DOE Solid State Workshop 2022

Earlier this month, I spent a lot of hours in front of the computer listening to the virtual, U.S. Department of Energy, Solid State Workshop. This was four days of in-depth conversation covering the current-state and likely, future direction that solid state lighting technology will take. There was a ton of information shared and honestly, I felt somewhat like comedian George Gobel in the classic Tonight Show episode where he walked onto a dais with Bob Hope, Dean Martin and host, Johnny Carson. Clearly outclassed, Gobel quietly commented to Carson, “Did you even get the feeling that the world was a tuxedo and you were a pair of brown shoes?”

Like Gobel that night, a lot of the information was over my head. These highly educated individuals reached beyond common knowledge and current circumstances. The introduction of LED into the lighting world has elevated the conversations and concepts to heights heretofore unimaginable. Even for a lighting geek like me, it is hard to keep up!!

With that in mind, I’ve tried to boil down the information to that which concerns residential users, or might be of interest to “average” brown shoe-wearing folks.

• No surprise, but LED efficiency continues to improve and gains in efficacy are likely well into the future. LED energy efficiency will however, be less important because of the tiny incremental growth the technology now experiences.
• The use of smarter, better, more carefully programed controls will continue to earn larger and larger shares of the energy savings. The possibility of less expensive electricity (don’t add the money to your bank account, just yet) will change a lot in the way we consider operational value and energy investments.
• In customer preference studies, 5000K lighting was considered the most favorable light in parking garages to find cars and find a parking space.
• The same study showed that the old adage, “We cannot light our way to seeing better or feeling safer.” remains true. At a certain point, regardless of how much light is added, the perceptions of safety and our ability to see in the space do not improve.
• The biggest barrier to altering state and local lighting ordinances for better efficiency, is public perception – people still believe MORE light is the best light.
• As we learn more and more about the body’s need for light, some key metrics will be set on their ear. Initially, daylight harvesting was set in place to save electric lighting energy, but the byproduct may be a healthier environment. That healthier setting could result in higher rents garnered by the owner.
• Additional study are showing that melatonin suppression has a more complex manor of functioning. The wavelength of melatonin sensitivity is different from the visual wavelength. That means, most, NOT ALL, of the impact comes from ipRGC (intrinsically photosensitive retinal ganglion cell) with the cones primarily responsible for short, initial reaction. As science gets closer and closer to understanding this complex interplay, expect lighting to be adjusted with the idea that good lighting can mean good health. This will be a powerful step in the maturation of solid state lighting! (I wrote about this point in a previous post, if interested in more information: https://wordpress.com/post/lightingbyjeffrey.com/483
• Because of this newer understanding of melatonin wavelength peak, we now know that it overlaps with the blue LED that is the basis for most white light. There is now talk of changing blue to violet and then adjusting the phosphor blend resulting in the same visual appearance, but without the harmful byproduct. While not mentioned in this talk, there had been some concern that violet would reintroduce ultraviolet light, losing one of the key benefits of LED light. As with so much of these findings, more information is yet to come!
• Remember the “L” prize light bulbs? The first 60-watt, incandescent LED retrofits announced in 2011? Those lamps are still energized and operating in the test lab! They are all operational, now at 90,000 hours with NO failures and virtually no reduction in light output and color shift! (Remember what I said in the previous post on “buying cheap? https://wordpress.com/post/lightingbyjeffrey.com/603 )
• Many parts of a building are moving to a more sustainable version, but lighting is lagging behind. (Sound familiar? Remember the halcyon days of residential energy use improvements, pre-LED?) It is expected that lighting too, will be dragged into this desire for a more sustainable product. There are reasons why it is more difficult, but in the long run, change will be demanded.
• Diffuser science is getting VERY interesting. Because of the adverse initial reaction to the intense LED “dots” of light, a substantially different diffuser is needed. Diffusers are not just pieces of plastic any longer! Waveguides push light in complex directions to eliminate the glare. Micro-printing adds microscopic dot of wave scattering ink onto the surface, without much light loss or color characteristics reductions.
• Customers are now faced with a much more complex lighting systems. Because everyone want to “invent” the next, best, great luminaire, product has arrived in a silo and the backlash has started. There is growing demand for interchangeability. There is a need for a more common language. In the past, a 40W ballast on a luminaire could easily be swapped. That is not the case with LED. An industry agreement is needed to achieve cross-vendor flexibility. The customer is rumbling and this must be solved soon.
• There is growing evidence that communication between the HVAC system and the lighting systems is needed. Both are needed when people are in a space and not needed when empty. Expect more conversations to come on this merger.
• 28% of carbon emissions are from building operations. That includes lighting. If we are able to bring the cost of electricity down through the use of non-fossil fuel creation (still a while, in my estimation!) then the onus will be on carbon emission from buildings, not power plants! Improvements will be needed, fast.
• The large-scale use of LiFi is as close as two to three years away. Because of our cluttered radio wave environment, this will be a welcome relief and a game-changer.

We need to design light for a space, rather than fitting light into a form that has previously existed. Remember, lighting started with a candle, replaced with gas, delivered in a pinpoint shape, like a wick, changed to a filament in a glass enclosure the shape of a flame and now we are stuffing LED componentry into the same flame shaped envelop! As the science matures, lighting used in the future will be very different. The arc of change is very long, but it does indeed bend. Get ready for it!