DOE Snapshot Reveals Compelling Case for Fluorescent Replacement

The U.S. Department of Energy released its 2016 CALiPER Snapshot of LED-based troffers including luminaires and retrofit kits. The CALiPER Snapshot report found the efficacy of LED troffer luminaires and retrofit kits that were voluntarily submitted to be listed with the Lighting Facts database to be notably higher than that of fluorescent troffers that they replace.

Efficacy Distribution Comparison

While the efficacy of fluorescent troffers tops in the database tops out at 100 lumens per watt (LPW), the average efficacy of the LED troffers is 102 LPW. The Snapshot revealed that 56% of the listed LED troffers had efficacies of 100 LPW or higher. Also, about ten percent of the listed LED troffers have efficacies of 125 LPW and higher.

According to the Snapshot, the average efficacy increased 5 LPW in just the past six months, which is nearly equal to the rise in LPW for the entire previous year.

Luxeon High Power

Like the previous snapshot of 2014, the middle 50% occupied a narrow range. The average efficacy of the middle 50% of the listed LED products in the December 2016 Snapshot covers the relatively small range of 80-111 LPW.

The highest efficacy of the listed troffers is above 150 LPW. Among all the lighting facts database of products (46,105 — now not including replacement lamps), 350 exceed 150 LPW, which was the highest efficacy among all of the listed products just 18 months before.

The efficacy of the listed LED troffer products was found to be on par with that of LED-based linear and industrial fixtures and slightly higher than that of area/roadway and directional fixtures. It was also found to be substantially higher than the efficacy of downlight luminaires.

Output Distribution

A vast majority of the listed troffer products exceed the minimum lumen output requirements for DLC QPL qualification.

Although fewer LED retrofit products are among listed in the database, the range in their efficacy and output was found to be similar.

Not all of the troffers list a specific size designation. However, among those that do list the size of 2×2 and 2×4, they clearly had higher luminous efficacy than their fluorescent counterparts.

The efficacy and output of some of the LED products greatly exceed that of the fluorescent products and therefore exceeds the range of the charts.

These LED troffers with the best overall performance in terms of output and efficacy are likely industrial troffers which would be more glaring than those used in offices and classrooms.

The efficacy of TLEDs was multiplied by 0.8 (a very conservative estimate) to account for losses because of the fixture.

LED Troffer CCTs and CRIs

The distribution of LED troffers at 4000K and 5000K was roughly even with few luminaires being 3500K or lower. Few of the luminaires had models with 4500K CCT because it is non-standard CCT.

All of the retrofit kits and 89% of the troffers had CRIs above of 80 or more.

Case for Replacement or Retrofit

Overall, the Snapshot demonstrated that the performance and efficacy of LED troffers and retrofit kits makes a compelling case for replacing fluorescent fixtures.

However, projected lifetime and initial cost were not taken into account. Despite this, it is expected that the lifetimes of the listed products would considerably exceed that of the fluorescents, and the initial cost of the LED-based troffers would mostly be on par with fluorescent troffers.

So, if the total cost of ownership were taken into account, the case for replacing fluorescents with LEDs would probably be even stronger.