LED Bulbs Save Substantial Energy • Hacker News Board

Re: LED Bulbs Save Substantial Energy

#21

Post by natch » Tue, Dec 01, 2009, 8:46 PM UTC

I was just at Home Depot this morning looking for LED 'bulbs' (using that term very loosely).

Admittedly Home Depot might not be the best place to look.

In any case, I was very disappointed. They are super dim compared to other choices. For $35 dollars you can get something with the physical size of a regular light bulb (which matters because I want to screw them into an existing fixture) but they only put out 200 lumens (!) as compared to 800 lumens for a 60-watt bulb or its ~15 watt compact fluorescent equivalent.

Looking at the design of the unit, on the light-emitting side there was an enormous span of wasted black plastic, with fake plastic unneeded heat-dissipation fins taking a bunch of space, and with three LEDs arranged in the center. With better design, you could probably fit 12 or so LEDs in the same amount of space, and then it would be a product worth buying.

Anyone know the story about why LEDs are not subsidized by state energy programs as CF bulbs are in California?

Re: LED Bulbs Save Substantial Energy

#22

Post by ardit33 » Tue, Dec 01, 2009, 9:29 PM UTC

mieses wrote: post #16

Incandescents approximate sunlight better than LED's and most other light sources. http://exploration.vanderbilt.edu/images/news/article_main/q... The health implications should be studied. Subjectively, incandescents are more pleasant than fluorescents and LED's. Our brains might be telling us something.

I agree. For soft lights/ambient lights used with a dimmer, there is nothing yet to substitute the old incandescent.

I did some shopping last night, and for my ambient light I decided to go with an incandescent. The extra energy cost is well worth it to me. Sorry environment.

Re: LED Bulbs Save Substantial Energy

#23

Post by HeyLaughingBoy » Tue, Dec 01, 2009, 9:44 PM UTC

bumblebird wrote: post #4

We have a kitchen which contains about 7 small spotlights. I thought I'd try out some LED replacements, which each contain like 10 small white LEDs. They were more expensive, but I thought it'd be worth a try. A bit like these http://nextday.diy.com/app/jsp/product/productPage.jsp?produ... The issue is, they look bright when you look at them, but they actually provide absolutely no actual light. Even when we had 7 of…

There was a very good article recently in either LED Journal (yes, there are publications dedicated to LEDs exclusively) or Electronic Design that discussed this. The problem is so many low quality manufacturers are churning out these cheap "incandescent replacements" that do little good that they are making consumers think that LEDs are a scam.

There are very good LED lamps out there, built with high efficiency, high brightness LEDs, but they are expensive.

It really is a pity. I've been experimenting with multiwatt LEDs for some time (individual, unpackaged units) for a little off-grid experiment I have going and they are scary bright! But at the consumer level, there is nothing available at low cost that is useful.

Re: LED Bulbs Save Substantial Energy

#24

Post by brucer » Tue, Dec 01, 2009, 10:35 PM UTC

natch wrote: post #21

I was just at Home Depot this morning looking for LED 'bulbs' (using that term very loosely). Admittedly Home Depot might not be the best place to look. In any case, I was very disappointed. They are super dim compared to other choices. For $35 dollars you can get something with the physical size of a regular light bulb (which matters because I want to screw them into an existing fixture) but they only put out 200 lu…

here's some that go up to 1500 lumens: http://www.ledliquidatorsinc.com/PAR_38_12_LED_Cree_light_bu...

one thing to note is with LED's the higher power ones are less efficient, so the 800 lumen lights on that page use 1/3 the power.

Re: LED Bulbs Save Substantial Energy

#25

Post by dfox » Tue, Dec 01, 2009, 10:52 PM UTC

pmjordan wrote: post #3

Now they just need to come down in price and get the spectrum right. While the fluorescent lights are already competitively priced, LED ones are still rather pricey, at about €15-20. The spectrum emitted by the pseudo-white LEDs is also unpleasant (primarily yellow + blue), the RGB ones need to become cheap enough. RGB lamps could also have some interesting extra features, like adjusting hue based on time of day, whi…

RGB LEDs tend to have very unnatural spectrum with three narrow spikes, while normal white leds (blue led + some phosphor) has very wide spectrum (albeit different from incadescents, but probably better than common fluorescent lights). Other problem that I see with most RGB LED designs is that different colors are emitted from different spots, which tends to give unnatural shadows.

Three years ago I built LED lamp out of some no-name high-power white LEDs (~1€/piece) and last year I got Phillips LivingColors lamp and subjectively I find the light given by bunch of no-name white LEDs more pleasant.

Re: LED Bulbs Save Substantial Energy

#26

Post by jrockway » Tue, Dec 01, 2009, 11:05 PM UTC

vinhboy wrote: post #11

tl;dr -- anyone have a link to the LED in the picture? it looks cool.

You probably would have scored higher and gotten a useful response if you had omitted the comment about your attention span.

Re: LED Bulbs Save Substantial Energy

#27

Post by tybris » Tue, Dec 01, 2009, 11:17 PM UTC

brianobush wrote: post #14

tybris wrote: post #12

I recently replaced a bunch of 50W of Halogen lamps (came with the apartment) with 1W LEDs. It's quite a bit darker, but I got used to having more directed light. My energy bill dropped by about 70% without any other changes. It's interesting how quickly lighting costs can run up.

Can I ask what your costs were? How long do you estimate it will take to recoup your capital costs?

I'm not sure, but 1W LED lights shouldn't be more than $10 (mine were $7,50 iirc). I could say it took me 1 month, but that wouldn't be entirely fair since I have significantly reduced the lighting and changed the way I use it. Something which I probably would not have been able to do by, for example, reducing the number of lamps since that creates an annoying bright/dark distribution of light)

Re: LED Bulbs Save Substantial Energy

#28

Post by dnsworks » Wed, Dec 02, 2009, 12:04 AM UTC

I'm personally hedging my bets on light bulbs until the replacement compromises go away. CFLs don't last nearly as long as Incandescents, and the light they cast is subpar. It is silly to spend hundreds of dollars to replace a tried and true, centuries old technology with vaporware because of effective guilt-based "green marketing".

Re: LED Bulbs Save Substantial Energy

#29

Post by Devilboy » Wed, Dec 02, 2009, 12:43 AM UTC

dfox wrote: post #25

pmjordan wrote: post #3

Now they just need to come down in price and get the spectrum right. While the fluorescent lights are already competitively priced, LED ones are still rather pricey, at about €15-20. The spectrum emitted by the pseudo-white LEDs is also unpleasant (primarily yellow + blue), the RGB ones need to become cheap enough. RGB lamps could also have some interesting extra features, like adjusting hue based on time of day, whi…

RGB LEDs tend to have very unnatural spectrum with three narrow spikes, while normal white leds (blue led + some phosphor) has very wide spectrum (albeit different from incadescents, but probably better than common fluorescent lights). Other problem that I see with most RGB LED designs is that different colors are emitted from different spots, which tends to give unnatural shadows. Three years ago I built LED lamp ou…

Really what you need to do is match the wavelenghts that our rods and cones in our eyes are most sensitive to. That should be the optimal solution in terms of energy usage.

Re: LED Bulbs Save Substantial Energy

#30

Post by RevRal » Wed, Dec 02, 2009, 12:48 AM UTC

bumblebird wrote: post #4

We have a kitchen which contains about 7 small spotlights. I thought I'd try out some LED replacements, which each contain like 10 small white LEDs. They were more expensive, but I thought it'd be worth a try. A bit like these http://nextday.diy.com/app/jsp/product/productPage.jsp?produ... The issue is, they look bright when you look at them, but they actually provide absolutely no actual light. Even when we had 7 of…

The only LED light sources in my house, besides the LEDs on some electronics, is this lamp: http://www.konceptech.com/Merchant2/merchant.mv?Screen=PROD&...

And a camping headlight.

I consider these two things to be of the coolest things I own. They definitely show off proper LED application.

For the camping headlight, which wasn't very cheap, I don't have to worry about disrupting the darkness too much. And the batteries will last forever.

For the lamp, same thing. It is a wonderful feeling staying up till 5 in the morning with nothing but you, the lamp, and your work. Nothing but the desk and your work is illuminated, and it is illuminated very pleasantly, which is awesome.

So, depending on the application, those negatives are strong positives. I can't imagine the LEDs being used as household lighting.