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PVWatts (R) Calculator India (Fact Sheet) (open access)

PVWatts (R) Calculator India (Fact Sheet)

The PVWatts (R) Calculator for India was released by the National Renewable Energy Laboratory in 2013. The online tool estimates electricity production and the monetary value of that production of grid-connected roof- or ground-mounted crystalline silicon photovoltaics systems based on a few simple inputs. This factsheet provides a broad overview of the PVWatts (R) Calculator for India.
Date: January 1, 2014
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Extracting TMDs from CLAS12 data (open access)

Extracting TMDs from CLAS12 data

We present studies of double longitudinal spin asymmetries in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator, which includes quark intrinsic transverse momentum within the generalized parton model based on the fully differential cross section for the process. Additionally we employ Bessel-weighting to the MC events to extract transverse momentum dependent parton distribution functions and also discuss possible uncertainties due to kinematic correlation effects.
Date: January 1, 2014
Creator: Aghasyan, Mher M. & Avakian, Harut A.
Object Type: Article
System: The UNT Digital Library

Results of Second Outdoor Comparison Between Absolute Cavity Pyrgeometer (ACP) and Infrared Integrating Sphere (IRIS) Radiometer at PMOD

The Absolute Cavity Pyrgeometer (ACP) and InfraRed Integrating Sphere radiometer (IRIS) are developed to establish a world reference for calibrating pyrgeometers with traceability to SI units. The two radiometers are un-windowed with negligible spectral dependence, and traceable to SI units through the temperature scale (ITS-90). The second outdoor comparison between the two designs was held from September 30 to October 11, 2013 at the Physikalisch-Metorologisches Observatorium Davos (PMOD). The difference between the irradiance measured by ACP and that of the IRIS was within 1 W/m2 (3 IRISs: PMOD + Australia + Germany). From the first and second comparisons, a difference of 4-6 W/m2 was observed between the irradiance measured by ACP&IRIS and that of the interim World Infrared Standard Group (WISG). This presentation includes results from the first and second comparison in an effort to establish the world reference for pyrgeometer calibrations, a key deliverable for the World Meteorological Organization (WMO), and the DOE-ASR.
Date: January 1, 2014
Creator: Reda, I.; Grobner, J. & Wacker, S.
Object Type: Presentation
System: The UNT Digital Library

Treatment of Solar Generation in Electric Utility Resource Planning

Today's utility planners have a different market and economic context than their predecessors, including planning for the growth of renewable energy. Through interviews and a questionnaire, the authors gathered information on utility supply planning and how solar is represented. Utilities were asked to provide their resource planning process details, key assumptions (e.g. whether DG is represented as supply or negative load), modeling methodology (e.g. type of risk analytics and candidate portfolio development), capacity expansion and production simulation model software, and solar project representation (project size, capacity value and integration cost adder). This presentation aims to begin the exchange of information between utilities, regulators and other stakeholders by capturing utility-provided information about: 1) how various utilities approach long-range resource planning; 2) methods and tools utilities use to conduct resource planning; and, 3) how solar technologies are considered in the resource planning process.
Date: January 1, 2014
Creator: Cory, K.; Sterling, J.; Taylor, M. & McLaren, J.
Object Type: Presentation
System: The UNT Digital Library
New model for nucleon generalized parton distributions (open access)

New model for nucleon generalized parton distributions

We describe a new type of models for nucleon generalized parton distributions (GPDs) H and E. They are heavily based on the fact nucleon GPDs require to use two forms of double distribution (DD) representations. The outcome of the new treatment is that the usual DD+D-term construction should be amended by an extra term, {xi} E{sub +}{sup 1} (x,{xi}) which has the DD structure {alpha}/{beta} e({beta},{alpha}, with e({beta},{alpha}) being the DD that generates GPD E(x,{xi}). We found that this function, unlike the D-term, has support in the whole -1 <= x <= 1 region. Furthermore, it does not vanish at the border points |x|={xi}.
Date: January 1, 2014
Creator: Radyushkin, Anatoly V.
Object Type: Article
System: The UNT Digital Library
Beta Test Plan for Advanced Inverters Interconnecting Distributed Resources with Electric Power Systems (open access)

Beta Test Plan for Advanced Inverters Interconnecting Distributed Resources with Electric Power Systems

This document provides a preliminary (beta) test plan for grid interconnection systems of advanced inverter-based DERs. It follows the format and methodology/approach established by IEEE Std 1547.1, while incorporating: 1. Upgraded tests for responses to abnormal voltage and frequency, and also including ride-through. 2. A newly developed test for voltage regulation, including dynamic response testing. 3. Modified tests for unintentional islanding, open phase, and harmonics to include testing with the advanced voltage and frequency response functions enabled. Two advanced inverters, one single-phase and one three-phase, were tested under the beta test plan. These tests confirmed the importance of including tests for inverter dynamic response, which varies widely from one inverter to the next.
Date: January 1, 2014
Creator: Hoke, A.; Chakraborty, S.; Basso, T. & Coddington, M.
Object Type: Report
System: The UNT Digital Library
Contribution of Road Grade to the Energy Use of Modern Automobiles Across Large Datasets of Real-World Drive Cycles: Preprint (open access)

Contribution of Road Grade to the Energy Use of Modern Automobiles Across Large Datasets of Real-World Drive Cycles: Preprint

Understanding the real-world power demand of modern automobiles is of critical importance to engineers using modeling and simulation to inform the intelligent design of increasingly efficient powertrains. Increased use of global positioning system (GPS) devices has made large scale data collection of vehicle speed (and associated power demand) a reality. While the availability of real-world GPS data has improved the industry's understanding of in-use vehicle power demand, relatively little attention has been paid to the incremental power requirements imposed by road grade. This analysis quantifies the incremental efficiency impacts of real-world road grade by appending high fidelity elevation profiles to GPS speed traces and performing a large simulation study. Employing a large real-world dataset from the National Renewable Energy Laboratory's Transportation Secure Data Center, vehicle powertrain simulations are performed with and without road grade under five vehicle models. Aggregate results of this study suggest that road grade could be responsible for 1% to 3% of fuel use in light-duty automobiles.
Date: January 1, 2014
Creator: Wood, E.; Burton, E.; Duran, A. & Gonder, J.
Object Type: Article
System: The UNT Digital Library

Rolling Element Bearing Stiffness Matrix Determination

Current theoretical bearing models differ in their stiffness estimates because of different model assumptions. In this study, a finite element/contact mechanics model is developed for rolling element bearings with the focus of obtaining accurate bearing stiffness for a wide range of bearing types and parameters. A combined surface integral and finite element method is used to solve for the contact mechanics between the rolling elements and races. This model captures the time-dependent characteristics of the bearing contact due to the orbital motion of the rolling elements. A numerical method is developed to determine the full bearing stiffness matrix corresponding to two radial, one axial, and two angular coordinates; the rotation about the shaft axis is free by design. This proposed stiffness determination method is validated against experiments in the literature and compared to existing analytical models and widely used advanced computational methods. The fully-populated stiffness matrix demonstrates the coupling between bearing radial, axial, and tilting bearing deflections.
Date: January 1, 2014
Creator: Guo, Y. & Parker, R.
Object Type: Presentation
System: The UNT Digital Library
Transportation Secure Data Center: Real-World Data for Planning, Modeling, and Analysis (Fact Sheet) (open access)

Transportation Secure Data Center: Real-World Data for Planning, Modeling, and Analysis (Fact Sheet)

This fact sheet describes the Transportation Secure Data Center (TSDC) - an NREL-operated resource that provides secure access to detailed GPS travel data for valuable research purposes in a way that protects original participant privacy.
Date: January 1, 2014
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Fueling Robot Automates Hydrogen Hose Reliability Testing (Fact Sheet) (open access)

Fueling Robot Automates Hydrogen Hose Reliability Testing (Fact Sheet)

Automated robot mimics fueling action to test hydrogen hoses for durability in real-world conditions.
Date: January 1, 2014
Creator: Harrison, K.
Object Type: Report
System: The UNT Digital Library
Corrective Action Decision Document/Closure Report for Corrective Action Unit 105: Area 2 Yucca Flat Atmospheric Test Sites, Nevada National Security Site, Nevada, Revision 1 (open access)

Corrective Action Decision Document/Closure Report for Corrective Action Unit 105: Area 2 Yucca Flat Atmospheric Test Sites, Nevada National Security Site, Nevada, Revision 1

The purpose of this Corrective Action Decision Document/Closure Report is to provide justification and documentation supporting the recommendation that no further corrective action is needed for CAU 105 based on the implementation of the corrective actions. Corrective action investigation (CAI) activities were performed from October 22, 2012, through May 23, 2013, as set forth in the Corrective Action Investigation Plan for Corrective Action Unit 105: Area 2 Yucca Flat Atmospheric Test Sites; and in accordance with the Soils Activity Quality Assurance Plan, which establishes requirements, technical planning, and general quality practices.
Date: January 1, 2014
Creator: Matthews, Patrick
Object Type: Report
System: The UNT Digital Library

Testing Low-Energy, High-Power Energy Storage Alternatives in a Full-Hybrid Vehicle

Automakers have been mass producing hybrid electric vehicles (HEVs) for well over a decade, and the technology has proven to be very effective at reducing per-vehicle gasoline use. However, the battery cost in HEVs contribute to higher incremental cost of HEVs (a few thousand dollars) than the cost of comparable conventional vehicles, which has limited HEV market penetration. Significant cost reductions/performance improvements to the energy storage system (ESS) can improve the vehicle-level cost vs. benefit relationship for HEVs. Such an improvement could lead to larger HEV market penetration and greater aggregate gasoline savings. After significant analysis by the National Renewable Energy Laboratory (NREL), the United States Advanced Battery Consortium (USABC) and Department of Energy (DOE) Energy Storage program suggested a new set of requirements for ESS for power-assist HEVs for cost reduction without impacting performance and fuel economy significantly. With support from DOE, NREL has developed an HEV test platform for in-vehicle performance and fuel economy validation testing of the hybrid system using such LEESS devices. This poster will describe development of the LEESS HEV test platform, and LEESS laboratory as well as in-vehicle evaluation results. The first LEESS technology tested was lithium-ion capacitors (LICs) - i.e., asymmetric electrochemical energy …
Date: January 1, 2014
Creator: Cosgrove, J. & Gonger, J.
Object Type: Presentation
System: The UNT Digital Library
Technique Reveals Critical Physics in Deep Regions of Solar Cells (Fact Sheet) (open access)

Technique Reveals Critical Physics in Deep Regions of Solar Cells (Fact Sheet)

NREL's improved time-resolved photoluminescence method measures minority-carrier lifetime deep within photovoltaic samples to help develop more efficient solar cells.
Date: January 1, 2014
Creator: unknown
Object Type: Report
System: The UNT Digital Library

Transition Form Factors: A Unique Opportunity to Connect #11;Non-Perturbative Strong Interactions to QCD

Meson-photoproduction measurements and their reaction-amplitude analyses can establish more sensitively, and in some cases in an almost model-independent way, nucleon excitations and non-resonant reaction amplitudes. However, to investigate the strong interaction from explored — where meson-cloud degrees of freedom contribute substantially to the baryon structure — to still unexplored distance scales — where quark degrees of freedom dominate and the transition from dressed to current quarks occurs — we depend on experiments that allow us to measure observables that are probing this evolving non-perturbative QCD regime over its full range. Elastic and transition form factors are uniquely suited to trace this evolution by measuring elastic electron scattering and exclusive single-meson and double-pion electroproduction cross sections off the nucleon. These exclusive measurements will be extended to higher momentum transfers with the energy-upgraded CEBAF beam at JLab to study the quark degrees of freedom, where their strong interaction is responsible for the ground and excited nucleon state formations. After establishing unprecedented high-precision data, the imminent next challenge is a high-quality analysis to extract these relevant electrocoupling parameters for various resonances that then can be compared to state-of-the-art models and QCD-based calculations. Recent results will demonstrate the status of the analysis and of …
Date: January 1, 2014
Creator: Gothe, Ralf W.
Object Type: Presentation
System: The UNT Digital Library
Assessment of Offshore Wind System Design, Safety, and Operation Standards (open access)

Assessment of Offshore Wind System Design, Safety, and Operation Standards

This report is a deliverable for a project sponsored by the U.S. Department of Energy (DOE) entitled National Offshore Wind Energy Resource and Design Data Campaign -- Analysis and Collaboration (contract number DE-EE0005372; prime contractor -- AWS Truepower). The project objective is to supplement, facilitate, and enhance ongoing multiagency efforts to develop an integrated national offshore wind energy data network. The results of this initiative are intended to 1) produce a comprehensive definition of relevant met-ocean resource assets and needs and design standards, and 2) provide a basis for recommendations for meeting offshore wind energy industry data and design certification requirements.
Date: January 1, 2014
Creator: Sirnivas, S.; Musial, W.; Bailey, B. & Filippelli, M.
Object Type: Report
System: The UNT Digital Library
Time Domain Partitioning of Electricity Production Cost Simulations (open access)

Time Domain Partitioning of Electricity Production Cost Simulations

Production cost models are often used for planning by simulating power system operations over long time horizons. The simulation of a day-ahead energy market can take several weeks to compute. Tractability improvements are often made through model simplifications, such as: reductions in transmission modeling detail, relaxation of commitment variable integrality, reductions in cost modeling detail, etc. One common simplification is to partition the simulation horizon so that weekly or monthly horizons can be simulated in parallel. However, horizon partitions are often executed with overlap periods of arbitrary and sometimes zero length. We calculate the time domain persistence of historical unit commitment decisions to inform time domain partitioning of production cost models. The results are implemented using PLEXOS production cost modeling software in an HPC environment to improve the computation time of simulations while maintaining solution integrity.
Date: January 1, 2014
Creator: Barrows, C.; Hummon, M.; Jones, W. & Hale, E.
Object Type: Report
System: The UNT Digital Library
National Clean Fleets Partnership (Fact Sheet) (open access)

National Clean Fleets Partnership (Fact Sheet)

Clean Cities' National Clean Fleets Partnership establishes strategic alliances with large fleets to help them explore and adopt alternative fuels and fuel economy measures to cut petroleum use. The initiative leverages the strength of nearly 100 Clean Cities coalitions, nearly 18,000 stakeholders, and more than 20 years of experience. It provides fleets with top-level support, technical assistance, robust tools and resources, and public acknowledgement to help meet and celebrate fleets' petroleum-use reductions.
Date: January 1, 2014
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Shorepower Truck Electrification Project (STEP) - 2013 (Fact Sheet) (open access)

Shorepower Truck Electrification Project (STEP) - 2013 (Fact Sheet)

The Fleet Test and Evaluation Team at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) is evaluating and documenting the use of shorepower at 50 planned American Recovery and Reinvestment Act (ARRA)-funded truck stop electrification sites across the nation. Trucks participating in the study have idle-reduction equipment installed that was purchased with rebates through the ARRA. A total of 5,000 rebates will be approved.
Date: January 1, 2014
Creator: unknown
Object Type: Report
System: The UNT Digital Library
First JAM results on the determination of polarized parton distributions (open access)

First JAM results on the determination of polarized parton distributions

The Jefferson Lab Angular Momentum (JAM) Collaboration is a new initiative to study the angular momentum dependent structure of the nucleon. First results on the determination of spin-dependent parton distribution functions at intermediate and large x from world data on polarized deep-inelastic scattering are presented. Different aspects of global QCD analysis are discussed, including the effects of nuclear structure of deuterium and {sup 3}He targets, target mass corrections and higher twist contributions to the g{sub 1} and g{sub 2} structure functions.
Date: January 1, 2014
Creator: Accardi, Alberto; Jimenez-Delgado, Pedro & Melnitchouk, Wally
Object Type: Article
System: The UNT Digital Library
Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control (open access)

Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

The DOE Building America program has been conducting research leading to cost effective high performance homes since the early 1990's. Optimizing whole house mechanical ventilation as part of the program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this white paper is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.
Date: January 1, 2014
Creator: Martin, E.
Object Type: Report
System: The UNT Digital Library

The Wind Integration National Dataset (WIND) toolkit

Regional wind integration studies require detailed wind power output data at many locations to perform simulations of how the power system will operate under high penetration scenarios. The wind datasets that serve as inputs into the study must realistically reflect the ramping characteristics, spatial and temporal correlations, and capacity factors of the simulated wind plants, as well as being time synchronized with available load profiles.As described in this presentation, the WIND Toolkit fulfills these requirements by providing a state-of-the-art national (US) wind resource, power production and forecast dataset.
Date: January 1, 2014
Creator: Draxl, Caroline
Object Type: Presentation
System: The UNT Digital Library
Active Power Controls from Wind Power: Bridging the Gaps (open access)

Active Power Controls from Wind Power: Bridging the Gaps

This paper details a comprehensive study undertaken by the National Renewable Energy Laboratory, Electric Power Research Institute, and the University of Colorado to understand how the contribution of wind power providing active power control (APC) can benefit the total power system economics, increase revenue streams, improve the reliability and security of the power system, and provide superior and efficient response while reducing any structural and loading impacts that may reduce the life of the wind turbine or its components. The study includes power system simulations, control simulations, and actual field tests using turbines at NREL's National Wind Technology Center (NWTC). The study focuses on synthetic inertial control, primary frequency control, and automatic generation control, and analyzes timeframes ranging from milliseconds to minutes to the lifetime of wind turbines, locational scope ranging from components of turbines to large wind plants to entire synchronous interconnections, and additional topics ranging from economics to power system engineering to control design.
Date: January 1, 2014
Creator: Ela, E.; Gevorgian, V.; Fleming, P.; Zhang, Y. C.; Singh, M.; Muljadi, E. et al.
Object Type: Report
System: The UNT Digital Library
Geochemical and Geomechanical Effects on Wellbore Cement Fractures: Data Information for Wellbore Reduced Order Model (open access)

Geochemical and Geomechanical Effects on Wellbore Cement Fractures: Data Information for Wellbore Reduced Order Model

The primary objective of the National Risk Assessment Partnership (NRAP) program is to develop a defensible, generalized, and science-based methodology and platform for quantifying risk profiles at CO2 injection and storage sites. The methodology must incorporate and define the scientific basis for assessing residual risks associated with long-term stewardship and help guide site operational decision-making and risk management. Development of an integrated and risk-based protocol will help minimize uncertainty in the predicted long-term behavior of the CO2 storage site and thereby increase confidence in storage integrity. The risk profile concept has proven useful in conveying the qualitative evolution of risks for CO2 injection and storage site. However, qualitative risk profiles are not sufficient for specifying long-term liability for CO2 storage sites. Because there has been no science-based defensible and robust methodology developed for quantification of risk profiles for CO2 injection and storage, NRAP has been focused on developing a science-based methodology for quantifying risk profiles for various risk proxies.
Date: January 1, 2014
Creator: Um, Wooyong; Jung, Hun Bok; Kabilan, Senthil; Suh, Dong-Myung & Fernandez, Carlos A.
Object Type: Report
System: The UNT Digital Library
Analyzing Effects of Turbulence on Power Generation Using Wind Plant Monitoring Data: Preprint (open access)

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

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 power 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 …
Date: January 1, 2014
Creator: Zhang, J.; Chowdhury, S. & Hodge, B. M.
Object Type: Article
System: The UNT Digital Library