Falling Down the LED Rabbit Hole

Those who’ve followed this blog for awhile know that as a lighting designer I have very mixed feelings about LED as a light source. The technology is ever-evolving, and as such, I think it’s important to keep up not just the technological evolution, but some of the issues of perception.

Which brings me to this article passed along via twitter from greenbuildings.com a key quote:

It is imperative for society to move to solid-state lighting to save money in the built environment and lessen the impacts to the broader environment — but in the U.S. it may take a policy change to force the nation to use more sustainable lighting…

First, let’s bust a myth, it goes something like this, ” LED is WAY more efficient than anything else out there.” Not true. A quick look at Cree’s website and their 4″ LED downlight claims a state of 540 delivered lumens, at 10.5 watts. A 13 watt CFL lamp from Philips delivers over 900 intial lumens. That means for only 2.5 more watts 40% more light is generated by the source.

Now, I know what you’re saying..”but, LED’s will last forever! I’ll never replace a light bulb again!” OK, let’s go back to the same cut sheets. The Cree LF 4 is designed to last “over 50,000 hours” very impressive indeed. The 13 watt Philips-a scant 13,000 hours. So LED wins hands down right? Well maybe. CFL manufacturers have the luxury of a large product line-lamps of multiple bases and types with a lineage. Replacing a CFL lamp is inexpensive, recyclable, and perfectly safe (I know mercury frightens me too, but the amount of mercury in a single CFL lamp is comparable to maybe eating a whole bunch of sushi, I don’t know, but I’d love comments) replacing an LED source…well its hit and miss. Some manufacturers have created modules that make LED replacement simple, others have not. While 50,000 hours is a long time, it’s not forever and when it comes time to swap out LED’s it’ll be very disappointing to find out you have to rip and entire fixture out of the ceiling instead of changing a light bulb. Then there is an even more pressing issue…color.

You’ve heard me harp on it before. Color consistency in LED technology is still not where is needs to be for many applications. While I can open 50 boxes of CFL lamps and know that I’m going to get the same rated color. With LEDs color varies from two of the SAME product, let alone multiple LED sources from different manufacturers.

I’m working on a project right now, that I am unfortunately not allowed to photograph. We are using a linear LED product to light the treads of 4 flights of glass stairs. Every tread is a variation on the rated color, some are yellow, some are pinkish, some are white. And that is one product from one manufacturer (of strong reputation, these things weren’t cheap.

If the technology is that inconsistent when the products are manufactured at the same time. What happens when I’m replacing the LEDs in my ceiling 5-7 years from now?

Lastly, there’s the issue of cost. If we are to become more sustainable as an industry we must throw up as few barriers to sustainable consumer choice as possible. CFL is still the cheapest solution to energy efficient lighting and in this economy, that remains a major selling point.

Now none of this is to throw cold water on LEDs. As I have noted in previous posts they are emerging as a the future of lighting in the electrified world. However, it’s not yet time for the government to force LEDs into the marketplace. Energy codes can surely get stricter and should. But I would like to see LEDs grow into maturity before we see them enter the market place widely. Remember screw-in compact fluorescent was rushed to market before it was ready. What happened? Consumers got lousy color and funny shaped light bulbs and we soured on the product for years. We can’t let that happen to LEDs, in two years, I’m sure I’ll be extolling the greatness of this technology, and in limited application I’m ready to specify, but let’s give this pizza a little more time in the oven before everyone eats a slice.