The US Department of Energy (DOE) has announced the completion of the Series 18 testing of a group of 17 LED recessed wallwasher luminaires. The results indicate that, while some LED recessed wallwashers are already competitive with conventional products, improvements can be made in several areas.
The 17 LEDs tested had a wide variety of physical attributes, and had a similar diversity in lumen output and luminous intensity distribution. The lumen output from each of the products was generally equivalent to luminaires using up to 42W compact fluorescent light (CFL) or 35W ceramic metal halide (CML) lamps. CALiPER did not test any LED products that exceeded 1,800 lumens, although LED products with higher output could exist.
The average efficacy of the products tested was 42 lm/W, though the products had efficacies that ranged between 23 and 64 lm/W. Most of the products fell between the CALiPER CFL and CMH benchmarks, while only three products measured at more than 52 lm/W, the most efficacious benchmark tested.
Only 9 of the 17 LED recessed wallwashers that were tested met the DesignLights Consortium (DLC) qualified products list minimum efficacy requirement of 40 lm/W, and only 7 products would meet current ENERGY STAR efficacy requirement for downlights of 42 lm/W, if they applied. Among LED products the efficacy of the wallwashers is below average, but that is generally true of wallwashers based on any light source as the product class exhibits poor efficiency. The LED products, however, have the potential to improve in efficacy.
Each of the products tested had a CRI between 76 and 92, with 13 of the 17 products having a CRI above 80. This level of performance is generally seen as acceptable for architectural interiors, but more demanding applications may require use of products at the higher end of the range. CRI is an area where LED recessed wallwashers could improve.
The performance claims of the manufactuers were an issue for four of the products tested. These four products delivered less than 90% of the lumens claimed by the manufacturer. Of these, two products performed especially poorly, with one delivering 14% and the other 65%. The other products were all within 10% of the claimed lumen output, except one which delivered 14% more lumens than claimed.
