Net Metering and Interconnection Procedures-- Incorporating Best Practices (open access)

Net Metering and Interconnection Procedures-- Incorporating Best Practices

State utility commissions and utilities themselves are actively developing and revising their procedures for the interconnection and net metering of distributed generation. However, the procedures most often used by regulators and utilities as models have not been updated in the past three years, in which time most of the distributed solar facilities in the United States have been installed. In that period, the Interstate Renewable Energy Council (IREC) has been a participant in more than thirty state utility commission rulemakings regarding interconnection and net metering of distributed generation. With the knowledge gained from this experience, IREC has updated its model procedures to incorporate current best practices. This paper presents the most significant changes made to IREC’s model interconnection and net metering procedures.
Date: April 1, 2009
Creator: Jason Keyes, Kevin Fox, Joseph Wiedman, Staff at North Carolina Solar Center
Object Type: Article
System: The UNT Digital Library
Assessment of Contribution of Contemporary Carbon Sources to Size-Fractionated Particulate Matter and Time-Resolved Bulk Particulate Matter Using the Measurement of Radiocarbon (open access)

Assessment of Contribution of Contemporary Carbon Sources to Size-Fractionated Particulate Matter and Time-Resolved Bulk Particulate Matter Using the Measurement of Radiocarbon

This study was motivated by a desire to improve understanding of the sources contributing to the carbon that is an important component of airborne particulate matter (PM). The ultimate goal of this project was to lay a ground work for future tools that might be easily implemented with archived or routinely collected samples. A key feature of this study was application of radiocarbon measurement that can be interpreted to indicate the relative contributions from fossil and non-fossil carbon sources of atmospheric PM. Size-resolved PM and time-resolved PM{sub 10} collected from a site in Sacramento, CA in November 2007 (Phase I) and March 2008 (Phase II) were analyzed for radiocarbon and source markers such as levoglucosan, cholesterol, and elemental carbon. Radiocarbon data indicates that the contributions of non-fossil carbon sources were much greater than that from fossil carbon sources in all samples. Radiocarbon and source marker measurements confirm that a greater contribution of non-fossil carbon sources in Phase I samples was highly likely due to residential wood combustion. The present study proves that measurement of radiocarbon and source markers can be readily applied to archived or routinely collected samples for better characterization of PM sources. More accurate source apportionment will support …
Date: April 16, 2009
Creator: Hwang, H. M.; Young, T. M. & Buchholz, B. A.
Object Type: Report
System: The UNT Digital Library
Implementation Plans for a Systems Microbiology and Extremophile Research Facility (open access)

Implementation Plans for a Systems Microbiology and Extremophile Research Facility

Introduction Biological organisms long ago solved many problems for which scientists and engineers seek solutions. Microbes in particular offer an astonishingly diverse set of capabilities that can help revolutionize our approach to solving many important DOE problems. For example, photosynthetic organisms can generate hydrogen from light while simultaneously sequestering carbon. Others can produce enzymes that break down cellulose and other biomass to produce liquid fuels. Microbes in water and soil can capture carbon and store it in the earth and ocean depths. Understanding the dynamic interaction between living organisms and the environment is critical to predicting and mitigating the impacts of energy-production-related activities on the environment and human health. Collectively, microorganisms contain most of the biochemical diversity on Earth and they comprise nearly one-half of its biomass. They primary impact the planet by acting as catalysts of biogeochemical cycles; they capture light energy and fix CO2 in the worlds oceans, they degrade plant polymers and convert them to humus in soils, they weather rocks and facilitate mineral precipitation. Although the ability of selected microorganisms to participate in these processes is known, they rarely live in monoculture but rather function within communities. In spite of this, little is known about the …
Date: April 20, 2009
Creator: Wiley, H. S.
Object Type: Report
System: The UNT Digital Library
California Wintertime Precipitation in Regional and Global Climate Models (open access)

California Wintertime Precipitation in Regional and Global Climate Models

In this paper, wintertime precipitation from a variety of observational datasets, regional climate models (RCMs), and general circulation models (GCMs) is averaged over the state of California (CA) and compared. Several averaging methodologies are considered and all are found to give similar values when model grid spacing is less than 3{sup o}. This suggests that CA is a reasonable size for regional intercomparisons using modern GCMs. Results show that reanalysis-forced RCMs tend to significantly overpredict CA precipitation. This appears to be due mainly to overprediction of extreme events; RCM precipitation frequency is generally underpredicted. Overprediction is also reflected in wintertime precipitation variability, which tends to be too high for RCMs on both daily and interannual scales. Wintertime precipitation in most (but not all) GCMs is underestimated. This is in contrast to previous studies based on global blended gauge/satellite observations which are shown here to underestimate precipitation relative to higher-resolution gauge-only datasets. Several GCMs provide reasonable daily precipitation distributions, a trait which doesn't seem tied to model resolution. GCM daily and interannual variability is generally underpredicted.
Date: April 27, 2009
Creator: Caldwell, P M
Object Type: Article
System: The UNT Digital Library
Energy dependence of transverse momentum fluctuations in Pb+Pb collisions at the CERN Super Proton Synchrotron (SPS) at 20A to 158A GeV (open access)

Energy dependence of transverse momentum fluctuations in Pb+Pb collisions at the CERN Super Proton Synchrotron (SPS) at 20A to 158A GeV

Results are presented on event-by-event fluctuations of transverse momenta p{sub T} in central Pb+Pb interactions at 20A, 30A, 40A, 80A, and 158A GeV. The analysis was performed for charged particles at forward center-of-mass rapidity (1.1 < y*{sub {pi}} < 2.6). Three fluctuation measures were studied: the distribution of average transverse momentum M(p{sub T}) in the event, the {phi}{sub p{sub T}} fluctuation measure, and two-particle transverse momentum correlations. Fluctuations of p{sub T} are small and show no significant energy dependence in the energy range of the CERN Super Proton Synchrotron. Results are compared with QCD-inspired predictions for the critical point, and with the UrQMD model. Transverse momentum fluctuations, similar to multiplicity fluctuations, do not show the increase expected for freeze-out near the critical point of QCD.
Date: April 15, 2009
Creator: Collaboration, NA49 & Anticic, T.
Object Type: Article
System: The UNT Digital Library
Workforce Development: A Survey of Industry Needs and Training Approaches (open access)

Workforce Development: A Survey of Industry Needs and Training Approaches

This paper presents information and data collected during 2008 on PV workforce needs by the Interstate Renewable Energy Council for the U.S. Department of Energy. The data was collected from licensed contractors, PV practitioners, educators and expert instructors at training sessions, and at focus group and advisory committee meetings. Respondents were primarily from three states: Florida, New York and California. Other states were represented, but to a lesser extent. For data collection, a 12-item questionnaire was developed that addressed key workforce development issues from the perspectives of both the PV industry and training institutions. A total of 63 responses were collected, although not every respondent answered every question. Industry representatives slightly outnumbered the educators, although the difference in responses was not significant.
Date: April 1, 2009
Creator: Ventre, Jerry & Weissman, Jane
Object Type: Article
System: The UNT Digital Library
Risks of transportation along various routes to the Nevada Test Site. (open access)

Risks of transportation along various routes to the Nevada Test Site.

Residents of Southern Nevada have expressed interest in the risks posed by transportation of radioactive materials to the Nevada Test Site for disposal. Residents of the urban sections of Clark County, in particular, are concerned because the trucks carrying this material pass through fairly densely populated areas on both primary and secondary highways. Excellent studies by the Desert Research Institute (Miller, et al, 2005; 2007) measured the external radiation doses from these trucks and provided a benchmark for estimating the doses sustained by the population along the transportation routes. The studies did not, however, assess the doses to the population in the event of an accident involving these trucks. The present study estimates doses to the population along these routes and to various individual receptors, both for routine, incident-free transportation and for transportation accidents.
Date: April 1, 2009
Creator: Weiner, Ruth F.
Object Type: Report
System: The UNT Digital Library
Airflow Simulations around OA Intake Louver with Electronic Velocity Sensors (open access)

Airflow Simulations around OA Intake Louver with Electronic Velocity Sensors

It is important to control outdoor airflow rates into HVAC systems in terms of energy conservation and healthy indoor environment. Technologies are being developed to measure outdoor air (OA) flow rates through OA intake louvers on a real time basis. The purpose of this paper is to investigate the airflow characteristics through an OA intake louver numerically in order to provide suggestions for sensor installations. Airflow patterns are simulated with and without electronic air velocity sensors within cylindrical probes installed between louver blades or at the downstream face of the louver. Numerical results show quite good agreements with experimental data, and provide insights regarding measurement system design. The simulations indicate that velocity profiles are more spatially uniform at the louver outlet relative to between louver blades, that pressure drops imposed by the sensor bars are smaller with sensor bars at the louver outlet, and that placement of the sensor bars between louver blades substantially increases air velocities inside the louver. These findings suggest there is an advantage to placing the sensor bars at the louver outlet face.
Date: April 1, 2009
Creator: Han, Hwataik; Sullivan, Douglas P. & Fisk, William J.
Object Type: Article
System: The UNT Digital Library
Task 2: Boiler Corrosion, (open access)

Task 2: Boiler Corrosion,

For continued use of coal for power generation, there are needs to: –Improve efficiency –Decrease emissions (esp. CO2) –Use alternate fuels or fuel mixes
Date: April 1, 2009
Creator: Holcomb, G. R.; Covino, B. S., Jr.; Shim, H.-S.; Davis, K.; Eden, D. A.; White, M. et al.
Object Type: Article
System: The UNT Digital Library
Low Probability Tail Event Analysis and Mitigation in BPA Control Area: Task One Report (open access)

Low Probability Tail Event Analysis and Mitigation in BPA Control Area: Task One Report

This is a report for task one of the tail event analysis project for BPA. Tail event refers to the situation in a power system when unfavorable forecast errors of load and wind are superposed onto fast load and wind ramps, or non-wind generators falling short of scheduled output, the imbalance between generation and load becomes very significant. This type of events occurs infrequently and appears on the tails of the distribution of system power imbalance; therefore, is referred to as tail events. This report analyzes what happened during the Electric Reliability Council of Texas (ERCOT) reliability event on February 26, 2008, which was widely reported because of the involvement of wind generation. The objective is to identify sources of the problem, solutions to it and potential improvements that can be made to the system. Lessons learned from the analysis include the following: (1) Large mismatch between generation and load can be caused by load forecast error, wind forecast error and generation scheduling control error on traditional generators, or a combination of all of the above; (2) The capability of system balancing resources should be evaluated both in capacity (MW) and in ramp rate (MW/min), and be procured accordingly to …
Date: April 1, 2009
Creator: Lu, Shuai & Makarov, Yuri V.
Object Type: Report
System: The UNT Digital Library
DC Pro Software Tool Suite, Data Center Fact Sheet, Industrial Technologies Program (open access)

DC Pro Software Tool Suite, Data Center Fact Sheet, Industrial Technologies Program

This fact sheet describes how DOE's Data Center Energy Profiler (DC Pro) Software Tool Suite and other resources can help U.S. companies identify ways to improve the efficiency of their data centers.
Date: April 1, 2009
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Opto-electrical characterization and X-ray mapping of large-volume cadmium zinc telluride radiation detectors (open access)

Opto-electrical characterization and X-ray mapping of large-volume cadmium zinc telluride radiation detectors

Large-volume cadmium zinc telluride (CZT) radiation detectors would greatly improve radiation detection capabilities and, therefore, attract extensive scientific and commercial interests. CZT crystals with volumes as large as hundreds of centimeters can be achieved today due to improvements in the crystal growth technology. However, the poor performance of large-volume CZT detectors is still a challenging problem affecting the commercialization of CZT detectors and imaging arrays. We have employed Pockels effect measurements and synchrotron X-ray mapping techniques to investigate the performance-limiting factors for large-volume CZT detectors. Experimental results with the above characterization methods reveal the non-uniform distribution of internal electric field of large-volume CZT detectors, which help us to better understand the responsible mechanism for the insufficient carrier collection in large-volume CZT detectors.
Date: April 13, 2009
Creator: Yang, G.; Bolotnikov, A.E.; Camarda, G.S.; Cui, Y.; Hossain, A.; Yao, H.W. et al.
Object Type: Article
System: The UNT Digital Library
Low-Cost Substrates for High-Performance Nanorod Array LEDs (open access)

Low-Cost Substrates for High-Performance Nanorod Array LEDs

The completed project, entitled “Low-Cost Substrates for High-Performance Nanorod LEDs,” targeted the goal of a phosphor-free nanorod-based white LED with IQE > 50% across the spectrum from 450 nm to 600 nm on metallized silicon substrates. The principal achievements of this project included: • Demonstration of (In,Ga)N nanopyramid heterostructures by a conventional OMVPE process. • Verification of complete filtering of threading dislocations to yield dislocation-free pyramidal heterostructures. • Demonstration of electroluminescence with a peak wavelength of ~600 nm from an (In,Ga)N nanopyramid array LED. • Development of a reflective ZrN/AlN buffer layer for epitaxial growth of GaN films and GaN nanopyramid arrays on (111)Si.
Date: April 30, 2009
Creator: Sands, Timothy; Stach, Eric & Garcia, Edwin
Object Type: Report
System: The UNT Digital Library
Summary Report on Information Technology Integration Activities For project to Enhance NASA Tools for Coastal Managers in the Gulf of Mexico and Support Technology Transfer to Mexico (open access)

Summary Report on Information Technology Integration Activities For project to Enhance NASA Tools for Coastal Managers in the Gulf of Mexico and Support Technology Transfer to Mexico

Deliverable to NASA Stennis Space Center summarizing summarizes accomplishments made by Battelle and its subcontractors to integrate NASA's COAST visualization tool with the Noesis search tool developed under the Gulf of Mexico Regional Collaborative project.
Date: April 27, 2009
Creator: Gulbransen, Thomas C.
Object Type: Report
System: The UNT Digital Library
13.2 nm Table-Top Inspection Microscope for Extreme Ultraviolet Lithography Mask Defect Characterization (open access)

13.2 nm Table-Top Inspection Microscope for Extreme Ultraviolet Lithography Mask Defect Characterization

We report on a reflection microscope that operates at 13.2-nm wavelength with a spatial resolution of 55{+-}3 nm. The microscope uses a table-top EUV laser to acquire images of photolithography masks in 20 seconds.
Date: April 7, 2009
Creator: Brizuela, F.; Wang, Y.; Brewer, C.; Pedaci, F.; Chao, W.; Anderson, E. et al.
Object Type: Article
System: The UNT Digital Library
Plasma Simulation Using Gyrokinetic-Gyrofluid Hybrid Models (open access)

Plasma Simulation Using Gyrokinetic-Gyrofluid Hybrid Models

We are developing kinetic ion models for the simulation of extended MHD phenomena. The model they have developed uses full Lorentz force ions, and either drift-kinetic or gyro-kinetic electrons. Quasi-neutrality is assumed and the displacement current is neglected. They are also studying alpha particle driven Toroidal Alfven Eigenmodes (TAE) in the GEM gyrokinetic code [Chen 07]. The basic kinetic ion MHD model was recently reported in an invited talk given by Dan Barnes at the 2007 American Physical Society - Division of Plasma Physics (APS-DPP) and it has been published [Jones 04, Barnes 08]. The model uses an Ohm's law that includes the Hall term, pressure term and the electron inertia [Jones 04]. These results focused on the ion physics and assumed an isothermal electron closure. It is found in conventional gyrokinetic turbulence simulations that the timestep cannot be made much greater than the ion cyclotron period. However, the kinetic ion MHD model has the compressional mode, which further limits the timestep. They have developed an implicit scheme to avoid this timestep constraint. They have also added drift kinetic electrons. This model has been benchmarked linearly. Waves investigated where shear and compressional Alfven, whisterl, ion acoustic, and drift waves, including …
Date: April 9, 2009
Creator: Parker, Scott
Object Type: Report
System: The UNT Digital Library
UNCERTAINTY IN THE GLOBAL FORECAST SYSTEM (open access)

UNCERTAINTY IN THE GLOBAL FORECAST SYSTEM

We validated one year of Global Forecast System (GFS) predictions of surface meteorological variables (wind speed, air temperature, dewpoint temperature, air pressure) over the entire planet for forecasts extending from zero hours into the future (an analysis) to 36 hours. Approximately 12,000 surface stations world-wide were included in this analysis. Root-Mean-Square- Errors (RMSE) increased as the forecast period increased from zero to 36 hours, but the initial RMSE were almost as large as the 36 hour forecast RMSE for all variables. Typical RMSE were 3 C for air temperature, 2-3mb for sea-level pressure, 3.5 C for dewpoint temperature and 2.5 m/s for wind speed. Approximately 20-40% of the GFS errors can be attributed to a lack of resolution of local features. We attribute the large initial RMSE for the zero hour forecasts to the inability of the GFS to resolve local terrain features that often dominate local weather conditions, e.g., mountain- valley circulations and sea and land breezes. Since the horizontal resolution of the GFS (about 1{sup o} of latitude and longitude) prevents it from simulating these locally-driven circulations, its performance will not improve until model resolution increases by a factor of 10 or more (from about 100 km to …
Date: April 15, 2009
Creator: Werth, D. & Garrett, A.
Object Type: Article
System: The UNT Digital Library
The REBUS-MCNP Linkage. (open access)

The REBUS-MCNP Linkage.

The Reduced Enrichment Research and Test Reactor (RERTR) Program uses the REBUS-PC computer code to provide reactor physics and core design information such as neutron flux distributions in space, energy, and time, and to track isotopic changes in fuel and neutron absorbers with burnup. REBUS-PC models the complete fuel cycle including shuffling capability. REBUS-PC evolved using the neutronic capabilities of multi-group diffusion theory code DIF3D 9.0, but was extended to apply the continuous energy Monte Carlo code MCNP for one-group fluxes and cross-sections. The linkage between REBUS-PC and MCNP has recently been modernized and extended, as described in this manual. REBUS-PC now calls MCNP via a system call so that the user can apply any valid MCNP executable. The interface between REBUS-PC and MCNP requires minimal changes to an existing MCNP model, and little additional input. The REBUS-MCNP interface can also be used in conjunction with DIF3D neutronics to update an MCNP model with fuel compositions predicted using a DIF3D based depletion.
Date: April 24, 2009
Creator: Stevens, J. G.
Object Type: Report
System: The UNT Digital Library
Escapement and Productivity of Spring Chinook Salmon and Summer Steelhead in the John Day River Basin, 2005-2006 Annual Technical Report. (open access)

Escapement and Productivity of Spring Chinook Salmon and Summer Steelhead in the John Day River Basin, 2005-2006 Annual Technical Report.

The objectives are: (1) Estimate number and distribution of spring Chinook salmon Oncorhynchus tshawytscha redds and spawners in the John Day River subbasin; and (2) Estimate smolt-to-adult survival rates (SAR) and out-migrant abundance for spring Chinook and summer steelhead O. mykiss and life history characteristics of summer steelhead. The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, remain depressed relative to historic levels. Between the completion of the life history and natural escapement study in 1984 and the start of this project in 1998, spring Chinook spawning surveys did not provide adequate information to assess age structure, progeny-to-parent production values, smolt-to-adult survival (SAR), or natural spawning escapement. Further, only very limited information is available for steelhead life history, escapement, and productivity measures in the John Day subbasin. Numerous habitat protection and rehabilitation projects to improve salmonid freshwater production and survival have also been implemented in the basin and are in need of effectiveness monitoring. While our monitoring efforts outlined here will not specifically measure the effectiveness of any particular project, they will provide much needed background information for developing context …
Date: April 10, 2009
Creator: Schultz, Terra Lang; Wilson, Wayne H. & Ruzycki, James R.
Object Type: Report
System: The UNT Digital Library
Effective Size Analysis of the Diametral Compression (Brazil) Test Specimen (open access)

Effective Size Analysis of the Diametral Compression (Brazil) Test Specimen

This study considers the finite element analysis (FEA) simulation and Weibull effective size analysis for the diametral compression (DC) or Brazil specimen loaded with three different push-rod geometries. Those geometries are a flat push-rod, a push-rod whose radius of curvature is larger than that for the DC specimen, and a push-rod whose radius of curvature matches that of the DC specimen. Such established effective size analysis recognizes that the tensile strength of structural ceramics is typically one to two orders of magnitude less than its compressive strength. Therefore, because fracture is much more apt to result from a tensile stress than a compressive one, this traditional analysis only considers the first principal tensile stress field in the mechanically loaded ceramic component for the effective size analysis. The effective areas and effective volumes were computed as function of Weibull modulus using the CARES/Life code. Particular attention was devoted to the effect of mesh sensitivity and localized stress concentration. The effect of specimen width on the stress state was also investigated. The effects of push-rod geometry, the use of steel versus WC push-rods, and considering a frictionless versus no-slip interface between push-rod and specimen on the maximum stresses, where those stresses are …
Date: April 1, 2009
Creator: Jadaan, Osama M. & Wereszczak, Andrew A.
Object Type: Report
System: The UNT Digital Library
Modeling Mechanical Behavior of a Prismatic Replaceable Reflector Block (open access)

Modeling Mechanical Behavior of a Prismatic Replaceable Reflector Block

This report outlines the development of finite element models used to determine temperature and stresses in a prismatic core reflector block. This initial analysis determines an appropriate temperature distribution in a prismatic reflector from limiting conditions in the adjacent fuel block based on simplifying assumptions.
Date: April 1, 2009
Creator: Bratton, Robert
Object Type: Report
System: The UNT Digital Library
100 Area D4 Project Building Completion Report - July 2007 to December 2008 (open access)

100 Area D4 Project Building Completion Report - July 2007 to December 2008

This report documents the decontamination, decommissioning, and demolition of the 105-NB, 163-N, 183-N, 183-NA, 183-NB, 183-NC, 184-N, 184-NA, 184-NB, 184-NC, 184-ND, 184-NE, 184-NF, 1312-N, 1330-N, 1705-N, 1705-NA, 1706-N, 1712-N, 1714-N, 1714-NA, 1714-NB, 1802-N, MO-050, MO-055, MO-358, MO-390, MO-900, MO-911, and MO-950 facilities in the 100 Area of the Hanford Site. The D4 activities for these facilities include utility disconnection, planning, characterization, engineering, removal of hazardous and radiological contaminated materials, equipment removal, decommissioning, deactivation, decontamination, demolition of the structure, and removal of the remaining slabs.
Date: April 15, 2009
Creator: Stankovich, M. T.
Object Type: Report
System: The UNT Digital Library
Eddy covariance observations of surface leakage during shallow subsurface CO2 releases (open access)

Eddy covariance observations of surface leakage during shallow subsurface CO2 releases

We tested the ability of eddy covariance (EC) to detect, locate, and quantify surface CO{sub 2} flux leakage signals within a background ecosystem. For 10 days starting on 07/09/2007, and for seven days starting on 08/03/2007, 0.1 (Release 1) and 0.3 (Release 2) t CO{sub 2}d{sup -1}, respectively, were released from a horizontal well {approx}100 m in length and {approx}2.5 m in depth located in an agricultural field in Bozeman, MT. An EC station measured net CO{sub 2} flux (F{sub c}) from 06/08/2006 to 09/04/2006 (mean and standard deviation = -12.4 and 28.1 g m{sup -2} d{sup -1}, respectively) and from 05/28/2007 to 09/04/2007 (mean and standard deviation = -12.0 and 28.1 g m{sup -2} d{sup -1}, respectively). The Release 2 leakage signal was visible in the F{sub c} time series, whereas the Release 1 signal was difficult to detect within variability of ecosystem fluxes. To improve detection ability, we calculated residual fluxes (F{sub cr}) by subtracting fluxes corresponding to a model for net ecosystem exchange from F{sub c}. F{sub cr} had reduced variability and lacked the negative bias seen in corresponding F{sub c} distributions. Plotting the upper 90th percentile F{sub cr} versus time enhanced the Release 2 leakage signal. …
Date: April 1, 2009
Creator: Lewicki, J. L.; Hilley, G. E.; Fischer, M. L.; Pan, L.; Oldenburg, C. M.; Dobeck, L. et al.
Object Type: Article
System: The UNT Digital Library
Diagnosis of Solar Water Heaters Using Solar Storage Tank Surface Temperature Data: Preprint (open access)

Diagnosis of Solar Water Heaters Using Solar Storage Tank Surface Temperature Data: Preprint

Study of solar water heaters by using surface temperature data of solar storage tanks to diagnose proper operations.
Date: April 1, 2009
Creator: Burch, J.; Magnuson, L.; Barker, G. & Bullwinkel, M.
Object Type: Article
System: The UNT Digital Library