I was browing around on this cite, and it occured to me that we are only a few years away from replacing a very large percentage of our lighting with LED lighting.
The energy savings are dramatic. On that site is a bulb that screws into an AC standard lighting socket and puts out the equivalent light of a 60W bulb - while consuming 120mW. That’s almost energy free lighting, compared to the amount of power we use for incandescent or even flourescent lighting.
What total amount of our energy usage would we eliminate if we converted all our lighting to LED?
And a related question - what will almost-free lighting do to change the way we live? Will we keep our neighborhoods brighter at night? Keep our homes brighter? Will we start lighting up parks and rural roads?
You read it wrong - it consumes 120mA. The power consumption would be 120V*120mA=14.4W. Fluorescent lights can do better.
Most cites I’ve read say fluorescent lights are up to 2x more efficient than LEDs. The main advantage of LEDs over fluorescent bulbs is that it’s a very small light source, allowing use of lenses and reflectors to create a narrow beam. You can’t do that with a large light sources such as fluorescent lights, so you never see fluorescent car headlights or flashlights.
Than current production white LEDs, yes. Monochrome LEDs are still more efficient in terms of lumens of output per watt consumed. Of course, they suck for most lighting purposes.
I did not know that. I thought LED lighting was the most efficient lighting. Or is it just that it’s more efficient than incandescent, yet can be used in applications where flourescent is impractical?
If so, then I suppose the impact won’t be all that large.
As QED said, color LED is one of the most efficient methods of creating colored light. Fluorescents and incandescents require filters to create colored light, but LEDs create monochromatic light directly. Hence the widespread use of LEDs in traffic lights and automobile brake lamps.
White LEDs are most efficient when you need a small low-power light source. It’s an energy-efficient replacement for incandescent bulbs up to 30W or so. Beyond that, I believe HID (high intensity discharge) lamps are more efficient than LEDs. If you look at available bicycle headlights (a very demanding application, because bike riders are willing to pay hundreds of dollars for the most lightweight and efficient lighting systems), halogen lights still dominate the 6-18W range. 10-12W HID lamps are also available, and these are comparable to 20W halogens. 0.6~3W LED headlights are also widely available, and 3W LEDs are comparable to 6W halogens.
I dunno about LEDs, but I started buying fluorescent bulbs for my apartment 10 years ago, when they were horribly expensive, but even then I amortized the cost in less than a year, based on the reduction in my light bills.
Fluorescent bulbs which fit in incandescent sockets are now available much more cheaply, and you can even get “three way” fluorescents (a fairly recent development). What’s more, I purchased a pack of three 100 watt equivalent fluorescent bulbs last month for $10, which is about a quarter what they cost in 1994. And these not only come in higher wattages (both actual and equivalent), but they’re also much more compact than the early ones were; they’ll fit in most any socket, even those that are in a small space.
Unless/until they can persuade me that LED lights have become even more economical, I’ll stick with the fluoros, thanks. Granted that they don’t do well on color fidelity, but …
On my budget, I gotta try to make the most economical choices I can.
A lot of traffic lights have already been converted to LEDs. There’s thought to be in excess of 3 million such lights, perhaps 50-80% or more now LEDs. The 11-17w LEDs replaced the 150 ones. Note the red and green lights are on 50% of the time, 24/7, so the total energy reduction is quite a bit.
I only because aware of the CFL issues in the last few months and have converted about half at my home. Then just last week, I discovered 60w 4-packs for under $7. They seem to be identical to a major brand - that name doesn’t appear on the bulbs or package but the name on the package(“Bright Effects”) does appear on Sylvannia’s website.
Currently, white LEDs are made by using a bright blue LED to illuminate a phosphor, which makes white light.
Traffic lights aren’t converted for their energy savings, but because LEDs don’t burn out. When you have to change light bulbs with two guys in a cherry picker truck at $150 per hour, doing that less frequently amounts to big savings. Then there’s the safety issue of burned-out incandescents.
I’ve seen this too, and I must say, I don’t get it. I’ve seen it on brand new cars with the temporary license tag still displayed. Are automakers using the crappiest, cheapest LEDs they can get? Or is their QC just shot all to hell?
Could be poor thermal design. LEDs can be damaged by heat. And high power LEDs generate a lot of heat (a major concern when using Luxeon LEDs, but not sure about color LEDs).
Most cites I’ve read say fluorescent lights are up to 2x more efficient than LEDs. The main advantage of LEDs over fluorescent bulbs is that it’s a very small light source, /QUOTE]
and with LEDs I dont have to listen to that annoying scream put out by fluorescent lighting that drives me nuts=\
it really sucks to be able to hear that 60 cycle hum=\
<I once stopped the Navy’s audio test lab for 6 hours to find the source of the noise I wasn’t supposed to listen to=\ turns out they had not been using the tone generator as normal and were generating the tone with a different one that was damaged. I hate having extreme end hearing sometimes, but it paid the bills for a while=)>
The energy savings may be more significant that you realize. The Howstuffworks page on LED signals includes some back-of-the-envelope reckoning of electricity cost savings - they figure about $500 per year per intersection, assuming 8 lamps lit and $0.08 per kilowatt hour. Of course, larger intersections and higher-than average power costs rack up the savings even faster. A big intersection might have 20 lamps lit, and power hereabouts runs more like $0.10 to $0.12 per kilowatt hour - in that case, LED lamps could save about $1700 per year.
And I don’t mean to pooh-pooh the idea that lamp-changing costs are significant - they are. But I do expect that the majority of the payback will be electricity savings.
I’ve also seen it on very expensive new cars, less than a month old. I would feel really crappy if I had a car that cost $40,000 with burnt-out spotty lights right off the showroom floor.
That’s one type. There’s now another that uses a phosphor mixture similar to that used in standard fluorescent bulbs, which is excited by a UV LED. Then there’s a less common type that has separate red, green and blue emitters in one package, which combine to form white light.
Odds are the fluorescents you are using that work with conventional sockets are the tri-phosphor type. These are far better at color rendering than the old calcium halophosphate type and noticeably better than white LEDs. All-in-one RGB LEDs have the potential to do better yet, besides being more energy efficient.
I’m going to pick some nits here. A 12W HID is much brighter and runs longer than a 12W halogen.
My 6W-10W-15W halogen bike light has run times of:
15W 1.75 hours
10W 2.5 hours
6W 3.2 hours
This battery is 4.5Ah
The HID light on th eother hand gives the same light as a 40W halogen and has a run time of 4 hours from a 4.1Ah battery.
All of this info is from niterider
So saying that halogen dominates the 6-18 range and 10-12 HID are available is not an apples to apples comparision. There is also the cost issue.
My Digital headtrip costs about $120 currently, to upgrade to the HID storm is about $400. You get what you pay for. The extra $300 dollars tends to depress sales for all except the most hardcore.
The latest inovation from the guys at Niterider is this a combo HID and LED light. HID for trail riding and LED for when you are off your bike.