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Is the Future Bright for the California Quality Lamp?

The California Energy Commission (CEC) in conjunction with the California Public Utilities Commission (CPUC) drafted and adopted a document for a new California Quality Lamp, which is currently voluntary. However, beginning in 2014, only LED replacement lamps that meet this new specification will be eligible for rebates in the state. The rationale and drive behind the new specification is to promote quality of light over cheaper, poorer LED replacement lamps that may negatively impact consumer adoption of high efficiency LED light sources.

Development of the new spec was fueled by the historic low adoption rate of poor quality CFL bulbs, which began flooding the market in the 90s when China ramped up mass production of the helical CFL design. Utilities, wanting to reduce energy consumption due to rising oil costs and global warming, encouraged residential consumers to swap out incandescent lamps for CFLs through rebates and buy-downs. Unfortunately, the ultimate market penetration of the CFL was extremely low (roughly 11 percent nationally and 20 percent in California) due to the performance and perceived value of the CFL. Noticeable flaws in CFLs were poor quality of light, the inability to dim, the short life, the flicker, the buzz, the shape, the slow start up in cold weather and the mercury content. This overall lack in comparable product performance drove the consumer back to incandescent bulbs as the primary choice on the basis of both price and quality.

In a nutshell, the perfect storm of events occurred in the US lighting industry demonstrating the importance of all Four P’s of the ‘marketing mix’ – product, price, promotion and place. The results have created a long lasting negative view of CFLs despite significant product improvements in almost all attributes.

The introduction of the California Quality Lamp is positioned by the CEC and CPUC to be the game changer in product performance for energy efficient replacement lamps. Key lessons were learned from the failed CFL marketing approach and, as a result, the voluntary CEC spec focuses primarily on LED light quality, dimmability and longevity while adopting Energy Star performance criteria in other areas such as efficacy. The CEC allows only omnidirectional, floodlamps and spotlights to be qualified as California Quality (refer to summary table of select criteria below).

Product performance is but one of the Four P’s of the traditional marketing mix and understandably, the CEC cannot alone significantly impact the other three factors of price, promotion or the place of sale/method of distribution. So how will the California Quality Lamp succeed and what is the broader plan?

The white paper, “Relighting American Homes with LEDs”, and the DOE study on ‘Lessons Learned’ as cited in Appendix D of the Voluntary California Quality LED Lamp Specification, certainly seem to point toward a more consumer-oriented niche marketing program, collectively known as the Four C’s.

  • Understand and focus on what the Consumer needs rather than the product alone
  • Shift from price to Cost of ownership, i.e. long term value
  • Replace promotion with Communication which includes emphasis on education, environmental impact, advertising and incorporate use of social networks
  • The place and method of distribution should offer Convenience utilizing channels such as the internet and other trends in purchasing

You have the hindsight and the foresight to make the light right! Good luck California, and as always, you lead the way.

Summary of Select Residential California Quality Lamp requirements vs. Energy Star Requirements

Performance Criteria California Quality Lamp Energy Star Lamps
Lamp base and Lamp Shape Limited to Omnidirectional, spotlight and newly defined flood lamps Open to more bases, shapes and decorative lamps
Efficacy Not required Between 40 – 50 lumens/Watt depending on lamp type
Light Output at Elevated Temps Not Required 90% or greater output at elevated temperature
Correlated Color Temp – CCT Only 2700K and 3000K 2700K, 3000K, 3500K, 4000/4100K and 5000K
Color Rendering Index – CRI CRI ≥90 and R9=.50 CRI≥80 and R9=0
Dimming, noise, flicker 100% – 10%, free of noise and flicker No established criteria
Lumen Maintenance Not Required Shall maintain ≥80% of output at 40% of rated life
Rated Life Same as Energy Star Not less than 25,000 hours for residential lamps
Power Factor Pf ≥.9 Pf ≥.7
Electrical Safety Not Required Must Comply with UL1993 and UL8750
Warranty Minimum 5 year Warranty Provide a Warranty period (not specified) and contact information for manufacturer
Categories Lamp

What Goes into the Design of LED Retrofit Lamps?

In a LED retrofit lamp, it is the light engine comprised of LEDs (discrete or chip on board) that emits the light that you see. The LEDs in the lamp operate at a temperature much higher than ambient, resulting in lower lumens, and this thermal efficiency factor lowers the lamp efficacy (lumens per Watt or LPW) below that of the intrinsic LEDs. Depending on the application, some LED lamps also have a form of secondary optics to shape the pattern of the light. Not all the light emitted by the LEDs makes its way out of the lamp. There is a light extraction efficiency associated with the whole optical system and this also lowers the efficacy of the lamp below that of the intrinsic LEDs. Finally, there is a driver efficiency factor (not all of the input power to the lamp ends up being delivered to the LEDs) which again reduces the lamp efficacy. It is the product of these three individual efficiencies which gives the overall factor to help the designer determine the final lamp efficacy.

Lamp designers from reputable manufacturers focus on lamp performance while accounting for each of the efficiencies mentioned above and also keeping in mind the need for the product to be affordable. Fly-by-night vendors often do not understand or care about these efficiencies.

In general, higher thermal efficiency is associated with a lower LED solder point temperature. This is possible with good thermal management by a suitable combination of proper materials for the heat sink, adequate surface area, proper choice of interface materials and good contact protocols. High optical efficiency, especially for omni-directional lamps, may need suitable lens design and proper choice of optical materials.

Driver electronics is complicated. A high efficiency driver allows one to reduce the total input power to the lamp for a given lumen output from a specified light engine. This is because in a high efficiency driver fewer watts are lost in the driver circuitry with a larger fraction of the input power being delivered to the LEDs. Power dissipation in the driver results in heat so a higher efficiency driver helps lower the temperature of the driver components allowing the use of lower cost capacitors and inductors for example.

Various design attributes influence the driver efficiency. One of them is whether the driver is isolated or non-isolated. While the latter tends to have lower losses and higher efficiency, one has to be careful to ensure that electrical safety requirements are met to avoid any shock etc. Unlike fly-by-night vendors, reputable manufacturers of LED lamps pay proper attention to this. A non-isolated driver design generally calls for fewer components, allowing a smaller driver footprint, and so is preferred for smaller form factor lamps.

Dimming performance is directly related to the driver design. Dimming drivers, for example, incorporate a bleeder circuit with resistive and capacitive components that provides the latching and holding current and prevents the TRIAC from misfiring. Bleeders can be passive or active. An active bleeder, where the resistor is only on when needed, may be the preferred route when high driver efficiency is needed. This may happen when one has to design a higher wattage LEDr lamp while keeping the cost of the heat sink under control. In this case, driver component temperatures are very critical. A passive bleeder may suffice for low wattage LEDr lamps where the driver efficiency may not be that critical. Even the type of fuse that is used for the driver can influence the dimming performance and also affect the driver efficiency.

In summary, several complex technical variables influence the optical, thermal and driver efficiencies in a LED lamp. Reputable manufacturers differ from the crowd of lesser vendors in that the former pay attention to all of these efficiencies when they design lamps for the customer while keeping cost in mind.

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Improvements in LED Lamps

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.

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ENERGY STAR Lamp Standard Update

At the end of August, the EPA released the final version of the ENERGY STAR Lamps v1.0 Specification. This for the first time harmonizes the requirements for energy efficient compact fluorescent (CFL) and LED Lamps into one overarching set of requirements.While the ENERGY STAR lamp standards are voluntary, many retailers view compliance as a mark of excellence and the purchasing arms of US Federal agencies are required to purchase products that meet the standards.


Moreover, this is usually the benchmark that utilities use for eligibility to rebate programs so it is a force on the market for energy efficient lighting. For the LED lighting community, this new standard will supersede the existing Integral LED Lamps v1.4 specification when the new v1.0 standard goes into effect September 30, 2014. In my May article, I described in detail some of the key differences between the old v1.4 standard and at the time draft specification as it applied to LED lamps. To manufacturers, a more relevant milestone will be May 30, 2014 as this is when the lamp certifications bodies must stop certifying new products to the existing v1.4 specification. The table below summarizes the some key parameters between the old and new standard.


Standardization is a time consuming process and there is always vigorous interchange between the interested constituencies such as manufacturers, utilities, energy conservation groups, government agencies and retailers to come up with an acceptable balance. This standard was no different, especially since there were quite a few differences between how the CFL and LED lamps programs had approached technical requirements, in fact the first public discussions on this standard started in March 2011. On the LED front, some may be disappointed with the results in areas such as energy conservation, since the lumen efficacy bar at the lower wattage levels have only raised by ~ 10 percent and in fact for omni-directional lamps in the 10 to 15 W range, no improvement in efficacy is required over the old standard. This is an acknowledgement that initial purchase price is a bigger barrier to LED adoption than total energy consumption over lifetime. In other areas, clear progress has been made.

Dimmablity is not a requirement for LED bulbs but for the first time, there is now a minimal set of performance requirements for bulbs labeled as dimmable. In this case, a bulb must be dimmable to at least 20 percent lumen output and be tested with at least five dimmers from two manufacturers and be tested with 1 and 4 lamps in the circuit. While this is a far cry from the typical behavior of incandescent and halogen, it is a first step. Also in the dimming area, the standard does provide an alternate performance criteria based on the released at the end of April 2013, National Electrical Manufacturers Association (NEMA) SSL7A dimmer/lamp interface standard. A good tutorial on SSL7A can be found here. While less visible than ENERGY STAR in the market, the SSL7A standard should have significant long term implications as it defines a common interface definition between new dimmers and lamps that come on the market. So as NEMA SSL7A compliant lamps and dimmers enter the market, lighting architects, installers, and consumers will be able to have better confidence of purchasing dimmable lamps that meet some set of minimal criteria. None of these standards ensure incandescent equivalent dimming behavior so performance testing at the consumer/specifier level to separate the good from the best-of-breed products is still required and bulbs from different vendors installed on the same circuit can respond differently as they are dimmed but at least the industry is moving in the right direction. One requirement that was removed from the final v1.0 specification was a maximum limit for the flicker index of dimmable bulbs. Instead for manufacturers, the only requirement in this area at this time is to report the flicker index as part of the qualification reporting. This could be viewed as a first step to gathering flicker index performance on a large set of bulbs so that in the future it might be possible to establish objective thresholds on this parameter which is still being studied.

In the next 12 months, manufacturers will have their hands full preparing for the effective date of this new bulb standard. Fortunately in many areas, the changes are not a dramatic shift but more of a minor course correction. Going forward though future versions of this standard will no doubt be expanded to improve dimming criteria as well as incorporate new products such as Smart Wireless controlled bulbs as well as Zhaga compliant Light Engines that are coming on the market and are expected to reach broader adoption.