Category: Interviews + Opinion

Sustainability And Light Emitting Diodes (LEDs)

A recent editorial in LD&A magazine noted that we no longer have to single out “LED” lighting projects because now almost all projects use LEDs. There is no question that LEDs have drastically reduced energy use in both new construction and retrofit projects. So much so that some are arguing if we even really need lighting energy codes anymore.

By Jeff Schwartz, LC, Member Emeritus IES  – JDS1 Consulting

A recent editorial in LD&A magazine noted that we no longer have to single out “LED” lighting projects because now almost all projects use LEDs. There is no question that LEDs have drastically reduced energy use in both new construction and retrofit projects. So much so that some are arguing if we even really need lighting energy codes anymore.

But if we take a look backward, there are lessons to be learned. When fluorescent tubes, screw-in compact fluorescents, and “PL” type lamps came out, we hailed them as wonderful energy-saving technologies. Then we found out that the mercury they contained was ending up in our landfills. It took years, and the investment of significant capitol, before we started recycling fluorescent lighting. In fact, laws were passed, and codes established to make sure fluorescent recycling got done. We got really good at it, recycling almost all the materials.

With the introduction of LEDs, we jumped right into selling and using them without a well thought out plan to deal with end-of-life. When I first started selling LED exit signs in the 1980s, I joked with my customers that these would last so long “we will both be retired before they burn out.” Well, I was right about burning out, but recent studies have shown that older LED exit signs no longer meet the standards for visibility due to depreciated lumen output. If we are to correct this problem, it means that millions (yes millions) of older exit signs should be replaced sometime soon. And our plan for recycling is?? While there are some companies offering to recycle LEDs, I have yet to find any information on how much of the material is actually recycled.

Metals and metalloids such as arsenic, gallium, indium, and the rare-earth elements (REEs) cerium, europium, gadolinium, lanthanum, terbium, and yttrium are important mineral materials used in LED semiconductor technology. Each of these is used in miniscule quantities. Are they actually being recycled, or is it just the plastic and metal? If these end up en masse in our landfills, what impact will they have on our water tables if they leak? What are the potential health risks? Once again, what are we doing to our environment?

Vermont and California have both recently moved to ban most fluorescent tubes and CFLs, in order to push forward with LED replacements. As noted, we have the ability to recycle all those fluorescent tubes, but what do we do ten or more years from now when the LED tubes reach end-of-life? We know how to recycle the glass, but what about the rest of it?

The National Association of Innovative Lighting Distributors (NAILD) recently put out an open letter in which they challenged our industry to think of sustainability in terms of components (like replaceable tubes) instead of whole fixtures that will be thrown away. While that certainly addresses part of the problem, it still leaves us with a technology that is difficult to recycle.

In summary, sustainability has to be cradle to grave, and I fear that just like with fluorescent lighting, we have not thought through all of the long-term implications for LEDs.

Jeff can be reached at –

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Weighing Into The Lighting Innovation Debate

A debate has recently emerged between industry thought leaders about whether or not innovation has significantly slowed in the lighting industry. On one side, during an interview at Light+Building, industry thought-leaders Mark Lien and Randy Reid argue innovation has slowed. On the other side, thought-leader Carrie Meadows argues that innovation hasn’t slowed, but rather needs to be redefined, in a recent opinion piece published in LEDs Magazine. David weighs in to the debate in today’s LightNOW post.

A debate has recently emerged between industry thought leaders, about whether or not innovation has significantly slowed in the lighting industry. On one side, industry thought-leaders Mark Lien and Randy Reid argue innovation has slowed in this video interview during Light+Building. On the other side, thought-leader Carrie Meadows at LEDs Magazine argues that innovation hasn’t slowed, but rather needs to be redefined, in her opinion piece, here.

Image courtesy

I strongly agree with Ms. Meadows. Massive LED chip performance gains have ended, so innovation has simply changed directions…….in many directions. Rather than repeat Ms. Meadows arguments, here are some examples of how innovation has shifted from chip performance to lamp and luminaire performance, form factors, and convergence features:

Which side of this debate do you fall on? Have I neglected to list other important lighting innovation directions? Comment below.

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Evluma CEO Interview: Streetlight Glare Whitepaper, The New RP-8, & Warming CCTs

David recently had the pleasure of interviewing Don Vendetti, CEO of Evluma. The street and area lighting company has just published a new whitepaper about glare. We also discussed the new ANSI/IES RP-8 standard, as well as the trend toward warming CCTs for streetlights.

I recently had the pleasure of interviewing Don Vendetti, CEO of Evluma. The street and area lighting company has just published a new whitepaper about glare. We also discussed the new ANSI/IES RP-8 standard, as well as the trend toward warming CCTs for streetlights.

Shiller: First, thank you, Don, for agreeing to do this interview. I’ve read the new Evluma whitepaper about Streetlight Glare. It does a great job breaking down discomfort glare versus disability glare, and many of the implications of both types. A big takeaway from this whitepaper is that a well-designed, secondary diffuser / lens can reduce both types of glare. Do a significant percentage of Evluma ROADMAX streetlight customers install the Evluma secondary diffuser optic to reduce glare? Do many install the optional light trespass shields (front-side & house-side)?

Vendetti: David, I appreciate the opportunity to discuss the concept of glare and our ROADMAX product.  Before diving into that, I’d like to give some background on Evluma.  We’ve been around for about 14 years now as a lighting company, and our founders have decades of LED design experience.

With all of our products, minimizing any possible negative user experience in the switch from HPS or MH to LED has been a key focus. There are several key differences between the technologies that can create this negative experience.  These include generally higher CCTs, discrete pixelated light sources, and a high potential for glare due to the use of primary optics.

Our main product until now has been our AREAMAX security light and it is a top competitor, particularly in the rural cooperative electric utilities.  Its design includes a diffused glass lens over a single primary optic and LED source.  This reduces the intensity of the emitted light, especially at higher angles.  While the effect helps to reduce glare, our original intention was to make luminaires that put out a “pleasing light.”

This has been a product design theme for us, including our OMNIMAX retrofit.  Our design of the ROADMAX streetlight is implemented in a similar way as AREAMAX specifically targeting glare, while also making the diffused secondary lens optional and installable at the factory, or in the field.  We did this to allow customers to decide which version is most acceptable in their roadway application. 

To date, there has been strong interest in the diffused lens and many of our sales have included it installed from the factory.  We also have a few customers who selected to install the lens in the field during trials to compare the difference.  The shields are typically purchased to address specific problem areas where light spill is an issue, so the normal scenario is a much lower quantity of shields purchased versus the luminaires. 

Shiller: In some ways, could Evluma’s globes and acorns be considered as secondary diffuser optics to assist in managing glare, for post top lights? Should specifiers think about new globes and acorns as a potential glare control measure?

Vendetti: That’s a very good observation. The OMNIMAX product has several design features itself to help mitigate glare. The first is a silicon lens over the LEDs.  This protects the LEDs from direct contact and also contains a light texture to create diffusion of the light directly from the LEDs. 

The dimensions of the lamp and location of the LEDs were intended to try to get close to the original size and burn center of the HID lamps being replaced.  This design feature leverages the existing globe and acorn optics to put light where it was intended and is particularly important for prismatic globes.  A retrofit lamp that has LEDs in vertical rows extending beyond the central prismatic elements is not going to deliver light as expected and will also look much different than the original HID inside the globe.

With any post-top retrofit project, a decision needs to be made about what to do about damaged, dirty or tired-looking fixtures.  If they are classic globe or acorn fixtures, they can be easily replaced, creating a clean new look with the retrofit lamp.  Additionally, it presents an opportunity to reduce glare versus the legacy fixture by choosing a diffused replacement.

Some of our add-on globes and acorns come in low-glare material, such as LD Acrylic.  This is a highly transmissive, translucent material that diffuses the light and provides a fixture with a soft, low-glare glow.  We have some nice photos in the Gallery section of our website to illustrate some installations. 

Shiller: Do you find Evluma’s streetlight customers to be knowledgeable about glare types and mitigation strategies? Do you see knowledge differences between municipal, utility, and other commercial streetlight customers regarding glare? 

Vendetti: We see a large spectrum of customers with vastly different levels of understanding of glare.  There are some who rely on outside resources or the luminaire vendors to help them understand it.  I suspect understanding glare is an issue in the industry as a whole, not just for our customers. 

The topic of glare is complicated and confusing due to there being multiple types of glare: Discomfort and Disability. Most complaints about glare come from the Discomfort side, typically associated with light trespass. It’s easy to grasp that a light is shining where it’s not useful and is annoying due to being overly bright.  The light is also typically static and at a fixed location, so it is easy to identify when the glare occurs.  However, there is no standard method for measuring it or predicting it with simulation software, so you’re stuck with addressing it when and where it happens. 

Disability Glare is much less intuitive and occurs in the dynamic environment of driving (as can Discomfort Glare). While it has a metric and can be predicted and assessed using simulation software, it is difficult to measure. It can also be impacted by changing conditions, such as weather, and is highly influenced by the age of the driver.  

From my own research, I have had to try to piece together a picture of glare from available publications.  Most of this information is fairly technical and quickly dives into the physiology of our eyes, light adaptation levels, contrast ratios and complicated diagrams using trigonometry.  This rarely helps those looking for a quick understanding of Glare or the causes and solutions.

For these reasons, we feel that we need to be a steward in facilitating a better understanding of glare and how to control it.  This was the main driver in the creation of our new whitepaper on glare as a step in simplifying the conversation for our customers. 

Shiller: Evluma’s website references utilities more than municipalities or commercial end users. Is Evluma primarily focused on the utility streetlight market? 

Vendetti: We have historically focused on the utility market for our AREAMAX product, so this is where our most experience is, to date.  Our OMNIMAX product appeals to many municipal and commercial customers, due to preserving the investment in often high-priced or difficult to replace decorative fixtures.  We expect ROADMAX to have appeal across all segments, including DOTs. 

Shiller: The IES recently released their updated ANSI/IES RP-8-21 Recommended Practice for Lighting Roadway and Parking Facilities. Do you see this updated roadway standard impacting the market and Evluma’s business in any way?

Vendetti: Our experience with RP-8 started in 2016 when we introduced a Type III distribution on AREAMAX, and some of our customers wanted to use it as a streetlight. It was then that we got a crash course in understanding the tools and calculations, and how well our product performed against the recommendations.  We used these learnings to focus our efforts on our ROADMAX design a few years down the road, and the 2018 version of RP-8 became a major influencer for us.

The 2018 version was a massive unification of several individual IES docs into a more comprehensive discussion.  I would call the 2021 release more of an incremental improvement that helped to update and clarify multiple sections, in addition to adding a few more sections that augment roadway recommendations, such as pedestrian lighting.

What we’ve seen in reviews of existing older specifications within utilities or municipalities is that many of them include only partial specification of the RP-8 recommendations.  These typically include the average illuminance ratio and the average-to-min uniformity ratio, and some expand to the max-min uniformity value. There is a strong focus on uniformity ratios, and missing in many of the specs is the veiling luminance ratio recommendation.  This may be due to the discussion of Glare being essentially an appendix in the RP-8-2014 version, and thus veiling luminance was not a strong area of focus. It also required shifting the thought process from illuminance to luminance, a more difficult concept to grasp and to measure in the field. 

In the 2018 version, Glare got its own major section and thus marks a shift in focus.  There is also the insistence that all four of the recommended RP-8 parameters, including veiling luminance ratio, should be specified.  This helps elevate the importance of paying attention to Disability glare for any new or updated specifications for a new deployment. 

This will certainly have a positive impact on the market as a whole and for Evluma.  We have attempted to provide a product that achieves strong performance for roadway lighting while also meeting all the recommended metrics, with a major focus on minimizing Disability Glare (aka veiling luminance). 

Shiller: There is a quick reference in the white paper to the trend of decreasing CCTs for both human and wildlife health. I see Evluma luminaires and retrofit lamps go down to 2700K CCT. Does Evluma have any opinions on streetlight products beginning to be offered in 1800K, 2200K, and 2500K CCTs? Can you share if Evluma has any plans to offer any CCTs below 2700K?

Vendetti: Our current OMNIMAX post-top product already offers CCTs as low as 2000k and 2200k, so we have been a supporter of low CCTs. We do expect the trend for lower CCTs to occur in streetlights over time as more municipalities weigh the trade-offs and feedback from the communities. 

There is still a relatively large efficacy loss at 2700K versus 4000K and it increases significantly as you go lower.  For example, moving from 2700K to 2200K has an efficacy drop of 20% or more.  This could require going up in luminaire power proportionately to achieve the recommended lighting levels in RP-8, so this needs to be considered.

As far as Evluma plans, our priority is getting our full portfolio of ROADMAX versions to support 250 and 400W HPS replacements later this year and then we’ll shift to focus on additional options, such as lower CCTs.

Shiller: Thank you very much, Don, for sharing your expertise with our readers.

The Evluma glare whitepaper can be downloaded for free, here. Evluma will also be exhibiting at the upcoming IES Street and Area Lighting Conference, October 10-13, in Dallas, Texas. Their booth number is 306.


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Interview With NexGen Power Systems’ CEO About Their Game-Changing Driver Technology

David had the pleasure of interviewing the CEO & co-Founder of NexGen Power Systems, Dr. Dinesh Ramanathan, about NexGen’s ground-breaking, power system technology, and their higher-performance LED drivers.

I had the pleasure of interviewing the CEO & co-Founder of NexGen Power Systems, Dr. Dinesh Ramanathan, about NexGen’s ground-breaking power system technology and their higher-performance LED drivers.

Shiller: First, I want to thank you for agreeing to speak with me, today. Maybe a good place to start is a brief description of NexGen Power Systems.

Ramanathan: Sure. NexGen Power Systems is a vertically integrated company that makes power systems which are very efficient, very small, very lightweight, and very environmentally friendly. The way we do this is we have three technology cornerstones on which we have built our technology. And these three technologies have been put together to allow us to make a power platform. That power platform is then applied to each one of the verticals that we end up serving. From a power systems perspective, the three key properties of what we do are our transistor, which is GaN on GaN, vertical gallium nitride power transistor. The second is our Merlin Power Engine, which basically has software and algorithms which allow the power supply and power system to work at one megahertz plus switching frequency. And the third is innovations that we have done on mechanical and thermal designs, which allow us to operate these power systems at the thermal boundary, which means we make them as small as we potentially can, and still make sure that they don’t get too hot.

Shiller: How was the technology received at LightFair? Did the lighting industry react to your value proposition, and do you think it understood your value proposition?

Ramanathan: They did, and this was our first time at LightFair, so we had a few things to learn, ourselves. But the overarching theme that we encountered was that everybody that is making LED lighting fixtures is looking for their drivers to become smaller, more efficient, and more lightweight. So that kind of fell directly in with our value proposition. That’s what we do. Now, they are not as savvy about the technology that goes into making the systems smaller, more efficient, and lighter weight. But what they care about is the outcome, which is making sure that the LED drivers that we put out into the marketplace are smaller, more efficient, and lighter weight.

Shiller: So a great black box is good enough for them.

Ramanathan: Yes. And that was the learning for us, because we were trying to explain how the technology works internally. What makes it smaller. And I don’t think that they care that much about the details of what goes in. What they care about is what they’re getting out from it, which is perfect because we can provide the solution that the customer wants without complicating their lives too much.

Shiller: The most striking thing I remember from our conversation at LightFair was that your vertical GaN transistors create drivers that are 6% more efficient, enabling a 250% increase in lumen output within the same size luminaire or smaller. And that’s a remarkable increase in light output. And I’d like to unpack that a little bit. Can you explain how your vertical GaN transistors create higher frequency switching and the 6% higher efficiency while also being smaller? I mean, it’s a lot going on.

Ramanathan: Let’s take them one step at a time. So fundamentally, from a 10,000 foot view, what tends to typically happen when you run power systems at higher switching frequencies is you shrink the size of all the passive elements that are there in a power supply. The passive elements are inductors, capacitors, transformers, all these basic elements become smaller. They become smaller because the total amount of energy that is now being transferred from the primary side to the secondary side in a circuit has become smaller with the higher switching frequency.

Shiller: The area under each curve, if you will?

Ramanathan: Yes, the area under each switching cycle is much smaller. You only need small amounts of inductors and capacitors to transfer energy from the primary to the secondary. So you don’t need as much local storage as you previously did, when there was more energy per cycle. Another very important thing that also happens is the filter that you need for conductive electromagnetic emissions becomes smaller. Why? Again, for the same reason, there’s only a small amount of energy that you’re transmitting per cycle. That’s the energy that you have to filter for any noise that gets injected into the AC line. For radiated emissions, we have a little heat spreader that we put around the system to make sure that the heat is uniformly distributed, that also acts as our EMI shield. So using that feature, we are able to make the entire system much smaller and also be able to bypass all of the constraints that are typically imposed on systems like this.

Shiller: That’s a great explanation with the frequency. But the next level up where the 6% improvement in driver efficiency enables a 250% improvement in light output. Is there a way to break that down? How much of that’s due to reduced heat versus reduced size?

Ramanathan: Right. So the way to think about how we’re able to produce more light is actually to do an apples-to-apples comparison. So it’s all about size. If you take a look at how small we can make the LED driver and then you look at how much power is actually generated by any other LED driver in that same form factor. Because we are able to reduce the size by roughly 60%, we can actually produce in that smaller form factor the same amount of energy by something that’s two times as big.

Let’s take an example. So let’s say our driver had a volume of two cubic inches. If we were able to put out, let’s say, ten watts of power. The competition is using four cubic inches to put out the same ten watts of power. So in four cubic inches, we could actually put out twice the amount of light or twice the amount of power.

Shiller: So because you’ve halved the volume, you’ve essentially doubled the power density, and halved the thermal density.

Ramanathan: Exactly right. So the 6% improvement in efficiency has to be there, because otherwise we can’t shrink the size by 50%. And the way to think about a 6% increase in efficiency is to look at the losses and look at the fact that we’re actually cutting the losses down by roughly 50%.

Shiller: That occurred to me. So you’re going from roughly 15% losses to say 8 or 9%, maybe?

Ramanathan: Yes. We’re cutting 15 point worth of loss to roughly 8 or 9 points of loss.

Shiller:  Which is roughly a 40% reduction in losses?

Ramanathan: It’s more than 40% of the overall loss that’s actually eliminated.

So these two mechanisms, reduced heat and reduced size, put together is what allows us to generate a lot more light in the same form factor. And I think the key issue is to look at the form factor.

I’ll give you another example from the data center applications that we’re working in, where our power supply size is fixed. Because we can provide more power density, we can actually give twice the amount of power in the same form factor. And if you’re able to give twice the amount of power in the same form factor that our customers are looking for, then they can deploy more server racks. The same thing happens in the LED lighting space.

Shiller:  So, it’s hard to separate the reduced heat and size because one enables the other and then they compound. Can you elaborate a little bit on the high frequency transistors reducing EMI. Can you talk a little bit more about the consequences, how it eliminates a lot of components?

Ramanathan: So this is a two-step process. First, because of the technology we’re bringing to the table, we’re actually able to shrink the size of all the components. The actual number of components isn’t shrinking. They’re actually becoming slightly larger. And the reason for them becoming slightly larger is because we have an external gate driver outside the Merlin Power Engine, which is what we use to drive our gallium nitride transistor. Most of the controllers that you will see in the marketplace, especially in the LED space, they have integrated all these drivers into one chip because they have made these ASICs. We haven’t because it’s new technology. So, the next step in our program is to take some of these circuits that we have had to put outside and actually build it into ASICs. And when we do that, that reduces the number of components that we have outside. It will also allow us to make sure that the design is much more cost efficient than it is today. It’s already cost efficient primarily because it shrank the size of all these components. But now we’re actually able to integrate some of those external components into our controllers. And then that causes the next wave of cost reductions that we can bring to the table.

Shiller: At LightFair, you shared that the company recently emerged from stealth mode and that you were pursuing lighting, automotive and computer hardware industries. Is that an accurate statement?

Ramanathan: That’s correct. So we’re pursuing LED drivers. We’re looking at power supplies for high end laptops, for data centers, and for electric vehicles. So you’re exactly right.

Shiller: Circling back to the ASIC conversation. When you develop ASIC drivers, do you see them being small enough for use within lamps, or what most people call bulbs, because that’s how they can get drivers into a screw shell, for example?

Ramanathan: We fundamentally believe that they will become much, much smaller than they are right now. And we do that by integrating everything that’s outside into an ASIC. There are a lot of components that we have outside, primarily voltage adjusters and things along these lines which don’t need to be outside a chip at all. They should actually be inside a chip. The semiconductor industry makes ASICs that are specific for lighting applications. That’s what we intend to do with our control engine. Now, all those engines typically run between 60 and 100 kilohertz. Our ASICs will basically be operating these switches at a megahertz-plus switching frequency. That’s the next way for us to bring costs down and also shrink the size. The other thing to also point out is that one megahertz is where we are starting today. From one megahertz, we can go to 1.25, 1.5, 1.75. 2. And at each one of these levels, the components that we talk about shrink in size. So that’s an advantage that we bring to the table.

Shiller: So that’s a peek at your roadmap, right?

Ramanathan: Yes, we just keep going. To some extent, we have to wait for some other components to catch up to our increasing switching frequency. So, for instance, the magnetics have to catch up with where we are. So if you’d asked the same question about four years ago, most magnetics would have worked at about one megahertz switching frequency or they would have been characterized up to one megahertz. Today, when you go look at magnetic material, the magnetic suppliers are characterizing them at two and even three megahertz switching. So, we know that as we push the switching frequency further and further up, the magnetics guys are doing their part in making sure that the ecosystem is actually a place where these technologies can come to bear.

Shiller: Can you share a little about which aspects of your manufacturing are occurring in India versus the US?

Ramanathan: Sure. So the way we run our organization is that our transistors, which is the key portion of our technology happens in the United States. Our fab is located in upstate New York. It’s in Syracuse. And it’s a big fab that does both manufacturing, as well as R&D. For us, that key technology that we develop is based in the United States. The rest of the system development front, we do between India and the US. We have a group here in Santa Clara and another group in Southern California. They do most of the prototyping work of some of these really high frequency, advanced designs. And then those designs are taken over by our team in India, that takes and replicates them on various levels. The team in India actually does mechanical design. They also do some of the software work. They do all the EMI work and the full system validation gets done in India. The contract manufacturer that actually builds these systems for us is also based out of India. We took into account some of the geopolitical issues that we’re seeing in the world today.

Shiller: That’s where I was headed next. At LightFair, you referenced an enormous increase in Indian manufacturing that’s occurring with global exports. Would you like to speak to that at all? And whether you see India challenging Chinese dominance in global manufacturing.

Ramanathan: Yes, I think India will, at least based on what we are hearing from our contract manufacturers and others, in India. Their output has gone up significantly. And I’m not telling you anything that is hidden or not known. There have been articles that say that iPhone 13 manufacturing is actually happening in India and it’s being done by Foxconn and other players that do work for Apple. I would consider iPhone 13 one of the most complicated pieces of electronic hardware that gets put together. And if that’s getting done in India at volume, you can understand the sophistication that’s actually at play at this point in time. Our contract manufacturer is increasing their capacity by about 5X, and the reason they’re able to increase it and they’re going 5X is just to make sure that they have the capacity to look at a lot of contract manufacturing that is moving away from China and into India. And an interesting part is, our contract manufacturing, for instance, is actually largely owned by a Chinese company. And the conversations with those contract manufacturers tell us that as long as we’re able to get contract manufacturing done in whichever country that makes sense for us, they’ll continue making it in those countries. I think some of the business folks inside China have also realized that having shutdowns and stoppages of manufacturing doesn’t help them. It doesn’t make their customers any happier. So they’re thinking “how do we make sure that our supply chain is as robust as we can?” And that means setting something up outside of China makes perfect sense.

Shiller: The pandemic issues are just one challenge with the Chinese supply chain. There are other geopolitical obstacles growing.

Ramanathan: Yes.

Shiller: What can you share about your commercialization timeline?

Ramanathan: Our full commercialization is going to happen in the fourth quarter of this year, towards the end of this year. And that could possibly slip by a month or so. So I’d say towards the end of this year or very early part of next year is when all our products will actually go into the market. The LED products are a little further advanced compared to the rest of the products, but it’s no more than a month or two. So we expect to start shipping in volume towards the end of this year.

Shiller: Very good. Do you plan to sell your drivers through electronic distributors like Arrow, Mouser or Future? Or through an internal OEM sales organization that you’ll have to build?

Ramanathan: Initially it’ll be an OEM sales organization and most of what we’ve been doing from our marketing and sales approach is a very targeted digital marketing campaign, that we’ve been putting together and that targets very specific customers and very specific engineering organizations, inside those customers. So we expect to end up working with the top 10 to 15 customers in this particular space because we are trying to work our way from top down. Once we get those customers lined up and show them the technology that we’re bringing to the table, then it’s a matter of how to scale that? This becomes when Mouser and all the other distributors kick in.

Shiller: I see all of the benefits for a luminaire maker, but I see even more profound benefits to lamp makers because they are just so much more space constrained and thermally constrained. Can you speak at all to a roadmap or a timeline to benefiting lamp makers as opposed to luminaire makers?

Ramanathan: Yes, so lamp makers are a little trickier, and the reason they are trickier is primarily because cost is one of the primary requirements that they have. So we get to that lamp market once our technology starts to ship in some volumes.

We could even think of taking our our gallium nitride chip and actually making and integrating it into the package that we put together so we can have an ASIC with our gallium nitride all on the same chip. That then gives them the smallest form factor, but that’s at least two years down the road for us. It’ll take roughly 18 months to put our basic product out into the marketplace. Pursuing the lamp market is going to be a function of how small we can make it, and how effective it is for them.

Shiller: Thank you, Dr. Ramanathan, for sharing your exciting technology with our readers.

Download the NexGen whitepaper Miniaturization of LED Drivers with NexGen Vertical GaN Technology here.


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So You’re a Fixture Chooser? A Guest Authors’ Perspective

Guest authors Clifton Stanley Lemon & Thomas Paterson make the case for eliminating the term “specifier.”

By Clifton Stanley Lemon and Thomas Paterson

Exactly when did lighting designers consent to allow themselves to be referred to as “specifiers,” the ones who pick the lighting equipment? Other trades and disciplines don’t suffer this indignity: we don’t call artists “paint choosers,” interior designers “furniture pickers,” or mechanical engineers “pump, fan, and duct table monkeys.” “Specifier” indicates an inordinate attachment to equipment and technology, not to the more important process of why you need it in the first place, an essential human activity known as “design.” Let’s just refer to all lighting designers by what they actually do. The profession will be better off for it.

We have been having conversations that touch on this topic as preparation for the LightSPEC West conference in Los Angeles on September 21 and 22, at which Thomas is keynoting with a talk entitled “Craft and the Creativity Myth.” Here we introduce some of our discourse and discuss the terms that come into play when explaining and defining the practice of lighting design.

One meaning of the term “specifier” from is “someone who draws up specifications giving details (as for obtaining a patent).” This harks back to the early days of electricity when the bloodthirsty, contentious, competitive process of patenting and commercializing inventions by people like Edison, Tesla, and Westinghouse had decisive outcomes on the future of technology. In fact, it is a way of addressing light though it is simply a matter of appropriately sizing grids of troffers.

Let’s abandon “specifier” in favor of “lighting designer.”

Let’s talk about what we are, starting with what we aren’t. With all due respect to hallowed and heartfelt organizational mission statements, lighting design is, strictly speaking, neither art nor science. We’re not artists, strictly speaking. We design to a brief (should we be fortunate enough to get one) to solve our clients’ needs. That’s design or engineering, not art: we celebrate great art, but creating it isn’t what we do. Art is typically neither driven by external purpose nor regulated by the government.

Lighting design is also not science. We use the results of other people’s scientific learning. But as a lighting designer, when did you last do a double-blind study to inform your design? Or discover a new principle of physics? Or publish a peer-reviewed paper? When did you formulate a hypothesis, prove or disprove it, and submit that new knowledge to the review of your peers? We use evidence in making important design decisions, but that doesn’t make us scientists.

According to legendary designer and architect, Charles Eames, design is “a plan for arranging elements to accomplish a particular purpose.” The key ideas here are “plan” and “purpose.” Much of what people do when they design may indeed involve planning – although that’s often omitted in the rush to decorate – but typically fails because the necessary purpose is poorly defined, if it is defined at all. Design as a term ties many things together. It’s a fundamental human activity. “Designer” as a professional descriptor is well understood across many fields, from graphic design to industrial design.

Lighting designers are creative, but do we have creativity? Does creativity really exist? Or is it just a bullshit term that belies a fundamental misunderstanding of design practice and discipline?

We suggest that the creative process is generally misunderstood, confused with butterflies of inspiration, overrated, and carries a corrosive connotation of inherited merit vs. learned skill.

So then, what is it that lighting designers do? We believe that what designers practice is craft, the professional craft of design.

What defines craft? You’re probably thinking of activities like woodworking, decoupage, and making things with popsicle sticks and pipe cleaners, a la Hobby Lobby – unthinkably lowbrow vs. intellectual and professional. For instance, several years ago, the California College of Arts and Crafts (which Clifton attended) became simply the California College of the Arts. Their curricula span architecture, film, fashion, ceramics, comics, furniture, and game arts (and presumably not decoupage).

Craft is formed of a broad knowledge of the media with which one works, the way it will be used, its acquisition, and application. A great craftsman responds to a client’s needs to create something that serves their purpose with grace, elegance, economy, and often great beauty.  What better description of the craft of lighting design?

Making craft implicit in design practice invites a bold realignment of entrenched hierarchical social values. The Old English word craeft signified an indefinable sense of knowledge, wisdom, and resourcefulness. Today, it implies a deep holistic internalization of all the design skills necessary to deliver successful projects: research; defining purpose, problems, and intent; visualization; communication; collaboration; technical understanding; hands-on testing and verification; sourcing; budget management; problem-solving; construction management; and post-occupancy assessment.

Thinking of lighting design as a craft enables a more accurate understanding of necessary skills to be assembled in the mind of a craftsperson in order to form a new mastery. It allows us to look at the professional development of practitioners in our industry as a studied process of building skills and people, rounding out the areas they have not yet learned, and working to bring craft to the collective product of our field.

Recognizing this also allows us to value people at each stage of their career, from apprentice through journeyman/woman to master. Each is a stage of life, with a different focus on personal development, application, and generosity in teaching to the following generation.

Mr. Paterson’s keynote session on Wednesday, September 21, will explore a new perspective on lighting design and the craft needed to practice it. He’ll show how learning in a design practice can be facilitated through mentoring, transparency, continuing education, and direct jobsite experience. His firm Lux Populi, one of the top lighting firms in the world, encourages a culture of active listening, engagement with clients, experience-based problem solving, and collaboration with all other design and construction disciplines. Of course, they choose fixtures, but they’re designers first and foremost.


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John Arthur Wilson Interview: Better Bricks Wireless Lighting Controls Guide

David recently had the pleasure of interviewing John Arthur Wilson, a lighting control and utility rebate consultant, about his 2021 market research into wireless lighting controls. That research resulted in a learning guide that can be used to support basic education around wireless trends in lighting. The Northwest Energy Efficiency Alliance (NEEA) has published that document on their Better Bricks website, available to the public.

I had the pleasure of interviewing John Arthur Wilson, a lighting control and utility rebate consultant, about his 2021 market research into wireless lighting controls. That research resulted in a learning guide that can be used to support basic education around wireless trends in lighting. The Northwest Energy Efficiency Alliance (NEEA) has published that document on their Better Bricks website, available to the public, here

Shiller: The wireless control guide that you created for Better Bricks is a great document about wireless lighting controls. It provides a simple explanation of load control devices, the protocols, frequencies, performance, topologies, proprietary versus open, and more. Who was the primary audience for this guide?

Wilson: The guide was purposefully meant to target a broad audience set, and that was largely because it was something that we wanted to be really accessible. We didn’t want it to go overly in-depth in any one area to where you really needed to have a technical background. The idea was that this is something that could be leveraged either in training settings or to educate end users. So, the idea is that this guide is something that any organization across North America could pick up and could incorporate into any sort of workshop they’re doing. For example, if we’re working with electrical contractors or a utility with a strategic energy management program, and they’re working with facilities people or key decision makers. It was meant to be something that they could incorporate into their curriculum and leverage it.

There was a big body of research that informed why the guide was needed in the first place. Over a period of six months, we worked in-depth with over a dozen lighting control specifiers. We had electrical engineers, we had lighting designers, and we had contractors that design, build, and commission. We asked a lot of questions about project specifics to better understand the lighting control specifier and the customer. One of the things that came up repeatedly, was that luminaire level lighting controls (LLLC) has a massive “value engineering” problem, due to their higher costs. If you’re just looking at first costs upfront, people are saying this costs more, but there are so many other benefits. One of the major benefits is the wireless aspect. It streamlines installation. Some lighting specifiers and their clients are concerned about cybersecurity with wireless controls. We ask, is cybersecurity an issue on your jobs? And for most projects, it’s not. There’s a disconnect between how much we talk about cybersecurity as this generic boogeyman and then how much it’s actually an issue. But 80% of the actual cybersecurity risk isn’t wireless devices in the network system. They pose a tiny risk, but it’s nothing compared to the way your gateway is connected to the Internet and how you have established user access and password protection. That’s where the overwhelming majority of cybersecurity risk is.

As soon as you say no to wireless, you’re negating all the other wireless benefits. Wireless was a pinch point that we identified. In working with these specifiers, we realized there is typically an opportunity to educate the end user. We created the wireless guide to be an educational resource that could be part of that conversation when specifiers are talking to decision-makers.

Shiller: The wireless guide was published last year, right?

Wilson: The very end of last year.

Shiller: What’s been the overall response to the guide. Is NEEA happy with the clicks, downloads, and attention that it’s getting?

Wilson: Yes, I think they’re very happy with it. People love that even though it’s ten pages, it’s not dense. We kept it high level including a lot of graphics.

Shiller: After the basic education aspects of the guide, it dives into three major trends with wireless controls:  data resiliency, automatic device reconnection, and latency versus simultaneity. I was wondering if you wanted to talk a little bit to those three trends?

Wilson: Yes, I think of it as properly addressing past problems. They’re not wrong and they’re not imagining it. They’re right. Resiliency was a real issue. It is important to validate that. Wireless has gone from mostly reliable to resilient. There was an issue with devices that would fall offline, or just wouldn’t connect, and that was an issue. The biggest improvement here is the mesh network. You’re no longer reliant on an individual node, so that if something happens to that node, the message isn’t going to get passed. Another problem is that when people hear wireless, they almost always conflate it in their heads with Wi-Fi, which is just one type of wireless, but it’s not really the type that matters in commercial lighting. In fact, Wi-Fi plays a tiny part in commercial lighting networks, overall.

Shiller: What about automatic device reconnection?

Wilson: This one really matters. It was incredibly common and just so unbelievably frustrating when a device would invariably fall offline and then come back online. Now, these devices can come back online, they know who they are, they know who they’re supposed to be talking to, what they have received in between, because there’s timestamps. Before, people had to open the ceiling and press a button and put it back into discover mode, and then you have to reconnect it to the part of the network it was in, which was just awful. So, that was a major improvement.

Shiller: Great. And the third trend was latency versus simultaneity.

Wilson: Yes. Latency versus uniformity, simultaneity or whatever you want to call it. It drove my lighting designer friends up a wall. When you have a large space, and the scene command would get sent out, you’d get this ‘popcorning’ of lights changing at different times, throughout the space. This problem has been solved with time-synched commands, which is very cool. You can have a mesh network that sends this command out over a space, with a time signature stamp on it. Then when it gets to individual nodes that are controlling that, it sends the synchronized command out to all the rest of the devices so that everything happens uniformly. It is one of the major macro trends that I believe is a big step forward.

Shiller: What do you think are the most important takeaways from the guide, that you’d like specifiers to know? 

Wilson: I think the most important thing in the guide is that every single one of these issues doesn’t matter for every single job. Just focusing on wireless as the cause of cybersecurity risks does nothing to address the actual cybersecurity risks. The most important thing is it’s a tool kit to help specifiers understand the advantages of wireless, to help support a solution that is best for the client.

Shiller: Were there any topics left out of the guide in order to keep it short, manageable, and digestible? I’m curious if there are things you wished you could have fit in, but you couldn’t?

Wilson: We got all the major topics in it. There’s always a risk when you’re an inch deep and a mile wide that you’re not hitting the important details. We could really nerd out on this stuff, but those conversations don’t actually matter for decision-makers. There are always areas that we could have gone deeper on. And one, I wish we could have gone deeper on is open versus not open. The truth is we don’t have anything close to open in lighting, even though 98% of products on the market are based on open but have been tweaked to proprietary. And then the way that these companies talk about their systems being open is very misleading. Similarly, the way that they talk about if you need a gateway or not is very misleading. It’s like you don’t need a gateway for the most basic functionality, but if you want something like scheduling, you’re going to need a gateway. Rather than trying to answer all the issues through this guide, we set the table and then say, don’t be afraid to ask, what is this? How open is it, or is this a totally proprietary solution? Is this the solution in the middle where we still have an open API?

Shiller: John, I really appreciate you sharing your expertise with our readers. Thank you. The NEEA Better Bricks Wireless Lighting Controls Guide can be downloaded here.

edited July 18, 2022


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Interview: The Circular Economy For Lighting

The GreenLight Alliance (GLA) is a non-profit organization with leadership across Europe and North America, dedicated to applying circular economy principles to the lighting industry, targeting specifiers to drive change. I interviewed Emilio Hernandez, Chair of the GreenLight Alliance about the GLA’s goals and strategies.

The GreenLight Alliance (GLA) is a non-profit organization with leadership across Europe and North America, dedicated to applying circular economy principles to the lighting industry, targeting specifiers to drive change. I interviewed Emilio Hernandez, Chair of the GreenLight Alliance about the GLA’s goals and strategies.

Shiller: The Green Light Alliance (GLA) mission seems straightforward, to promote circular economy practices in the lighting industry, especially among specifiers. What actions is GLA taking to make that happen? That’s less clear on the GLA website .

Hernandez: That’s an excellent question. We’re approaching this from several angles. A key aspect is education and awareness. People can follow GLA and receive newsletters and invitations to discussions on circular topics and webinars from industry bodies and manufacturers who are pushing the dialogue on the subject forward.

But our main role is to build a trusted network and facilitate a dialogue between people across the industry.

Shiller: The Information Hub that GLA has built on the website is very interesting. There appear to be 11 documents, standards, and white papers about applying circular economy and sustainability principles to the lighting industry. Is it correct to say that most of these documents appear to be European efforts, rather than North American efforts, to-date? 

Hernandez: This is true, you need to start somewhere and we are relatively new in terms of our existence. We’re trying hard to reach out and have ambassadors in the US and are more than open to other regions, too. We have already found a lot of benefits to opening up the dialogue. To better understand different challenges, we collaborate on initiatives to further our reach, and concentrate the efforts that are happening.

Shiller: Are there any significant North American efforts to apply circular economy principles to the lighting industry, that you’re aware of? 

Hernandez: I’m not aware of any significant lighting focused circular economy initiatives in North America (but happy to be proven wrong!) However, there is a growing requirement for Life Cycle Analysis (LCA’s) and environmental product declarations (EPD’s), in construction. New York’s NYSERDA and California’s Title 24, for example, are bringing in requirements on a state level, and LEED is offering credits for building materials with EPD’s, or materials that use ‘healthy’ materials.

LCA’s are an important way of measuring a business’s efforts to improve the embodied and emitted carbon within a product’s lifetime, hence the LCA incubator that we are partnering on with the IALD Lighting Industry Resource Council (LIRC). This has participating manufacturers from the US who are really interested in developing these principles as part of their business model. StickBulb and Lumenwerx, for example, were very quick to be part of this discussion, and PNNL has also been a helpful partner on the project.

Shiller: As you are based in Sweden, do you see Europe leading this effort, globally?

Hernandez: There are currently financial incentives to migrate over to circular business models in Europe, via subsidies as part of the EU Green Deal, which is the ‘economy’ part of the circular economy. Good intentions will only take this so far, so it needs to be economically viable. We’re aware of manufacturers’ concerns over the uncertainty of costs associated with decoupling from linear business models and producing EPD’s. It can be an expensive process so we’re trying to understand how this can be achieved in lighting quickly, reliably, and affordably.

Shiller: The GLA website has a case study page with 9 case studies listed. Do you have a favorite case study among those nine, that best shows what’s possible in bringing the circular economy to lighting?

Hernandez: The best thing about them is that they all have different insights into approaches to circularity. This migration to circular design isn’t a straight line process. There are legacy products on the market which can be innovatively remanufactured, and there are approaches to new fixture design or specification that will yield benefits at the end of their designed life. However, something we are trying to help people understand is that a low embodied carbon product, that is majority recycled or disposed of at the end of its first life is not really circular, it’s just a lightweight linear economy.

Shiller: If any LightNOW readers find this subject interesting (almost half of LightNOW readers are lighting specifiers), what are some ways that they could get more involved in GLA and its mission (i.e. join GLA, subscribe to GLA, other?)

Hernandez: Please get in touch with us directly if you have a specific need or would like to be a more involved community member at, and subscribe via the website and you’ll receive a newsletter with updates, periodically. Our LinkedIn community is useful for up to date sharing of webinars and articles, and they can all be found here.

Shiller: Thank you for sharing your expertise, Emilio.

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Interview: Korrus’s CEO On The Recent Acquisition Of Circadian ZircLight

Korrus is the company that owns Ecosense, Soraa, Scuva, Tempo Industries, and now Circadian ZircLight. They focus on “Human Light Interaction (HLI),” which they define as seeking to understand human interactions with light, and creating technologies that better serve the needs of those humans.

Korrus is the company that owns Ecosense, Soraa, Scuva, Tempo Industries, and now Circadian ZircLight. They focus on “Human Light Interaction (HLI),” which they define as seeking to understand human interactions with light, and creating technologies that better serve the needs of those humans. I interviewed Mark Reynosa, CEO of Korrus, about their recent acquisition of Circadian ZircLight, and where Korrus is going from here.

Shiller: Congratulations, first off, on the acquisition of Circadian ZircLight.

Reynosa: Thank you so much.

Shiller: I was curious whether the acquisition would impact the partnerships that Circadian ZircLight currently has, providing light engines to partners like Acuity, H.E. Williams, and presumably others? Will the OEM engine play still be a focus for Circadian ZircLight?

Reynosa: Yes. We have no intention to interrupt any preexisting agreements and relationships between ZircLight and other participants in the industry. Quite the opposite. The entire thesis around our acquisition has been it supports our mission and the thesis is about enabling and creating greater awareness around solutions that deal with some of the ill effects of artificial light in the world, today.

Shiller: You mentioned the ill effects of artificial light. Most of the circadian lighting manufacturers leading the space have focused on what I consider a high cyan / low cyan, 2-channel approach. That’s been the dominant approach by multiple players. I’m curious if you envision circadian lighting moving beyond this 2-channel approach, to more sophisticated levels of spectral tuning?

Reynosa: We’ve been working really hard for quite a long time to really understand, at the physiological level, what actually works well in terms of understanding spectral energy. The kind of light that naturally occurs from morning till evening, and then asking ourselves, to what degree can we accurately replicate that spectral energy, to effectively entrain one’s circadian system. Through a tremendous amount of work, and years of research, we believe we have a technology platform that actually delivers on that promise. And you’ll begin to see our dynamic offering in that regard, begin to enter the marketplace next year. We believe it is materially differentiated from anything you’ve seen in the world, heretofore.

Shiller: So you’re saying that there are different approaches coming, beyond this 2-channel, high cyan / low cyan approach? Do you agree that something more sophisticated is coming, without asking you to give it away?

Reynosa: Yes. It’s been a very clear focus of ours. All through the organic work that we’ve done, and then through the acquisition of Soraa, and now with ZircLight, we have almost 500 patents in the intersections of humans and light, many of which have to do with one’s physiology, biology, and how it interacts with one’s circadian system and the natural environment. We don’t believe there is anything in the marketplace today that accurately reflects what occurs in nature. We think what we are building towards is quite likely a step function change from what is available today.

Shiller: Sounds exciting. You mentioned the Soraa asset acquisition in 2020. There was also the Lumium acquisition in 2019, the Tempo Industries acquisition earlier this year, and now Circadian ZircLight. Do you foresee Korrus acquisitions continuing at this pace?

Reynosa: We don’t really have a time-based acquisition strategy. Our business model and strategy have been pretty clear for the better part of almost a decade now. Sometimes there are opportunities that allow us to scale our vision more quickly. And in those instances, if we see that opportunity, we will take advantage of that through an acquisition. Otherwise, like Scuva, we’ll just build it internally. In fact, you’ll see an announcement coming shortly from us whereby we are partnering in the marketplace with an entity to help us increase the speed with which certain life-based technologies can be delivered to the marketplace, to increase human health and well-being, literally. You’ll see that announced in a number of days or weeks.

We build it internally, we acquire something externally, or we partner with someone. We’re very agnostic about the pathway through which we execute. The key for us is that we see it as a tremendous opportunity to get critical technology out to hundreds of millions, if not billions of people. We just focus on the ways in which we think we can do that best.

Shiller: The Lumium Lighting brand was turned into a product line under Ecosense, but Soraa and Tempo remained separate brands. Will Circadian ZircLight remain a separate brand or be consolidated like Lumium?

Reynosa: The distinctions between how we operate a particular brand varies depending on where we think the best way to maximize against our vision is. We haven’t completely determined the right way to optimize the ZircLight platform, because it is a just announced acquisition. Part of what we do is go out to the existing marketplace partners and ask them how do they feel we can best support them in their efforts with our technologies and solutions. We take that input into account in how we think about an execution perspective.

Shiller: With this Circadian ZircLight acquisition, Korrus is very well positioned and represented in the circadian and GUV aspects of light & health. I’m curious if you envision Korrus moving into other areas of active research for light & health, such as migraines, depression and other non-circadian light therapies?

Reynosa: Yes, this may be is a good point to clarify the mission that we are on. The way that we describe ourselves is that we’re pioneering a new industry called Human Light Interaction. As the name implies, what we want to understand deeply is all of the ways in which humans and light behave together, and how we might be able to provide or create technologies that enhance those interactions. That could be in the in the realm of diseases and illnesses. It could have to do with antiviral properties and material properties. Germicidal things that have to do with the lived environment and to optimize that from a physiological perspective. So we see our mandate as extremely wide, and we don’t even use the word “lighting” to describe the business. We use the word “light.” If you just pause for a second and just think about that, the distinction is quite different. In fact, we had part of our business development team at Display Week, this week in San Jose, showing our technology and our display applications. So televisions, monitors, smartphones, tablets, laptops, etc. When we think about the problems being encountered in modern society and the application layers of modern society, we see our mandate and vision really speaking to that entire opportunity set. The next logical question is that’s a gigantic market and opportunity set. So we try to be very disciplined in the specific areas that we want to target. But in terms of research abilities, we have a deep science and engineering team, exploring a very wide cross-section of modern dynamics and how we might participate in helping better the world through specific applications.

We have a culture of curiosity and exploration. If one of our scientists or engineers come upon something in the literature that they think is interesting, we give them the opportunity to go explore and understand that more deeply. It could be depression, Alzheimer’s, sleep, or performance, like an athlete. It is extremely wide.

Shiller: I personally see those non-circadian light therapies, for things like migraines, depression, etc. as potentially becoming much bigger business than circadian lighting, over the medium term, because it’s so debilitating, and it’s a bigger quality of life issue. Do you see those areas becoming big business or is it just too soon to tell?

Reynosa: Take a step even further out. I think the intersection of digital technologies, health, and wellness, which has even removed the word light, for a second. I think in the next 30 to 50 years, you’re going to see an ocean of new categories, industries, products, applications, and experiences at that intersection. At one level, Korrus is just a small microcosm of a gigantic wave coming from that direction, at that intersection. To your point, it is an overwhelmingly large opportunities, because since the Industrial Revolution, we’ve pretty materially divorced ourselves from the natural environment. Modernity brought in a lot of really wonderful things, but with that we brought on certain drawbacks and certain compromises that we think we can create a better balance with. We see our mission as elevating people’s understanding of their light diet, much in the same way they think about food, air and water. It’s literally that fundamental. And in the last 50 years, you’ve seen real revolutions, frankly, in all three of those,  where we believe light to be extremely misunderstood. And part of that is because 80% of everything that we know about human health and light has only been discovered in the last 20 years. The science is only now catching up with the truth and reality of the situation We’re trying to be at the forefront of that to help bring awareness and evangelize ways in which we can solve some of those modern ill effects, from divorcing ourselves from nature.

Shiller: We have been talking about human light interaction. Do you anticipate Korrus moving beyond human light interaction to other biological lighting, such as horticultural lighting or livestock and poultry lighting, that are non-human, but still biological.

Reynosa That’s a good question. Probably every three to six months, we get an inbound request, whether it’s from somebody in industry or academia, who is interested in exploring some of those intersections with our technology capabilities. After some explorations in that space, we’ve concluded that the intersections of humans and light is already overwhelmingly large. Opening the aperture up even larger, right now, would be a real distraction.

Shiller: Is there anything else that you’d like our reader to know about Korrus?

Reynosa: Thank you for that. I’d encourage people to go to to learn a little bit more about the market and the industry that we’re pioneering. There are a couple of videos. One that discusses human interaction with light and our mission. There’s a second video, under our science page, specifically on the intersection of humans and circadian health and well-being.

Shiller: Thank you for sharing your insights, Mark.

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An Interview with Christina Halfpenny – Diversity, Inclusion & Culture at DLC

I had the pleasure of interviewing Christina Halfpenny about her approach to women in leadership positions, at the Design Lights Consortium (DLC), and on the subject more broadly.

I had the pleasure of interviewing Christina Halfpenny about her approach to women in leadership positions, at the Design Lights Consortium (DLC), and on the subject more broadly. There are a large number of very accomplished women in leadership positions at the DLC – many brought on board after Christina Halfpenny became Executive Director in 2015. DLC has grown into an independent international non-profit that drives energy efficiency and connected building solutions through solid-state lighting and controls, across North America. Halfpenny has been a strong advocate for diversity and representation on panels at every DLC meeting for the past several years, and in the imagery the organization uses on its website and in materials.

Of the DLC’s 21-member staff, more than half (12) are women, including Dorene Maniccia and Leora Radetsky, both with numerous published papers to their names, and Bernadette Boudreaux who co-leads a Diversity Equity Inclusion and Respect (DEIR) in Lighting Working Group, with the DOE. Also, Liesel Whitney-Schulte has over 20 years of experience working on utility energy efficiency programs and collaborating with lighting designers to create programs that simultaneously fit utility goals and promote quality lighting design. Bios of all the women on the DLC team are here:

Shiller: More than 50% of DLC’s staff are women, despite the lighting industry historically being male-dominated. What advice do you have for other lighting industry executive leaders in a position to increase women’s representation, as well as diversity in hiring of all kinds (gender, race, sexual orientation, etc.)?

Halfpenny:  It isn’t just executive leaders in a position to hire women and diverse people. Every person in the hiring process can influence the diversity of their team, their vendors and suppliers, as well as leadership. Inclusion of people on hiring teams and questions from staff for prospective employees can help not only get a view into the organization’s dynamics, challenges and priorities, but also provide a relevant assessment of culture fit. These things can be overlooked if we are not taking a deliberate approach towards diversity in our hiring methods. With the ongoing changes in lighting and the industry, it’s an opportune time to prioritize diversity for the variety of perspective and experience that comes with a diverse team. There is always room for women and diversity in leadership; on Boards and in executive functions, but truly valuing diversity happens when space is made for diversity at all levels of the company.

Shiller: DLC has many recognized industry thought leaders on its staff, both women and men. Do you have any advice to other executives on recruiting and retaining elite industry talent, both women and men?

Halfpenny: On their behalf, thank you for the recognition. We are fortunate to have (and had) people on staff who are extremely knowledgeable and passionate about lighting and protecting the environment. Our team thrives on making a positive impact, and these folks leave their marks on the work we do and affect colleagues and peers in positive ways.

Ultimately, personal fulfillment leads to job retention. Look at the statistics of how many people recently left their jobs for something that paid less but provided more meaning and balance for them. Individuals also need to know that their contributions are valued by the company, however, we all know that individual performance is not the sole driver for success. I find that fulfillment from work comes not only from enjoying the actual work, but also the people.

Leadership at the DLC sets expectations for the entire team to contribute value and exchange ideas and feedback in a productive and respectful way. We prioritize an organizational culture that enables and supports collaboration, and collectively celebrates success, so that leading and learning are simultaneous for individual satisfaction and collective success.

Shiller: Are there ways that having a majority women staff has been advantageous to DLC? How has it changed the culture at DLC?

Halfpenny: Yes! As far as a change in culture at the DLC, we have always been a majority of women or 50%, and we have benefitted from a culture of support and respect. That culture generates increased capacity to listen and consider the impacts of our work on our stakeholders. While we prioritize collaboration internally, that resonates with our work externally with members, industry experts and stakeholders, which a key success factor for a Consortium.

In addition, having a balance of women in the organization brings more honesty about life outside of work.  For whatever reason, women are still juggling the majority of the home life – sick kids (and parents), doctor appointments, school activities, carpools, etc. – and we need to normalize that as a part of our lives. I hope if women can normalize it in leadership positions, and throughout the workplace, then men can too, and we will all benefit from a genuine work life balance.

Shiller: What’s your view of current efforts to increase women’s representation in lighting leadership positions? There are a couple organizations now working toward this goal (i.e. WILD, WIL, etc.)? Do you see specific women’s challenges that aren’t yet being addressed, in the lighting industry, that need to be addressed?

Halfpenny: Many of the women’s representation groups are providing much needed resources for mentoring, strategies to succeed and gaining visibility, particularly for younger women. There should be more efforts focused on inclusion and support to ensure that women and underrepresented groups have the resources they need to grow and be successful.

I do see many groups working on diversity who are made up of the diverse people themselves and that’s a little frustrating to see them doing all the work in this area. There have been a few changes in highly visible positions in the industry for women and diverse people, so change is happening, but we can’t lean on the minority to make it so. Everyone has a role to play in the change. As I mentioned previously, it’s in the hiring process, the procurement process and the values that shape the business culture.

Shiller: Thank you, Christina, for sharing your thoughts and expertise with our LightNOW readers.

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NEMA Luminaire Section UGR Task Force Chair Jeremy Yon Talks Glare Metrics

I recently had the opportunity to interview Jeremy Yon, Industry Relations Leader, GE Current, a Daintree company, and Chair of the NEMA Luminaire Section UGR Task Force, on the topic of application of the Unified Glare Rating (UGR) metric. Transcript follows.

I recently had the opportunity to interview Jeremy Yon, Industry Relations Leader, GE Current, a Daintree company, and Chair of the NEMA Luminaire Section UGR Task Force, on the topic of application of the Unified Glare Rating (UGR) metric. This interview was conducted to inform an article that will be published in the September 2022 issue of ELECTRICAL CONTRACTOR, the official publication of NECA. Transcript follows.

DiLouie: NEMA recently published LS 20001-2021, a whitepaper concerning current use of UGR as a glare metric. What was the rationale behind producing this whitepaper?

Yon: Glare is a timeless and universal concern to everyone who cares about lighting. It is one of the most critical aspects of an occupant’s experience with lighting and one of the most devilishly difficult topics. Historically, glare comes in and out of fashion. Because LED efficacy is now slowly increasing, glare is returning to the forefront of the industry’s attention. This topic has been grappled with by true lighting visionaries in the past, and now my NEMA colleagues and I are attempting to re-structure how glare is thought of and talked about so that there can be a common understanding and vocabulary when working together with all stakeholders.

DiLouie: What does UGR, overall and in general, reliably deliver, and what are its limitations?

Yon: The broad aim of UGR is to provide a better way to evaluate glare in indoor settings. However, it is not a simple matter because UGR depends strongly on the specific application; not only in regards to the luminaires, but also in their layout, the shape of the room and the reflectances of the surfaces in the room all affect the value of UGR. Additionally, the location of people in the room and the tasks conducted within the room can affect the experience of glare as well, so different values of UGR may be desired in different applications.

Therefore, we believe much of the confusion and misunderstanding when it comes to UGR is due in part to the three different ways that the term is used – they each have their own purposes and limitations. Since they were unnamed previously, we’ve taken the liberty to recommend that they be called Application UGR (UGRAppl), Luminiare UGR (UGRLum), and Point UGR (UGRPoint).

We’ve come to understand through our research that Application UGR and Point UGR can be tools for lighting designers to get predict what will likely be the visual comfort level for specific locations within an application. These are not absolute determinations and must be balanced with other predictive factors. Application UGR was designed while, and works best when, considering a windowless rectangular room with regularly spaced luminaires (think troffers). Point UGR is possible with computer simulations, but it should not be evaluated by looking at each point as it requires averaging over an area by the user to achieve the intended indication of comfort.

Luminaire UGR is the most common use of the term today and is the most problematic use of the equations. The UGR methodology was not intended to be an absolute measurement. The Luminaire UGR approach does this by forcing an evaluation of a single luminaire type in a specific evaluation space without taking into consideration the space itself (geometry, room finishes, luminaire placement, windows, partitions, multiple luminaire types, etc.). It cannot appropriately predict the likelihood of glare in any space other than that single specifically required condition. NEMA advises strongly against using Luminaire UGR.

DiLouie: What are the most common misconceptions practitioners have about glare and UGR, and what is the reality they should understand?

Yon: I think the most common misconception is to assume that a luminaire can have a UGR rating, ignoring the role of the application. If you look at a table of values produced by the tabular method for a single luminaire, you will see that, depending on the light distribution of the luminaire, the UGR can vary greatly. It clearly does not depend only on the luminaire. Below is an example in which UGR varies from 2.6 to 21.8.

While some may claim that UGR is the best of the various limited glare evaluation tools, that doesn’t mean UGR can deliver more than it is capable. Unless properly evaluated for the specific application in which a luminaire will be used, it can’t give absolute assurance that the luminaire selected is going to meet the required lighting design criteria. To this point, some manufacturers refuse to put Luminaire UGR numbers on their cutsheets. They don’t want to contribute to a misuse of the UGR metric, nor have their customer be the victim of poor lighting design quality because of a misapplied UGR number.

DiLouie: DLC, LEED, and WELL specify a maximum UGR based on glare emitted by the luminaire (UGR-Lum). This offers an advantage of reducing glare to a simple number published on a catalog sheet. NEMA says there are significant disadvantages. What are they?

Yon: All of those rating programs use the Luminaire UGR simplification to get the single value you mention. This creates a situation where a designer thinks they are selecting a product that has the “right number,” but in actuality, they may be selecting one that has more glare than is desired in application. From the example given earlier, the tabular reporting of that luminaire had a range of values from 2.6 to 21.8 – just based on room size and no other factors. With a variation this wide, it simply makes no sense to try and represent a luminaire with a single number.

Because of the selection of only a single reported value, there are many factors that impact the visual experience found in the final application that are not incorporated into Luminaire UGR. Some examples include the room finish (a dark ceiling will be much different than a light ceiling), the luminaire mounting height (high-bay vs office), and non-uniform placement (troffer grids vs artistic slots).

At the same time, luminaires that are designed to achieve only a Luminaire UGR value, and not to minimize glare from an application approach, can have various consequences. The luminous surfaces of the luminaires may be less uniform with easier-to-see LEDs, there may be additional accessories that need to be installed and there may be a feeling that the final spaces are darker, even though there may be adequate horizontal light (some may remember the deep-parabolic troffer days of the 1980s).

DiLouie: NEMA believes UGR-Appl, adopted by ISO and EN 12464-1, is a more appropriate metric to use to predict glare in a space…

Yon: NEMA is saying that UGR should be used in the way intended by the original CIE documents. Simplifying it to a luminaire based value is not correct.

DiLouie: Some organizations utilize UGR-Point, which predicts glare at a point in the space. This similarly places the metric in the space, not at the luminaire, but NEMA cautions about its use. Why?

Yon: Simulations will produce an array of point UGR values in a space. The original UGR uses a “trick” to calculate the average UGR over a 1H x 1H square centered along the walls. If only point calculations are done, as simulation software typically does, then the averaging step is omitted. Judicious positioning of the luminaires and/or the point for calculation can result in large variations in the UGR. “Cherry picking” from a set of UGR point values can yield a misleading value for UGR.

In examples given in the NEMA paper, UGR tables include a variation expectation that is often overlooked. These show expected point-to-point variation values, depending on the spacing of the luminaires. In the example we provided, the variation ranges from a minimum of +3/-3 units to +7.5/3.8 units, making a comparisson against a threshold impossible.

The user of a piece of software should perform proper averaging, either as detailed in the UGR standard (in a 1H x 1H region at the center of two adjacent walls) or in certain situations where occupants are only in specific areas, such as custom areas that best represent their design objectives. Secondly, there are some ambiguities in the UGR standard around handling different sizes of luminaires that can lead to differences between software simulations.

Finally, and most importantly, the designer needs to balance the results with all the other aspects of a lighting design – vertical illumination, presence/design of windows, space use flexibility, circadian exposure objectives, etc.

DiLouie: If UGR-Appl is most advantageous in predicting glare, a challenge is that the procedure appears to be complex and not well understood. What is the solution for this?

Yon: It is complex and not well understood! The fundamental CIE UGR standard (117) has been around since 1995. But oversimplifying it will lead to artificial selection of some luminaires as “good” and others as “bad,” when in fact the goodness/badness is impossible to evaluate outside of the context of the application. With the absence of a simple answer, it is good for all of us to remember that lighting, by definition, is a blending of art and science. This balance is what makes it so interesting and engaging for most of us.

The first recommendation is that luminaires should be used in the manner in which they were intended; if a high bay luminaire is used in an office, there is probably going to be a difference in visual comfort than if a luminaire designed specifically for an office is used. Building on this notion, manufacturers play an important role in determining what appropriate use is. The literature should be clear, and specifiers should ask for details they feel will help complete the project. A qualified lighting professional should be used to bring together all the complexities of lighting into an optimized solution.

Finally, and most importantly, all stakeholders need to come together with researchers to provide consistent and actionable recommendations. The IES is tackling this for some product categories and there is hope for continued engagement. Internationally, there is still work to be done by the CIE.

DiLouie: How should electrical contractors evaluating lighting systems approach it in regards to ensuring a product will not produce objectionable glare? Are there rules of thumb for evaluating application glare?

Yon: The most important rule of thumb is that glare, at its essence, is related to the difference between a bright object and a dark background. This is easy to see in daily life – high-beam headlights that can be disabling at night are barely visible during the day. The first step is to factor in the surfaces around the luminaire – are they light or dark finished? Is there light from other sources hitting the surface to keep it from being dark? The luminaire should fit into those needs by providing diffuse light in circumstances where an overall lighter environment is warranted, controlled and shielded when a dark atmosphere is expected.

It always helpful to think of the extremes – a soft white uniformly backlit luminous ceiling and white walls (if not overly bright) can have almost no glare (to the point that it can be disorienting); whereas a black-box theater goes to extremes to hide the source of the light so as to not draw attention away from the performance. Similarly, luminaires for offices would most likely be expected to have a uniform appearance and contribute to lighting the walls and surfaces, while task-specific lights (such as a wall-wash or a high-bay warehouse aisle light) rely on precision optics that need to be coordinated with the overall viewing expectations of occupants.

DiLouie: What other solutions does NEMA recommend as a way to ensure lighting systems are designed and delivered that minimize glare while serving the best needs of the application?

Yon: The first is to recognize how UGR can be both properly and improperly utilized as a guidance method for good lighting design. We’re hopeful that through the NEMA whitepaper, it is understood that only Application UGR provides suitable guidance in terms of what an occupant will experience in a specific space. In addition, if simulations are done, the individual point UGR values should not be utilized (averaging should be done) and there are assumptions about large and small luminaires that may lead to variations of answers in different software platforms.

Certainly, there is more study and work to be done to improve how we predict glare. It is hopeful that further focus and effort can be made that will simplify how this is done. Yet for now, Application-UGR remains our best option. What we don’t want is a misunderstood lighting metric, such as Luminaire-UGR, being used in good faith efforts to simplify the situation, as this will result in poor outcomes in lighting performance.

DiLouie: If you could tell the entire electrical industry only one thing about UGR, what would it be?

Yon: Our message to the industry is that UGR is an imperfect predicter of glare, but Application UGR is the best method we have today. With the right understanding, it can be an asset to lighting design application. If UGR’s limitations are not understood, such as using Luminaire UGR as a singular number inaccurately across a variety of applications, it undermines the purpose of the metric and can result in poor lighting.

DiLouie: Is there anything else that you’d like to add about this topic?

Yon: NEMA members place a high value on the visual environments our luminaires create. We work together with designers, installers and users to balance the needs of an application to create the most appropriate experience. Balanced factors like efficacy, color rendering, color temperature, uniformity, light distribution, color consistency, etc. all can have different impacts on the perceived glare for each specific application that cannot be factored into a single-value luminaire value.

NEMA welcomes the opportunity to work with all the stakeholders in evolving means to both predict and communicate expectations for visual comfort. Today, Application UGR and averaged Point UGR calculations can be an effective part of an overall lighting design, but they are very limited and should not be applied as a luminaire selection tool.

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