Eaton’s Wegner and Broughton on LED Optics

I recently had the pleasure of interviewing Scott Wegner and Kevin Broughton, principal optical engineers for Eaton. The topic: LED optics. I’m happy to share their responses with you here. The interview informed an article I wrote for the June 2016 issue of tED.

DiLouie: What is the purpose of an optical system, as applied to a light source in any luminaire or directional lamp?

Wegner and Broughton: The optical system redirects the uncontrolled light emitted from a light source into a controlled beam or distribution specifically formulated for a given task.

DiLouie: What optical approaches are common for traditional fluorescent, HID and incandescent/halogen luminaires and directional lamps?

Wegner and Broughton: Traditional fluorescent, HID and incandescent/halogen sources emit light in all directions. Reflectors are very common for these sources, as a large amount of energy can be captured and redirected. Refractors are less common for directing light into a specific light pattern, as a reflector is also generally required. Lenses are often used to disperse or diffuse light and minimize direct view of the light source. High heat from HID lamps typically necessitates using glass.

Jun-2016_TED-LED-optics-DiLouie-1DiLouie: What optical approaches are common for LED luminaires and lamps? Why were these approaches developed?

Wegner and Broughton: LEDs are unique because they are Lambertian light sources (i.e. hemispherical output). Reflectors are less effective since only a small fraction of energy can be captured compared to traditional sources. Refractors are more commonly used with LEDs. Due to their low temperature, polymers may be used to form small, precise features impossible for molded glass.

DiLouie: What are the benefits of these optical approaches compared to optics for traditional products?

Wegner and Broughton: Because LEDs emit light only into a hemisphere, a refractor or lens can completely encompass the LED, gathering all the energy for redistribution. The optical efficiency is very high, commonly 90-95 percent, compared to 75-87 percent with optics of traditional sources. The geometry of an LED is tightly controlled and as such, optical distributions can be considerably more precise than luminaires with traditional sources.

DiLouie: Based on relative performance and cost, what applications are targeted for each LED optical approach?

Wegner and Broughton: Due to significant drop in costs as well as the extremely long operating life, LEDs are slated to replace all traditional sources in all applications.

Exit and Emergency:
LEDs have been offered in exit signs for years due to their high efficacy in green and red. Emergency luminaires benefit from the high efficacy of LEDs, long life and DC operation, which simplifies driver designs.

Recessed: For indoor architectural lighting applications, recessed luminaires were the logical choice to serve as an alternative to incandescent and fluorescent sources. In addition to the obvious energy savings, LED sources are easier to control than fluorescent lamps and make dimming luminaires much easier.

Area and Roadway: Area and roadway lighting are the most demanding applications for optical control. In addition to their high efficacy, LEDs are small, allowing for precise optical control and have an advantage compared to traditional sources.

Troffers (formerly linear fluorescent):
This product type is the most recent adoption of LEDs due to the long life and cost of linear fluorescent lamps as well as a lesser need for precise optical control. As costs have continued to drop, and the desire for building controls has increased, LEDs have become the logical choice for ambient lighting.

Jun-2016_TED-LED-optics-DiLouie-2DiLouie: What are the top three trends in LED optical design?

Wegner and Broughton:

1. Refractors for wide distributions such as those for area and roadway luminaires, and low bay or high bay applications
2. TIR (total internal reflecting) refractors for narrow beam distributions, floodlighting, and sports/stadium lighting
3. Edge-lit panels distribute light over a broad surface to minimize glare. High-end indoor and outdoor architectural applications benefit from the uniform, low glare appearance.

DiLouie: Some manufacturers are offering 3D printed optical systems allowing optics to be made to individual specification. What are the pros and cons and target markets for this offering?

Wegner and Broughton: 3D printed optics are produced directly from CAD solid models, without the need for molds. The setup can be done in several hours and optics delivered to the customer in less than a week. A timely speed to market without a penalty for low volumes is a major benefit for any fledgling industry. This is in stark contrast to the traditional method of injection molded plastic, which requires expensive tooling taking weeks to machine. Injection molding requires large product volumes for reasonable part costs, which poses a risk if rapid adoption of a new product is uncertain. 3D printed optics are deposited on a flat transparent substrate. Hollow voids in the optic are not possible at this point. Typically, both the inside and outside surfaces of a refractor are used to control light. In this case, only one surface can be curved to modify the light distribution thus limiting control. However, it is possible to flip the substrate over, printing on both sides of the substrate for more complicated geometry. Today, there are limits to the maximum optic height and minimum feature size. Sharp details cannot be reproduced. The current materials are somewhat temperature sensitive and can degrade over time if used in close proximity to high power LEDs and are not UV stabilized.

DiLouie: Some manufacturers are now offering TIR lenses for chip-on-board arrays. What are the pros and cons and target markets for this offering?

Wegner and Broughton: For discriminating applications, such as museums, it is desirable for lighted objects to produce sharp, crisp shadows. A plurality of individual optics produces multiple shadows instead of a single defined edge. A single optic for chip-on-board arrays (COB) creates a single shadow. The optic does need to increase in size, however, proportionally to the source size and eventually reaches the limit of manufacturability. A larger optic is inherently more expensive.

DiLouie: What is the overall trend in LED optical design? What will LED optics look like in 3-5 years?

Wegner and Broughton: The practicality of LED optics has already been identified. In general, the optics will not be significantly different from what is produced today. We may see more versatility in materials. Glass is extremely resilient to extreme environments and UV exposure. Optical silicone, since it is flexible, can be molded with slight undercuts that would be expensive to mold with rigid materials. It is possible some optical distributions might be further refined and perfected.

DiLouie: What is the main thing distributors should understand about optics when selling LED products to their customers?

Wegner and Broughton: LED optical systems are much more consistent than traditional sources, especially HID sources. When purchased from reputable manufacturers, the customer can expect to get high quality and consistency without the variability seen by using lamps from different manufacturers.

DiLouie: If you could tell the entire electrical industry just one thing about LED optics, what would it be?

Wegner and Broughton: When compared to traditional light sources, LED optics are highly efficient, precise and consistent. They have the ability to control and distribute light where it is needed with better uniformity and can be tailored to meet a broader number of applications.

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

Wegner and Broughton: LEDs are here to stay. There is no other technology waiting in the wings threatening to make LEDs obsolete.

A History of Recessed and Track Lighting

Eaton has published an article describing the history of recessed and track lighting. Check it out here at the Eaton’s The Lighting ReSOURCE.


World’s Blackest Spray Paint

paintSurrey NanoSystems now offers a spray-on version of its Vantablack coating, which it first released two years ago. Vantablack is constructed of carbon nanotubes that absorb light–99.965% of the light that strikes it, in fact. The result is three-dimensional objects appear as two-dimensional.

Check it out here.

The Lighting Solutions Center at Hubbell Lighting Announces 2016 Schedule


Hubbell’s 25,000-square-foot lighting solutions center, located in its Greenville, SC headquarters, has announced its education schedule for 2016. Click here to learn more and register.

Retrofit/Create Change Workshop – Jul. 19-20
This two- day class will help attendees understand when to convert from legacy technology to LEDs. A hands-on workshop will simulate a building audit and show the impact that controls, maintenance, and rebates can have on ROI (Return On Investment). Opportunities for future retrofits and forward compatibility will be explored. CEUs will be available for attendees.

LitePro DLX Workshop – May 12-13, Aug. 18-19, Nov. 10-11
This fast-paced workshop is intended for application engineers and specialists or sales representatives who prepare design calculations and specifiers who evaluate lighting designs. Participants will experience first-hand that with the LitePro DLX software you are able to design lighting which is not restricted by the boundaries between rooms and spaces. In this course you will learn how to deal with architecture as a whole – starting with a rectangular room, moving on to planning a complete floor and then a whole building and its surroundings. You can create your design from scratch or based on an imported file. Attendees will learn to create light scenes with dimming levels and changing colors and produce professional documentation with explicit calculations and photorealistic images. Participants will work on a laptop and will be led through the program by experienced trainers who work with the program themselves. The modular structure of the seminar allows you to work individually on a practical task according to your own present level of knowledge. *Participants should plan to bring their own laptop if possible. LitePro DLX software will be provided.

Fundamentals of Lighting – Jun. 8-10, Sep. 13-15, Dec. 7-9

Designed for professionals new to the lighting industry or seasoned professionals looking for a refresher, this three-day workshop focuses on the fundamental principles of lighting and introduces today’s latest advancements in lighting technology. Through hands-on training and real-world applications, we take an interactive approach to educating our participants in general lighting terminology, lamps and ballasts, solid-state lighting technology, light, vision, and color, optical control, and basic application principles.

Basics of Lighting Controls – Sep. 16
This one day course is focused on the basics of lighting controls. Through this program participants will gain an understanding of various control solutions including motion sensing, daylight harvesting, panelbased lighting control systems, and wireless lighting control systems. In addition, participants will also be exposed to the current legislation and building codes, such as ASHRAE, IECC, and California’s Title 24, that are changing the controls landscape. At the end of this course participants should be able to identify opportunities in various applications for a lighting control system, specify the control requirements based on the lighting fixture criteria, and recommend an appropriate solution based on the application requirements.

LEDs & Emerging Technologies – Nov. 1-2
This 2-day course will discuss the ever-increasing LED market and the speed at which LEDs are quickly being integrated into lighting applications. Participants will gain a basic understanding of how LED components are integrated into lighting fixtures and how well LEDs perform in particular lighting applications. Additional discussion includes newer technologies just emerging such as OLEDs, solar and wind technologies, and various other technologies that could impact the lighting industry in measurable ways. Participants will also take part in a mini-workshop, designing and building LED fixtures.

Lighting for Commercial Applications – Oct. 6-7

This two day class will look at the latest IES requirements for commercial applications in both indoor and outdoor enviroments . Potential topics will include office buildings, education facilities, retail and hospitality. This application based class will cover the latest lighting technologies as well as legacy sources and integration of controls. Course will feature site visits and evaluations. CEUs will be available for attendees.

Lighting Solutions & Applications Workshop – May 10-11, Oct. 27-28
This fast paced product solutions workshop is for the experienced lighting professional and those new to the industry. During this two-day, hands-on and application-based workshop participants will gain additional insight into Hubbell Lighting’s portfolio of commercial and industrial product solutions for interior and exterior applications.

Lighting for Healthcare Applications – Sep. 29-30

Lighting for Healthcare Applications is a two- day interactive class that addresses integrated lighting needs for the patient, guests, and employees in a healthcare setting. Attendees will learn about the psychology of light, and lighting for various applications. There will also be discussions on current lighting research, circadian rhythm, vision, color, and special applications.

Lighting for Industrial Applications – Nov. 15-16

According to Department of Energy studies, industrial spaces consume nearly one-third of all energy used in the U.S. Estimates show that lighting in these industrial spaces to be of significant age, many 20 years or older. As upgrades are considered, lighting offers the fastest internal rate of return with the lowest investment. This course will explore the best lighting solutions for new and existing spaces. Participants will explore existing and emerging lamp technologies to understand the best approach to take for industrial applications. Further discussion will include lighting audits, incentives, economics, current legislation, and future innovation. This course is ideal for facilities managers, facilities owners, industrial consultants, energy service providers, engineers and all other industry consultants.

Product Monday: FineTune White Color Tuning by Finelite

The FineTune White Color Tuning System developed by Finelite enables white color tuning in 12 LED luminaire families, from pendant and wall-mounted to recessed and cove. For optimal operation, the award-winning system includes drivers and controls that allow granular settings for color temperature and lighting intensity levels.

FineTune enables CCT color tuning from 2700K to 6500K and dimming from 1% to 100%. DMX controls support an intuitive user interface with preset CCT and dimming levels, simple up/down arrows for more granular control, and a digital display of CCT, as well as a smart app—available in iOS and Android—that communicates via Bluetooth. (Other DMX, DALI, or PoE controls may be used.)

The FineTune System is preconfigured for occupancy or vacancy sensors, and one, two or no daylight sensor-controlled zones. All connections are made via the plug-and-play cables provided.

Click here to contact Finelite.


BriteSwitch’s Enthoven on Lighting Product Rebate Trends

I recently had the pleasure of interviewing Leendert Jan Enthoven, President of BriteSwitch, a utility rebate fulfillment company. The topic: lighting product rebate trends. I’m happy to share his responses with you here. The interview informed an article I wrote for the April feature article for the Lighting Controls Association.

DiLouie: How would you characterize the current lighting rebate opportunity in the United States in 2016? What is the current overall trend in funding?

Enthoven: Rebates for commercial lighting are as strong as ever. While funding overall has remained strong, we did notice that in 2015, more rebate programs than ever ran out of funding due to increased levels of participation.

DiLouie: What is the typical impact of a lighting/control rebate on a retrofit project? What percentage of the product and/or installed cost does it typically cover?

Enthoven: Rebates typically improved the payback of a project by 20-25% so a project that used to have a 2 year payback could come in around 1.5 years. In some areas, rebates can cover up to 70% of the cost of a product but that is far from the norm. You really have to know your local programs.

DiLouie: What are the top 3-5 trends in lighting rebates and what impact are they having on demand for energy-efficient lighting?

Enthoven: In 2016, we saw a lot of rebate programs start to shift their focus away from screw in LED replacements to LED tube replacements for fluorescents. While these types of products may have been covered by custom rebates in the past, the new prescriptive amounts are typically higher.

Rebate programs have continued to require Energy Star or DLC approved products, which drive the demand for high quality LED products

Rebates for LED lighting have continued to decline to match the shift in prices but not as much as previous year. Last year, rebates went down 20-30%, this year was a more modest 5% decrease.

Most popular prescriptive rebates in 2016 from the BriteSwitch North American Rebate and Incentive Database, as of March 29, 2016. Data courtesy of BriteSwitch, LLC.

Most popular prescriptive rebates in 2016 from the BriteSwitch North American Rebate and Incentive Database, as of March 29, 2016. Data courtesy of BriteSwitch, LLC.

DiLouie: What are the top 3-5 trends in lighting control rebates and what impact are they having on demand for lighting controls?

Enthoven: With lighting controls, we’re noticing more programs focusing on integrated fixture sensors since they work so well with many LED products.

What’s very interesting is that rebates for lighting controls have remained remarkably stable. Over the last 5 years, the rebate amounts have only decreased by 10% which is unheard of in any other lighting category.

Wireless control products continue to gain acceptance in more rebate programs. Up until a few years ago, program rules required that lighting controls were hardwired, but with the advancement in wireless technology, many rebate programs have removed this requirement.

DiLouie: What is the overall trend with non-LED energy-efficient rebates (such as low-wattage and high-performance T8)?

Enthoven: Incentives for non-LED lighting products are still offered by many rebate programs but they’re not as highly publicized as LED products. There are still a ton of rebates out there for T8, fluorescent highbays, and induction fixtures. The rebates have gone down a bit over the years, but they still cover a good portion of the cost of these solutions. Customers really have to weight their options, with a lower cost and solid rebates, some of these more traditional technologies will have a much better payback than the more trendy LED solutions.

We have noticed that many programs are changing how they view upgrades from T12 lighting. Since the programs feel customers have no choice but to upgrade from T12 lighting, they’re providing reduced incentives, or using T8 as a baseline for the energy savings to calculate the dollar amounts.

DiLouie: How would you describe the growth in utility rebates promoting LED lighting technology? How many states and programs are available, what is the total funding in 2016, and how does that contrast against previous years?

Enthoven: LED technology has come to be a favorite with rebate programs. Most rebate programs have added prescriptive rebates for many categories of lighting such as screw in lamps, LED tubes, high bays, exterior lighting, etc. Currently, 64% of the US is covered by a commercial lighting rebate which is down from 71% last year.

DiLouie: How would you describe the growth in utility rebates promoting lighting control technology? How many states and programs are available, what is the total funding in 2016, and how does that contrast against previous years?

Enthoven: Lighting controls rebates have remained remarkably consistent over the years. The rebates still cover a very significant portion of the cost of controls and, along with the energy savings, make it a great opportunity to sell to customers. Most commercial lighting rebate programs provide incentives for controls.

DiLouie: Is there anything significant to report about incentives other than product rebates, such as demand response, rebates based on kWh and kW reductions, etc.?

Enthoven: Demand response and other such programs vary greatly by area and year. We haven’t noticed anything notable about these programs this year.

DiLouie: What are the obstacles to obtaining rebates, and how can lighting professionals overcome them?

Enthoven: Probably the biggest obstacle that prevents customers from getting rebates is not pursuing pre-approval prior to installation. A lot of people will install their new lighting and then try to file for rebates, but in reality most rebate programs have a pre-approval requirement where you must file paperwork before installation in order to get money.

Another obstacle many people face is not using the right products. Most programs have requirements that products must meet in order to qualify for rebates. For example, if a customer used a non-Energy Star listed LED lamp, they would be automatically excluded from 94% of the prescriptive rebate programs currently available. Other solutions may need to be on the DLC or CEE approved lists. For lighting controls, they may specify number of fixtures or watts controlled in order to qualify for rebates.

Also, if you don’t fill out the application paperwork properly, you may get stuck in a very time consuming, administrative application process where many people eventually give up out of frustration.

DiLouie: What are the top three things lighting professionals need to know about when helping their customers capture rebates?

Enthoven: When suggesting products to customers, make sure they meet the requirements of the rebate programs. Just because a spec sheet says a product is Energy Star or DLC listed, it is not always true. The exact product must be actively listed on the EnergyStar or DLC website.

Pre-approval is needed in about 80% of programs. If a customer removes the old lighting before pre-approval is received, they will miss out on that rebate.

Rebate programs receive thousands of applications a year. Be prepared for a lot of follow up to make sure your application makes it through.

Rebate programs can change or run out of funding at any moment. Make sure you check them frequently so you don’t overpromise rebates to your customers.

DiLouie: What is the biggest mistake owners and/or lighting professionals make when trying to gain a rebate? What should they do to avoid it?

Enthoven: The biggest mistake people make when trying to get rebates is not getting pre-approval before ordering or installing the new lighting. People will spend months debating a project and then once they decide to pull the trigger, they forget they need pre-approval. Pre-approval takes 31 days on average and is often required. If the work begins before pre-approval is granted, the rebate is usually forfeited.

DiLouie: What are the major qualifying organizations—such as DLC Qualified Products List, ENERGY STAR, CEE—and the latest requirements? How are they setting the bar for products being installed in retrofits?

Enthoven: Rebate programs often specify 3rd party qualifying organizations to ensure that products meet certain technical requirements. Energy Star, Design Lights Consortium (DLC) and CEE are the biggest, but this year we saw several programs start requiring products to be on the Lighting Facts list as well.

While DLC has recently created a “premium” category for products, right now there are very few programs that require or provide an additional incentive for products in this new category.

DiLouie: If you could tell all lighting professionals only one thing about lighting rebates, what would it be?

Enthoven: Lighting rebates are one of the best sales tools you have to help convince customers to go through with an upgrade. It helps decrease the cost to the custom without reducing your margin. The key is to always focus on the price after the rebate.

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

Enthoven: Because the rebate process can be so time consuming and complicated, many contractors and distributors work with rebate processers to help get rebates and incentives for their customers. By partnering with these rebate processors, the contractors are able to provide accurate rebate estimates to the customer and have the whole handled with no hassle. We regularly partner with contractors and distributors who want to help their customers offset the project costs with rebates but can’t dedicate the time and resources pursuing rebates for the customer.

NEMA Business Conditions Indexes Up Sharply in March

NEMA’s Electroindustry Business Conditions Index (EBCI) for current conditions in North America surged in March, climbing to 64.7 from 44.4 the previous month as more panelists reported conditions improved than eroded.

Compared to February, a larger share of the survey panel reported that business conditions improved (41% in March compared to 22% in February) and a smaller share reported that they deteriorated (12% in March compared to 33% in February). Forty-seven percent claimed conditions were unchanged in March, similar to the share holding this view a month ago.

The survey’s measure of the intensity of change in electroindustry business conditions also improved markedly in March, swinging to +0.5 from -0.2 in February. Panelists are asked to report intensity of change on a scale ranging from –5 (deteriorated significantly) through 0 (unchanged) to +5 (improved significantly).

The EBCI for future North American conditions also improved in March, rising to 61.8 from 52.8 in February. A slightly larger share of the panel (35%) reported positive expectations than was the case last month (33%), while a substantially smaller share (12%) reported negative expectations than was the case in February (28%). The share expecting to see no change in business conditions over the next six months rose to 53% in March from 39% in February.


Registration Open for Rocky Mountain Lighting Academy


The RMLA Technical Course will be offered for the fourth time June 9-12, 2016, and continues to offer an intensive exploration of the fundamentals of vision, perception, lighting metrics, photometry and optics with an introduction to the aesthetics of light and lighting design.

In addition to the fundamentals, this year’s course will also feature an in-depth discussion of the new IES TM-30 color quality metrics as well as an expanded discussion on the non-visual effects of light.

And being introduced in 2016 is the new RMLA Design Course. The Design Course emphasizes how to develop strong design concepts for interior and exterior lighting applications, and how to integrate an understanding of new lighting technologies and of lighting’s human impacts into those concepts. Like the Technical Course, the new Design Course balances lecture content with lots of hands-on practical problem solving.

Click here to learn more.

Transparent Wood Could Transform Architecture

A Swedish scientist has created a treatment for wood that renders it nearly transparent, which will allow architects a potential new way to bring daylight into buildings.

Check it out here.


Product Monday: Vessel by Humanscale

Workstation task lighting provider Humanscale recently entered the architectural lighting market with its acquisition of Vessel, an architectural lighting solution from designer Todd Bracher that has won eight awards, including Best of NeoCon Gold. Available to ship in May, this clear cylindrical light is made of quartz crystal, providing glare-free illumination in a simple, refined form.

Installed as a single pendant or in large groupings in chandelier applications, Vessel provides an elegant solution for installations ranging from corporate to hospitality and residential. It is also available in a sconce form.

Contact Humanscale to learn more.