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irrig8r
04-18-2012, 10:11 PM
http://www.homedepot.com/Lighting-Fans-Light-Bulbs-LED/h_d1/N-5yc1vZ1xh4Zbmg0/R-202188260/h_d2/ProductDisplay?catalogId=10053&langId=-1&storeId=10051

I was in my local HD and saw this display today.
$9.97 each for 8.6 W A19 LEDs, supposedly equivalent to 40 W.
Label says they're dimmable.

Life: 46 years (Based on 3 hrs/day)
Light Appearance: 3000K Bright White (WW)
Energy Used: 8 Watts (equivalent to a 40 watt standard incandescent lght bulb)
Lumens per Watt: 54

Looks like Eco Smart is an HD brand.


Handwritten cardboard sign said these bulbs would last 40 years....

Consumers Reports member reviewers like them:

http://www.consumerreports.org/cro/home-garden/home-improvement/lightbulbs/lightbulb-ratings/models/user-reviews/ecosmart-a-19-led-bright-white-40w-ecs-19ww-120-864680-home-depot-99040577.htm#readReview

Does this mean LEDs are coming down in price or are they flooding the market with a loss leader?

David Gretzmier
04-18-2012, 11:34 PM
This kind of turned into a soapbox thing for me-

I think that is a cheap price, but a couple of thoughts- at 430 lumens, in a frosted or lampshade fixture, I think you are going to need several of them in a fixture to be able to see or read by.

I have a short lamp 1600 lumen 23 watt flourescent twist beside my bed in a shaded lamp, and it is barely enough to read by.

I think it would be perfect for the light you use as a night light that is on all night long or even 24/7.

I think 54 lumens per watt is about what I am seeing from most LED bulbs out there.

I guess my beef is why do t5 and t8 flourescent 4 foot tubes get 90-105 lumens per watt or more, are rated at 24-36000 hours, and come in 3000k, and cost 1-6 bucks per bulb. I have about a hundred t8's in my shop that are rated at 25000 hours, 28 watts, 5000 kelvin, and they each put out 2900 lumens. I bought them in 3 packs of 40 bulbs, and paid 1.19 per bulb.

I do get that LED's are instant on and no warm up, and they tyically are rated to 50,000 hours at 80% lumen maint. also very little mercury.

metal halides and high pressure sodium bulbs also can get around 100 lumens per watt, but at a much uglier color temperature.

I am fairly certain that most of the LED light bulbs out on the market today are using the older LED chips and are only producing 50-60 lumens per watt.
The newest warm white 3000k cree xml LED's are readily available and are rated at 110 lumens per watt. the higher color temperatures xml's do far better, at around 160 lumens per watt at around 5000k. They also hold up to 100 lumens per watt even when driven up to 1000 lumens or 10 watts. you can find these in flashlights all day long.

I am hoping that in the next few years these chips will make their way to consumer bulbs and start exceeding the energy efficiency of existing technology.

I'd also like to see a 100 watt equivalent in an LED that looks like a regular a19 shape. they have some LED bulbs in spotlight form in the par 30's and 40's, about up to 1300 lumens for around 40 bucks. but the brightest LED traditional bulb shape I have seen is around 800 lumens or a 60 watt equiv. 2 of those are about what you need in a hall fixture or table lamp. a single 100 watter equiv. is needed as those bulbs are disappearing this year.