Technical Editor Margery Conner's PowerSource streams the latest developments in electronic power design and related technologies. Follow Margery on Twitter at: http://twitter.com/margeryc.
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Blog
Tuesday, October 20, 2009
So how’s that LED downlight working out for ya? Just fine, thanks.
Oct 20 2009 6:42PM | Permalink |Comments (14) |
Cree is inviting folks to submit their photos of lousy lighting. Each month Cree will give away 5 of Cree’s LED-based LR6 recessed downlights to some lucky winner. Lest you think that’s not a very big give-away, look at the lights’ current price: $98 ea.
Doug Leeper mentioned a while ago that he had bought a Cree LR6 and was pretty happy with it. The contest jogged my memory and I checked back with him to see if he still liked the light. The answer was a definite yes:
“Even my colorful marble floors looked just as colorful as they did with the incandescent. As to why it looks so bright, over the incandescent, I believe it is due to the LEDs emitting their light directly where it is to go, where as the incandescent bulb had lossy reflectors built into the bulb. Installation was a snap, all I needed was a chair to reach the ceiling and take the incandescent out, and screw in the CREE solution. I was expecting something more complicated. A year and a half later, it works wonderfully, and with the extra low power consumption, just a fraction of the incandescent, I don’t worry about turning them off all the time.”
The pricing for solid-state lights will undoubtedly drop like a stone in the years to come, but if you want your 5 LED lights now and you want them for free, get snapping/clicking.
Related entries in: Displays and indicators | LED |
Reader Comments
at 10/21/2009 3:35:25 PM, RobS said:
Carbon footprint? Wait! Is that to combat global warming? Or cooling? Didn't we already accomplish this goal by filling our households with mercury-tainted toxic CFL's???
It's all so confusing when you try to follow the greens. Hmmmmmm... ;-)
at 10/21/2009 6:12:00 PM, Polar-Ray.com said:
We have the Cree LR series on sale for $83.00 FREE SHIPPING. You can buy this product in either a warm white (LR6) or cool white (LR6-C) light. It even comes in an eyeball version if you want to direct the light.
The reason the light looks so good is because the light output is at 93 CRI. Most LED's are still down in the 80's. and common CFL's are worse. Dimming LED lights can be tricky but the Cree LR series will dim down to about 20%, provided you use the correct dimmer. This product also achieved the Energy Star rating.
Polar-Ray.com
at 10/22/2009 1:58:51 AM, Battar said:
CFL's still give more lumens per watt, more even lighting, and 20% the price.
Today, no one would ever sanction a design as inefficient as the incandescent bulb.
at 10/22/2009 11:44:40 AM, theDagda said:
RobS - CFLs have extremely small amounts of mecury; not enough to be "toxic". But of course, to people like you, FACTS have no bearing on the matter.
at 10/22/2009 1:36:51 PM, Gary said:
Go ahead. Retrofit all of your lighting with CFL's and LED's. Both are "non-linear" electrical loads that place harmonics on your electrical wiring and that of the electric utility. That causes two very negative results:
1)You must buy a wind-up clock as the harmonics will cause your plug-in alarm clock to speed up and you will get to work earlier and earlier each day.
2)The electric utility will have to replace over-rated equipment at the expense of rate payers and more consumption of natural resources to build higher capacity equipment.
at 10/22/2009 2:24:37 PM, Micro_engineer said:
Thanks "Gary", yes I will go ahead!
As a matter of fact,
1.) No need to buy a wind-up clock. I'll just get a clock with timing not based on the supply voltage.
2.) That's a bit of a stretch, don't you think. I'm willing to live with it, if it means FINALLY having lighting that doesn't make me look like a corpse in the mirror, unlike CFLs.
The (better) LEDs I've used had light that was pleasing to the eye.
at 10/22/2009 3:29:22 PM, Mark said:
Gary,
The Power factor issue you are referring to is definitely a problem with the CFL's (~45%) and the lowest of the low LED retrofit lamps. But higher output LED fixtures and LED lamps are required to have power factor correction and will all be north of 80%.
at 10/22/2009 10:30:11 PM, Dave said:
Let me know when the price per LED lamp (equivalent output to the 100W incandescent bulb) drops below $1 and I will become interested in buying some.
at 10/23/2009 5:24:39 AM, arclight said:
Hmmm...power factors in the 45% range. And those lights are more likely to be left on more often, because they "use less power". The problem is that they change the 100% power factor for lighting loads in the grid to something well less than that. That's not particularly good for the grid from an engineering standpoint.
Wonder what group of geniuses ignored this? Probably the same group that "felt good" about passing the laws mandating this nonsense without a proper engineering foundation.
It's just like the low-flow toilets...pass the law first, watch the industry and the taxpayers thrash with the results, THEN do the proper engineering to make the thing work correctly, with a several-year gap of frustration in the middle. Or the former head of the Sierra Club, who admitted some 35 years after the fact in the Washington Post that "...well, we opposed nuclear power back in 1971 because we equated it with nuclear weapons...". How's THAT for "sound engineering"???
Must we ALWAYS do our "progressive legislation" this way? Or could we for ONCE actually do REAL engineering BEFORE we pass the laws? Not a hope of doing this so long as we let our feelings dictate what we do.
Finally, this also tells me that we are not metering electrical use correctly in residential areas. Folks who seriously deflect the power factor on their service should pay dearly for the privilege; if they did, nonsense solutions like this would get stopped in their tracks until they were properly engineered. Wonder if the "smart grid" proponents are actually going to address that issue?
at 10/25/2009 9:32:18 AM, Power Factor said:
If some of you had bothered to look at the datasheet, you should have quickly realized that the power factor on the unit in this article is greater than 0.9 (or 90%)!
True, quite a few CFL lamps have a PF (power factor) in the 45% range, not too many in the 90% range.
And many LED "replacement" bulbs have power factors as bad as CFL lamps. There is already a lot of junk on the shelves. This isn't so with these lights.
Just like many other things on the market, you get what you pay for.
at 11/4/2009 8:04:41 AM, przemek klosowski said:
@dave, who said "Let me know when the price per LED lamp (equivalent output to the 100W incandescent bulb) drops below $1 and I will become interested in buying some."
You have a point that a $80 lightbulb is a novelty item, and not a good Return On Investment. However, the LED bulbs do last longer and use less energy. Considering that we pay about $1/watt/year retail energy cost, efficient bulbs do save you real money.
Of course CFLs were also supposed to last longer, and they did initially---but I think the cost-cutting on the recent product resulted in much lower reliability. I still have some CFLs that we got when they were $20-$30 in the mid-90s, but the new $1 ones tend to burn out much more quickly, with failure modes ranging from tube burns to melted components on the circuit board.
at 11/4/2009 11:57:36 PM, Ed said:
Expanding on what Przemek Klosowski said:
Looking at the overall cost (i.e. purchase price of the bulbs and cost of the electricity) the LED bulbs are much cheaper than incandescent bulbs. I also found the "soft white" bulbs made with CREE LEDs emit a white light every bit as pleasing as incandescent bulbs. I ruled out using CFL's for their harsh light characteristic in my particular application.
My calculation assumes that the LED bulbs will last as long as typically stated (i.e. usually between 40,000 and 100,000 hours).
I bought several of the higher power LED bulbs last year for about $100 each (consumes 10 watts with light output equivalent to 60 watt incandescent). I had one infant mortality after about 1 month which was replaced under warranty.
If the LED bulbs last their rated life time of 40,000 hours I will save the following for each bulb purchased:
$228 -- on reduced electricity costs
$60 -- savings not having to replace the incandescent bulb every 2000 hours at $3 each.
So, for a $100 initial investment for each bulb I will recoup $288 (228+60) over its lifetime.
If I assume that the LED bulbs are used about 12 hours daily then this will take 9 years (i.e. 80,000 hours). This amounts to a return on the investment (ROI) of 28% annually which (i.e. about 3x better than the historical return on playing the stock market of around 10% per year).
at 11/6/2009 11:49:28 AM, seacrow said:
"I don’t worry about turning them off all the time..." wonderful: some urban Greenie loves his LEDs so much he doesn't even bother turning them off. So much for power savings; sheesh.
Look instead what's been swept under the carpet. Just as new builds of Ta caps for cell phones and other lifestyle gadgets worsens the strife and war in Congo, no doubt shifting from tungsten to exotic compounds will alter global economics, politics, and investment.
So stop being stoopid about ROI from running more efficient light generators. If you want to talk real ROI, buy shares in companies actually making LEDs and shipping units with high PFs.
at 11/12/2009 7:33:01 AM, Dave said:
We had a 60W incandescent spotlight illuminating our stairs. Switch on at the top/bottom, switch off at the other end. About 10sec in total, each time the stairs used.
Replaced with 21W CFL. Takes about a minute to reach a 'safe' brightness level (dim as candles for about half a minute).
Result: It's switched on as darkness falls and stays on for hours.
Now, lets see: 60Wx6(say)x10sec/3600=1WHr/night
or, 21Wx4Hr=84WHr/night
Some saving...
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