I am a big fan of LED based lighting. I think a great benefit of these comes with low maintenance costs. With traditional bulbs and tube-lights, the entire light or the bulb has to be replaced, whereas, with LED based lighting, only the faulty LED can be replaced. I think LEDs will definitely take on the future.
I agree Werner that the thermal management is a key component of the process, and often the source of problems in the field when rigor isn't applied in development. Heat sink and TIM selection is important on the luminaire side, and with higher lumen outputs some reliable form or air movement (like Nuventix SynJet) achieves high brightness and reliability in a smaller form factor...
Himanshu the answer is yes to your question- you can definitely see inexpensive LED lamps outperform incandescents- they'll probably last longer and of course burn less energy but the tradeoffs of color temperature/quality and lifetime are variable and often not demonstrated as advertised. Since we're in the "infant" phase of the SSL maturity curve, we'll see a lot of products that turn people off in the marketplace- which is why its wise for all of us in the industry to push for quality/standards that don' t pollute the market perception as the growth inevitably happens in coming years...
Wattage may have been an acceptable way to define the amount of light being used in the traditional world. For example, as a rule of thumb incandescent and halogen technology has an efficacy of 10-15 lumens/watt and the technology isnt dramatically getting better. However, when using LEDs you have to define the amount of light you need by lumens. Every LED manufacturer and every led lighting design has different types of leds with different efficacies. You may see that some manufacturers have leds in the 50 lumens per watt range and some in the 160 lumens per watt range. If you happen to define light in wattage, then I think the manufacturer with the greater technology is at a significant disadvantage. This happens with different design scenerios as well. An LED may be 100 lumens per watt at 350mA (~1 watt) however the same led can be 80 lumens/watt at 700mA (~2.5 watts). This doesnt correlate as the same amount of light per watt. It is very important to analyse your system and figure out how much light you need on your target to assure you are using the right LED, the right quantity of leds and the proper surrounding components to design around it.
There is no doubt that one of the critical things to progress the adoption of LED lighting is education. LED system design does not need to be a bulb. The easy way to retrofit an existing fixture, that was designed with traditional technology, is by using an LED bulb. However, as the adoption progresses, you will see lighting fixtures designed specifically with LEDs permanently installed. The shape, size, styling, lifetime and efficacy of a new LED fixture will be more appealing. LEDs allow a lot more flexibility in the design of the fixture due to its small size and the heat dissipation gets conducted out the back of LED instead of radiate out the front, like traditional incandescent technology. The implementation of standards in LED lighting will also help drive adoption with quality products. The lack of education and poorly designed products in the marketplace will cause LEDs to adopt slowly in long lifetime expected applications.
There are many different softwares available on the market. One type of software, typically used by lighting designers and architects, is light rendering software. This type of software allows a user to build an environment similiar to what they would have in a real life setting. Files readily available from fixture manufacturers can be imported to render the effect the light will have on the environment. The second kind of software used is more for optical lens and reflector design. This type of software allows a user to customize an optic to shape the light exactly on their target area.
The cost difference between a poorly designed LED system and the proper design can be small to significant depending on the compromises one would make. 60 Watt equivalent LED light bulbs are just starting to hit big box stores now. Until recently, it was impossible to meet this requirement, mostly because of the amount of thermal mass needed in the design. Lifetime, efficacy, color consistency and color uniformity are key metrics to consider when designing this type of application. If all these metrics are important in ones design, then a poorly designed led system can never outperform any conventional lightbulb.
As a LED consultant these are my quick keys to analysing any LED bulb.
1. Where is it made. Chinese bulbs use old technology and often times try to replicate a product made elsewhere with an abandon for solid design. This leads to:
Faster bulb dimming: LED's don't just burn out they get dimmer and dimmer, this is most often caused by the overheating of the led and chipset. A chinese LED works much better if it is blinking or only used for short periods as it won't heat. Just recently the department of Justice in Washington bought 150 Chinese PAR-38's for a new courthouse. These bulbs melted from their alluminum housing and fell to the floor, just the led's the rest was still screwed in. We also conducted a test for a Fortune 100 company with troffers and the Chinese T8/T12 replacement lights had dimmed by 30% in 7 months while ours was still at original brightness.
2. Look at a bulbs lumens and divide this by the wattage. This will get you its efficiency and allow you to compare bulbs with different wattages.For example the MR-16 bulb I sell works at 4.5 watts and puts out 420lm. This is an efficiency of 93.333 lumens per watt, the average incandecent is 10lm/watt so a 100watt bulb has 1000 lumens. Here is a comparison I have of lumen efficiency of some LED companies http://bit.ly/dZzmJw please let me know if you find any more that I should add.
And a simple rule of thumb is if you can find a LED with a lower wattage and comparable brightness, choose that one because the light will depreciate at a slower rate due to reduced heat load.
Thanks for the information on LED lighting designs. My questions are, how do I know that a designer is not intentionally using less "wattage"? Is there any form of consumer protection mechanism to identify such bad designers other than references from people the designer has worked with in the past?
It is not true that poorly designed LED light can still out perform the CFL light. Poor design might cause many problems which will initially rresult in reduce in performance and finally may actually completely broke. I accept with the statement the solid state lighting is only as strong as a weakest component in the design. This is true because solid state lighting involves more components like PCB, LED's, driver chips and also few passive components. But a CFL are manufactured with stable manufacturing process which is in existence for quite a long years already.
EBN Dialogue enables and encourages you to participate in live chats with notable leaders and luminaries. Not only editors and journalists, but the entire EBN community is able to comment and ask questions. Listed below are upcoming and archived chats.
Thailand Stages a Comeback Join EBN contributor Jennifer Baljko on Thursday August 23, 2012, at 11:00 a.m. EST for a live chat on how electronic manufacturers in Thailand have shored up their supply chain to reduce the impact of future natural disasters.
Microsoft Surface: Potential Winners & Losers What are the implications for the electronics industry supply chain of Microsoft Corp.'s decision to launch its own tablet PC? Join industry veteran and EE Times' systems and OEM expert Rick Merritt on Tuesday, July 3, at 12:00 pm EDT for a Live Chat on this subject.
Join EBN contributor Jennifer Baljko on Thursday August 23, 2012, at 11:00 a.m. EST for a live chat on how electronic manufacturers in Thailand have shored up their supply chain to reduce the impact of future natural disasters.
Peter Drucker famously said "Trying to predict the future is like trying to drive down a country road at night with no lights while looking out the back window." Yet in the razor's-edge world of electronics—with a lean supply chain and just-in-time demands—the need to know the future is vital.
While no one really can accurately predict the future, we can take guidance from another Drucker saying which is the best way to predict the future is to create it.
You've heard the saying "the No. 1 supply chain risk is your people." That hasn't always been the case. But today's complex global supply chain requires a new type of multitalented employee. It's one who understands, finance, marketing, economics, is savvy with technology, graceful with relationships and can think analytically.
Where are these people? Are universities properly preparing the next generation supply chain professionals? How do train your existing workforce for these new, demanding positions?
Brian Fuller, editor-in-chief of EBN, will lead a 60-minute Avnet Velocity panel discussion that will ask and answer these and other questions swirling around today's supply-chain talent challenges.