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Title: Measured Off-Grid LED Lighting System Performance

Abstract

This report is a product of our ongoing effort to support the development of high-quality yet affordable products for off-grid lighting in the developing world that have good potential to succeed in the market. The effort includes work to develop low-cost testing procedures, to identify useful performance metrics, and to facilitate the development of industry standards and product rating protocols. We conducted laboratory testing of nine distinct product lines. In some cases we also tested multiple generations of a single product line and/or operating modes for a product. The resultsare summarized in Table 1. We found that power consumption and light output varied by nearly a factor of 12, with efficacy varying by a factor of more than six. Of particular note, overall luminous efficacy varied from 8.2 to 53.1 lumens per watt. Color quality indices variedmaterially, especially for correlated color temperature. Maximum illuminance, beamcandlepower, and luminance varied by 8x, 32x, and 61x respectively, suggesting considerable differences among products in terms of service levels and visual comfort. Glare varied by1.4x, and was above acceptable thresholds in most cases. Optical losses play a role in overall performance, varying by a factor of 3.2 and ranging as high as 24percent. These findingsmore » collectively indicate considerable potential for improved product design.« less

Authors:
; ; ; ; ;
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
Environmental Energy Technologies Division
OSTI Identifier:
962705
Report Number(s):
LBNL-2025E
TRN: US200917%%90
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
32; COLOR; DESIGN; ILLUMINANCE; LIGHTING SYSTEMS; MARKET; METRICS; PERFORMANCE; TESTING; Off-grid lighting, development, energy, carbon

Citation Formats

Granderson, Jessica, Galvin, James, Bolotov, Dmitriy, Clear, Robert, Jacobson, Arne, and Mills, Evan. Measured Off-Grid LED Lighting System Performance. United States: N. p., 2008. Web. doi:10.2172/962705.
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Granderson, Jessica, Galvin, James, Bolotov, Dmitriy, Clear, Robert, Jacobson, Arne, & Mills, Evan. Measured Off-Grid LED Lighting System Performance. United States. doi:10.2172/962705.
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Granderson, Jessica, Galvin, James, Bolotov, Dmitriy, Clear, Robert, Jacobson, Arne, and Mills, Evan. Thu . "Measured Off-Grid LED Lighting System Performance". United States. doi:10.2172/962705. https://www.osti.gov/servlets/purl/962705.
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@article{osti_962705,
title = {Measured Off-Grid LED Lighting System Performance},
author = {Granderson, Jessica and Galvin, James and Bolotov, Dmitriy and Clear, Robert and Jacobson, Arne and Mills, Evan},
abstractNote = {This report is a product of our ongoing effort to support the development of high-quality yet affordable products for off-grid lighting in the developing world that have good potential to succeed in the market. The effort includes work to develop low-cost testing procedures, to identify useful performance metrics, and to facilitate the development of industry standards and product rating protocols. We conducted laboratory testing of nine distinct product lines. In some cases we also tested multiple generations of a single product line and/or operating modes for a product. The resultsare summarized in Table 1. We found that power consumption and light output varied by nearly a factor of 12, with efficacy varying by a factor of more than six. Of particular note, overall luminous efficacy varied from 8.2 to 53.1 lumens per watt. Color quality indices variedmaterially, especially for correlated color temperature. Maximum illuminance, beamcandlepower, and luminance varied by 8x, 32x, and 61x respectively, suggesting considerable differences among products in terms of service levels and visual comfort. Glare varied by1.4x, and was above acceptable thresholds in most cases. Optical losses play a role in overall performance, varying by a factor of 3.2 and ranging as high as 24percent. These findings collectively indicate considerable potential for improved product design.},
doi = {10.2172/962705},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Dec 18 00:00:00 EST 2008},
month = {Thu Dec 18 00:00:00 EST 2008}
}
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Technical Report:
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DOI:  10.2172/962705
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