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Title: Assessing the Performance of 5mm White LED Light Sources forDeveloping-Country Applications

Abstract

Some white light-emitting diode (LED) light sources haverecently attained levels of efficiency and cost that allow them tocompete with fluorescent lighting for off-grid applications in thedeveloping world. Additional attributes (optics, size, ruggedness, andservice life) make them potentially superior products. Enormousreductions in energy use and greenhouse-gas emissions are thus possible,and system costs can be much lower given the ability to downsize thecharging and energy storage components compared to a fluorescentstrategy. However, there is a high risk of "market-spoiling" if inferiorproducts are introduced and result in user dissatisfaction. Completesystems involve the integration of light sources and optics, energysupply, and energy storage. A natural starting point for evaluatingproduct quality is to focus on the individual light sources. This reportdescribes testing results for batches of 10 5mm white LEDs from 26manufacturers. Efficacies and color properties are presented.

Authors:
Publication Date:
Research Org.:
Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
Sponsoring Org.:
USDOE
OSTI Identifier:
923294
Report Number(s):
LBNL-62620
R&D Project: E67001; BnR: 830404000; TRN: US200806%%404
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
32; 29; AVAILABILITY; COLOR; EFFICIENCY; ENERGY STORAGE; LIGHT EMITTING DIODES; LIGHT SOURCES; MANUFACTURERS; OPTICS; PERFORMANCE; SERVICE LIFE; TESTING

Citation Formats

Mills, Evan. Assessing the Performance of 5mm White LED Light Sources forDeveloping-Country Applications. United States: N. p., 2007. Web. doi:10.2172/923294.
Mills, Evan. Assessing the Performance of 5mm White LED Light Sources forDeveloping-Country Applications. United States. doi:10.2172/923294.
Mills, Evan. Thu . "Assessing the Performance of 5mm White LED Light Sources forDeveloping-Country Applications". United States. doi:10.2172/923294. https://www.osti.gov/servlets/purl/923294.
@article{osti_923294,
title = {Assessing the Performance of 5mm White LED Light Sources forDeveloping-Country Applications},
author = {Mills, Evan},
abstractNote = {Some white light-emitting diode (LED) light sources haverecently attained levels of efficiency and cost that allow them tocompete with fluorescent lighting for off-grid applications in thedeveloping world. Additional attributes (optics, size, ruggedness, andservice life) make them potentially superior products. Enormousreductions in energy use and greenhouse-gas emissions are thus possible,and system costs can be much lower given the ability to downsize thecharging and energy storage components compared to a fluorescentstrategy. However, there is a high risk of "market-spoiling" if inferiorproducts are introduced and result in user dissatisfaction. Completesystems involve the integration of light sources and optics, energysupply, and energy storage. A natural starting point for evaluatingproduct quality is to focus on the individual light sources. This reportdescribes testing results for batches of 10 5mm white LEDs from 26manufacturers. Efficacies and color properties are presented.},
doi = {10.2172/923294},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu May 03 00:00:00 EDT 2007},
month = {Thu May 03 00:00:00 EDT 2007}
}

Technical Report:

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