all the time. This is because we acquire most of our information about our surroundings through the senses of sight and hearing. Whether viewed by the unenhanced eye or a military satellite, remote sensing is observing objects from a distance. With our current technology, remote sensing has become a part…

Mod-5A wind turbine generator program design report. Volume 4: Drawings and specifications, book 5

NASA Technical Reports Server (NTRS)

1984-01-01

The design, development and analysis of the 7.3 MW MOD-5A wind turbine generator is documented. There are four volumes. This volume contains the drawings and specifications that were developed in preparation for building the MOD-5A wind turbine generator. Detail drawings of several assemblies and subassemblies are given. This is the fifth book of volume 4.

Effects of wind energy generation and white-nose syndrome on the viability of the Indiana bat

PubMed Central

Thogmartin, Wayne E.; Diffendorfer, Jay E.; Russell, Robin E.; Szymanski, Jennifer A.

2016-01-01

Wind energy generation holds the potential to adversely affect wildlife populations. Species-wide effects are difficult to study and few, if any, studies examine effects of wind energy generation on any species across its entire range. One species that may be affected by wind energy generation is the endangered Indiana bat (Myotis sodalis), which is found in the eastern and midwestern United States. In addition to mortality from wind energy generation, the species also faces range-wide threats from the emerging infectious fungal disease, white-nose syndrome (WNS). White-nose syndrome, caused by Pseudogymnoascus destructans, disturbs hibernating bats leading to high levels of mortality. We used a spatially explicit full-annual-cycle model to investigate how wind turbine mortality and WNS may singly and then together affect population dynamics of this species. In the simulation, wind turbine mortality impacted the metapopulation dynamics of the species by causing extirpation of some of the smaller winter colonies. In general, effects of wind turbines were localized and focused on specific spatial subpopulations. Conversely, WNS had a depressive effect on the species across its range. Wind turbine mortality interacted with WNS and together these stressors had a larger impact than would be expected from either alone, principally because these stressors together act to reduce species abundance across the spectrum of population sizes. Our findings illustrate the importance of not only prioritizing the protection of large winter colonies as is currently done, but also of protecting metapopulation dynamics and migratory connectivity. PMID:28028486

An integrated modeling method for wind turbines

NASA Astrophysics Data System (ADS)

Fadaeinedjad, Roohollah

To study the interaction of the electrical, mechanical, and aerodynamic aspects of a wind turbine, a detailed model that considers all these aspects must be used. A drawback of many studies in the area of wind turbine simulation is that either a very simple mechanical model is used with a detailed electrical model, or vice versa. Hence the interactions between electrical and mechanical aspects of wind turbine operation are not accurately taken into account. In this research, it will be shown that a combination of different simulation packages, namely TurbSim, FAST, and Simulink can be used to model the aerodynamic, mechanical, and electrical aspects of a wind turbine in detail. In this thesis, after a review of some wind turbine concepts and software tools, a simulation structure is proposed for studying wind turbines that integrates the mechanical and electrical components of a wind energy conversion device. Based on the simulation structure, a comprehensive model for a three-bladed variable speed wind turbine with doubly-fed induction generator is developed. Using the model, the impact of a voltage sag on the wind turbine tower vibration is investigated under various operating conditions such as power system short circuit level, mechanical parameters, and wind turbine operating conditions. It is shown how an electrical disturbance can cause more sustainable tower vibrations under high speed and turbulent wind conditions, which may disrupt the operation of pitch control system. A similar simulation structure is used to model a two-bladed fixed speed wind turbine with an induction generator. An extension of the concept is introduced by adding a diesel generator system. The model is utilized to study the impact of the aeroelastic aspects of wind turbine (i.e. tower shadow, wind shears, yaw error, turbulence, and mechanical vibrations) on the power quality of a stand-alone wind-diesel system. Furthermore, an IEEE standard flickermeter model is implemented in a Simulink environment to study the flicker contribution of the wind turbine in the wind-diesel system. By using a new wind power plant representation method, a large wind farm (consisting of 96 fixed speed wind turbines) is modelled to study the power quality of wind power system. The flicker contribution of wind farm is also studied with different wind turbine numbers, using the flickermeter model. Keywords. Simulink, FAST, TurbSim, AreoDyn, wind energy, doubly-fed induction generator, variable speed wind turbine, voltage sag, tower vibration, power quality, flicker, fixed speed wind turbine, wind shear, tower shadow, and yaw error.

Performance characteristics of aerodynamically optimum turbines for wind energy generators

NASA Technical Reports Server (NTRS)

Rohrbach, C.; Worobel, R.

1975-01-01

This paper presents a brief discussion of the aerodynamic methodology for wind energy generator turbines, an approach to the design of aerodynamically optimum wind turbines covering a broad range of design parameters, some insight on the effect on performance of nonoptimum blade shapes which may represent lower fabrication costs, the annual wind turbine energy for a family of optimum wind turbines, and areas of needed research. On the basis of the investigation, it is concluded that optimum wind turbines show high performance over a wide range of design velocity ratios; that structural requirements impose constraints on blade geometry; that variable pitch wind turbines provide excellent power regulation and that annual energy output is insensitive to design rpm and solidity of optimum wind turbines.

Investigation of a generator system for generating electrical power, to supply directly to the public network, using a windmill

NASA Technical Reports Server (NTRS)

Tromp, C.

1979-01-01

A windpowered generator system is described which uses a windmill to convert mechanical energy to electrical energy for a three phase (network) voltage of constant amplitude and frequency. The generator system controls the windmill by the number of revolutions so that the power drawn from the wind for a given wind velocity is maximum. A generator revolution which is proportional to wind velocity is achieved. The stator of the generator is linked directly to the network and a feed converter at the rotor takes care of constant voltage and frequency at the stator.

Brushless DC motor control system responsive to control signals generated by a computer or the like

NASA Technical Reports Server (NTRS)

Packard, D. T. (Inventor)

1985-01-01

A control system for a brushless DC motor responsive to digital control signals is disclosed. The motor includes a multiphase wound stator and a permanent magnet rotor. The motor is arranged so that each phase winding, when energized from a DC source, will drive the rotor through a predetermined angular position or step. A commutation signal generator responsive to the shaft position provides a commutation signal for each winding. A programmable control signal generator such as a computer or microprocessor produces individual digital control signals for each phase winding. The control signals and commutation signals associated with each winding are applied to an AND gate for that phase winding. Each gate controls a switch connected in series with the associated phase winding and the DC source so that each phase winding is energized only when the commutation signal and the control signal associated with that phase winding are present. The motor shaft may be advanced one step at a time to a desired position by applying a predetermined number of control signals in the proper sequence to the AND gates and the torque generated by the motor be regulated by applying a separate control signal and each AND gate which is pulse width modulated to control the total time that each switch connects its associated winding to the DC source during each commutation period.

Brushless DC motor control system responsive to control signals generated by a computer or the like

NASA Technical Reports Server (NTRS)

Packard, Douglas T. (Inventor); Schmitt, Donald E. (Inventor)

1987-01-01

A control system for a brushless DC motor responsive to digital control signals is disclosed. The motor includes a multiphase wound stator and a permanent magnet rotor. The rotor is arranged so that each phase winding, when energized from a DC source, will drive the rotor through a predetermined angular position or step. A commutation signal generator responsive to the shaft position provides a commutation signal for each winding. A programmable control signal generator such as a computer or microprocessor produces individual digital control signals for each phase winding. The control signals and commutation signals associated with each winding are applied to an AND gate for that phase winding. Each gate controls a switch connected in series with the associated phase winding and the DC source so that each phase winding is energized only when the commutation signal and the control signal associated with that phase winding are present. The motor shaft may be advanced one step at a time to a desired position by applying a predetermined number of control signals in the proper sequence to the AND gates and the torque generated by the motor may be regulated by applying a separate control signal to each AND gate which is pulse width modulated to control the total time that each switch connects its associated winding to the DC source during each commutation period.

Compensation for Harmonic Currents and Reactive Power in Wind Power Generation System using PWM Inverter

NASA Astrophysics Data System (ADS)

Shinohara, Katsuji; Shinhatsubo, Kurato; Iimori, Kenichi; Yamamoto, Kichiro; Saruban, Takamichi; Yamaemori, Takahiro

In recent year, consciousness of environmental problems is enhancing, and the price of the electric power purchased by an electric power company is established expensive for the power plant utilizing the natural energy. So, the introduction of the wind power generation is promoted in Japan. Generally, squirrel-cage induction machines are widely used as a generator in wind power generation system because of its small size, lightweight and low-cost. However, the induction machines do not have a source of excitation. Thus, it causes the inrush currents and the instantaneous voltage drop when the generator is directly connected to a power grid. To reduce the inrush currents, an AC power regulator is used. Wind power generations are frequently connected to and disconnected from the power grid. However, when the inrush currents are reduced, harmonic currents are caused by phase control of the AC power regulator. And the phase control of AC power regulator cannot control the power factor. Therefore, we propose the use of the AC power regulator to compensate for the harmonic currents and reactive power in the wind power generation system, and demonstrate the validity of its system by simulated and experimental results.

Analysis of the electrical harmonic characteristics of a slip recovery variable speed generating system for wind turbine applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herrera, J.I.; Reddoch, T.W.

1988-02-01

Variable speed electric generating technology can enhance the general use of wind energy in electric utility applications. This enhancement results from two characteristic properties of variable speed wind turbine generators: an improvement in drive train damping characteristics, which results in reduced structural loading on the entire wind turbine system, and an improvement in the overall efficiency by using a more sophisticated electrical generator. Electronic converter systems are the focus of this investigation -- in particular, the properties of a wound-rotor induction generator with the slip recovery system and direct-current link converter. Experience with solid-state converter systems in large wind turbinesmore » is extremely limited. This report presents measurements of electrical performances of the slip recovery system and is limited to the terminal characteristics of the system. Variable speed generating systems working effectively in utility applications will require a satisfactory interface between the turbine/generator pair and the utility network. The electrical testing described herein focuses largely on the interface characteristics of the generating system. A MOD-O wind turbine was connected to a very strong system; thus, the voltage distortion was low and the total harmonic distortion in the utility voltage was less than 3% (within the 5% limit required by most utilities). The largest voltage component of a frequency below 60 Hz was 40 dB down from the 60-Hz< component. 8 refs., 14 figs., 8 tabs.« less

Colorado Public Utility Commission's Xcel Wind Decision

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lehr, R. L.; Nielsen, J.; Andrews, S.

2001-09-20

In early 2001 the Colorado Public Utility Commission ordered Xcel Energy to undertake good faith negotiations for a wind plant as part of the utility's integrated resource plan. This paper summarizes the key points of the PUC decision, which addressed the wind plant's projected impact on generation cost and ancillary services. The PUC concluded that the wind plant would cost less than new gas-fired generation under reasonable gas cost projections.

76 FR 81926 - Notice of Effectiveness of Exempt Wholesale Generator Status

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-29

... Renewables, LLC EG11-126-000 Invenergy Illinois Solar I LLC EG11-127-000 Record Hill Wind LLC EG11-128-000 Vasco Winds, LLC EG11-129-000 NexEra Energy Montezuma II Wind, LLC EG11-130-000 Richard-Stryker Generation LLC EG11-131-000 Pioneer Trail Wind Farm, LLC EG11-132-000 GSG 6, LLC EG11-133-000 Take notice...

The Effects of Wind and Surfactants on Mechanically Generated Spilling Breakers

NASA Astrophysics Data System (ADS)

Liu, X.; Diorio, J. D.; Duncan, J. H.

2007-11-01

The effects of both wind and surfactants on mechanically generated weakly spilling breakers are explored in a wind wave tank that is 11.8 m long, 1.15 m wide and 1.8 m high (1.0 m of water). A wave maker, which resides at the upwind end of the tank, is used to generate the breakers via a dispersive focusing method with a central wave packet frequency of 1.15 Hz. Low wind speeds (less than 3.0 m/s) are used to minimize the effect of short-wavelength wind-generated waves on the breakers. The profiles of the spilling breakers along the center plane of the tank are measured with an LIF technique that utilizes a high-speed digital movie camera. Measurements are performed with clean water and water mixed with various concentrations of Triton X-100, a soluble surfactant. It is found that the capillary waves/bulge patterns found in the initial stages of spilling breakers are dramatically affected by wind and surfactants. The size of bulge increases with the wind speed while the capillary waves are kept nearly the same. In the presence of surfactants and wind, both the amplitude and number of capillary waves are reduced and the slope of the front face of the wave increases.

75 FR 27549 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-17

... Numbers: EG10-33-000. Applicants: Meadow Lake Wind Farm III LLC. Description: Self-Certification of exempt wholesale generator status of Meadow Lake Wind Farm III LLC. Filed Date: 04/20/2010. Accession Number.... Applicants: Meadow Lake Wind Farm IV LLC. Description: Self-Certification of exempt wholesale generator...

NEW VERSATILE AEROSOL GENERATION SYSTEM DEVELOPED FOR USE IN A LARGE WIND TUNNEL

EPA Science Inventory

A new aerosol generation system was developed to accommodate a variety of research activities performed within a large wind tunnel. Because many of the velocity measurements are taken in the wind tunnel with a laser Doppler anemometer (LDA), it is necessary to maintain an aero...

78 FR 61942 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-07

... filings: Docket Numbers: EG13-63-000. Applicants: Mountain Wind Power, LLC. Description: Notice Of Self-Certification Of Exempt Wholesale Generator Status Of Mountain Wind Power, LLC. Filed Date: 9/26/13. Accession...: Mountain Wind Power, LLC. Description: Notice Of Self-Certification Of Exempt Wholesale Generator Status Of...

The Oregon State University wind studies. [economic feasibility of windpowered generators

NASA Technical Reports Server (NTRS)

Wilson, R. E.

1973-01-01

The economic feasibility of commercial use of wind generated power in selected areas of Oregon is assessed. A number of machines for generating power have been examined. These include the Savonius rotor, translators, conventional wind turbines, the circulation controlled rotor and the vertical axis winged turbine. Of these machines, the conventional wind turbine and the vertical axis winged turbine show the greatest promise on the basis of the power developed per unit of rotor blade area. Attention has been focused on the structural and fatigue analysis of rotors since the economics of rotary winged, wind generated power depends upon low cost, long lifetime rotors. Analysis of energy storage systems and tower design has also been undertaken. An economic means of energy storage has not been found to date. Tower design studies have produced cost estimates that are in general agreement with the cost of the updated Putnam 110-foot tower.

Generation and Validation of Spatial Distribution of Hourly Wind Speed Time-Series using Machine Learning

NASA Astrophysics Data System (ADS)

Veronesi, F.; Grassi, S.

2016-09-01

Wind resource assessment is a key aspect of wind farm planning since it allows to estimate the long term electricity production. Moreover, wind speed time-series at high resolution are helpful to estimate the temporal changes of the electricity generation and indispensable to design stand-alone systems, which are affected by the mismatch of supply and demand. In this work, we present a new generalized statistical methodology to generate the spatial distribution of wind speed time-series, using Switzerland as a case study. This research is based upon a machine learning model and demonstrates that statistical wind resource assessment can successfully be used for estimating wind speed time-series. In fact, this method is able to obtain reliable wind speed estimates and propagate all the sources of uncertainty (from the measurements to the mapping process) in an efficient way, i.e. minimizing computational time and load. This allows not only an accurate estimation, but the creation of precise confidence intervals to map the stochasticity of the wind resource for a particular site. The validation shows that machine learning can minimize the bias of the wind speed hourly estimates. Moreover, for each mapped location this method delivers not only the mean wind speed, but also its confidence interval, which are crucial data for planners.

Grid Integration Research | Wind | NREL

Science.gov Websites

-generated simulation of a wind turbine. Wind Power Plant Modeling and Simulation Engineers at the National computer-aided engineering tool, FAST, as well as their wind power plant simulation tool, Wind-Plant

76 FR 46284 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-02

... Holdings LLC, Dillon Wind LLC, Dry Lake Wind Power, LLC, Dry Lake Wind Power II LLC, Elk River Windfarm... Rock Windpower II LLC, Flying Cloud Power Partners, LLC, Hardscrabble Wind Power LLC, Hay Canyon Wind LLC, Juniper Canyon Wind Power LLC, Klamath Energy LLC, Klamath Generation LLC, Klondike Wind Power...

Operational results for the experimental DOE/NASA Mod-OA wind turbine project

NASA Astrophysics Data System (ADS)

Shaltens, R. K.; Birchenough, A. G.

The Mod-OA wind turbine project which was to gain early experience in the operation of large wind turbines in a utility environment is discussed. The Mod-OA wind turbines were a first generation design, and even though not cost effective, the operating experience and performance characteristics had a significant effect on the design and development of the second and third generation machines. The Mod-OA machines were modified as a result of the operational experience, particularly the blade development and control system strategy. The results of study to investigate the interaction of a Mod-OA wind turbine with an isolated diesel generation system are discussed. The machine configuration, its advantages and disadvantages and the machine performance and availability are discussed.

Operational results for the experimental DOE/NASA Mod-OA wind turbine project

NASA Technical Reports Server (NTRS)

Shaltens, R. K.; Birchenough, A. G.

1983-01-01

The Mod-OA wind turbine project which was to gain early experience in the operation of large wind turbines in a utility environment is discussed. The Mod-OA wind turbines were a first generation design, and even though not cost effective, the operating experience and performance characteristics had a significant effect on the design and development of the second and third generation machines. The Mod-OA machines were modified as a result of the operational experience, particularly the blade development and control system strategy. The results of study to investigate the interaction of a Mod-OA wind turbine with an isolated diesel generation system are discussed. The machine configuration, its advantages and disadvantages and the machine performance and availability are discussed.

Flexible reserve markets for wind integration

NASA Astrophysics Data System (ADS)

Fernandez, Alisha R.

The increased interconnection of variable generation has motivated the use of improved forecasting to more accurately predict future production with the purpose to lower total system costs for balancing when the expected output exceeds or falls short of the actual output. Forecasts are imperfect, and the forecast errors associated with utility-scale generation from variable generators need new balancing capabilities that cannot be handled by existing ancillary services. Our work focuses on strategies for integrating large amounts of wind generation under the flex reserve market, a market that would called upon for short-term energy services during an under or oversupply of wind generation to maintain electric grid reliability. The flex reserve market would be utilized for time intervals that fall in-between the current ancillary services markets that would be longer than second-to-second energy services for maintaining system frequency and shorter than reserve capacity services that are called upon for several minutes up to an hour during an unexpected contingency on the grid. In our work, the wind operator would access the flex reserve market as an energy service to correct for unanticipated forecast errors, akin to paying the generators participating in the market to increase generation during a shortfall or paying the other generators to decrease generation during an excess of wind generation. Such a market does not currently exist in the Mid-Atlantic United States. The Pennsylvania-New Jersey-Maryland Interconnection (PJM) is the Mid-Atlantic electric grid case study that was used to examine if a flex reserve market can be utilized for integrating large capacities of wind generation in a lowcost manner for those providing, purchasing and dispatching these short-term balancing services. The following work consists of three studies. The first examines the ability of a hydroelectric facility to provide short-term forecast error balancing services via a flex reserve market, identifying the operational constraints that inhibit a multi-purpose dam facility to meet the desired flexible energy demand. The second study transitions from the hydroelectric facility as the decision maker providing flex reserve services to the wind plant as the decision maker purchasing these services. In this second study, methods for allocating the costs of flex reserve services under different wind policy scenarios are explored that aggregate farms into different groupings to identify the least-cost strategy for balancing the costs of hourly day-ahead forecast errors. The least-cost strategy may be different for an individual wind plant and for the system operator, noting that the least-cost strategy is highly sensitive to cost allocation and aggregation schemes. The latter may also cause cross-subsidies in the cost for balancing wind forecast errors among the different wind farms. The third study builds from the second, with the objective to quantify the amount of flex reserves needed for balancing future forecast errors using a probabilistic approach (quantile regression) to estimating future forecast errors. The results further examine the usefulness of separate flexible markets PJM could use for balancing oversupply and undersupply events, similar to the regulation up and down markets used in Europe. These three studies provide the following results and insights to large-scale wind integration using actual PJM wind farm data that describe the markets and generators within PJM. • Chapter 2 provides an in-depth analysis of the valuable, yet highly-constrained, energy services multi-purpose hydroelectric facilities can provide, though the opportunity cost for providing these services can result in large deviations from the reservoir policies with minimal revenue gain in comparison to dedicating the whole of dam capacity to providing day-ahead, baseload generation. • Chapter 3 quantifies the system-wide efficiency gains and the distributive effects of PJM's decision to act as a single balancing authority, which means that it procures ancillary services across its entire footprint simultaneously. This can be contrasted to Midwest Independent System Operator (MISO), which has several balancing authorities operating under its footprint. • Chapter 4 uses probabilistic methods to estimate the uncertainty in the forecast errors and the quantity of energy needed to balance these forecast errors at a certain percentile. Current practice is to use a point forecast that describes the conditional expectation of the dependent variable at each time step. The approach here uses quantile regression to describe the relationship between independent variable and the conditional quantiles (equivalently the percentiles) of the dependent variable. An estimate of the conditional density is performed, which contains information about the covariate relationship of the sign of the forecast errors (negative for too much wind generation and positive for too little wind generation) and the wind power forecast. This additional knowledge may be implemented in the decision process to more accurately schedule day-ahead wind generation bids and provide an example for using separate markets for balancing an oversupply and undersupply of generation. Such methods are currently used for coordinating large footprints of wind generation in Europe.

Variable speed generator technology options for wind turbine generators

NASA Technical Reports Server (NTRS)

Lipo, T. A.

1995-01-01

The electrical system options for variable speed operation of a wind turbine generator are treated in this paper. The key operating characteristics of each system are discussed and the major advantages and disadvantages of each are identified

Multi-time scale energy management of wind farms based on comprehensive evaluation technology

NASA Astrophysics Data System (ADS)

Xu, Y. P.; Huang, Y. H.; Liu, Z. J.; Wang, Y. F.; Li, Z. Y.; Guo, L.

2017-11-01

A novel energy management of wind farms is proposed in this paper. Firstly, a novel comprehensive evaluation system is proposed to quantify economic properties of each wind farm to make the energy management more economical and reasonable. Then, a combination of multi time-scale schedule method is proposed to develop a novel energy management. The day-ahead schedule optimizes unit commitment of thermal power generators. The intraday schedule is established to optimize power generation plan for all thermal power generating units, hydroelectric generating sets and wind power plants. At last, the power generation plan can be timely revised in the process of on-line schedule. The paper concludes with simulations conducted on a real provincial integrated energy system in northeast China. Simulation results have validated the proposed model and corresponding solving algorithms.

Multiple and variable speed electrical generator systems for large wind turbines

NASA Technical Reports Server (NTRS)

Andersen, T. S.; Hughes, P. S.; Kirschbaum, H. S.; Mutone, G. A.

1982-01-01

A cost effective method to achieve increased wind turbine generator energy conversion and other operational benefits through variable speed operation is presented. Earlier studies of multiple and variable speed generators in wind turbines were extended for evaluation in the context of a specific large sized conceptual design. System design and simulation have defined the costs and performance benefits which can be expected from both two speed and variable speed configurations.

Wind turbine having a direct-drive drivetrain

DOEpatents

Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.

2011-02-22

A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle via a bearing assembly. The wind rotor hub includes an opening having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity inside the wind rotor hub. The spindle is attached to a turret supported by a tower. Each of the spindle, turret and tower has an interior cavity that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.

Tail Shape Design of Boat Wind Turbines

NASA Astrophysics Data System (ADS)

Singamsitty, Venkatesh

Wind energy is a standout among the most generally utilized sustainable power source assets. A great deal of research and improvements have been happening in the wind energy field. Wind turbines are mechanical devices that convert kinetic energy into electrical power. Boat wind turbines are for the small-scale generation of electric power. In order to catch wind energy effectively, boat wind turbines need to face wind direction. Tails are used in boat wind turbines to alter the wind turbine direction and receive the variation of the incoming direction of wind. Tails are used to change the performance of boat wind turbines in an effective way. They are required to generate a quick and steady response as per change in wind direction. Tails can have various shapes, and their effects on boat wind turbines are different. However, the effects of tail shapes on the performance of boat wind turbines are not thoroughly studied yet. In this thesis, five tail shapes were studied. Their effects on boat wind turbines were investigated. The power extracted by the turbines from the air and the force acting on the boat wind turbine tail were analyzed. The results of this thesis provide a guideline of tail shape design for boat wind turbines.

Wind power as an electrical energy source in Illinois

NASA Astrophysics Data System (ADS)

Wendland, W. M.

1982-03-01

A preliminary estimate of the total wind power available in Illinois was made using available historical data, and projections of cost savings due to the presence of wind-generated electricity were attempted. Wind data at 10 m height were considered from nine different sites in the state, with three years data nominally being included. Wind-speed frequency histograms were developed for day and night periods, using a power law function to extrapolate the 10 m readings to 20 m. Wind speeds over the whole state were found to average over 8 mph, the cut-in point for most wind turbines, for from 40-63% of the time. A maximum of 75% run-time was determined for daylight hours in April-May. A reference 1.8 kW windpowered generator was used in annual demand projections for a reference one family home, using the frequency histograms. The small generator was projected to fulfill from 25-53% of the annual load, and, based on various cost assumptions, exhibited paybacks taking from 14-27 yr.

Mod-5A wind turbine generator program design report. Volume 4: Drawings and specifications, book 1

NASA Astrophysics Data System (ADS)

1984-08-01

The design, development and analysis of the 7.3 MW MOD-5A wind turbine generator is documented. Volume 4 contains the drawings and specifications that were developed in preparation for building the MOD-5A wind turbine generator. This is the first of five books of volume four. It contains structural design criteria, generator step-up transformer specs, specs for design, fabrication and testing of the system, specs for the ground control enclosure, systems specs, slip ring specs, and control system specs.

Mod-5A Wind Turbine Generator Program Design Report. Volume 4: Drawings and Specifications, Book 1

NASA Technical Reports Server (NTRS)

1984-01-01

The design, development and analysis of the 7.3 MW MOD-5A wind turbine generator is documented. Volume 4 contains the drawings and specifications that were developed in preparation for building the MOD-5A wind turbine generator. This is the first of five books of volume four. It contains structural design criteria, generator step-up transformer specs, specs for design, fabrication and testing of the system, specs for the ground control enclosure, systems specs, slip ring specs, and control system specs.

A HPC “Cyber Wind Facility” Incorporating Fully-Coupled CFD/CSD for Turbine-Platform-Wake Interactions with the Atmosphere and Ocean

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brasseur, James G.

The central aims of the DOE-supported “Cyber Wind Facility” project center on the recognition that wind turbines over land and ocean generate power from atmospheric winds that are inherently turbulent and strongly varying, both spatially over the rotor disk and in temporally as the rotating blades pass through atmospheric eddies embedded within the mean wind. The daytime unstable atmospheric boundary layer (ABL) is particularly variable in space time as solar heating generates buoyancy-driven motions that interact with strong mean shear in the ABL “surface layer,” the lowest 200 - 300 m where wind turbines reside in farms. With the “Cybermore » Wind Facility” (CWF) program we initiate a research and technology direction in which “cyber data” are generated from “computational experiments” within a “facility” akin to a wind tunnel, but with true space-time atmospheric turbulence that drive utility-scale wind turbines at full-scale Reynolds numbers. With DOE support we generated the key “modules” within a computational framework to create a first generation Cyber Wind Facility (CWF) for single wind turbines in the daytime ABL---both over land where the ABL globally unstable and over water with closer-to-neutral atmospheric conditions but with time response strongly affected by wave-induced forcing of the wind turbine platform (here a buoy configuration). The CWF program has significantly improved the accuracy of actuator line models, evaluated with the Cyber Wind Facility in full blade-boundary-layer-resolved mode. The application of the CWF made in this program showed the existence of important ramp-like response events that likely contribute to bearing fatigue failure on the main shaft and that the advanced ALM method developed here captures the primary nonsteady response characteristics. Long-time analysis uncovered distinctive key dynamics that explain primary mechanisms that underlie potentially deleterious load transients. We also showed that blade bend-twist coupling plays a central role in the elastic responses of the blades to atmospheric turbulence, impacting turbine power.« less

Collected Papers on Wind Turbine Technology

NASA Technical Reports Server (NTRS)

Spera, David A. (Editor)

1995-01-01

R and D projects on electricity generating wind turbines were conducted at the NASA Lewis Research Center from 1973 to 1988. Most projects were sponsored by the U.S. Department of Energy (DOE), a major element of its Federal Wind Energy Program. Another large wind turbine project was by the Bureau of Reclamation of the U.S. Department of Interior (DOI). From 1988 to 1995, NASA wind energy activities have been directed toward the transfer of technology to commercial and academic organizations. As part of these technology transfer activities, previously unpublished manuscripts have been assembled and presented here to share the wind turbine research results with the wind energy community. A variety of wind turbine technology topics are discussed: Wind and wake models; Airfoil properties; Structural analysis and testing; Control systems; Variable speed generators; and acoustic noise. Experimental and theoretical results are discussed.

Controllable Grid Interface for Testing Ancillary Service Controls and Fault Performance of Utility-Scale Wind Power Generation: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gevorgian, Vahan; Koralewicz, Przemyslaw; Wallen, Robb

The rapid expansion of wind power has led many transmission system operators to demand modern wind power plants to comply with strict interconnection requirements. Such requirements involve various aspects of wind power plant operation, including fault ride-through and power quality performance as well as the provision of ancillary services to enhance grid reliability. During recent years, the National Renewable Energy Laboratory (NREL) of the U.S. Department of Energy has developed a new, groundbreaking testing apparatus and methodology to test and demonstrate many existing and future advanced controls for wind generation (and other renewable generation technologies) on the multimegawatt scale andmore » medium-voltage levels. This paper describes the capabilities and control features of NREL's 7-MVA power electronic grid simulator (also called a controllable grid interface, or CGI) that enables testing many active and reactive power control features of modern wind turbine generators -- including inertial response, primary and secondary frequency responses, and voltage regulation -- under a controlled, medium-voltage grid environment. In particular, this paper focuses on the specifics of testing the balanced and unbalanced fault ride-through characteristics of wind turbine generators under simulated strong and weak medium-voltage grid conditions. In addition, this paper provides insights on the power hardware-in-the-loop feature implemented in the CGI to emulate (in real time) the conditions that might exist in various types of electric power systems under normal operations and/or contingency scenarios. Using actual test examples and simulation results, this paper describes the value of CGI as an ultimate modeling validation tool for all types of 'grid-friendly' controls by wind generation.« less

Wind energy potential analysis in Al-Fattaih-Darnah

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tjahjana, Dominicus Danardono Dwi Prija, E-mail: danar1405@gmail.com; Salem, Abdelkarim Ali, E-mail: keemsalem@gmail.com; Himawanto, Dwi Aries, E-mail: dwiarieshimawanto@gmail.com

2016-03-29

In this paper the wind energy potential in Al-Fattaih-Darnah, Libya, had been studied. Wind energy is very attractive because it can provide a clean and renewable energy. Due mostly to the uncertainty caused by the chaotic characteristics of wind near the earth’s surface, wind energy characteristic need to be investigated carefully in order to get consistent power generation. This investigation was based on one year wind data measured in 2003. As a result of the analysis, wind speed profile and wind energy potential have been developed. The wind energy potential of the location is looked very promising to generate electricity.more » The annual wind speed of the site is 8.21 m/s and the wind speed carrying maximum energy is 7.97 m/s. The annual power density of the site is classified into class 3. The Polaris P50-500 wind turbine can produce 768.39 M Wh/year and has capacity factor of 17.54%.« less

Adequacy assessment of composite generation and transmission systems incorporating wind energy conversion systems

NASA Astrophysics Data System (ADS)

Gao, Yi

The development and utilization of wind energy for satisfying electrical demand has received considerable attention in recent years due to its tremendous environmental, social and economic benefits, together with public support and government incentives. Electric power generation from wind energy behaves quite differently from that of conventional sources. The fundamentally different operating characteristics of wind energy facilities therefore affect power system reliability in a different manner than those of conventional systems. The reliability impact of such a highly variable energy source is an important aspect that must be assessed when the wind power penetration is significant. The focus of the research described in this thesis is on the utilization of state sampling Monte Carlo simulation in wind integrated bulk electric system reliability analysis and the application of these concepts in system planning and decision making. Load forecast uncertainty is an important factor in long range planning and system development. This thesis describes two approximate approaches developed to reduce the number of steps in a load duration curve which includes load forecast uncertainty, and to provide reasonably accurate generating and bulk system reliability index predictions. The developed approaches are illustrated by application to two composite test systems. A method of generating correlated random numbers with uniform distributions and a specified correlation coefficient in the state sampling method is proposed and used to conduct adequacy assessment in generating systems and in bulk electric systems containing correlated wind farms in this thesis. The studies described show that it is possible to use the state sampling Monte Carlo simulation technique to quantitatively assess the reliability implications associated with adding wind power to a composite generation and transmission system including the effects of multiple correlated wind sites. This is an important development as it permits correlated wind farms to be incorporated in large practical system studies without requiring excessive increases in computer solution time. The procedures described in this thesis for creating monthly and seasonal wind farm models should prove useful in situations where time period models are required to incorporate scheduled maintenance of generation and transmission facilities. There is growing interest in combining deterministic considerations with probabilistic assessment in order to evaluate the quantitative system risk and conduct bulk power system planning. A relatively new approach that incorporates deterministic and probabilistic considerations in a single risk assessment framework has been designated as the joint deterministic-probabilistic approach. The research work described in this thesis illustrates that the joint deterministic-probabilistic approach can be effectively used to integrate wind power in bulk electric system planning. The studies described in this thesis show that the application of the joint deterministic-probabilistic method provides more stringent results for a system with wind power than the traditional deterministic N-1 method because the joint deterministic-probabilistic technique is driven by the deterministic N-1 criterion with an added probabilistic perspective which recognizes the power output characteristics of a wind turbine generator.

77 FR 42719 - Notice of Effectiveness of Exempt Wholesale Generator or Foreign Utility Company Status

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-20

... Docket Nos. Sherbino I Wind Farm LLC EG12-43-000 Eagle Point Power Generation LLC....... EG12-53-000... Mountain Solar 2, LLC EG12-59-000 Minok Wind, LLC EG12-60-000 Senate Wind, LLC EG12-61-000 Canadian Hills Wind, LLC EG12-62-000 Moore Solar, Inc FC12-6-000 Sombra Solar, Inc FC12-7-000 Take notice that during...

Methods and apparatus for twist bend coupled (TCB) wind turbine blades

DOEpatents

Moroz, Emilian Mieczyslaw; LeMieux, David Lawrence; Pierce, Kirk Gee

2006-10-10

A method for controlling a wind turbine having twist bend coupled rotor blades on a rotor mechanically coupled to a generator includes determining a speed of a rotor blade tip of the wind turbine, measuring a current twist distribution and current blade loading, and adjusting a torque of a generator to change the speed of the rotor blade tip to thereby increase an energy capture power coefficient of the wind turbine.

Wind turbines: is there a human health risk?

PubMed

Roberts, Jennifer D; Roberts, Mark A

2013-04-01

The term "Wind Turbine Syndrome" was coined in a recently self-published book, which hypothesized that a multitude of symptoms such as headache and dizziness resulted from wind turbines generating low frequency sound (LFS). The objective of this article is to provide a summary of the peer-reviewed literature on the research that has examined the relationship between human health effects and exposure to LFS and sound generated from the operation of wind turbines. At present, a specific health condition has not been documented in the peer-reviewed literature that has been classified as a disease caused by exposure to sound levels and frequencies generated by the operation of wind turbines. Communities are experiencing a heightened sense of annoyance and fear from the development and siting of wind turbine farms. High-quality research and effective risk communication can advance this course from one of panic to one of understanding and exemplification for other environmental advancements.

Hybrid renewable energy system using doubly-fed induction generator and multilevel inverter

NASA Astrophysics Data System (ADS)

Ahmed, Eshita

The proposed hybrid system generates AC power by combining solar and wind energy converted by a doubly-fed induction generator (DFIG). The DFIG, driven by a wind turbine, needs rotor excitation so the stator can supply a load or the grid. In a variable-speed wind energy system, the stator voltage and its frequency vary with wind speed, and in order to keep them constant, variable-voltage and variable-frequency rotor excitation is to be provided. A power conversion unit supplies the rotor, drawing power either from AC mains or from a PV panel depending on their availability. It consists of a multilevel inverter which gives lower harmonic distortion in the stator voltage. Maximum power point tracking techniques have been implemented for both wind and solar power. The complete hybrid renewable energy system is implemented in a PSIM-Simulink interface and the wind energy conversion portion is realized in hardware using dSPACE controller board.

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

NASA Astrophysics Data System (ADS)

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

2010-12-01

Wind energy decision makers are required to make critical judgments on a daily basis with regard to energy generation, distribution, demand, storage, and integration. Accurate knowledge of the present and future state of the atmosphere is vital in making these decisions. As wind energy portfolios expand, this forecast problem is taking on new urgency because wind forecast inaccuracies frequently lead to substantial economic losses and constrain the national expansion of renewable energy. Improved weather prediction and precise spatial analysis of small-scale weather events are crucial for renewable energy management. In early 2009, the National Center for Atmospheric Research (NCAR) began a collaborative project with Xcel Energy Services, Inc. to perform research and develop technologies to improve Xcel Energy's ability to increase the amount of wind energy in their generation portfolio. The agreement and scope of work was designed to provide highly detailed, localized wind energy forecasts to enable Xcel Energy to more efficiently integrate electricity generated from wind into the power grid. The wind prediction technologies are designed to help Xcel Energy operators make critical decisions about powering down traditional coal and natural gas-powered plants when sufficient wind energy is predicted. The wind prediction technologies have been designed to cover Xcel Energy wind resources spanning a region from Wisconsin to New Mexico. The goal of the project is not only to improve Xcel Energy’s wind energy prediction capabilities, but also to make technological advancements in wind and wind energy prediction, expand our knowledge of boundary layer meteorology, and share the results across the renewable energy industry. To generate wind energy forecasts, NCAR is incorporating observations of current atmospheric conditions from a variety of sources including satellites, aircraft, weather radars, ground-based weather stations, wind profilers, and even wind sensors on individual wind turbines. The information is utilized by several technologies including: a) the Weather Research and Forecasting (WRF) model, which generates finely detailed simulations of future atmospheric conditions, b) the Real-Time Four-Dimensional Data Assimilation System (RTFDDA), which performs continuous data assimilation providing the WRF model with continuous updates of the initial atmospheric state, 3) the Dynamic Integrated Forecast System (DICast®), which statistically optimizes the forecasts using all predictors, and 4) a suite of wind-to-power algorithms that convert wind speed to power for a wide range of wind farms with varying real-time data availability capabilities. In addition to these core wind energy prediction capabilities, NCAR implemented a high-resolution (10 km grid increment) 30-member ensemble RTFDDA prediction system that provides information on the expected range of wind power over a 72-hour forecast period covering Xcel Energy’s service areas. This talk will include descriptions of these capabilities and report on several topics including initial results of next-day forecasts and nowcasts of wind energy ramp events, influence of local observations on forecast skill, and overall lessons learned to date.

NREL Offshore Balance-of-System Model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maness, Michael; Maples, Benjamin; Smith, Aaron

The U.S. Department of Energy (DOE) has investigated the potential for 20% of nationwide electricity demand to be generated from wind by 2030 and, more recently, 35% by 2050. Achieving this level of wind power generation may require the development and deployment of offshore wind technologies. DOE (2008) has indicated that reaching these 2030 and 2050 scenarios could result in approximately 10% and 20%, respectively, of wind energy generation to come from offshore resources. By the end of 2013, 6.5 gigawatts of offshore wind were installed globally. The first U.S. project, the Block Island Wind Farm off the coast ofmore » Rhode Island, has recently begun operations. One of the major reasons that offshore wind development in the United States is lagging behind global trends is the high capital expenditures required. An understanding of the costs and associated drivers of building a commercial-scale offshore wind plant in the United States will inform future research and help U.S. investors feel more confident in offshore wind development. In an effort to explain these costs, the National Renewable Energy Laboratory has developed the Offshore Balance-of-System model.« less

Wind and turbine characteristics needed for integration of wind turbine arrays into a utility system

NASA Technical Reports Server (NTRS)

Park, G. L.

1982-01-01

Wind data and wind turbine generator (WTG) performance characteristics are often available in a form inconvenient for use by utility planners and engineers. The steps used by utility planners are summarized and the type of wind and WTG data needed for integration of WTG arrays suggested. These included long term yearly velocity averages for preliminary site feasibility, hourly velocities on a 'wind season' basis for more detailed economic analysis and for reliability studies, worst-case velocity profiles for gusts, and various minute-to-hourly velocity profiles for estimating the effect of longer-term wind fluctuations on utility operations. wind turbine data needed includes electrical properties of the generator, startup and shutdown characteristics, protection characteristics, pitch control response and control strategy, and electro-mechanical model for stability analysis.

Project demonstration of wind-turbine electricity: Interconnecting a northern Michigan fruit farm with a major utility

NASA Astrophysics Data System (ADS)

Amon, D. M.

Progress is reviewed in a project to test the economic feasibility of wind turbine technology for generating electricity. The use of wind generating electricity on a commercial fruit farm interconnecting a commercial fruit farm with a major utility to sell power are the find project goals.

75 FR 80484 - Combined Notice of Filings #1

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-22

... exempt wholesale generator status re Hatchet Ridge Wind 2010-B. Filed Date: 12/14/2010. Accession Number... of exempt wholesale generator status re Hatchet Ridge Wind 2010-A. Filed Date: 12/14/2010. Accession... Mountain Wind Farm LGIA to be effective 11/24/ 2010. Filed Date: 12/14/2010. Accession Number: 20101214...

78 FR 73239 - Small Generator Interconnection Agreements and Procedures

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-05

... distributed resources.\\35\\ Public Interest Organizations go on to state that: \\29\\ See, e.g., American Wind... Society and Wind on the Wires are referred to collectively as Public Interest Organizations in this Final...\\ Similarly, installed wind generation with a capacity of 20 MW or less has increased in the contiguous United...

75 FR 74040 - Intent To Prepare an Environmental Impact Statement and To Conduct Scoping Meetings...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-30

... Proposed Project NextEra's proposed Project would consist of up to 100 wind turbine generators with a... roads. NextEra has secured leases with willing landowners for its wind generation turbines and related... substantial natural resources conflicts. NextEra's siting process for the wind turbine strings and associated...