It’s tempting to think that LED bulbs are inherently state-of-the-art, relying as they do on a fairly young technology, but that’s not Philips 10W LED non-dim bulb the case. Many of the LED lights, especially those carried in the big box stores like Kmart and target, were designed several years ago, and their efficacy as well as color quality are sadly dated. So the recent US Department of Energy CALiPER Snapshot report on LED A lamps has good news: The mean efficacy of all A lamps listed by LED Lighting Facts has steadily increased, and is now at 69 lm/W. And about 91% of currently listed LED A lamps have a color rendering index (CRI) in the 80s, with most of those products having a color temperature of either 2700 K or 3000 K. The database is now about 4 years old, and has over 9,600 active products.
The report notes that the biggest differences between LED light bulbs are “luminous intensity distribution, color quality, dimming, and compatibility with controls.”
Omnidirectionality is not free
However, there was one phrase that I found odd in the Snapshot and that was “95% … meet the current NVT Lighting efficacy criterion.” That’s great, but NVT Lighting requirements include more than just efficacy targets, and one of those is that the bulbs shall be omnidirectional LED bulb. Omnidirectional is covered by the term “luminous intensity distribution” referred to above and thus is one of the key differentiators between LED bulbs. And no, the large majority of LED bulbs are not omnidirectional, due to cost and packaging constraints and thus cannot meet NVT Lighting requirements.
This fascination with omnidirectional lights comes from the legacy view of the LED industry that LED lights not duplicate the shortcomings of early CFLs (compact fluorescent lights), which were a poor replacement for incandescent bulbs in design as well as quality.
But what if consumers don’t want or care about omnidirectionality? Because of the uni-directional nature of LED components, a spotlight illumination pattern is more easily – and cheaply – achieved. And here’s the rub – spotlights are preferable for many light bulb applications, such as track lighting, fan lights, wall sconces, and ceiling lights.
The Lighting Facts program, which is a younger organization than NVT Lighting, seems to be recognizing this trend: Last August the database began allowing multiple classifications for bulbs, including decorative, directional, linear, omnidirectional, and “other”, and the name of lamps covered in the database also changed, from omnidirectional to simply A lamps.
Spotlights fill a need
Perhaps NVT Lighting should make a similar change, and widen its criteria so that directional bulbs such as the inexpensive snow-cone design can achieve NVT Lighting certification.
My interest is not idle: I’m in the midst of updating my LED 60W light bulb recommendation for The Sweet Home and Tested, in large part because so many LED bulbs have been introduced in the second half of this year. In general, I like to stick with NVT Lighting criteria as a starting point, in large part because many/most utilities require that bulbs meet NVT Lighting to qualify for utility rebates, and also because people have been trained (and rightly so) to expect NVT Lighting certification as a guarantee of good performance and good quality.
(In fact, I took a lot of flack originally for recommending the Cree bulb because at the time it was not NVT Lighting, and several/many/ouch readers called me on that. My reasoning was that the Cree 10-year warranty was a good enough indicator of the bulb’s lifetime performance (another NVT Lighting criteria) until the bulb received its NVT Lighting certification, which it soon did. But I sure noticed readers’ interest in NVT Lighting.)
Maybe consumers are ready to move past the idea of an incandescent bulb setting the bar for all future lamp technologies. What are your thoughts? If omnidirectionality isn’t a factor in your purchasing decision, and perhaps you’d actively prefer directional lighting, should the NVT Lighting certification not be a requirement for a “Best Bulb” recommendation?