March 2019 – LED Journal

Lamp

Improvements in LED Lamps

Fardin Posted on March 27, 2019January 19, 2021

The LED lamp retrofit market continues to be a much sought after arena with more and more players entering the market. With an abundance of choices available, it is important to do your research to understand some key parameters of these novel light sources. This will help to find a LED lamp solution that not only fits your current needs, but also those in the future.

Have you ever wondered why the LED lamp that you just bought to replace your typical incandescent or halogen bulb is so much heavier? It is because of the need for thermal management in the LED lamp and the associated use of a heavy heat sink. Contrary to popular notion, LEDs do generate heat and unless that heat is dissipated properly in the lamp, the LEDs can heat up leading to lower lumens, lower energy efficacy, shorter lamp life and shift in color. Most LED lamps use a mass of shaped die cast aluminum as the heat sink material. However recent innovations in thermal management by some companies have enabled substantial reductions in LED lamp weight. This involves sophisticated thermal modeling and use of alternate forms of metal fabricated by different methods.

The LEDs in a solid state lamp are driven by DC but the socket into which the lamp is screwed is powered by AC. Electronics located in the LED lamp convert the AC into DC. Here, too, not all LED lamps are the same. Some innovative companies are using sophisticated electronic circuitry, which leads to high power conversion efficiency so that much less electrical energy is lost as heat in the circuit components and more is available to drive the LEDs. This leads to higher LPW (Lumens per Watt) and a more energy-efficient lamp.

The quality of dimming is another parameter that differentiates LED lamps from different suppliers. Robust dimming is the new trend among reputed suppliers who design their LED lamp electronics in such a way as to be compatible with a wide variety of leading edge dimmers. Flicker is minimized and the lower limit of dimming is on its way down to about 5 percent or less.

Many people love the warm tone that results when you dim an incandescent lamp. Do you wonder if this nice ambiance can be achieved by dimming a LED lamp? The answer is: yes, it can be done. Using advanced technology, a few forward-looking companies have recently introduced LED lamps with this special effect. This is essentially done by using proprietary algorithms to vary the current through two or more strings of LEDs of different color temperature using specially designed driver electronics.

How about effortless interaction with the LED lamps in your house? Would you like to switch your lamps on/off and dim them using a smart phone? Would you like to have the ability to do this remotely, say from your office? Would you like to set lamps in different rooms to different scenes? All of this is possible with wireless LED lamps. These lamps incorporate a radio frequency (RF) controller board in the lamp along with the driver electronics. A hub located in the house talks to the radio in the lamp using a wireless protocol like ZigBee and using a smart phone and the web, one can control all the wireless lamps in the house. Some innovative companies have recently introduced such lamps for the retail market.

It is important for the consumer to realize that not all LED lamps are created equal. LED lamps incorporate a wide variety of technical disciplines: materials, thermal management, electronics, optics, LED and process engineering. The best providers are able to design high performance into the product at a good value.

Lighting

Historical Use of Glass in Lighting

Fardin Posted on March 21, 2019

Artificial lighting has been one of the most valuable technologies ever invented and commercialized, beginning with oil lamps in c. 4500 BC, street lamps in 900, Edison’s incandescent bulb in the 1870s and LED today. Now, with the widespread adoption of LEDs, lighting is again pushing technology, functionality, comfort and now energy efficiency forward to improve our daily lives. Despite the vital role glass has played for centuries as a valuable component of artificial lighting, however, it has been missing during the LED generation and gone largely unnoticed.

Infographic by Designbysoap

Glass has been a constant presence in lighting since lanterns and street lamps first appeared on the scene in the 1700s, providing protection to both the lighting source (oil or gas) and those in close proximity to it, creating both a functional and safe solution. The incandescent bulb came along at the start of the 20th Century, becoming the essential shroud around this new jewel of lighting that would dominate and reinvent the world over the next 100+ years, providing an inert vacuum environment to protect and sustain the lighting source for long life and reliability. With the commercialization of high-performance High-Intensity Discharge (HID) and Mercury vapor commercial lighting technologies, such as High-Pressure Sodium and Metal Halide in the 1950s, glass served an added protective function along with projecting the light source. Glass was then and is now a translucent, durable material with the ability to provide light transmission while offering long-term protection to and from a light source emitting high levels of Ultraviolet (UV) and Infrared (IR) energy that would easily degrade a lesser material. In addition, the thermal strengthening or tempering of glass provided and extra measure of safety in case of breakage in the field. This partnership of light source technology and glass allowed for HID-based commercial lighting in applications such as sports and entertainment; roadway, street and area lighting; and industrial areas to flourish for the next 50 years.

At the turn of the century, as it happened a century earlier with Edison, an exciting new lighting technology began to make its way into the market. Although the first LED was invented in the early 1960s, its relevance as a viable commercial lighting source did not appear until the early 2000s with high-brightness GaN LEDs on silicon substrates. Not since Edison’s incandescent bulb have we have seen such a technological revolution and paradigm change in the lighting industry. LED lighting offers superior performance, flexibility, and energy efficiency for a wide variety of applications. Ironically, production of Edison’s original technology is now in the final stages of phase-out in the United States, and the LED is poised to be the incumbent technology going forward.

However, a funny thing happened along the way to LED lighting’s dominance – glass was left behind.

Unlike traditional incandescent and HID light sources, LED as a light source in a luminaire:

Generates its illuminance pattern combinatorially from an array of individual point sources of light (LED chips) patterned together with individual optical lenses instead of one single source (bulb) and a reflector array with a single lens
Does not generate high levels of UV and IR energy that degrade many translucent lens materials.

As a result, many lighting designers and luminaire OEMs have elected to field LED-based fixtures with only plastic lenses (acrylic, polycarbonate, etc.), with the belief that glass is no longer a necessary component of a luminaire – even for outdoor applications. The common belief is that glass no longer provided a tangible benefit in the field vs. plastics – especially in LED lighting, where UV and IR energy levels are low. Another argument is that a glass lens decreases the efficiency of a luminaire due to reflection losses.

On the contrary, history has shown glass to be the best long-term lens material choice for commercial lighting applications – especially those in outdoor or industrial environments. Glass protects the valuable components of the luminaire (light source, optics, drivers and ballast) from environmental elements – regardless whether it uses HID or LED technology. Unlike standalone plastic lenses, glass:

Does not carry a static charge which attracts dirt and debris, resulting in the depreciation of the luminaire over time
Is mechanically and chemically durable to resist degradation due to scratching and salt water exposure along coastal areas, and yellowing due to environmental UV exposure
Can be thermally or chemically strengthened for safety in case of breakage
Is a low-cost and readily available material option
Can be modified through glass chemistries (low iron), applied coatings (anti-reflective, conductive, etc.) and surface treatments (acid-etching, patterning, etc.) to optimize optical performance.

History has taught us that no material is perfect. However, throughout the history of lighting, glass has repeatedly proven to be a worthy, valuable and reliable product for a variety of light sources. When paired with LED lighting and plastic-based primary optic lenses, glass can indeed provide even more differentiated value into the same commercial lighting applications it has for more than 100 years. In the blogs ahead, I will discuss in more detail the innovative ways the industry can use glass as a lens material in this new and exciting world of LED-based lighting.

Energy

New 2016 Energy Code Impact on Commercial LED Retrofits

Fardin Posted on March 9, 2019

Before changing any of their lights to energy saving LED technology, commercial building owners and tenants need to fully understand the new 2016 regulatory impact of mandatory lighting efficiency upgrades in 41 states and Washington, D.C.

The regulations were set in motion back in March of 2015, but the cost burdens will start to sting in 2016. The new commercial building energy codes are equal to or better than ASHRAE 90.1 2004 (BCAP 2015a) – American Society of Heating, Refrigerating, and Air-Conditioning Engineers. These codes require changing lights, in part because commercial illumination is over 20 percent of any given building’s electricity costs and it is the “low hanging fruit” of energy reduction. Reducing waste in lighting through Light Emitting Diode (LED) technology is more economically viable than creating renewable power through Solar or Wind production.

Who Dodges the Lighting Change Bullet?
The codes impact the majority of the US. Over the past decade, only 11 states have lagged behind the rest regarding statewide energy codes. Alaska, Arizona, Colorado, Wyoming, North Dakota, South Dakota, Kansas, Missouri, Arkansas, Mississippi, and Maine were still using 2006 IECC codes when the other states adopted 2009 and 2012 standards – International Energy Conservation Code.

What do I have to do if I am a commercial tenant, or if I own a building?
If you improve a space that requires changing 10 percent or more of the light fixtures then you may need to change ALL of the fixtures within the space to meet the new standards. Most importantly, the ubiquitous 3-lamp fluorescent tube fixtures with T8 tubes are no longer acceptable. You have to use more energy efficient fixtures to meet the new watts-per-square-foot requirements. Your options include LED tubes and fixtures, T5 fluorescent and potentially T8F25 with Energy Star ballasts fixtures. Since LED tubes have increased dramatically in efficiency over the past five years and come down in cost, the change is less painful than it would have been previously. Except for spaces with only one fixture, multi-level switching and occupancy sensors are now required in all areas. You also need to have the occupancy sensors that can be set in vacancy mode. All spaces within 15 feet of windows must be equipped with daylight sensors with dimming or multi-level controls.

The $0 Cost Solution:
You don’t have to buy new lights. Many financing options are available, and some LED manufacturers and solutions providers will “lend” you the lights and structure a Lighting Service Contract. This Lighting as a Service (LaaS) kills two birds with one stone. You can meet the new code requirements and you reduce your monthly operating expenses, all without spending a dime.

Top Tip on Energy Code Impact:
Work with a commercial LED lighting solutions company that knows the new codes in your market or knows enough to ask the questions that will prevent any buyer’s remorse. This will help you avoid spending money twice or opening a can of worms that you regret.