233 Matching Results

Results open in a new window/tab.

Development of ZnTe:Cu Contacts for CdTe Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-08-320 (open access)

Development of ZnTe:Cu Contacts for CdTe Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-08-320

The main focus of the work at NREL was on the development of Cu-doped ZnTe contacts to CdTe solar cells in the substrate configuration. The work performed under the CRADA utilized the substrate device structure used at NREL previously. All fabrication was performed at NREL. We worked on the development of Cu-doped ZnTe as well as variety of other contacts such as Sb-doped ZnTe, CuxTe, and MoSe2. We were able to optimize the contacts to improve device parameters. The improvement was obtained primarily through increasing the open-circuit voltage, to values as high as 760 mV, leading to device efficiencies of 7%.
Date: April 1, 2012
Creator: Dhere, R.
Object Type: Report
System: The UNT Digital Library
Delaware Energy and Cost Savings for New Single- and Multifamily Homes: 2012 IECC as Compared to the 2009 IECC (open access)

Delaware Energy and Cost Savings for New Single- and Multifamily Homes: 2012 IECC as Compared to the 2009 IECC

The 2012 International Energy Conservation Code (IECC) yields positive benefits for Delaware homeowners. Moving to the 2012 IECC from the 2009 IECC is cost effective over a 30-year life cycle. On average, Delaware homeowners will save $10,409 with the 2012 IECC. After accounting for upfront costs and additional costs financed in the mortgage, homeowners should see net positive cash flows (i.e., cumulative savings exceeding cumulative cash outlays) in 1 year for the 2012 IECC. Average annual energy savings are $616 for the 2012 IECC.
Date: April 1, 2012
Creator: Lucas, Robert G.; Taylor, Zachary T.; Mendon, Vrushali V. & Goel, Supriya
Object Type: Report
System: The UNT Digital Library
Measure Guideline: Transitioning from Three-Coat Stucco to One-Coat Stucco with EPS (open access)

Measure Guideline: Transitioning from Three-Coat Stucco to One-Coat Stucco with EPS

This Measure Guideline has been developed to help builders transition from using a traditional three-coat stucco wall-cladding system to a one-coat stucco wall-cladding system with expanded polystyrene (EPS) insulated sheathing. The three-coat system uses a base layer, a fill layer, and a finish layer. The one-coat system maintains the look of a traditional stucco system but uses only a base layer and a finish coat over EPS insulation that achieves higher levels of energy efficiency. Potential risks associated with the installation of a one-coat stucco system are addressed in terms of design, installation, and warranty concerns such as cracking and delamination, along with mitigation strategies to reduce these risks.
Date: April 1, 2012
Creator: Brozyna, K.; Davis, G. & Rapport, A.
Object Type: Report
System: The UNT Digital Library
Max Tech and Beyond: High-Intensity Discharge Lamps (open access)

Max Tech and Beyond: High-Intensity Discharge Lamps

High-intensity discharge (HID) lamps are most often found in industrial and commercial applications, and are the light source of choice in street and area lighting, and sports stadium illumination. HID lamps are produced in three types - mercury vapor (MV), high pressure sodium (HPS) and metal halide (MH). Of these, MV and MH are considered white-light sources (although the MV exhibits poor color rendering) and HPS produces a yellow-orange color light. A fourth lamp, low-pressure sodium (LPS), is not a HID lamp by definition, but it is used in similar applications and thus is often grouped with HID lamps. With the notable exception of MV which is comparatively inefficient and in decline in the US from both a sales and installed stock point of view; HPS, LPS and MH all have efficacies over 100 lumens per watt. The figure below presents the efficacy trends over time for commercially available HID lamps and LPS, starting with MV and LPS in 1930's followed by the development of HPS and MH in the 1960's. In HID lamps, light is generated by creating an electric arc between two electrodes in an arc tube. The particles in the arc are partially ionized, making them electrically …
Date: April 1, 2012
Creator: Scholand, Michael
Object Type: Report
System: The UNT Digital Library
In-Depth Look at Ground Source Heat Pumps and Other Electric Loads in Two GreenMax Homes (open access)

In-Depth Look at Ground Source Heat Pumps and Other Electric Loads in Two GreenMax Homes

CARB partnered with WPPI Energy to answer key research questions on in-field performance of ground-source heat pumps and LAMELs through extensive field monitoring at two WPPI GreenMax demonstration homes in Wisconsin. These two test home evaluations provided valuable data on the true in-field performance of various building mechanical systems and lighting, appliances, and miscellaneous loads (LAMELs).
Date: April 1, 2012
Creator: Puttagunta, S. & Shapiro, C.
Object Type: Report
System: The UNT Digital Library
Advanced Energy Design Guides Slash Energy Use in Schools and Retail Buildings by 50% (Fact Sheet) (open access)

Advanced Energy Design Guides Slash Energy Use in Schools and Retail Buildings by 50% (Fact Sheet)

Owners, contractors, engineers, and architects can easily achieve significant energy savings by leveraging the complex analyses and expertise captured in these guides.
Date: April 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
NREL Paves the Way to Commercialization of Silicon Ink (Fact Sheet) (open access)

NREL Paves the Way to Commercialization of Silicon Ink (Fact Sheet)

In 2008, Innovalight, a start-up company in Sunnyvale, California, invented a liquid form of silicon, called Silicon Ink. It contains silicon nanoparticles that are suspended evenly within the solution. Those nanoparticles contain dopant atoms that can be driven into silicon solar cells, which changes the conductivity of the silicon and creates the internal electric fields that are needed to turn photons into electrons -- and thus into electricity. The ink is applied with a standard screen printer, already commonly used in the solar industry. The distinguishing feature of Silicon Ink is that it can be distributed in exact concentrations in precisely the correct locations on the surface of the solar cell. This allows most of the surface to be lightly doped, enhancing its response to blue light, while heavily doping the area around the electrical contacts, raising the conductivity in that area to allow the contact to work more efficiently. The accuracy and uniformity of the ink distribution allows the production of solar cells that achieve higher power production at a minimal additional cost.
Date: April 1, 2012
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Gearbox Reliability Collaborative: Test and Model Investigation of Sun Orbit and Planet Load Share in a Wind Turbine Gearbox; Preprint (open access)

Gearbox Reliability Collaborative: Test and Model Investigation of Sun Orbit and Planet Load Share in a Wind Turbine Gearbox; Preprint

This paper analyzes experimental measurement of the sun gear orbit in dynamometer testing and describes its relation to the other measured responses of the planetary stage. The relation of the sun orbit to component runout, component flexibility, gear coupling alignment, planet load share, and planet position error will be investigated. Equations describing the orbit of the sun gear in the test cases are derived. Rigid and flexible multibody models of the full gearbox are investigated and compared to sun and planet measurements. This paper shows that the sun gear's path may be influenced by gear coupling responses and gearbox structural flexibilities.
Date: April 1, 2012
Creator: LaCava, W.; Keller, J. & McNiff, B.
Object Type: Article
System: The UNT Digital Library
Outdoor PV Module Degradation of Current-Voltage Parameters: Preprint (open access)

Outdoor PV Module Degradation of Current-Voltage Parameters: Preprint

Photovoltaic (PV) module degradation rate analysis quantifies the loss of PV power output over time and is useful for estimating the impact of degradation on the cost of energy. An understanding of the degradation of all current-voltage (I-V) parameters helps to determine the cause of the degradation and also gives useful information for the design of the system. This study reports on data collected from 12 distinct mono- and poly-crystalline modules deployed at the National Renewable Energy Laboratory (NREL) in Golden, Colorado. Most modules investigated showed < 0.5%/year decrease in maximum power due to short-circuit current decline.
Date: April 1, 2012
Creator: Smith, R. M.; Jordan, D. C. & Kurtz, S. R.
Object Type: Article
System: The UNT Digital Library
Simple intrinsic defects in InP : numerical predictions. (open access)

Simple intrinsic defects in InP : numerical predictions.

None
Date: April 1, 2012
Creator: Schultz, Peter Andrew
Object Type: Report
System: The UNT Digital Library
Vehicle Technologies' Fact of the Week 2011 (open access)

Vehicle Technologies' Fact of the Week 2011

Each week the U.S. Department of Energy s Vehicle Technology Program (VTP) posts a Fact of the Week on their website: http://www1.eere.energy.gov/vehiclesandfuels/. These Facts provide statistical information, usually in the form of charts and tables, on vehicle sales, fuel economy, gasoline prices, and other transportation-related trends. Each Fact is a stand-alone page that includes a graph, text explaining the significance of the data, the supporting information on which the graph was based, and the source of the data. A link to the current Fact is available Monday through Friday on the VTP homepage, but older Facts are archived and still available at: http://www1.eere.energy.gov/vehiclesandfuels/facts/. This report is a compilation of the Facts that were posted during calendar year 2011. The Facts were written and prepared by staff in Oak Ridge National Laboratory's Center for Transportation Analysis.
Date: April 1, 2012
Creator: Davis, Stacy Cagle; Diegel, Susan W & Boundy, Robert Gary
Object Type: Report
System: The UNT Digital Library
MiniGhost : a miniapp for exploring boundary exchange strategies using stencil computations in scientific parallel computing. (open access)

MiniGhost : a miniapp for exploring boundary exchange strategies using stencil computations in scientific parallel computing.

A broad range of scientific computation involves the use of difference stencils. In a parallel computing environment, this computation is typically implemented by decomposing the spacial domain, inducing a 'halo exchange' of process-owned boundary data. This approach adheres to the Bulk Synchronous Parallel (BSP) model. Because commonly available architectures provide strong inter-node bandwidth relative to latency costs, many codes 'bulk up' these messages by aggregating data into a message as a means of reducing the number of messages. A renewed focus on non-traditional architectures and architecture features provides new opportunities for exploring alternatives to this programming approach. In this report we describe miniGhost, a 'miniapp' designed for exploration of the capabilities of current as well as emerging and future architectures within the context of these sorts of applications. MiniGhost joins the suite of miniapps developed as part of the Mantevo project.
Date: April 1, 2012
Creator: Barrett, Richard Frederick; Heroux, Michael Allen & Vaughan, Courtenay Thomas
Object Type: Report
System: The UNT Digital Library
IMPROVED COMPUTATIONAL NEUTRONICS METHODS AND VALIDATION PROTOCOLS FOR THE ADVANCED TEST REACTOR (open access)

IMPROVED COMPUTATIONAL NEUTRONICS METHODS AND VALIDATION PROTOCOLS FOR THE ADVANCED TEST REACTOR

The Idaho National Laboratory (INL) is in the process of modernizing the various reactor physics modeling and simulation tools used to support operation and safety assurance of the Advanced Test Reactor (ATR). Key accomplishments so far have encompassed both computational as well as experimental work. A new suite of stochastic and deterministic transport theory based reactor physics codes and their supporting nuclear data libraries (HELIOS, KENO6/SCALE, NEWT/SCALE, ATTILA, and an extended implementation of MCNP5) has been installed at the INL. Corresponding models of the ATR and ATRC are now operational with all five codes, demonstrating the basic feasibility of the new code packages for their intended purpose. Of particular importance, a set of as-run core depletion HELIOS calculations for all ATR cycles since August 2009 was successfully completed during 2011. This demonstration supported a decision late in the year to proceed with the phased incorporation of the HELIOS methodology into the ATR fuel cycle management process beginning in 2012. On the experimental side of the project, new hardware was fabricated, measurement protocols were finalized, and the first four of six planned physics code validation experiments based on neutron activation spectrometry were conducted at the ATRC facility. Data analysis for the …
Date: April 1, 2012
Creator: Nigg, David W.; Nielsen, Joseph W.; Chase, Benjamin M.; Murray, Ronnie K. & Steuhm, Kevin A.
Object Type: Article
System: The UNT Digital Library
A new time-dependent analytic model for radiation-induced photocurrent in finite 1D epitaxial diodes. (open access)

A new time-dependent analytic model for radiation-induced photocurrent in finite 1D epitaxial diodes.

Photocurrent generated by ionizing radiation represents a threat to microelectronics in radiation environments. Circuit simulation tools such as SPICE [1] can be used to analyze these threats, and typically rely on compact models for individual electrical components such as transistors and diodes. Compact models consist of a handful of differential and/or algebraic equations, and are derived by making simplifying assumptions to any of the many semiconductor transport equations. Historically, many photocurrent compact models have suffered from accuracy issues due to the use of qualitative approximation, rather than mathematically correct solutions to the ambipolar diffusion equation. A practical consequence of this inaccuracy is that a given model calibration is trustworthy over only a narrow range of operating conditions. This report describes work to produce improved compact models for photocurrent. Specifically, an analytic model is developed for epitaxial diode structures that have a highly doped subcollector. The analytic model is compared with both numerical TCAD calculations, as well as the compact model described in reference [2]. The new analytic model compares well against TCAD over a wide range of operating conditions, and is shown to be superior to the compact model from reference [2].
Date: April 1, 2012
Creator: Verley, Jason C.; Axness, Carl L.; Hembree, Charles Edward; Keiter, Eric Richard & Kerr, Bert (New Mexico Institute of Mining and Technology, Socorro, NM)
Object Type: Report
System: The UNT Digital Library
Ion Exchange Kinetics Testing with SRF Resin (open access)

Ion Exchange Kinetics Testing with SRF Resin

The U.S. Department of Energy (DOE) Hanford Site contains more than 53 million gallons of legacy waste generated as a byproduct of plutonium production and reprocessing operations. The wastes are a complex mixture composed mostly of NaNO3, NaNO2, NaOH, NaAlO2, Na3PO4, and Na2SO4, with a number of minor and trace metals, organics, and radionuclides stored in underground waste tanks. The DOE Office of River Protection (ORP) has contracted Bechtel National Incorporated (BNI) to build a pretreatment facility, the River Protection Project-Waste Treatment Plant (RPP-WTP), that will separate long-lived transuranics (TRU) and highly radioactive components (specifically 137Cs and, in selected cases, 90Sr) from the bulk (non-radioactive) constituents and immobilize the wastes by vitrification. The plant is designed to produce two waste streams: a high-volume low-activity waste (LAW) and a low-volume high-activity waste (HLW).
Date: April 1, 2012
Creator: Russell, Renee L.; Rinehart, Donald E.; Brown, Garrett N.; Schonewill, Philip P. & Peterson, Reid A.
Object Type: Report
System: The UNT Digital Library
Deep Residential Retrofits in East Tennessee (open access)

Deep Residential Retrofits in East Tennessee

Executive Summary Oak Ridge National Laboratory (ORNL) is furthering residential energy retrofit research in the mixed-humid climate of East Tennessee by selecting 10 homes and guiding the homeowners in the energy retrofit process. The homeowners pay for the retrofits, and ORNL advises which retrofits to complete and collects post-retrofit data. This effort is in accordance with the Department of Energy s Building America program research goal of demonstrating market-ready energy retrofit packages that reduce home energy use by 30 50%. Through this research, ORNL researchers hope to understand why homeowners decide to partake in energy retrofits, the payback of home energy retrofits, and which retrofit packages most economically reduce energy use. Homeowner interviews help the researchers understand the homeowners experience. Information gathered during the interviews will aid in extending market penetration of home energy retrofits by helping researchers and the retrofit industry understand what drives homeowners in making positive decisions regarding these retrofits. This report summarizes the selection process, the pre-retrofit condition, the recommended retrofits, the actual cost of the retrofits (when available), and an estimated energy savings of the retrofit package using EnergyGauge . Of the 10 households selected to participate in the study, only five completed the recommended …
Date: April 1, 2012
Creator: Boudreaux, Philip R; Hendrick, Timothy P; Christian, Jeffrey E & Jackson, Roderick K
Object Type: Report
System: The UNT Digital Library
2012 Update of the Combination of CDF and D0 Results for the Mass of the W Boson (open access)

2012 Update of the Combination of CDF and D0 Results for the Mass of the W Boson

We summarize and combine the results on the direct measurements of the mass of the W boson in data collected by the Tevatron experiments CDF and D0 at Fermilab. Earlier results from CDF Run-0 (1988-1989), D0 and CDF Run-I (1992-1995) and D0 results from 1 fb{sup -1} (2002-2006) of Run-II data are now combined with two new, high statistics Run-II measurements: a CDF measurement in both electron and muon channels using 2.2 fb{sup -1} of integrated luminosity collected between 2002 and 2007, and a D0 measurement in the electron channel using 4.3 fb{sup -1} collected between 2006 and 2009. As in previous combinations, the results are corrected for inconsistencies in parton distribution functions and assumptions about electroweak parameters used in the different analyses. The resulting Tevatron average for the mass of the W boson is M{sub W} = 80,387 {+-} 16 MeV and a new world average including data from LEP II is M{sub W} = 80,385 {+-} 15 MeV.
Date: April 1, 2012
Creator: Tevatron Electroweak Working Group,
Object Type: Report
System: The UNT Digital Library
N*(1535) electroproduction at high Q2 (open access)

N*(1535) electroproduction at high Q2

A covariant spectator quark model is applied to study the {gamma}N {yields} N*(1535) reaction in the large Q{sup 2} region. Starting from the relation between the nucleon and N*(1535) systems, the N*(1535) valence quark wave function is determined without the addition of any parameters. The model is then used to calculate the {gamma}N {yields} N*(1535) transition form factors. A very interesting, useful relation between the A{sub 1/2} and S{sub 1/2} helicity amplitudes for Q{sup 2} > GeV{sup 2}, is also derived.
Date: April 1, 2012
Creator: G. Ramalho, M.T. Pena, K. Tsushima
Object Type: Article
System: The UNT Digital Library
An Assessment of Energy Potential at Non-Powered Dams in the United States (open access)

An Assessment of Energy Potential at Non-Powered Dams in the United States

fleet by 15%. A majority of this potential is concentrated in just 100 NPDs, which could contribute approximately 8 GW of clean, reliable hydropower; the top 10 facilities alone could add up to 3 GW of new hydropower. Eighty-one of the 100 top NPDs are U.S. Army Corps of Engineers (USACE) facilities, many of which, including all of the top 10, are navigation locks on the Ohio River, Mississippi River, Alabama River, and Arkansas River, as well as their major tributaries. This study also shows that dams owned by the U.S. Bureau of Reclamation hold the potential to add approximately 260 MW of capacity; the Bureau has also engaged in an effort to conduct a more detailed evaluation of its own facilities.
Date: April 1, 2012
Creator: Hadjerioua, Boualem; Wei, Yaxing & Kao, Shih-Chieh
Object Type: Report
System: The UNT Digital Library
National Energy and Cost Savings for New Single- and Multifamily Homes: A Comparison of the 2006, 2009, and 2012 Editions of the IECC (open access)

National Energy and Cost Savings for New Single- and Multifamily Homes: A Comparison of the 2006, 2009, and 2012 Editions of the IECC

The 2009 and 2012 International Energy Conservation Code (IECC) yield positive benefits for U.S. homeowners and significant energy savings for the nation. Moving from a baseline of the 2006 IECC to the 2009 IECC reduces average annual energy costs by 10.8%, while moving from the same baseline to the 2012 IECC reduces them by 32.1%. These reductions amount to annual energy cost savings of $168 and $497, respectively. The 2012 IECC saves $329 in energy costs compared to the 2009 IECC.
Date: April 1, 2012
Creator: Lucas, Robert G.; Taylor, Zachary T.; Mendon, Vrushali V. & Goel, Supriya
Object Type: Report
System: The UNT Digital Library
Integrating Variable Renewable Energy in Electric Power Markets: Best Practices from International Experience, Summary for Policymakers (open access)

Integrating Variable Renewable Energy in Electric Power Markets: Best Practices from International Experience, Summary for Policymakers

Many countries -- reflecting very different geographies, markets, and power systems -- are successfully managing high levels of variable renewable energy on the electric grid, including that from wind and solar energy. This document summarizes policy best practices that energy ministers and other stakeholders can pursue to ensure that electricity markets and power systems can effectively coevolve with increasing penetrations of variable renewable energy. There is no one-size-fits-all approach; each country studied has crafted its own combination of policies, market designs, and system operations to achieve the system reliability and flexibility needed to successfully integrate renewables. Notwithstanding this diversity, the approaches taken by the countries studied all coalesce around five strategic areas: lead public engagement, particularly for new transmission; coordinate and integrate planning; develop rules for market evolution that enable system flexibility; expand access to diverse resources and geographic footprint of operations; and improve system operations. This study also emphatically underscores the value of countries sharing their experiences. The more diverse and robust the experience base from which a country can draw, the more likely that it will be able to implement an appropriate, optimized, and system-wide approach.
Date: April 1, 2012
Creator: Cochran, J.; Bird, L.; Heeter, J. & Arent, D. A.
Object Type: Report
System: The UNT Digital Library
Application of the BISON Fuel Performance Code to the FUMEX-III Coordinated Research Project (open access)

Application of the BISON Fuel Performance Code to the FUMEX-III Coordinated Research Project

INL recently participated in FUMEX-III, an International Atomic Energy Agency sponsored fuel modeling Coordinated Research Project. A main purpose of FUMEX-III is to compare code predictions to reliable experimental data. During the same time period, the INL initiated development of a new multidimensional (2D and 3D) multiphysics nuclear fuel performance code called BISON. Interactions with international fuel modeling researchers via FUMEX-III played a significant and important role in the BISON evolution, particularly influencing the selection of material and behavioral models which are now included in the code. BISON's ability to model integral fuel rod behavior did not mature until 2011, thus the only FUMEX-III case considered was the Riso3-GE7 experiment, which includes measurements of rod outer diameter following pellet clad mechanical interaction (PCMI) resulting from a power ramp late in fuel life. BISON comparisons to the Riso3-GE7 final rod diameter measurements are quite reasonable. The INL is very interested in participation in the next Fuel Modeling Coordinated Research Project and would like to see the project initiated as soon as possible.
Date: April 1, 2012
Creator: Williamson, R. L. & Novascone, S. R.
Object Type: Report
System: The UNT Digital Library
Annual Performance Evaluation of a Pair of Energy Efficient Houses (WC3 and WC4) in Oak Ridge, TN (open access)

Annual Performance Evaluation of a Pair of Energy Efficient Houses (WC3 and WC4) in Oak Ridge, TN

Beginning in 2008, two pairs of energy-saver houses were built at Wolf Creek in Oak Ridge, TN. These houses were designed to maximize energy efficiency using new ultra-high-efficiency components emerging from ORNL s Cooperative Research and Development Agreement (CRADA) partners and others. The first two houses contained 3713 square feet of conditioned area and were designated as WC1 and WC2; the second pair consisted of 2721 square feet conditioned area with crawlspace foundation and they re called WC3 and WC4. This report is focused on the annual energy performance of WC3 and WC4, and how they compare against a previously benchmarked maximum energy efficient house of a similar footprint. WC3 and WC4 are both about 55-60% more efficient than traditional new construction. Each house showcases a different envelope system: WC3 is built with advanced framing featured cellulose insulation partially mixed with phase change materials (PCM); and WC4 house has cladding composed of an exterior insulation and finish system (EIFS). The previously benchmarked house was one of three built at the Campbell Creek subdivision in Knoxville, TN. This house (CC3) was designed as a transformation of a builder house (CC1) with the most advanced energy-efficiency features, including solar electricity and hot …
Date: April 1, 2012
Creator: Biswas, Kaushik; Christian, Jeffrey E; Gehl, Anthony C; Jackson, Roderick K & Boudreaux, Philip R
Object Type: Report
System: The UNT Digital Library
Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint (open access)

Absorber Alignment Measurement Tool for Solar Parabolic Trough Collectors: Preprint

As we pursue efforts to lower the capital and installation costs of parabolic trough solar collectors, it is essential to maintain high optical performance. While there are many optical tools available to measure the reflector slope errors of parabolic trough solar collectors, there are few tools to measure the absorber alignment. A new method is presented here to measure the absorber alignment in two dimensions to within 0.5 cm. The absorber alignment is measured using a digital camera and four photogrammetric targets. Physical contact with the receiver absorber or glass is not necessary. The alignment of the absorber is measured along its full length so that sagging of the absorber can be quantified with this technique. The resulting absorber alignment measurement provides critical information required to accurately determine the intercept factor of a collector.
Date: April 1, 2012
Creator: Stynes, J. K. & Ihas, B.
Object Type: Article
System: The UNT Digital Library