This page contains links to technical reports and briefs published by the U.S. Department of Energy, plus information on current studies under way. These reports are intended to present objective technical analysis based on the most recent, referenceable data available at the time of preparation of the reports. As new information becomes available, DOE will make efforts to update these studies as necessary. While coordinated with other DOE data sources and policies, these reports also include data from a variety of non-governmental sources in order to produce, to the extent possible, unbiased analysis. These reports are intended solely for the benefit of the public, in order to help regulators, manufacturers, energy program managers, and others make informed choices and decisions related to solid-state lighting. Readers of these reports are urged to conduct their own due diligence and research before using the analysis presented in these reports.
Dim-to-Warm LED Lighting: Initial Benchmarks
Provides a methodology to characterize performance and assess potential reliability issues of dim-to-warm LED lamp products, as well as comparisons with an incandescent lamp benchmark. (35 pages, July 2019)
- Accelerated Stress Testing of Multi-Source LED Products
A report 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.
- Accelerated Stress Testing of Multi-Source LED Products: Horticulture Lamps and Tunable-White Modules (54 pages, March 2018)
- Accelerated Stress Testing of Multi-Source LED Products: Round 2 (59 pages, July 2019)
- Accelerated Stress Testing Results on Single-Channel and Multichannel Drivers
A three-part series on driver robustness. The first report provides initial accelerated stress testing (AST) results for both single-channel and multichannel drivers, and the second report is an interim update on the performance of multichannel drivers in AST. The third report summarizes overall findings from up to 7,500 hours of AST on two-stage SSL drivers that could be used to operate troffers and similar fixtures.
- Part 1: Initial Results of Accelerated Stress Testing on Single-Channel and Multichannel Drivers (47 pages, February 2018 — Revised June 2018)
- Part 2: Accelerated Stress Testing on Multichannel Drivers — Updated Test Results (32 pages, May 2018)
- Part 3: Accelerated Stress Testing Results on Single-Channel and Multichannel Drivers: Final Report (44 pages, February 2019)
Round 2 Update of Stress Testing Results for Organic Light-Emitting Diode Panels and Luminaires
A report that provides updated 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. In addition, this report also provides an initial analysis of the performance of recently released OLED products—the Brite 3 panels from OLEDWorks. (51 pages, December 2018)
Luminous Flux and Chromaticity Maintenance for Select High-Power Color Light-Emitting Diodes
A report that describes findings from a review of LM-80-15 data of color LEDs in high-power LED packages in order to provide insights regarding the current state of color LEDs. (29 pages, July 2018)
LED Luminaire Reliability: Impact of Color Shift
Provides an understanding of chromaticity shift and its impact on the performance of LED lighting products. (27 pages, April 2017)
- True Colors
A technical brief about spectral emission of LEDs and the relationship between correlated color temperature, color rendering index, optical safety, material degradation, and photobiological stimulation. (8 pages, October 2014)
- Hammer Testing Findings for Solid-State Lighting Luminaires
Provides findings from the DOE LED Systems Reliability Consortium Hammer Test on commercial SSL luminaires, a highly accelerated life test method intended to produce failures in SSL luminaires in a reasonable test period, and provide insight into potential failure modes. (48 pages, December 2013)
- Lumen Maintenance and Light Loss Factors: Consequences of Current Design Practices for LEDs
This article, from the IES journal LEUKOS, discusses the complications related to lamp lumen depreciation (LLD) and LEDs, compares the performance of some conventional and LED products, and examines alternatives to the current recommended approach for determining LLDs for LED products. (December 2013)
- Life-Cycle Assessment of Energy and Environmental Impacts of LED Lighting Products
This three-part DOE study assesses the life-cycle environmental and resource costs in the manufacturing, transport, use, and disposal of LED lighting products in relation to comparable traditional lighting technologies.
- Part 1: Review of the Life-Cycle Energy Consumption of Incandescent, Compact Fluorescent, and LED Lamps (54 pages, February 2012—Updated August 2012)
- Part 2: LED Manufacturing and Performance (79 pages, June 2012)
- Part 3: LED Environmental Testing (211 pages, March 2013)
- Complete Report Summary
- Accounting for Uncertainty in Lumen Measurements
This study provides a detailed and step-by-step method for determining uncertainty in lumen measurements, working closely with related standards efforts and key industry experts. This report uses the structure proposed in the Guide to Uncertainty Measurements (GUM) for evaluating and expressing uncertainty in measurements. (35 pages, March 2011)