LED lighting— yet more green BS

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I've bought 100, 100watt incandescents for $40. I reckon they will see me out and I can ignore the hype.

It should be mentioned, that the biggest stumbling block on the way of green technology proliferation is the problem with efficient-durable electric energy storage on a mass production level. Lighting devices COTS-available are, in general, relatively good.What was overlooked for decades is the importance of technological transition from electro-chemical rechargeable batteries to the capacitive power sources. Capacitors (in particular, its subset ? Ultracapacitors) have tremendous technical advantages over the batteries. To read more on this topic just refer to ?Green Electricity Initiative (GEL Initiative), which is topping Google list for many years: www.alexanderbell.us/Initiative/GEL.htm. Kind Regards, Dr. Alexander Bell Infosoft International Inc, NY

I'm in the business of LED lighting and I agree that many claims are bogus. Yet LED's are the future of lighting and they have many excellent applications. Much of the problem is that folks don't understand the product. First and foremost is beam pattern. LED's by their very nature have a very narrow beam pattern. That's why they are excellent for traffic lights but poor for a replacement of your standard 60W light bulb in your table lamp. Secondly, LED Don't like heat! People putting these into an application that doesn't allow for the dissipation of heat will find they are burning out. Thirdly, CREE LED's are not the only quality LED in the market or will they continue on top of the food-chain. I look to Nichia to be a tough competitor. Forth: Unfortunately the "Big Box" stores are the reason that many people shy away from or are disappointed by their LED purchase. Discount stores always are looking for price rather than value. As we all become informed about the proper application of LED lamps we will find them to be the light source of greatest value.

you guys all need to go to a lighting store and actually see LED''s in action. They are terrible. After months of research and an attempt to put an LED system ( to be run by solar power for my manhattan apartment) someone finally had the guts to level with me today. This guy at lighting store showed me all kinds of led lights. They are amazingly weak and could never be used for flood lights or serious reading light. But lets say you are an idiot and you are willing to pay 130 dollars for bulb you still won''t get the brightness and the light quality you need for serious functional lighting. You have to look at lumens and you need to pay particular attention to how much light reaches it target the further away you get from the bulb. The difference between LED''s and incandescent or even CFL for that matter is like the difference between whole milk and skin. I''m so tired of people touting and evangelizing technology w/o actually trying it.. or exaggerating it''s performance. Let''s get real here. Just about every LED distributor if not all say something like "a 50 watt equivalent" when the bulb''s lumens are more like equivalent to 10 or 20 watts if even that! Why is that? I am appalled by the scale of industry wide dishonesty. It''s just nuts and doesn''t make business sense.

When do we get to see Cree''s response?

Any further discussion could be reduced to the question: what kind of light source should I use for the living room? All other applications could be done with this light source to be seen at acriche.com

Whatever the technical miscues presented in the artical, Paul makes the additional mistake of equating lowest monetary cost with environmental "goodness." Simple economics might be useful if all environmental (and health, and social, etc.) costs were included in the calculations. They never are!

You hit a nerve with that C Crane VIVID-II light example. That product and its advertising is giving LEDs, which have a great future, a bad name. They claim it replaces an incandescent light bulb, but you look at the specs and it puts out something like 54 Lumens. That isn't even 10% of a 60W incandescent's output. Misinformation and making outrageous claims to peddle yesterday's technology at inflated prices is hurting the public's peception of solid state lighting in my opinion.

Paul, You would have disparaged the Wright brothers. at Kitty hawk.

When comparing benefits and disadvantages of incandescent, CFL?s and LED?s, I?m sure CFL?s would be the looser. A flood of CFL?s is available which even don?t keep their promises. But LED?s definitely surrpassed all others. Don?t try to match ?Surplus LED?s or similar? with CFL?s. There are a lot of small companies that want to take you for a ride with their ?60-LED-Lamps?. Those parts are even unable to withstand a simple EMC-Test. I don?t want to offend no one?s sensibilities but let me say: relating to efficiency and ease of use, Cree and some others are already surpassed by a foreign company which could have a bright future. This company already HAVE a 900 lm Single-Chip LED at production which consumes only 10 Watts (!) and is directly connectable to mains voltage(!). Regarding the light quality, this component is still not very convenient for lighting the living room, but for almost all other purposes, even at very low temperatures. I have installed them at the stairway with success and they are working fine despite very frequent switching.

Dude, you're not allowed to use logic or common sense when 'green' matters are concerned. It has become a religious belief to some.

Martin: How many white LED's do you install in traffic lights? Or do you prefer to read by red, green or yellow LED light? :o)

Check out the posts on the solar panel blog. www.edn.com/blog/1470000147 We see similar issues where folks are claiming ''energy'' payback on new photovoltaic cells in one to three years, but you can''t buy them at a price that makes it worthwhile. Paul is absolutely right. It ain''t green if it doesn''t make cents. Thank you for a breath of sanity in this rose colored glasses world of green.

The level of mis-information in Paul Rako's rant is astounding, especially for such a high-quality magazine as EDN. I am working on LED replacement traffic signals. Payoff in this application is 2 years, partly in energy savings and largely in maintenance savings. And, they are brighter than the lights they replace.

Your concerns are valid, although I believe your data sources are a bit dated relative to the luminous efficiency. There''s a good write up on the latest DOE testing results that highlights the fact that while there is plenty of over-statement and misrepresentation going on, there is also tremendous progress, including validated wall-plug efficiencies of 62 lumens/watt. www.solidstatelightingdesign.com/documents/view/sectornews.php?id=9748&sector=leddev#top The solid state lighting industry is making moves to get the claims under control, and there is an article 3 above that one which covers a forming industry association that plans to tackle the labeling and suitability for use marks (including vehicles to enforce those marks). As far as lifetime claims, one does have to be careful if a product isn''t sourcing LEDs from a recognized supplier. Lifetime calcs aren''t rocket-science... these are semiconductors of a general type that have been around for decades. We don''t freak out at Intel''s claimed MTBF for their latest Pentium, even when it incorporates the next steps in material and process technologies. Same here. Reputable manufs can show you lifetime versus drive current and temp curves for everything they''ve got. Best of all, and I''m admittedly biased, LED-based lighting technology continues to increase in efficiency on a steep curve. None of the existing light sources are making leaps in their efficiency. There are a few reasonably priced examples now which are cost-effective compared to CFL in 24x7 applications where quality of light makes a difference (24 hour restaurants, for instance). BTW, regular incandescents operate at about 10 lm/watt. Halogens are about 24, with CFL around 40-60. Wikipedia has a good summary of luminous efficacies www.en.wikipedia.org/wiki/Luminous_efficacy

Lots of old data and misrepresentations. But it points out a key fact in this industry, it is still a bit like the wild west out there, and there are lots of shyster vendors selling 'leds on a stick' and already issues with counterfeit components. Buy only from reputable dealers and companies like CREE, Philips, Osram/Sylvania, Lamina Lighting, and others. Delivered efficiencies of 55 lm/w (like the cree part mentioned above and include power supply) are substantially better than halogen at 15 lm/w and comparable to CFLs though not as good as T6 fluorescents at 100 lm/w. CCFLs are not a real light source except for LCD displays, and LEDs are replacing them in high end laptops (like the Apple) due to better color performance and lower battery drain. They also require a high voltage to operate. Furthermore, since an LED is a point source, its light can be easily directed and focused, while a CFL cannot (have you tried a CFL 'spot' light or even floodlight?) Additionally, the US DOE is working aggressively to provide labeling (Energy Star) and testing programs to verify performance. One final point, the accepted standard in the LED industry is 70% end of life. BTW, this is comparable to an incandescent EOL because the tungsten filament gets deposited on the inside of the bulb over time. So called 'long life' bulbs indeed have oversized filaments, the ratio of lifetime to drive current is in the 12th power so the bulbs are being underdriven and are therefore substantially less efficient. In the end, today LED lamps are technically equivalent to CFLs and substantially better suited to some applications like downlight or under cabinet light where light control is important. CFLs also have mercury which is released into the environment unless disposed of correctly. Lab demonstrations of High Brightness LED lamps in the ~100 lm/w range have already been made and chip products are on the market in the 75 lm/w. Your point about power supplies is critical, as efficiency and lifetime can be limited by these units. If we really wanted to be green, we would run our whole houses on DC current...but that's another story.

I actually bought an LED "bulb" from C Crance about 3 years ago. I can't remember the lumens or watt ratings. It was $45. It lasted 3 months. A friend tore it open to see if it was fixable (like maybe just a bad capacitor). The whole thing was toast. I'm anxious for LEDs to get to a point where they are worth it. In the meantime, my whole house is CFL. The warm up time isn't THAT annoying, and the color spectrum actually seems quite good.

Richard is absolutely correct. In fact, I switch to incandescents in several fixtures during winter months.

Some CFL''s are stated to be acceptable for use in enclosed fixtures, and many are not. I haven''t done any direct comparisons, but CFL quality, reliability, etc., seem to vary widely, even if the ratings are similar. My guess is that one only needs to look at the source of most, to figure out why. I have also found that in many instances, inexpensive (eg., about $20) 4-ft. fluorescent fixtures'' ballasts have shorter lifetimes than the bulbs that fit them! My guess is that the electronic ballasts are either easily killed by "junk" on the AC line, or are simply such poor quality that they fail sooner than a cheapo kids radio. This is not very good savings, and can''t possibly be "green". Meanwhile, there are several fluorescent fixtures in my house that must be 40 years old. They work just fine, and not one has failed in the 10 years I''ve lived there.

One thing that gets overlooked in calculating the energy savings of a non-incandescant light source is whether or not the home is in a heating mode or not. The "waste heat" from a light bulb is not actually wasted if the home is in a heating mode, since whatever BTUs added to the space by the bulb reduce the heating load on the heating appliance by an equivalent amount. If you live in a cold climate, there is no wasted heat, and thus nothing to be gained by changing from a low-cost ordinary light bulb to an expensive alternative light source.

I gave up on CFLs - the 75-W equivalents didn''t last long in my enclosed fixture, and the 200-W equivalent in my open fixture flickered, wasn''t anywhere near the spec''d lumens, and finally died after a few months. Banning incandescents would be the equivalent of RoHS - tree huggers winning out over sound science and economics.

Anyone making up a matrix of LED products finds spectrum from infrared to ultraviolet, with lasers in nearly all parts of it, and high power/high brightness in everything except the fringes. Product development is occurring at a frenetic pace, something the lighting industry in general doesn't match. This changes all the rules, and no one quite knows where that's going to go.

In my daily work (not rocket science, just automotive lighting R&D), I use 180lm tiny LEDs only requiring a 2.5W power supply. 30lm for 2W corresponds to a very old LED generation (dating back 2002/2003 maybe).

Check out Cree LED Lighting Solutions at www.creelighting.com. This is a new company that is shipping high volumes of LED downlights that change all of the rules. It provides the look and color of incandescent (no joke here) better efficiency than CFL, is dimmable, and lasts lasts 50,000 hours.

While you make a number of good points in your article, you neglect to point out that in your example using the LEDs still saves almost 2000 kWh vs. incandescent. That means reduced carbon, etc. in the environment. Your comeback might be fluorescent is more efficient and that is correct, but CFL and CCF will not focus light like LEDs. For instance try lighting art with a CFL or CCF. Also CFLs and CCF cannot fit in many of the package sizes required to retrofit existing bulb formats, such as MR16. LED is not the end all ? be all but it is well on its way and there are already applications where it is the superior solution. Also, it may be worth it for some consumers and businesses to pay a premium to be more environmentally friendly. Just because the US doesn?t have a carbon credit program like most of the rest of the world doesn?t mean we shouldn?t care about our carbon footprint.