Thursday, May 27, 2010

Latest DOE Testing Data on LED Products

The latest report - May 2010 - has just been issued from "The Department of Energy Commercially Available Light-Emitting Diode Product and Evaluation (CALiPER) Program".  

We have continued to question much of the hype regarding LED products.  The best source of true performance data comes from the tests being run by the DOE.   The latest findings support what we have been hearing from top scientists in lighting.  LEDs are having significant issues with size, true efficacy, life and led color degradation beginning very early on.  The report does not address one of the biggest issues - cost.

Summary of Results: Round 10 of Product Testing: "Smaller Replacement Lamps" DOE Solid State Lighting

Two out of four lamps tested "Two of the small replacement lamps, the PAR30L (09-96) and the A-lamp (09-98), did not meet ANSI-defined lamp format standards for the geometry of the lamp styles they are meant to replace. The PAR30L lamp was shorter than the required minimal overall lamp length, which could cause the lamp to be recessed inappropriately or not fit in some fixtures. The diameter of the neck of the A-lamp was too large and widening of the neck starts too close to the Edison base, which could result in the lamp not fitting in some fixtures. Respecting form factor standards is important for market acceptance as demonstrated by lessons learned from CFLs.25" (initial market failure).

Due to the large differences in performance between the submitted and purchased units, several attempts were made to purchase additional units for testing. In each case, the manufacturer indicated that the product was temporarily out of stock and would not be available for several months. The CALiPER results in this case raise a number of doubts.

The relatively high performance of sample 09-16 submitted by the manufacturer may indicate that it was hand-picked to significantly outperform others and is not representative of the typical performance of lamps in this product line.

The relatively poor performance of sample 09-107A as compared to the submitted sample may indicate inconsistently produced units of the product.

The apparent malfunctioning in sample 09-107B may indicate product design flaws or quality control issues.

The perpetual ‘out of stock’ status of the product may shed doubt on the general reliability of the product and on the longer-term integrity of the product warranty.

A 2010 report on CALiPER long-term testing shows that a wide range of behaviors in lumen depreciation and color maintenance can be observed across SSL luminaires and replacement lamps. None of the products included in CALiPER Round 10 have been tested for reliability at this time. 

Due to the range of behaviors and rapid rate of change of SSL technology, buyers and specifiers should be wary of all product life claims. More than half the SSL products subjected to CALiPER long-term testing will not provide 70% of initial light output at 50,000 hours and already exhibit significant color shift within the duration of the CALiPER long-term operation. About one quarter of the SSL products would not pass a simple 1000-hour operational test: they do not last as long as a traditional incandescent lamp.

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