The technology improvements in LED technology should extend to all LED lamps and fixtures. However, that was not found to be the case with MR16 LED lamps.
The U.S. Department of Energy’s CALiPER program has published a new Snapshot Report on LED MR16 lamps. The new Snapshot report updates a similar Snapshot Report that DOE published in January 2014. Snapshot reports focus on five core metrics: lumen output, input power, luminous efficacy, color rendering index, and correlated color temperature.The report revealed that the LED technology in MR16 LED lamps only marginally improved in the two years since the 2014 report. In that same time frame, LED technology has progressed rapidly overall with large improvements in efficacy in luminaires of various LED fixtures and lamps.
The report revealed that the LED technology in MR16 LED lamps only marginally improved in the two years since the 2014 report. As an industry, we can do better.
In that same time frame LED technology has progressed rapidly overall with large improvements in efficacy in luminaires of various LED fixtures and lamps.
However, the technology for LED-based MR16 lamps has apparently stagnated, according to the report. While the efficacy of LED-based MR16 lamps improved some, the increase in mean efficacy is only about half of that seen for other categories of luminaires and lamps. The DOE found that MR16 lumen output and center beam intensity (CBCP) hadn’t notably increased in recent years either. At a given beam angle, still none of the listed lamps meet the expected CBCP values for a 50W halogen MR16 using the ENERGY STAR® calculator. However, several now meet the minimum threshold that ENERGY STAR requires for claiming equivalency to a 50W halogen MR16.
The report revealed that number of MR16s listed by LED Lighting Facts® hasn’t changed much in four years. For this reason, MR16 LED lamps represent a dwindling percentage of the total number of LED Lighting Facts-listed lamps. The report noted that technically, the LED Lighting Facts list of products is not a statistical sample of the overall market.
One of the few positives in the report is that the market penetration for LED MR16s is among the highest for any product category. The DOE notes that this is likely due to the MR16 halogen lamp being an early target for LED lighting developers. So the technology has been on the market for a long time.
According to the report, the efficacy of MR16s currently are the lowest of any major category of products listed by LED Lighting Facts. The DOE found that the percentage of MR16 lamps that meet ENERGY STAR criteria for color rendering and color temperature has increased compared to two years ago. Power factors of MR16 lamps have made small gains.
The report acknowledged that certain performance considerations are not necessarily revealed in the metrics that the Snapshot report examined. For example, MR16 lamps require an integral driver that needs to fit into the form factor. Also, in most applications, the driver must operate at 12 V. The voltage of the driver necessitates the use of a transformer. Notably, compatibility issues can result from using combinations of drivers and transformers degrading performance in one or more areas (e.g., flicker). Sometimes tradeoffs must be made, such as between flicker and power quality.
The report speculates that because of limitations of the MR16 form factor and the need for high color quality, the market may be dictating that improvements in energy performance are a secondary consideration to cost-competitiveness, CBCP, and perhaps light output.
The DOE intends to focus on the long-term performance of MR16 LED lamps in future Snapshot reports.
Ideally, the industry should continue to improve efficacy levels, output, power factor, and center beam candle power for MR16 lamps to at least equal the performance of the best Halogen MR16 lamps. While the market may have less financial incentive to continue improving MR16 LED technology, the engineering community should still have an inherent mandate to continue improving. Ever better, ever brighter, and ever more efficient!
