Someone asked me how long LED last. I read in a LinkedIn group discussion ("Hot Buttons In Lighting") that EPA is considering lowering the ENERGY STAR requirement for LED from 15,000–20,000 to 10,000 hours to lower cost, make LED and CFL equivalent, and make LED more affordable.
There are good reasons to lower the lifetime or raise it. But what do we tell people who ask? And what do you think EPA should do?
LED lights are still very young, so I don't believe the longevity of the LED's themselves plays much of a roll in the price. Silicon devices simply last a long time. I would want to see how much of a savings they are talking about. Longevity is generally a mark of quality.
The other aspect is the warrantied life and the expected life. The last ones I just bought had a 50,000 hour expected life with a 5 year warranty for $10. And, you can expect prices to be coming down.
Advice for my customers is to watch for sales to replace the high usage and hard to reach lamps with LEDs. CFL's are still very cost effective if they don't mind the drawbacks.
The EPA doesn't set the "longetivity standards" or control costs
One reason why the longetivity has been dropping is due to the newer testing requirments brought on by the industry pushing back at inferior bulbs coming to market which unfortunatly raises the cose & for most companies it is easier to derate their bulbs.
The biggest factor that impacts longetivity is - for every degree that the driver is above its design temperature, the life of the bulb is shortened by 10%
For more on this - http://blog.sls-construction.com/2012/alabama-code-and-misc-updates
LED's last for YEARS, how long has that clock radio by your bed been displaying digits? It's the drive circuits that fail, I've not found bad LED's that haven't been overdriven/overheated...
You hit the nail on the head when you state it's
about TJ temperatures- and drive current !
It's an accurate assessment !
As I am a LED lighting expert I guess I should respond factually a LED the diode itself
will last many 10's of thousands of hours- what I beleive your refering to is LED luminiare
lifetimes.The numbers vary from wildly 2000 hrs to 70,000 hrs +. Effective
engineering, design & the use of quality components are critical .
As for equivilancy in LEDs vs CFL, CFL's are technically inferior- their market share peaked
2 years ago at 19% of the lamps sold & that share is declining (due to LEDs).
As for the EPA's role - the SSL advancements are one thing - EPA issues are a diiferent
thing altogether-many in the biz wish the EPA would get out of the way. I could say
about 14 milllion additional words on the topic of Solid State lighting & the subset of
standard form factor LED luminiares but I've been working on being succinct.
The issues with LED's vs CFL's is there isn't hardly any energy savings between the 2. Lumen per watt they are very close, yet LED's cost 5X the price of CFL. LED manufacturers need to push things like color quality, and focus on specialty devices such as recessed can retrofit kits. I do think CFL's are a transitional technology until LED prices drop some more. As LEDs become more commonplace the "cool factor" will wear off and prices will need to drop.
Currently the best way to get high lumen per watt while keeping CRI above 80 is the traditional 4' T8 or T5 lamp. We're talking about 85 lumen per watt, 2,750 total lumen for the grand cost of $4 with a 20,000hr rated life. It's rare to see LED lamps with lumen ratings over 1000, I've not seen one less than $40. I've also never seen CRI listed on CFL or LED lighting...
A quick rebuttal LED often exceed CFL efficiencies now - and from a commercial stand point
the maintence on SSL performing well in to 12 -18 years is a better product based on operational costs
I have 2006 year model stuff ( which is real rudimentry compared to my modern era stuff) AND
these oldies but goodies will go 4- 5 more years-
They work fine - CFLs are not as good when evaluated where maintenance costs are factored in.
Also in time they just won't make 'em anymore - the're a product that's going to "die off" maybe 5 years to 10 yrs but somewhere soon They simply won't be manufactured any where ! Even China.
And Lighting trends today see lighting controls being used with lighting easy for SSL a bad
fit for performance when coupled with flourescent -it's an outdated approach in 2012
As for cool factor I won't dispute that SSL has "cool factor " between COOL LED STUFF +
Cooler OLED Stuff I would think it will be a decade before the novelty / coolness is moot or wares off
On the last part I would say if you were to walk thru the LED shows displays or attend Lightfair
you would see things that would dazzle you- both with their performance numbers but by their
being interoperable computer type things laden with features --that just happen light a room
- And are the size of a push pin !
Agreed, CFL is a transitional technology, LED will eventually replace in low to medium lumen applications. What are your thoughts about when LED will finally dethrone the traditional 4' T8/T5 lamps? At $4 for 2,750 lumen, LEDs have a LONG way to go before they can catch up. T8 is the most popular lighting in commercial applications...
LED offerings to replace outdated flourescent tubes include :
Tube LED products - this won't be the platform, trying to squeeze light out of poorly
engineered items that happen to share the physical dimensions of incumbant tubes.
It's a choice but not highly regarded in the industry- these are the place holder products
There are strip configurations that come together as modules, kinda like flat rectangular
legos that snap together, the Philips Fortisimo stuff is interesting, its early to
judge the approach - but Philips has put alot of money in to it - we'll see .
Cree- Beta LED provide a troffer replacement with a strip of well engineered CREE
chips in a pretty good physical formats with bi level settings, (an industry leader)
There are about 40 different planar configured light panels - many are thin, effective
& have good photometric and decent radiometric performance numbers.
But what I think will eventually supplant them all are OLED panels - I am an ardent
proponent of OLEDs - they can be as thin as 2 mil - when made in a rol to roll process
they can be mfg like rolls of vinyl flooring -regionally made near where they would be used
instead of a "parts from & fabricated in China " with OLEDs right now the best performance is
getting 124 L/pw with a 20,000 lifespan - within seasons it should be around 170 L/pw.
when architechs and lighting designers can have something akin to lumenescent wall-
paper which runs off a small battery ( w/an ultra capacitor) is interoperable and tuneable
thats what folks will use - standard troffer configuration fixtures are dinosaurs.
The economics of using old tech lighting can't compete ( going forward -circa next year)
withwell designed 21st century products.
Thanks for your comments. I did find some LED recessed can retrofit kits and installed a few of them in my home. Got them at Home Depot and I think I paid $30 each. After the first one they were very easy to install. So far we are very happy with them.
Wow, glad I got the ball rolling on this discussion. Thanks all for your valuable comments. Home Energy Pros rocks!
For what it's worth, in parts of the country where cooling costs are a substantial chunk of change, LED lighting is a godsend, especially when replacing incandescents, but also to some extent in upgrading from CFLs. Think temperature of bulbs at 70, 141 and 315. Cree has a sales presentation online that calculates and compares costs and savings, and this 'Eliminated Cooling' amount is of course a huge item.
When you consider that LEDs offer a chance to seal and insulate over a ceiling 100% and eliminate ALL penetrations while still enjoying recessed lighting's snazzy splay of lights, what we have here is the most crucial surface in a home - the ceiling - regaining its critical seal and saying goodbye to bypasses and little launch pads for household air to depart and outside air to infiltrate. LEDs' primary benefit is not just cool and dimmable, non-mercuric beautiful light, but rather the facts that it makes it without the attendant heat that at one time in history required venting household air in order to keep from burning the place down.