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21-kW Thin-Film PV Technology Validation -- An NREL/Solar Energy Centre of India MOU Cooperative Project
This paper summarizes findings during a one-week (27-31 October 2003) site visit to the Thin-Film Technology Test Bed at India's Solar Energy Centre (SEC) near New Delhi. The U.S. and Indian governments signed a Memorandum of Understanding in March 2000 to undertake a 50-50 cost-shared 21-kW thin-film PV technology validation project to evaluate the performance of thin-film photovoltaic (PV) modules under Indian climatic conditions. This project benefits Indian researchers by giving them experience with cost-effective PV materials, and it benefits the United States because data will be sent to the appropriate U.S. thin-film PV manufacturers for evaluation and analysis. During the visit, NREL personnel engaged in technical discussions regarding thin-film PV technologies with Ministry of Non-Conventional Energy Sources engineers and scientists. Issues included inspecting the newly constructed arrays, discussing better methods of electrically loading the PV arrays, taking I-V traces, and gathering baseline I-V data.
Date:
January 1, 2005
Creator:
McNutt, P. F. & Ullal, H. S.
Object Type:
Article
System:
The UNT Digital Library
915-MHz Radar Wind Profiler (915RWP) Handbook
The 915 MHz radar wind profiler/radio acoustic sounding system (RWP/RASS) measures wind profiles and backscattered signal strength between (nominally) 0.1 km and 5 km and virtual temperature profiles between 0.1 km and 2.5 km. It operates by transmitting electromagnetic energy into the atmosphere and measuring the strength and frequency of backscattered energy. Virtual temperatures are recovered by transmitting an acoustic signal vertically and measuring the electromagnetic energy scattered from the acoustic wavefront. Because the propagation speed of the acoustic wave is proportional to the square root of the virtual temperature of the air, the virtual temperature can be recovered by measuring the Doppler shift of the scattered electromagnetic wave.
Date:
January 1, 2005
Creator:
Coulter, R.
Object Type:
Report
System:
The UNT Digital Library
2004 Annual Summary Report for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site, Nye County, Nevada
The Maintenance Plan for the Performance Assessments and Composite Analyses for the Area 3 and Area 5 Radioactive Waste Management Sites at the Nevada Test Site (Bechtel Nevada, 2000) requires an annual review to assess the adequacy of the performance assessments (PAs) and composite analyses (CAs) for each of the facilities, and reports the results in an annual summary report to the U.S. Department of Energy Headquarters. The Disposal Authorization Statements for the Area 3 and Area 5 Radioactive Waste Management Sites (RWMSs) also require that such reviews be made and that secondary or minor unresolved issues be tracked and addressed as part of the maintenance plan (U.S. Department of Energy [DOE]). The U.S. Department of Energy National Nuclear Security Administration Nevada Site Office performed annual reviews in fiscal year (FY) 2004 by evaluating operational factors and research results that impact the continuing validity of the PA and CA results. This annual summary report presents data and conclusions from the FY 2004 review, and determines the adequacy of the PAs and CAs. Operational factors, such as the waste form and containers, facility design, waste receipts, closure plans, as well as monitoring results and research and development (R&D) activities were reviewed …
Date:
January 1, 2005
Creator:
Yucel, Vefa
Object Type:
Report
System:
The UNT Digital Library
3D Magnetotelluric characterization of the COSO GeothermalField
Knowledge of the subsurface electrical resistivity/conductivity can contribute to a better understanding of complex hydrothermal systems, typified by Coso geothermal field, through mapping the geometry (bounds and controlling structures) over existing production. Three-dimensional magnetotelluric (MT) inversion is now an emerging technology for characterizing the resistivity structures of complex geothermal systems. The method appears to hold great promise, but histories exploiting truly 3D inversion that demonstrate the advantages that can be gained by acquiring and analyzing MT data in three dimensions are still few in number. This project will address said issue, by applying 3D MT forward modeling and inversion to a MT data set acquired over the Coso geothermal field. The goal of the project is to provide the capability to image large geothermal reservoirs in a single self-consistent model. Initial analysis of the Coso MT data has been carried out using 2D MT imaging technology to construct an initial 3D resistivity model from a series of 2D resistivity images obtained using the inline electric field measurements (Zxy impedance elements) along different measurement transects. This model will be subsequently refined through a 3D inversion process. The initial 3D resistivity model clearly shows the controlling geological structures possibly influencing well production …
Date:
January 1, 2005
Creator:
Newman, Gregory A.; Hoversten, Michael; Gasperikova, Erika & Wannamaker, Philip E.
Object Type:
Article
System:
The UNT Digital Library
Abundance of green tree frogs and insects in artificial canopy gaps in a bottomland hardwood forest.
Horn, Scott, James L. Hanula, Michael D. Ulyshen, and John C. Kilgo. 2005. Abundance of green tree frogs and insects in artificial canopy gaps in a bottomland hardwood forest. Am. Midl. Nat. 153:321-326. Abstract: We found more green tree frogs (Hyla cinerea) in canopy gaps than in closed canopy forest. Of the 331 green tree frogs observed, 88% were in canopy gaps. Likewise, higher numbers and biomasses of insects were captured in the open gap habitat. Flies were the most commonly collected insect group accounting for 54% of the total capture. These data suggest that one reason green tree frogs were more abundant in canopy gaps was the increased availability of prey and that small canopy gaps provide early successional habitats that are beneficial to green tree frog populations.
Date:
January 1, 2005
Creator:
Horn, Scott; Hanula, James L.; Ulyshen, Michael D. & Kilgo, John C.
Object Type:
Article
System:
The UNT Digital Library
Adaptive Management and Planning Models for Cultural Resources in Oil & Gas Fields in New Mexico and Wyoming, Semi-Annual Progress Report: July 1 - December 31, 2004
This report summarizes activities that have taken place in the last 6 months (July 2004-December 2004) under the DOE-NETL cooperative agreement ''Adaptive Management and Planning Models for Cultural Resources in Oil and Gas Fields, New Mexico and Wyoming'' DE-FC26-02NT15445. This project examines the practices and results of cultural resource investigation and management in two different oil and gas producing areas of the US: southeastern New Mexico and the Powder River Basin of Wyoming. The project evaluates how cultural resource investigations have been conducted in the past and considers how investigation and management could be pursued differently in the future. The study relies upon full database population for cultural resource inventories and resources and geomorphological studies. These are the basis for analysis of cultural resource occurrence, strategies for finding and evaluating cultural resources, and recommendations for future management practices. Activities can be summarized as occurring in either Wyoming or New Mexico.
Date:
January 1, 2005
Creator:
Robinson, Peggy
Object Type:
Report
System:
The UNT Digital Library
Advanced Heat Transfer and Thermal Storage Fluids
The design of the next generation solar parabolic trough systems for power production will require the development of new thermal energy storage options with improved economics or operational characteristics. Current heat-transfer fluids such as VP-1?, which consists of a eutectic mixture of biphenyl and diphenyl oxide, allow a maximum operating temperature of ca. 300 C, a limit above which the vapor pressure would become too high and would require pressure-rated tanks. The use of VP-1? also suffers from a freezing point around 13 C that requires heating during cold periods. One of the goals for future trough systems is the use of heat-transfer fluids that can act as thermal storage media and that allow operating temperatures around 425 C combined with lower limits around 0 C. This paper presents an outline of our latest approach toward the development of such thermal storage fluids.
Date:
January 1, 2005
Creator:
Moens, L. & Blake, D.
Object Type:
Article
System:
The UNT Digital Library
Advanced Indoor Module Light-Soaking Facility
An overview of the accelerated, indoor light-soaking test station is presented in this paper, along with data obtained for six modules that underwent exposure. The station comprises a climate-controlled chamber equipped with a solar simulator that allows 1-sun light intensity exposure. Concurrently, we monitor the electrical characteristics of multiple PV modules and exercise active control over their electrical bias using programmable electronic loads, interfaced to a data acquisition system that acquires power-tracking and current-voltage data. This capability allows us to the test different bias conditions and to cyclically alternate between them. Additionally, we can vary the light intensity and module temperatures to garner realistic temperature coefficients of module performance. Data obtained on cadmium telluride (CdTe) and amorphous silicon (a-Si) modules are presented.
Date:
January 1, 2005
Creator:
del Cueto, J. A.; Osterwald, C. & Pruett, J.
Object Type:
Article
System:
The UNT Digital Library
Advanced polychromator systems for remote chemical sensing (LDRD project 52575).
The objective of this LDRD project was to develop a programmable diffraction grating fabricated in SUMMiT V{trademark}. Two types of grating elements (vertical and rotational) were designed and demonstrated. The vertical grating element utilized compound leveraged bending and the rotational grating element used vertical comb drive actuation. This work resulted in two technical advances and one patent application. Also a new optical configuration of the Polychromator was demonstrated. The new optical configuration improved the optical efficiency of the system without degrading any other aspect of the system. The new configuration also relaxes some constraint on the programmable diffraction grating.
Date:
January 1, 2005
Creator:
Sinclair, Michael B.; Pfeifer, Kent Bryant & Allen, James Joe
Object Type:
Report
System:
The UNT Digital Library
Advances in Solar Radiometry and Metrology
The Solar Radiometry and Metrology task at the National Renewable Energy Laboratory (NREL) provides traceable optical radiometric calibrations and measurements to photovoltaic (PV) researchers and the PV industry. Traceability of NREL solar radiometer calibrations to the World Radiometric Reference (WRR) was accomplished during the NREL Pyrheliometer Comparison in October 2003. The task has calibrated 10 spectral and more than 180 broadband radiometers for solar measurements. Other accomplishments include characterization of pyranometer thermal offset errors with laboratory and spectral modeling tools; developing a simple scheme to correct pyranometer data for known responsivity variations; and measuring detailed spectral distributions of the NREL High Intensity Pulsed Solar Simulator (HIPSS) as a function of lamp voltage and time. The optical metrology functions support the NREL Measurement and Characterization Task effort for ISO 17025 accreditation of NREL Solar Reference Cell Calibrations. Optical metrology functions have been integrated into the NREL quality system and audited for ISO17025 compliance.
Date:
January 1, 2005
Creator:
Myers, D.; Andreas, A.; Reda, I.; Gotseff, P.; Wilcox, S.; Stoffel, T. et al.
Object Type:
Article
System:
The UNT Digital Library
Advances in the In-House CdTe Research Activities at NREL
NREL in-house CdTe research activities have impacted a broad range of recent program priorities. Studies aimed at industrially relevant applications have produced new materials and processes that enhance the performance of devices based on commercial materials (e.g., soda-lime glass, SnO2:F). Preliminary tests of the effectiveness of these novel components using large-scale processes have been encouraging. Similarly, electro- and nano-probe techniques have been developed and used to study the evolution and function of CdTe grain boundaries. Finally, cathodoluminescence (CL) and photoluminescence (PL) studies on single-crystal samples have yielded improved understanding of how various processes may combine to produce important defects in CdTe films.
Date:
January 1, 2005
Creator:
Gessert, T.; Wu, X.; Dhere, R.; Moutinho, H.; Smith, S.; Romero, M. et al.
Object Type:
Article
System:
The UNT Digital Library
AeroDyn Theory Manual
AeroDyn is a set of routines used in conjunction with an aeroelastic simulation code to predict the aerodynamics of horizontal axis wind turbines. These subroutines provide several different models whose theoretical bases are described in this manual. AeroDyn contains two models for calculating the effect of wind turbine wakes: the blade element momentum theory and the generalized dynamic-wake theory. Blade element momentum theory is the classical standard used by many wind turbine designers and generalized dynamic wake theory is a more recent model useful for modeling skewed and unsteady wake dynamics. When using the blade element momentum theory, various corrections are available for the user, such as incorporating the aerodynamic effects of tip losses, hub losses, and skewed wakes. With the generalized dynamic wake, all of these effects are automatically included. Both of these methods are used to calculate the axial induced velocities from the wake in the rotor plane. The user also has the option of calculating the rotational induced velocity. In addition, AeroDyn contains an important model for dynamic stall based on the semi-empirical Beddoes-Leishman model. This model is particularly important for yawed wind turbines. Another aerodynamic model in AeroDyn is a tower shadow model based on potential …
Date:
January 1, 2005
Creator:
Moriarty, P. J. & Hansen, A. C.
Object Type:
Report
System:
The UNT Digital Library
ALEGRA-MHD : version 4.6
ALEGRA is an arbitrary Lagrangian-Eulerian finite element code that emphasizes large distortion and shock propagation in inviscid fluids and solids. This document describes user options for modeling resistive magnetohydrodynamic, thermal conduction, and radiation emission effects.
Date:
January 1, 2005
Creator:
Garasi, Christopher Joseph; Cochrane, Kyle Robert; Mehlhorn, Thomas Alan; Haill, Thomas A.; Summers, Randall M. & Robinson, Allen Conrad
Object Type:
Report
System:
The UNT Digital Library
ALEGRA : version 4.6.
ALEGRA is an arbitrary Lagrangian-Eulerian multi-material finite element code used for modeling solid dynamics problems involving large distortion and shock propagation. This document describes the basic user input language and instructions for using the software.
Date:
January 1, 2005
Creator:
Wong, Michael K. W.; Summers, Randall M.; Petney, Sharon V.; Luchini, Christopher Bernard; Drake, Richard Roy; Carroll, Susan K. et al.
Object Type:
Report
System:
The UNT Digital Library
Amplitude Analysis of the Decay $D_s^+ \to \pi^+ \pi^- \pi^+$ in the Experiment E831/FOCUS
We present in this thesis the Dalitz Plot analysis of the D{sub s}{sup +} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup +} decay, with the data of the E831/FOCUS, that took data in 1996 and 1997. The masses and widhts of f{sub 0}(980) and f{sub 0}(1370) are free parametres of the fit on Dalitz Plot, objectiving to study in detail these resonances. After this analysis we present the Spectator Model study on the S wave in this decay. For this study we used the formalism developed by M. Svec [2] for scattering. We present the comparison between the Isobar Model, frequently used in Dalitz Plot analysis, and this formalism.
Date:
January 1, 2005
Creator:
Schilithz, Anderson Correa
Object Type:
Report
System:
The UNT Digital Library
Analysis of Devonian Black Shales in Kentucky for Potential Carbon Dioxide Sequestration and Enhanced Natural Gas Production Quarterly Report: July-Septmeber 2004
Devonian gas shales underlie approximately two-thirds of Kentucky. In the shale, natural gas is adsorbed on clay and kerogen surfaces. This is analogous to methane storage in coal beds, where CO{sub 2} is preferentially adsorbed, displacing methane. Black shales may similarly desorb methane in the presence of CO{sub 2}. Drill cuttings from the Kentucky Geological Survey Well Sample and Core Library were sampled to determine CO{sub 2} and CH{sub 4} adsorption isotherms. Sidewall core samples were acquired to investigate CO{sub 2} displacement of methane. An elemental capture spectroscopy log was acquired to investigate possible correlations between adsorption capacity and mineralogy. Average random vitrinite reflectance data range from 0.78 to 1.59 (upper oil to wet gas and condensate hydrocarbon maturity range). Total organic content determined from acid-washed samples ranges from 0.69 to 14 percent. CO{sub 2} adsorption capacities at 400 psi range from a low of 14 scf/ton in less organic-rich zones to more than 136 scf/ton. Initial estimates based on these data indicate a sequestration capacity of 5.3 billion tons of CO{sub 2} in the Lower Huron Member of the Ohio Shale of eastern Kentucky and as much as 28 billion tons total in the deeper and thicker parts of …
Date:
January 1, 2005
Creator:
Nuttall, Brandon C.
Object Type:
Report
System:
The UNT Digital Library
Analysis of eddy current distributions in the CMS magnet yoke during the solenoid discharge
Flux loops have been installed on selected segments of the magnetic flux return yoke of the 4 T superconducting coil of the Compact Muon Solenoid (CMS) detector under construction at CERN. Voltages induced in the loops during discharge of the solenoid will be sampled on-line during the entire discharge and integrated off-line to provide a measurement of the initial magnetic flux density in steel at the maximum field to an accuracy of a few percent. Although the discharge of the solenoid is rather slow (190 s time constant), the influence of eddy currents induced in the yoke elements should be estimated. The calculation of eddy currents is performed with Vector Fields program ELEKTRA. The results of calculations are reported.
Date:
January 1, 2005
Creator:
Klyukhin, V. I.; Campi, D.; Cure, B.; Gaddi, A.; Gerwig, H.; Grillet, J. P. et al.
Object Type:
Article
System:
The UNT Digital Library
Analysis of the habitat of Henslow's sparrows and Grasshopper sparrows compared to random grassland areas
Henslow's Sparrows are endangered prairie birds, and Grasshopper Sparrows are considered rare prairie birds. Both of these birds were abundant in Illinois, but their populations have been declining due to loss of the grasslands. This begins an ongoing study of the birds habitat so Fermilab can develop a land management plan for the Henslow's and Grasshoppers. The Henslow's were found at ten sites and Grasshoppers at eight sites. Once the birds were located, the vegetation at their sites was studied. Measurements of the maximum plant height, average plant height, and duff height were taken and estimates of the percent of grass, forbs, duff, and bare ground were recorded for each square meter studied. The same measurements were taken at ten random grassland sites on Fermilab property. Several t-tests were performed on the data, and it was found that both Henslow's Sparrows and Grasshopper Sparrows preferred areas with a larger percentage of grass than random areas. Henslow's also preferred areas with less bare ground than random areas, while Grasshoppers preferred areas with more bare ground than random areas. In addition, Grasshopper Sparrows preferred a lower percentage of forbs than was found in random areas and a shorter average plant height than …
Date:
January 1, 2005
Creator:
Maier, Kristen; Walton, Rod & Kasper, Peter
Object Type:
Article
System:
The UNT Digital Library
Analytical Methodologies for Detection of Gamma-Valerolactone, Delta-Valerolactone, Acephate and Azinphos Methyl and Their Associated Metabolites in Complex Biological Matrices
Non-invasive biomonitoring for chemicals of interest in law enforcement and similar monitoring of pesticides, together with their metabolites, can not only save money but can lead to faster medical attention for individuals exposed to these chemicals. This study describes methods developed for the analysis of gamma-valerolactone (GVL), delta-valerolactone (DVL), acephate, and azinphos methyl in saliva and serum. Liquid chromatography/mass spectrometry (LC/MS) operated in the negative and positive ion mode and gas chromatography/mass spectrometry (GC/MS) were used to analyze GVL and DVL. Although both analytical techniques worked well, lower detection limits were obtained with GC/MS. The lactones and their corresponding sodium salts were spiked into both saliva and serum. The lactones were isolated from saliva or serum using newly developed extraction techniques and then subsequently analyzed using GC/MS. The sodium salts of the lactones are nonvolatile and require derivatization prior to analysis by this method. N-methyl-N-(t-butyldimethylsilyl)-trifluoroacetamide (MTBSTFA) was ultimately selected as the reagent for derivatization because the acidic conditions required for reactions with diazomethane caused the salts to undergo intramolecular cyclization to the corresponding lactones. In vitro studies were conducted using rat liver microsomes to determine other metabolites associated with these compounds. Azinphos methyl and acephate are classified as organophosphate pesticides, …
Date:
January 1, 2005
Creator:
Zink, Erica; Clark, Ryan; Grant, Karen; Campbell, James & Hoppe, Erik
Object Type:
Article
System:
The UNT Digital Library
Application of Combinatorial Tools for Solar Cell Improvement -- New High Performance Transparent Conducting Oxides
Transparent conducting oxides (TCOs) can serve a variety of important functions in thin film photovoltaics such as transparent electrical contacts, antireflection coatings and chemical barriers. Two areas of particular interest are TCOs that can be deposited at low temperatures and TCOs with high carrier mobilities. We have employed combinatorial high-throughput approaches to investigate both these areas. Conductivities of s = 2500 W-1-cm-1 have been obtained for In-Zn-O (IZO) films deposited at 100 C and s > 5000 W-1-cm-1 for In-Ti-O (ITiO) and In-Mo-O (IMO) films deposited at 550 C. The highest mobility obtained was 83 cm2/V-sec for ITiO deposited at 550 C.
Date:
January 1, 2005
Creator:
Perkins, J.; Taylor, M.; van Hest, M.; Teplin, C.; Alleman, J.; Dabney, M. et al.
Object Type:
Article
System:
The UNT Digital Library
Application of deuteron-deuteron (d-d) fusion neutrons to 40ar/39/ar geochronology
This report talks about Application of deuteron-deuteron (d-d) fusion neutrons to 40ar/39/ar geochronology
Date:
January 1, 2005
Creator:
Renne, P.; Knight, K. B.; Nomade, S.; Leung, K. N. & Lou, T. P.
Object Type:
Article
System:
The UNT Digital Library
Application of independent component analysis to Fermilab Booster
Autocorrelation is applied to analyze sets of finite-sampling data such as the turn-by-turn beam position monitor (BPM) data in an accelerator. This method of data analysis, called the independent component analysis (ICA), is shown to be a powerful beam diagnosis tool for being able to decompose sampled signals into its underlying source signals. They find that the ICA has an advantage over the principle component analysis (PCA) used in the model-independent analysis (MIA) in isolating independent modes. The tolerance of the ICA method to noise in the BPM system is systematically studied. The ICA is applied to analyze the complicated beam motion in a rapid-cycling booster synchrotron at the Fermilab. Difficulties and limitations of the ICA method are also discussed.
Date:
January 1, 2005
Creator:
Huang, X. B.; Lee, S. Y.; Prebys, E. & Tomlin, R.
Object Type:
Article
System:
The UNT Digital Library
Applications of mineral carbonation to geological sequestration of CO2
Geological sequestration of CO2 is a promising near-term sequestration methodology. However, migration of the CO2 beyond the natural reservoir seals could become problematic, thus the identification of means to enhance the natural seals could prove beneficial. Injection of a mineral reactant slurry could provide a means to enhance the natural reservoir seals by supplying the necessary cations for precipitation of mineral carbonates. The subject study evaluates the merit of several mineral slurry injection strategies by conduct of a series of laboratory-scale CO2 flood tests on whole core samples of the Mt. Simon sandstone from the Illinois Basin.
Date:
January 1, 2005
Creator:
O'Connor, William K. & Rush, G.E.
Object Type:
Article
System:
The UNT Digital Library
Arsenic Sulfide Nanowire Formation on Fused Quartz Surfaces
Arsenic sulfide (AsxSy) nanowires were synthesized by an evaporation-condensation process in evacuated fused quartz ampoules. During the deposition process, a thin, colored film of AsxSy was deposited along the upper, cooler portion of the ampoule. The ampoule was sectioned and the deposited film analyzed using scanning electron microscopy (SEM) to characterize and semi-quantitatively evaluate the microstructural features of the deposited film. A variety of microstructures were observed that ranged from a continuous thin film (warmer portion of the ampoule), to isolated micron- and nano-scale droplets (in the intermediate portion), as well as nanowires (colder portion of the ampoule). Experiments were conducted to evaluate the effects of ampoule cleaning methods (e.g. modify surface chemistry) and quantity of source material on nanowire formation. The evolution of these microstructures in the thin film was determined to be a function of initial pressure, substrate temperature, substrate surface treatment, and initial volume of As2S3 glass. In a set of two experiments where the initial pressure, substrate thermal gradient, and surface treatment were the same, the initial quantity of As2S3 glass per internal ampoule volume was doubled from one test to the other. The results showed that AsxSy nanowires were only formed in the test with …
Date:
January 1, 2005
Creator:
Olmstead, J.; Riley, B. J.; Johnson, B. R. & Sundaram, S. K.
Object Type:
Article
System:
The UNT Digital Library