Halogen MR16 lamps are a mainstay of commercial and residential interior lighting and LED replacement lamps are making headway in improving their performance compared with halogens but with less success than other lamp categories collected in the EERE’s LED Lighting Facts database. The U.S. Department of Energy (DOE) office of Energy Efficiency and Renewable Energy (EERE) released a snapshot update on the progress of LED MR16s by looking at the performance specifications of the products in the Lighting Facts database. What it found was that even though LED penetration in MR16s is among the highest for any of DOE’s categories, they account for a diminishing share of the overall database. More importantly, MR16s show a slower rate of improvement in most key performance measures than other types of LED lamps.
The number of lighting products overall listed by LED Lighting Facts has approximately tripled in the past two years, but the number of listed MR16 lamps has not changed significantly, though many products have been added and others removed.
The increase in mean efficacy is about half of that seen for other categories, and lumen output or CBCP have not notably increased in recent years, either. In part the disparity in efficacy gains comes from strong improvements in other categories, most notably linear lamps or TLEDs.
“Given the limitations of the MR16 form factor and need for high color quality, the market may be dictating that the energy performance improvements are a secondary consideration to cost-competitiveness, CBCP [a measure of center beam intensity], and perhaps light output. Still, efficacy improvements can help alleviate thermal-management challenges associated with the small form factor, for example, which may help a true 50 W halogen MR16 equivalent to emerge,” the report said.
The DOE’s 2014 Snapshot on MR16s noted that the lumen output and center beam intensity of LED MR16s had been steadily increasing, but there were still few products that could claim to be truly comparable to a 50W halogen MR16.
“Two years later, the story is still the same. A handful of products have offered higher output and CBCP than the maximum in 2013, but no lamps meet the ENERGY STAR expected CBCP for a given beam angle. Likewise, efficacy increases for MR16s have been slow, with the mean efficacy only increasing from 54 lm/W to 61 lm/W over the past two years — the lowest efficacy of any major category of products listed by LED Lighting Facts.
Beginning in 2017, the Energy Star minimum efficacy requirements will be substantially higher, with tiers dependent on CRI. Only 25% of the currently active LED MR16 products will meet the new criteria when it takes effect. Over 97% of active products meet the current criteria.
More interesting facts about the LED Lighting Facts database in this paper:
The rate of increase in in the number of luminaires listed continues to outpace growth in lamps and retrofit kits. 25,000 lighting products were in the database as of July 1, 2015, and another 8,000 were added in the following five months.
The mean efficacy for all products continues to grow at a steady rate of approximately 10 lm/W per year. The range for the middle 50% of products is also increasing at a similar rate.
The number of very-high-efficacy products has steadily grown. Nearly 50 currently listed products exceed 150 lm/W. These products include industrial fixtures, troffers, linear fixtures, roadway fixtures, and linear lamps. They come from a number of manufacturers, and almost all have a CRI greater than 80 and vary between 3000 K and 5000 K.
At a given wattage, line-voltage halogen MR16 lamps (120 V) typically have lower lumen output than their low-voltage counterparts.
Here's where you read or download your own copy:CALiPER Snapshot MR16 Lamps