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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 217 records · Page 12
All sourcesNASA NTRSDOE OSTI
DOE OSTI2019

Printed Anodes and Internal Light Extraction Layers on Flexible Glass to Create Cost Effective and High Efficacy Bendable OLED Lighting Panels

In this project, OLEDWorks developed a high efficacy and cost-effective flexible OLED lighting system which could reduce the cost of OLED light by introducing a combination of printable and scalable scattering type internal light extraction (ILE) and transparent conductive silver nanowire technologies that are compatible with roll-to-roll (R2R) processing methods. High efficacy was achieved by co-optimization of the internal light extraction, silver nanowire and ITO anodes, and stacked white OLED structure to reduce unwanted absorption, increase the outcoupling efficiency, and lower the OLED voltage. At the end of Phase I of this project a power efficacy of 90 lm/W was demonstrated in a flexible OLED lighting device based on ultrathin bendable glass. Without much additional work, the milestone of 100 lm/W is certainly within reach, and with further work on light extraction and white OLED materials, we believe 120 lm/W or higher is achievable within the next few years.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2018

Connected Lighting Systems Efficiency Study: PoE Cable Energy Losses, Part 2

This is the second report of an investigation into energy losses in Ethernet cables used between Power over Ethernet (PoE) switches and luminaires in PoE connected lighting systems. Testing for Part 2 of the study was conducted in DOE’s Connected Lighting Test Bed in July and August 2018 and was a continuation of Part 1 studies conducted there in September 2017.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Accelerated Stress Testing of Multi-Source LED Products: Round 2

The second report in a series that uses accelerated stress testing (AST) to provide insights into the long-term behavior of commercial products utilizing different types of mid-power LEDs (MP-LEDs) integrated into the same LED module. The first report in the series provides initial AST results from two commercial lamps intended for use in horticulture applications and one tunable-white LED module intended for use in educational and office lighting applications. The second report focuses on determining the mechanisms of optical change in the same products.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2016

Characterizing Photometric Flicker

The focus of this study is simply to report on the commercial availability and performance of emerging flicker meters. Commercial-meter measurements and calculations were compared against those generated by a photoelectric characterization system developed by the Pacific Northwest National Laboratory (PNNL). The results and analysis show that the three commercially available flicker meters evaluated for this study measured light-intensity waveforms and calculated essential flicker-performance characteristics and metrics similarly, both to each other and to the reference meter chosen as an accuracy benchmark. Some differences in performance were found, however, when measurements were taken of light-intensity waveforms with significant high-frequency content – greater than the dominant 120 Hz found in many products at full output. Such conditions may be found in light sources that employ pulse-width modulation to achieve their target light output (e.g., intensity or color). If the meter was not appropriately configured (e.g., sampling frequency was too low), or if proper configuration was not possible given meter constraints (e.g., maximum number of available data points), then the waveform characteristics were not accurately captured, often resulting in the calculation of flicker metrics that deviated significantly from the reference.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2017

An Investigation of LED Street Lighting’s Impact on Sky Glow

A study of the expected contributions to sky glow from converting high-pressure sodium (HPS) street lighting to broader-spectrum (i.e., white light) sources, with specific focus on LEDs, which presents the contributions in a manner relative to HPS baseline conditions. These conditions represent typical conversions in the U.S. and include changes in spectral power distribution, percent uplight, and lumen output.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Measuring Light Exposure and its Effects on Sleep and Behavior in Care Center Residents [ACC Care Center - Sacramento, CA]

A study of tunable lighting at the ACC Care Center, a 99-bed nursing center in Sacramento, CA, with a large population of dementia patients. The study involved a partnership between experts in lighting design, environmental design, and light measurement; experts in measuring resident behavioral outcomes in nursing centers; and leaders from a nursing center with previously installed programmable, tunable LED lighting. The objective was to test a strategy for measuring and documenting light exposure for typical nursing-center residents, and to evaluate the data in terms of various metrics for human circadian responses over the course of a day. The study builds on a prior field evaluation of tunable lighting at the ACC Care Center.

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DOE OSTI2020

2019 Lighting R&D Opportunities

BTO’s Lighting R&D Opportunities is updated annually and covers foundational R&D needs for lighting technology and lighting application understanding that will result in maximum energy savings while also optimizing for building occupant well-being and productivity.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

Round 3 Update of Stress Testing Results for Organic Light-Emitting Diode Panels and Luminaires

Organic light-emitting diode (OLED) sources are a potential solid-state lighting technology for use in indoor lighting applications. Some of the advantages offered by OLEDs include thin profiles, low glare, diffuse lighting, and unique form factors. The U.S. Department of Energy (DOE) has released six technical reports focused on OLED technologies to provide information and analysis to the lighting industry. These reports include the evaluation of two different field deployment sites, a market analysis, a tear-down analysis, and two independent assessments of the performance of select commercially available OLED products. This report builds on earlier DOE efforts with OLED technology by updating information about previously benchmarked commercial OLED products. Specifically, this report provides updated findings about the robustness and reliability of commercial OLED products.

42 ENGINEERING↗
DOE OSTI2020

Specifying Calibration of Energy-Measuring Equipment

A report on calibrating energy-measuring equipment to maximize energy efficiency of lighting and other systems. The report describes best practices for accrediting calibration laboratories and for calibrating measuring equipment, compares and contrasts service providers accredited for energy-measuring equipment calibration, presents a tailorable specification template for requesting such calibration, and offers recommendations to a range of stakeholders.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2020

An Authentication Vulnerability Assessment of Connected Lighting Systems

Emerging connected lighting systems (CLS) that incorporate distributed intelligence, network interfaces, and sensors can become data-collection platforms that enable a wide range of valuable new capabilities as well as greater energy savings in buildings and cities. However, CLS technology is currently at an early stage of development, and its increased connectivity introduces cybersecurity risks that are new to the lighting industry and that must be addressed for successful integration with other systems. While a number of existing frameworks, guidelines, and tests for evaluating cybersecurity vulnerability may apply to CLS in whole or in part, there is currently no mandatory requirement for cybersecurity testing or certification. The lighting industry, including technology developers and specification organizations, is currently evaluating the suitability of existing frameworks and guidelines for CLS. To support these efforts, Pacific Northwest National Laboratory (PNNL) is conducting a series of studies intended to educate lighting industry stakeholders on specific cybersecurity practices and characterize their implementation in commercially available CLS with varying system architectures, network-communication technologies, and degrees of maturity. This study demonstrates that tests for authentication vulnerabilities can be developed with objective pass/fail criteria, therby facilitating comparisons between CLS. Based on the limited results of this study, it appears that the CLS that are being brought to market have varying levels of authentication vulnerability. It is hoped that these evaluations will support and perhaps accelerate industry discussions on the risks of specific security vulnerabilities, what vulnerabilities should be addressed by in-development of future lighting-specific best practices, and whether any such practices should be included in voluntary lighting standards.

42 ENGINEERING↗
DOE OSTI2019

Accelerated Stress Testing of Multi-Source LED Products; Round 2

Second report in a series that uses accelerated stress testing (AST) to provide insights into the long-term behavior of commercial products utilizing different types of mid-power LEDs (MP-LEDs) integrated into the same LED module. The first report in the series provides initial AST results from two commercial lamps intended for use in horticulture applications and one tunable-white LED module intended for use in educational and office lighting applications. The second report focuses on determining the mechanisms of optical change in the same products.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2018

Round 2 Update of Stress Testing Results for Organic Light-Emitting Diode Panels and Luminaires

Organic light-emitting diode (OLED) sources are a potential solid-state lighting technology for use in indoor lighting applications. Some of the advantages offered by OLEDs include thin profiles, low glare, diffuse lighting, and unique form factors. The U.S. Department of Energy (DOE) has released five reports about OLED technologies to provide information and analysis to the lighting industry. These reports include the evaluation of two different field deployment sites, a market analysis, and two independent assessments of the performance of select commercially available OLED products. This report builds on earlier DOE efforts with OLED technology by updating information about previously benchmarked OLED products (i.e., the Chalina luminaire from Acuity Brands and the Brite 2 and Brite Amber panels from OLEDWorks) in accelerated stress tests (ASTs). In addition, this report also provides an initial analysis of the performance of recently released OLED products—the Brite 3 panels from OLEDWorks.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2019

Energy Saving Opportunity from Advanced LED Lighting Research

Pacific Northwest National Laboratory (PNNL) was asked by the U.S. Department of Energy (DOE) to estimate the energy saving opportunity made possible by certain lighting research planned by PNNL. This report describes the results of that effort. To complete this work, PNNL selected a methodology created for and used in the electric utility industry, called Non-Energy Benefits methodology, and a lighting market model created for DOE to estimate future energy savings potential from solid-state lighting. The study found that select planned PNNL lighting research could lead to annual energy savings of 10% of total lighting energy savings in the year 2035, or in absolute terms, 334 tBtu. Energy savings in earlier years are smaller, primarily due to the early years of low market uptake of the new technologies expected from PNNL lighting research. In 2030, annual energy savings are projected to be 4.5%, or 165 tBtu.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2024

Graph learning for particle accelerator operations

Particle accelerators play a crucial role in scientific research, enabling the study of fundamental physics and materials science, as well as having important medical applications. This study proposes a novel graph learning approach to classify operational beamline configurations as good or bad. By considering the relationships among beamline elements, we transform data from components into a heterogeneous graph. We propose to learn from historical, unlabeled data via our self-supervised training strategy along with fine-tuning on a smaller, labeled dataset. Additionally, we extract a low-dimensional representation from each configuration that can be visualized in two dimensions. Leveraging our ability for classification, we map out regions of the low-dimensional latent space characterized by good and bad configurations, which in turn can provide valuable feedback to operators. This research demonstrates a paradigm shift in how complex, many-dimensional data from beamlines can be analyzed and leveraged for accelerator operations.

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DOE OSTI2016

High Brightness OLED Lighting

In this work we describe the technology developments behind our current and future generations of high brightness OLED lighting panels. We have developed white and amber OLEDs with excellent performance based on the stacking approach. Current products achieve 40-60 lm/W, while future developments focus on achieving 80 lm/W or higher.

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